最新文献报导
2008 年第 3 期（总第 20 期）
3
2008
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《最新文献报导》2008 年第 3 期
目 次
光电跟踪 .................................................................................................................................... 1
光纤激光陀螺 ............................................................................................................................ 3
飞秒激光脉冲 ............................................................................................................................ 4
成像光谱 .................................................................................................................................... 7
太阳能电池 .............................................................................................................................. 11
Femtosecond and Attosecond Pulse ......................................................................................... 13
High-Power Laser and Solid-State Laser ................................................................................. 21
Laser Application ..................................................................................................................... 25
Nonlinear Optics ...................................................................................................................... 28
Space Optical System ............................................................................................................... 31
Imaging Spectrometry .............................................................................................................. 37
Tracking of The Moving Target ............................................................................................... 44
Ultraviolet Imaging \Detection................................................................................................. 49
Optical tweezers/ Photochromic............................................................................................... 56
Fiber Amplifier ......................................................................................................................... 60
Optic Communication .............................................................................................................. 62
Large Aperture Mirror .............................................................................................................. 64
XIOPM latest Documents Report
光电跟踪
1]某经纬仪垂直轴系刚度分析
类成华;王守印;李延伟;, 计算机仿真, 2008,(04), 313-316
光电经纬仪垂直轴系由于负荷重、转动惯量大,其刚度将直接影响经纬仪的跟踪性能,所以其方位谐振频率
显得更为重要,针对这种情况,在与传统的仿真分析软件 MSC.patran 进行对比的情况下,采用了三维建模软件
UGNX4.0 自身集成的建模仿真一体化功能对经纬仪垂直轴系进行了模态分析,得到了垂直轴系前三阶固有频率
及振型,仿真结果满足实际工作需要,并且找到了刚度薄弱环节,能够指导以后的优化设计工作。并通过实验实测
方位转动谐振频率,与仿真分析结果进行比对,验证了仿真分析方法的可行性。
[2]外场多光轴瞄准偏差测试的基准光轴建立方法
高明;侯宏录;, 光子学报, 2008,(05), 1029-1033
提出一种针对外场真实环境下可见光、激光和红外多光轴瞄准系统瞄准偏差测试的基准光轴建立方法.采用
精密大地测距、测角技术获得观测仪器站址坐标、基准光轴方向和靶标中心位置,通过对标定靶标上的中心点作
测距和测角观测,并对基准光轴方向大气折射和地球曲率引入的误差进行改正,获得基准光轴、激光和红外系统
在靶标上的精确位置.理论分析和实际测试结果表明,该方法具有理论严密、测量准确度高、工程上易于实现的
优点,在 2km 范围内基准光轴误差小于 4.5″,完全满足多光谱多光轴动态瞄准偏差测试中基准光轴准确度的要求.
[3]二维指向镜的成像特性分析
李淑英;周世椿;, 光电工程, 2008,(05), 17-22
目标搜索和跟踪一体化的光电探测系统常采用二维指向镜与面阵凝视成像探测相结合的技术方案。本文在
光学矢量反射理论的基础上,对二维指向镜的成像特性进行了分析,给出了扫描轨迹的计算,指向镜摆动角度与视
线角之间的关系。当指向镜绕两轴转动时,物体反射像也随着指向镜的转动产生像旋,扫描轨迹呈非线性变化。
文中讨论了多元探测器像旋角的计算和对跟踪系统的影响,为软件校正像旋和二维控制实现精确跟踪提供理论参
考价值。
[4]基于环形光电探测器的多目标探测与跟踪研究
宋勇;郝群;李翔;王永松;, 光电工程, 2008,(05), 6-11
提出并研究了基于环形光电探测器的多目标探测与跟踪技术。首先提出了一种基于 6 片线阵 CCD 的环形
探测器设计。该探测器中的每一线阵 CCD 光学系统的光轴均通过探测器中心点,且任意两光轴之间的夹角为
60°,形成具有 360°视场的环形探测结构;提出了基于目标信号脉宽判据、基于目标信号水平尺度比率的复合判
据,研究了适用于环形探测器的多目标快速识别与跟踪算法;建立了硬件实验系统,并进行了功能验证实验,实验结
果表明:所提出的环形光电探测器及算法设计可实现多个运动目标的探测与跟踪,在目标机器视觉、虚拟现实等
领域具有潜在的应用前景。
[5]新型动态多光学目标模拟装置研究
马军;何煦;韩冰;, 应用光学, 2008,(03), 374-379
介绍了多光学系统观测平台的检测方法现状,列举了现有检测用光电靶标的局限性。叙述了动态光学靶标的
功能原理,提出一种新的检测设备,即双光源动态光电目标模拟装置的设计方案。并对其进行了理论分析和可行
性论证。着重对坐标变换过程进行了演算,证明基准转换的正确性。结合理论基础和现有的工程设计经验,论述
了该新型双光源动态光电目标模拟装置的工程化设计方案。最后对该设计方案的最终精度进行了分析,验证了该
设计方案可以满足多光学系统观测平台的综合检测和标定需求。
[6]自适应模糊 PID 控制器在跟踪器瞄准线稳定系统中的应用
姬伟;李奇;, 控制理论与应用, 2008,(02), 278-282
针对陀螺惯性平台上的跟踪器瞄准线稳定系统中非线性不确定因素对稳定精度的影响,设计了一种自适应模
糊 PID 复合控制策略.提出了改进的自适应调整因子和学习算法进行控制参数和规则的在线修正;采用 PID 控制
克服模糊控制固有的精度盲区.实验结果表明该方法在一定测量噪声和速度敏感范围内,能有效地隔离载体扰动,
保证跟踪器对目标的准确瞄准,具有动态响应快、稳定精度高、自适应抗干扰鲁棒性强等特点.
[7]嵌入式光电综合控制系统研究
何艳丽;谭立新;, 中州大学学报, 2008,(01), 119-121
简要介绍了嵌入式光电综合控制系统的系统组成、硬件结构、软件设计等内容,分析了其设计特点,给出了
实现方法。
[8]舰载光电跟踪的船摇扰动复合补偿控制
王辉华;刘文化;张世英;张文博;, 海军工程大学学报, 2008,(02), 81-84
最新文献报导
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XIOPM latest Documents Report
针对船摇扰动引起的机械谐振和视轴不稳定的问题,舰载条件下通过安装多个陀螺来实现船摇扰动的复合补
偿,在原有等效闭环系统中串入高通滤波器,消除谐振环节带来的影响。从仿真结果看,复合补偿控制具有良好船
摇隔离效果,有利于高精度跟踪系统的实现。
[9]基于 89C2051 和 MAX187 的变焦镜头控制器的设计
杜继伟;王庆智;邓志辉;, 航空兵器, 2008,(02), 52-55
可变焦一体化 CCD 摄像机是光电跟踪仪的关键部件之一,担负着图像采集的任务。本文介绍了可变焦一体
化 CCD 摄像机中的一种基于 89C2051 单片机和 MAX187 A/D 转换器的变焦镜头控制器进行变焦和聚焦控制,以
及焦距反馈的原理及实现方法。
[10]低空猎手 波兰“劳拉”近程防空系统
707;, 现代兵器, 2008,(05), 14-18
07 年岁末,某公开杂志的一张中国新型双 35 毫米自行高炮的照片在网络上掀起了一场自行高炮热。对于其
渊源网友们提出了很多种猜测,在众多猜测中,外型与中国新双 35 自行高炮最为神似的波兰"劳拉"自行高炮成为
网友们议论的热点。更有些人一度认为"劳拉"是世界上最先进的自行高炮,并进一步认为中国新型双 35 毫米自
行高炮拥有与"劳拉"一样优秀的性能。那么,"劳拉"究竟是一套怎样的系统呢?
[11]基于 CNN 的海空目标检测
刘天华;杨绍清;刘松涛;, 现代电子技术, 2008,(09), 51-53+56
针对海空目标运动速度快,机动频繁,要对其既准又快的识别和跟踪,算法和硬件都要求很高的特点,提出了一
种新的基于元胞神经网络(CNN)海空目标检测方法。通过大量的仿真实验证明,CNN 与传统的方法如各种梯度
算子、形态学、小波等相比,其处理结果更加完整细腻,细节更加突出,有利于提取目标的细微特征,特别是对于以
云层、海浪为背景的海空光电目标,能更好地进行目标检测。该方法收敛时间快,适合高速并行信号处理,能满足
实时处理的要求,因此在军事上具有较大的应用潜力。
[12]机载红外搜索与跟踪系统的现状与发展
李富栋;, 激光与红外, 2008,(05), 409-412
介绍了机载红外搜索与跟踪系统的发展历程以及装备的研制、改进情况,指出了在现代战争中发展红外与搜
索系统的优势和重要性,重点探讨了几种红外与搜索系统的性能及其特点,最后论述了机载红外搜索与跟踪系统
的现状与发展。
[13]某型激光导引头光电系统建模与测试方法研究
刘敏;, 光学技术, 2008,(02), 189-193
建立了激光导引头跟踪回路的数学模型,根据实际情况设计了仿真系统环境,提出了一个易于实现的可靠的
激光导引头静态测试和动态测试的仿真系统方案以及在全弹道仿真条件下验证导引头数学模型准确度的仿真方
案。目前该系统已经成功应用于某型激光制导武器的半实物仿真。
[14]基于改进概率数据关联滤波的红外小运动目标跟踪
李正周;金钢;董能力;, 电子与信息学报, 2008,(04), 953-956
在跟踪弱小运动目标过程中,低信噪比和高虚警率使得即使是在波门内也存在较多的虚假目标,加大目标识
别的不确定性,降低跟踪的可靠性和精度。该文分析了红外成像系统中目标信号特点,根据概率数据关联滤波的
思想,提出了一种基于目标幅度连续性和运动一致性的弱小目标跟踪识别方法,重点比较了极大似然.概率数据关
联滤波和改进算法的目标识别与跟踪性能。理论分析和实验结果表明,该方法较大程度上减少了弱小目标跟踪过
程中测量点与航迹关联的不确定性,提高了目标识别与跟踪性能。
[15]空间 CCD 凝视成像跟踪系统的作用距离分析
董吉辉;胡企铨;, 中国激光, 2008,(02), 173-177
在充分考虑了空间背景光辐射特性以及漫反射目标对相干光和自然光的不同反射特性的基础上,利用信号检
测的统计学方法,导出了空间电荷耦合器件(CCD)凝视成像跟踪系统分别在激光照明主动跟踪模式和太阳光照明
被动跟踪模式下的作用距离表达式。结果表明,空间 CCD 凝视成像跟踪系统在脉冲能量为 1mJ 的激光照明主动
跟踪模式下可对 1m2 空间漫反射目标实现 10km 量级范围内的跟踪;而利用太阳光照明的被动跟踪模式下的跟踪
距离可达几百千米。
[16]TOD 法实现光电成像系统目标识别距离检测
张建辉;耿春萍;陈静;王继光;杨彦杰;, 电子测量技术, 2008,(02), 159-161
光电成像系统多用于对重点区域的监视和重要目标的精确跟踪、定位及引导等,其对目标的跟踪、识别能力
决定了系统的作用范围,因此,对光电成像系统目标识别距离的检测具有重要意义。本文针对光电成像系统性能
测试,就光电靶标设计研究,分析了传统测试方法所存在的问题,提出采用三角方向辨别阈值法,介绍了该方法的基
本思想;根据被测对象,设计靶标结构及测试方法,分析了在特定环境条件下测试使用的结果,并给出试用结论。
光电跟踪
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XIOPM latest Documents Report
光纤激光陀螺
[1]光纤陀螺中光纤环非互易效应及其补偿技术
陈迎丽;谢良平;陈平;严吉中;, 科学技术与工程, 2008,(11), 3059-3063
阐述了影响光纤环性能的主要因素,理论给出温度梯度及应力造成的光纤陀螺非互易相移。详细讨论了减小
温度与应力作用对光纤环影响的技术途径。引入光纤环质量评价方法。
[2]光纤陀螺光纤环 Shupe 效应的三维有限元模型
李茂春;刘铁根;王佳佳;侯丽丽;周友伟;江俊峰;姚晓天;, 天津大学学报, 2008,(05), 601-606
针对传统二维热致非互易光纤环模型的局限性,建立了光纤环柱面坐标三维计算模型,可分析光纤环径向、
轴向和周向温度不均匀变化导致的热致误差速率和热致误差角度.采用有限元方法对光纤环三维物理模型进行数
值仿真,定量分析由温度激励造成的热致误差速率和热致误差角度.开展了光纤环温度激励实验,对比仿真和实验
结果,验证了光纤环三维物理模型的有效性.并将光纤环三维计算模型成功地应用于光纤陀螺(FOG)纤环瞬态特性
检测方法所用的温度激励源设计.
[3]光纤陀螺温度漂移的多变量模型
王俊璞;金志华;田蔚风;, 光电工程, 2008,(05), 66-69
针对光纤陀螺温度漂移的补偿问题,本文提出一种线性多变量光纤陀螺温度漂移建模方法。建立的模型由两
部分组成:陀螺输出的自回归项和温度梯度的多项式分布滞后项(PDL)。自回归项描述光纤陀螺历史输出对当前
输出的影响,PDL 项描述由温度变化引起的陀螺漂移。根据模型的线性特性,采用最小二乘法确定模型参数。用
实测的光纤陀螺温度漂移数据进行了模型的有效性验证。实验结果表明,提出的线性多变量模型能有效补偿光纤
陀螺的温度漂移,补偿后光纤陀螺的精度提高 50%以上。
[4]光纤陀螺“死区”测试分析与建模
潘雄;张春熹;金靖;杨德伟;宋凝芳;, 光电工程, 2008,(05), 61-65
针对采用方波偏置调制、阶梯波反馈调制方案的全数字闭环光纤陀螺"死区"现象的机理进行了实验和仿真
研究。为了考察闭环检测反馈环节对干扰的影响,在开环检测的状态下,叠加了长周期固定台阶高度的数字阶梯
波,得到阶梯波总高度和开环输出之间的相关性,建立了含干扰通道的光纤陀螺开环检测模型。根据形成数字阶
梯波电压大小的等价性,将上述开环模型转换为闭环模型,对闭环简化模型进行了理论分析和仿真计算,并与闭环"
死区"测量曲线进行了对比。实验样机阶梯波电压和开环输出线性相关系数为 0.97,根据开环测得的耦合系数仿
真出的闭环"死区"范围与实验值相差 6.7%。结果表明:干扰随阶梯波电压线性变化是闭环光纤陀螺"死区"产生的
机理之一。
[5]激光陀螺捷联惯导系统中整周期采样的修正研究
严恭敏;严卫生;徐德民;罗毅松;马建伟;, 传感技术学报, 2008,(06), 998-1001
在圆锥运动环境下,若抖动偏频激光陀螺采用整周期采样抖动解调方式,将会引起严重的捷联惯导姿态算法
漂移误差。提出了在整周期采样电路上进行少许改动,就能作出有效改进的方法,并详细推导了线性外推修正的
算法公式。仿真结果表明,当姿态更新采用等效旋转矢量二子样算法时,利用线性+抛物线外推修正的效果非常显
著,它能有效抑制整周期采样造成的姿态算法漂移误差,达到与理想采样的漂移误差非常接近的程度。研究结果
有利于拓展整周期采样的应用范围。
[6]光强干扰调制对光纤陀螺零偏的影响
潘雄;张春熹;宋凝芳;金靖;, 宇航学报, 2008,(03), 912-915+932
方波调制信号是全数字闭环光纤陀螺的基准信号,该信号会通过电源线、地线或以空间电磁场的形式耦合到
光源驱动电路上。基于相干检测原理,推导了由该耦合信号产生的等效相位延迟的计算公式,利用仿真模型估算
了-120dB 耦合强度对不同精度陀螺闭环零偏的影响,利用锁相放大器(LIA)测量了实验电路板上耦合信号的幅值,
证明了该耦合信号与光纤陀螺零偏的相关性。光源驱动电路抗干扰改进后实验样机精度提高了 40%,即 0.14°
/h。结果表明:光源驱动电路中耦合的方波信号是光纤陀螺产生零偏的因素之一,必须在硬件设计或信号处理算法
上加以抑制。
[7]光纤陀螺组合的信号频谱分析与滤波技术研究
刘辉;赵忠;程耀强;, 压电与声光, 2008,(03), 268-271
对某惯导系统中使用的三轴向光纤陀螺(FOG)组合的输出信号做了基于 FFT 的频谱分析,设计并实现了中值
滤波 I、IR 数字滤波器滤波、小波滤波三种不同方法对该信号的噪声滤除,分别给出了滤波后陀螺输出信号的幅
频特性图。通过对试验数据的分析,肯定了三种方法在 FOG 组和输出信号滤波处理中的有效性,并分析了各自的
优缺点。
[8]光纤陀螺寻北仪数据采集单元的设计与实现
任磊;宋凝芳;董全林;, 电子测量技术, 2008,(05), 120-122+147
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针对捷联惯性光纤陀螺寻北仪中惯性器件动态测量范围宽及系统对实时性、可靠性和精度要求高的特点,设
计了基于 FPGA 的高速、多通道、可扩展数据采集单元,实现多传感器数据实时采集。同时,由于用 FPGA 集成
了寻北仪系统主要的 I/O 操作,从而使系统 CPU 能更专注于方位角解算算法,保证了寻北的快速性,并为执行更复
杂的算法提供了有利条件。本文给出了系统软硬件设计方案,实验及实际应用表明,该数据采集单元工作稳定,实
时性好,达到了设计指标。
[9]光纤器件
中国光学与应用光学文摘, 2008,(02), 62-66
[10]小波包变换滤波在光纤陀螺信号降噪处理中的应用(英文)
王其;徐晓苏;, Journal of Southeast University(English Edition), 2008,(01), 46-49
为了减小光纤陀螺仪输出信号中的漂移误差,对小波变换和小波包变换进行了理论分析和比较,建立了光纤
陀螺仪输出信号的数学模型,分析了其输出信号的误差特性,在详细分析比较硬阈值和软阈值小波滤波的基础上,
提出了采用半软阈值作为滤波阈值.并在实验室环境下分别对光纤陀螺静态和动态输出数据进行了半软阈值小波
包滤波实验.对光纤陀螺实时测量信号的实验结果表明:采用半软阈值小波包滤波方法对光纤陀螺仪输出数据进
行处理,静态和动态输出信号误差均方差可以从 5(°) /h 减少到 1(°) /h,有效地消除了光纤陀螺仪中白噪声和分
形噪声的影响.该方法比小波滤波方法更加有效地消除了光纤陀螺漂移误差的影响,且能够满足光纤陀螺仪输出
高精度和实时处理的要求.
[11]光纤陀螺测试系统研究及应用
张延顺;黄萍;李红;, 电子质量, 2008,(04), 1-2+42
利用实验手段来建立光纤陀螺的误差模型并对光纤陀螺进行误差补偿是提高光纤陀螺的一种有效手段。根
据光纤陀螺的特点,设计了光纤陀螺数据采集系统,并做了静态测试和动态测试,分析了光纤陀螺性能,为光纤陀螺
进行误差补偿奠定了基础。
[12]光纤陀螺/GPS 组合导航系统中的信息融合技术
张小跃;张春熹;, 北京航空航天大学学报, 2008,(04), 422-425
光纤陀螺捷联惯导系统用于导航定位具有自主性的优点,但系统误差随时间累积.全球定位系统(GPS,G lobal
Position System)用于导航定位精度很高,误差不随时间积累,但抗干扰性能很差,没有自主性.运用信息融合技术将
光纤陀螺捷联系统和 GPS 进行组合,将 GPS 的高度信息引入惯导高度反馈通道,设定反馈系数,抑制高度发散,将
GPS 经度、纬度、地速信息作为系统卡尔曼滤波器量测信息,消除惯导积累误差.提出的信息融合方案运用于某
中精度光纤陀螺/GPS 组合导航系统并进行路试,导航系统输出 3 个方向位置数据与定位基准相比,误差不随时间
积累,路试结果表明此信息融合方案的有效性及工程的实用性.
[13]基于 SVM 的光纤陀螺标度因数建模研究
王宇;丁萍;吴峻;, 舰船电子工程, 2008,(05), 78-80+128
针对光纤陀螺(FOG)标度因数随温度呈非线性变化的特性,提出采用支持向量机对标度因数进行建模的方法,
以减小光纤陀螺输出误差。利用实验数据对支持向量机对进行训练,获得标度因数的温度模型从而提高 FOG 的
精度。同时将支持向量机对标度因数进行建模的结果与传统的最小二乘建模结果进行比较,验证采用支持向量机
对标度因数建模是非常有效的。
[14]基于 LabVIEW 的光纤陀螺测试分析平台实现研究
凌冬;刘建业;赖际舟;, 测控技术, 2008,(05), 48-51
介绍了一种利用 LabVIEW 构建光纤陀螺测试平台的方法。测试平台通过 RS-232 接口与转台、光纤陀螺相
连,利用 LabVIEW 中的串行通信模块实现对转台运行的控制、状态的读取以及对光纤陀螺数据的采集。利用测
试平台可以对光纤陀螺的输出信号进行积分并与转台位置进行比较,同时可以对光纤陀螺的静态、动态性能进行
分析。
飞秒激光脉冲
[15]飞秒激光诱导 TiO_2 金红石相变的激光显微拉曼光谱研究
陆江;郭青天;马洪良;, 物理实验, 2008,(06), 1-4
利用激光显微拉曼光谱仪研究了近红外飞秒激光脉冲诱导 TiO2 金红石晶体所引起的相变.实验发现当激光
的脉冲功率为 1.0μJ/脉冲时,随着飞秒激光辐照脉冲数的增加,金红石相的 Eg 模式强度增强,而 A1g 模式强度减
弱,飞秒激光的非线性效应在晶体内部诱导产生了色心;当激光辐照脉冲数为 2.5×106 时,锐钛矿石相出现;随着激
光辐照脉冲数的增加,锐钛矿相的拉曼振动模式强度增强,金红石相的拉曼振动模式强度减弱.
[16]飞秒激光微加工技术的评述与展望
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黄佑香;张庆茂;廖健宏;周永恒;, 金属热处理, 2008,(06), 8-13
综述了飞秒激光微加工技术国内外的研究现状,介绍了飞秒激光微加工在光学、微电子及生物医学等领域的
应用,展望了飞秒激光微加工技术未来发展的趋势以及需要解决的关键技术。
[17]飞秒激光与固体靶相互作用中背表面的渡越辐射
王光昶;郑志坚;, 中国激光, 2008,(04), 524-528
在飞秒激光与固体靶相互作用中,利用光学 CCD 相机和光学多道分析仪(OMA),分别在固体薄膜靶背表面法
线方向测量了渡越辐射(TR)积分成像图案和渡越辐射光谱.测量结果显示,渡越辐射光斑呈现圆盘状结构,在圆盘
中明亮而强的光信号呈局部化分布,并且有分离的光斑出现.该现象表明,超热电子在输运过程中存在成丝效应,引
起严重的不稳定性;渡越辐射光谱在 800 nm 附近出现了尖峰,是基频波(ω0),并且光谱向红光方向移动;基频波产
生的原因归结于超热电子束在传输过程中产生的微束团而引起的相干渡越辐射(CTR);光谱红移的原因是由于等
离子体临界面的迅速膨胀所致;渡越辐射光强随靶厚度的增加而减小.
[18]应用于 THz 辐射的 ZnTe 单晶生长及测试
王仍;方维政;赵培;张雷;葛进;袁诗鑫;张惠尔;胡淑红;戴宁;陈晓姝;吴晓君;何山;王钢;, 半导体学报, 2008,(05),
940-943
利用 Te 溶剂方法生长出 ZnTe 单晶.经 X 射线衍射测试,发现晶锭中存在沿〈110〉晶向生长的大晶粒,可以
切出 10mm×10mm 的单晶片.傅里叶红外变换光谱仪测得 ZnTe 晶体在 2.5~20μm 波段的红外透过率约为 61%.
通过测可见-红外波段的透射光谱,得出禁带宽度为 2.24eV.利用飞秒激光作用在一块 ZnTe 单晶同时产生-探测
THz 脉冲,观察到 0.18ps 的 THz 辐射场分布,相应的频谱分布为 5THz.
[19]中国科学院物理研究所在强场物理研究领域取得重要进展
李玉同;张杰;, 科学通报, 2008,(09), 1094
<正>近年来,随着超短脉冲激光啁啾放大(CPA)技术的重大突破,激光强度提高了 5~6 个数量级.利用这种放
大技术建立的激光装置的脉冲宽度可以短至几个光周期(十几飞秒),输出功率可以高达拍瓦(1015W)量级,聚焦光
强超过 1020W/cm2.
[20]飞秒激光器制造亚表面结构
激光与光电子学进展, 2008,(04), 11
<正>德国科学家用一超短波脉冲激光器在蓝宝石晶体中制造亚表面纳米结构,激光照射后选择刻蚀可在蓝
宝石中制造微通道和自组装纳米结构,并能为化学和生物学测量创造微反应器件。以用于制造微流体装置及三维
光子结构。并非用激光器对蓝宝石表面进行直接加工,研究者用在材料表面下产生的高非线性光介质相干超短波
激光脉
[21]飞秒钛宝石激光器的工作原理研究
王志军;逯美红;, 长治学院学报, 2008,(02), 41-45
飞秒激光是一种持续时间极短(10-15s),峰值功率高的以脉冲形式运转的激光。它不仅能使人们获得超短时
间的分辨能力,同时,由于它的高峰值功率,使它在各个领域都得到了广泛的应用。飞秒钛宝石激光器包括飞秒激
光振荡器和飞秒激光放大器两部分,是目前能产生飞秒量级脉冲的应用最广泛的激光器。它通过钛宝石的自锁模
原理,并采用世界上先进的啁啾脉冲放大(CPA)技术,已能直接产生零点几个飞秒、峰值功率达太瓦量级的激光脉
冲。文章从钛宝石晶体的增益特性、自锁模原理、色散及色散补偿、脉冲的展宽与压缩、再生放大器等方面,对
飞秒钛宝石激光振荡器和放大器的工作原理做详细的阐述。
[22]飞秒激光产生与放大技术
陈国夫;程光华;令维军;, 红外与激光工程, 2008,(02), 195-199
介绍了飞秒激光的发展和相关的应用。重点讨论了产生飞秒激光脉冲的几种方法;激光脉冲色散的物理机制
及补偿方法;获得变换极限脉冲的条件等。还介绍了超短超强激光脉冲的放大与压缩技术,获得高功率窄脉冲的
基本条件和啁啾脉冲放大原理;详细地讨论了基于非线性效应实现高信噪比、宽光谱、高效率脉冲放大的光参量
啁啾脉冲放大技术,在飞秒激光脉冲放大中的应用和发展前景。最后还阐述了阿秒光脉冲产生与测量的新技术。
[23]飞秒激光玻璃微加工技术
彭志农;贾威;王清月;, 纳米技术与精密工程, 2008,(02), 114-117
为了研究飞秒激光作用下光学玻璃内部发生的改性过程,利用重复频率为 1 kHz、中心波长为 775 nm、脉宽
为 130 fs 的飞秒激光对光学玻璃进行微加工.结果表明,激光辐照区发生永久性折射率改变,并且玻璃的改性线宽
随着激光功率的增加而增加,随激光扫描速度的降低而增加.根据飞秒激光致使光学玻璃发生改性的特点,利用飞
秒激光在光学玻璃内部直接刻写了相位光栅和二维图案,研究了相位光栅的衍射特性.
[24]钛宝石飞秒激光振荡器的稳定性改善
曹士英;张志刚;柴路;王清月;, 物理学报, 2008,(05), 2971-2975
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对钛宝石飞秒激光器脉冲序列的强度和时间的稳定性进行了分析.实验比较了钛宝石飞秒激光器底板有无水
冷的条件下,输出锁模脉冲序列的稳定性以及中心波长和光谱宽度的变化.结果表明对钛宝石飞秒激光器底板施
加水冷可改善锁模脉冲的稳定性.
[25]高次谐波辐射光子的能量-激光相位关系研究
葛愉成;, 物理学报, 2008,(05), 2899-2905
原子在强激光电场中高次谐波辐射的理论与实验研究是当今科学前沿之一.利用量子力学理论和鞍点方法,
细致地研究了高次谐波辐射光子的能量与激光相位的关系.对于时间宽度无限长激光,在一个激光周期内特定相
位处产生的高阶辐射(X 射线)有特定的能量.能量分布在 71.80°处成峰,有高斯形函数的对称形状.给出了这种分
布的参数化公式.对于不同宽度的飞秒激光,能量分布的成峰位置、最大值和带宽等参数会发生变化.计算表明,三
个振荡周期(半高宽)的飞秒激光,当载波-包络相位为 17.5°和 105°时,可以分别得到纯净的阿秒单脉冲和双脉冲.
在能量-相位图上,基本对称的单脉冲峰位为载波相位 53.86°,宽度 53.34°;高度基本相同的双脉冲峰位分别为31.51°和 143.81°,宽度分别 72.19°和 73.34°,相位间隔 175.33°.这些研究结果,有助于研究超短 X 射线脉冲
的产生、分离、测量和应用.
[26]飞秒激光固体靶相互作用中超热电子的输运特性
王光昶;郑志坚;杨则金;陈涛;张婷;张建炜;, 强激光与粒子束, 2008,(03), 391-395
实验研究了在 100 TW 掺钛宝石超短超强脉冲激光装置上完成的飞秒激光-固体靶相互作用中超热电子的输
运特性,获得了超热电子的能谱、产额、注量及超热电子在靶内输运能量沉积范围。测量结果表明:超热电子的
注量和总能量随靶厚度的增加而减少,超热电子约 80%的能量主要沉积在靶内的前约一个激光脉冲宽度的范围
内,且能量沉积范围随激光脉冲宽度的增加而增加,这主要是静电场的影响所致。
[27]简易自相关仪对飞秒激光脉冲宽度的测量
逯美红;王志军;赵玉连;, 大学物理, 2008,(04), 37-42
用自制的简易自相关仪测量了飞秒的光脉冲宽度,测量结果与理论结果基本一致,并在此基础上分析了一些
实验中的光学器件对飞秒激光脉冲宽度的影响.
[28]利用飞秒激光粉碎病毒
云中客;, 物理, 2008,(04), 259
[29]单脉冲飞秒脉冲激光对单层和高反光学薄膜的损伤
袁磊;赵元安;贺洪波;范正修;邵建达;, 光子学报, 2008,(03), 417-420
用电子束蒸发的方法在 BK7 玻璃上制备了 ZrO2 单层膜和 ZrO2/SiO2 高反膜,利用掺 Ti:sapphire 飞秒激光系
统输出的中心波长为 800nm,脉宽为 50fs 的激光脉冲对这两种样品进行了激光损伤阈值测试.实验结果表明,ZrO2
单层膜的阈值比 ZrO2/SiO2 高反膜的高;这与传统的纳秒脉冲激光的损伤情况相反.利用光离化和碰撞离化激发
电子到导带,形成电子等离子体基本模型并对此现象进行了解释.同时,用显微镜对样品的损伤形貌进行了观测,对
损伤的特点进行了表征.
[30]主动锁模飞秒光纤激光器
宋方;徐文成;申民常;刘颂豪;王可;杨淑雯;, 中国激光, 2008,(03), 347-350
报道了主动锁模飞秒脉冲掺 Er3+光纤激光器的实验结果。在光纤环形腔中通过引入粗波分复用器(CWDM)
作为宽带滤波器,实现了中心波长在 1550 nm,重复频率为 2.5 GHz,谱线 3 dB 带宽为 10.2 nm(对应的脉冲宽度为
247 fs)的激光脉冲输出。此时的抽运功率为 186 mW,激光器输出平均功率为 1.3 mW,从而获得了能够产生飞秒
脉冲的高重复频率主动锁模掺 Er3+光纤激光器。
[31]纳秒激光大气等离子体通道的实验研究
宋述燕;林兆祥;孙奉娄;, 中国激光, 2008,(03), 388-390
为研究激光击穿大气等离子体通道的长度、寿命及导电特性,应用光束整形的方法将 Nd∶YAG 脉冲激光
2.1 J 的能量均匀分布到长度约为 1 m 的直线上,均匀击穿大气,形成等离子体通道。从空间和时间的角度,分别研
究了该等离子体通道的长度、寿命,并使用电学探测手段研究通道的连续导电性。实验结果表明,纳秒激光大气
等离子体通道连续导电的空间长度可达 80 cm 左右,存活寿命在 500 ns 以上,通道的电阻主要由耦合电阻构成。
这些实验结果是飞秒激光大气等离子体通道研究的有益补充,并为大气等离子体通道的应用技术开发提供了实验
依据。
[32]高功率掺镱大模面积光子晶体光纤飞秒激光放大器的实验研究
刘博文;胡明列;宋有建;柴路;王清月;, 中国激光, 2008,(03), 479-480
[33]飞秒激光加工及其应用
罗晓娜;刘金合;唐建宇;, 新技术新工艺, 2008,(02), 48-51+2-3
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综述了激光短脉冲化的飞秒激光发展史,重点论述了飞秒激光的加工机理和特点。飞秒激光独特的光束特性
决定了他是一种理想的微细加工工具,可以实现聚合物的制备,可以对各种透明材料内部进行三维加工和改性,另
外在生物学领域也有着独特的应用。本文最后还展望了飞秒激光加工未来的发展方向。
[34]飞秒激光与晶体材料相互作用的研究进展
孙晓慧;张修丽;刘烈;, 材料导报, 2008,(02), 1-4
综述了飞秒激光与各种晶体材料作用的现象,如双光子、多光子非线性吸收致上转换发光现象,各类微结
构、色心结构等;阐述了飞秒激光与各种晶体的作用机制及在各方面的应用;展望了飞秒激光与晶体材料作用的
应用前景。
[35]测量飞秒激光脉冲啁啾的方法
刘天夫;文汝红;陈碧芳;, 光学与光电技术, 2008,(01), 1-4
介绍了一种能够直接检测飞秒脉冲啁啾大小的方法。采用共轴结构的迈克尔逊干涉自相关二次谐波检测系
统对自制碰撞脉冲锁模循环染料激光器输出的最窄脉冲宽度约为 200 fs 的脉冲进行了测量。测得的飞秒脉冲自
相关二次谐波曲线表明:实测曲线的下包络两翼明显隆起,包络外形很不整齐,对称性较差,说明光脉冲含有啁啾。
通过比较干涉测量曲线和理论曲线的形状与面积的大小,可以直观地反映出光脉冲所含啁啾的大小。实验结果分
析表明,利用满足光相关检测所需精度的光学元件和满足光相关探测基本条件的实验装置,能测得含有相位及啁
啾信息的快干涉项信号,是一种能够直观检测光脉冲所含啁啾大小的可行方法。
成像光谱
1]新型偏振干涉成像光谱仪中格兰-泰勒棱镜像质分析与评价
吴海英;张淳民;赵葆常;, 物理学报, 2008,(06), 3499-3505
阐述了自行研制的新型偏振干涉成像光谱仪中重要偏光器件格兰-泰勒棱镜的分光机理,应用光线追迹法分
析计算了光在格兰-泰勒棱镜中的传播规律与光线轨迹;推导出了任意角度入射时光线在棱镜中的传播方向及出
射点坐标;给出了格兰-泰勒棱镜的像点位移和色差理论计算公式.该研究对晶体器件像质的分析计算及评价具有
普遍的指导意义,为新型偏振干涉成像光谱技术的研究以及偏振干涉成像光谱仪的研制提供了重要的理论依据.
[2]干涉成像光谱仪切趾函数对复原光谱的影响分析
张文娟;张兵;张霞;高连如;张维;, 红外与毫米波学报, 2008,(03), 227-232+240
随着搭载干涉成像光谱仪 HJY20-1-A 的我国环境与减灾遥感卫星 HJ-1A 即将发射,我国干涉光谱成像研究
也从实验室开始走向实用化.在干涉光谱成像过程中,切趾函数处理是干涉成像光谱仪光谱复原过程中的一个重
要环节,对复原光谱的精度有着极其重要的影响.根据 HJY20-1-A 的参数设置,文中首先模拟了 24 种典型地物对
应于 HJY20-1-A 和其它最大光程差设置的干涉成像光谱仪数据,在不同切趾函数作用下的复原光谱,结果表明
Hann ing 函数是其中最有效、最为稳定的切趾函数,同时发现切趾函数的应用虽然可以提高复原光谱的精度,但
与真实光谱仍存在一定差距,尤其对应 HJY20-1-A,复原光谱的精度更加有限.在以上分析基础上,提出了基于仪器
线型函数标准化的光谱复原改进算法,实验结果证实了该方法可以显著提高复原光谱精度,尤其适用于最大光程
差较小的空间调制型干涉成像光谱仪.最后,就 HJY20-1-A 复原光谱对 3 种典型植被指数求解,进一步证明了该方
法的有效性.
[3]激光等离子体 X 射线极化光谱研究
王洪建;肖沙里;施军;唐昶环;刘慎业;钱家渝;, 光学精密工程, 2008,(05), 822-826
研制了一种新型的基于空间分辨的激光等离子体 X 射线极化谱仪。将平面晶体和球面弯晶色散元件在极化
谱仪内正交布置,即在水平通道用 PET 平面晶体作为色散元件,在垂直通道用半径为 380 mm 的 Mica 球面弯晶作
为色散元件。信号采用成像板进行接收,有效接收面积为 30 mm×80 mm,从等离子体光源经晶体到成像板的光
路为 980 mm。实验中成像板获得了铝激光等离子体 X 射线的光谱空间分辨信号。实验结果表明:该极化谱仪具
有较高的光谱分辨率,适用于激光等离子体 X 射线极化光谱的诊断。
[4]基于显微高光谱成像的人血细胞研究
李庆利;肖功海;薛永祺;张敬法;, 光电工程, 2008,(05), 98-101
使用自行研制的推帚式显微高光谱成像系统采集了正常、白血病人血液涂片的显微高光谱图像数据。通过
对正常、白血病人血液显微高光谱数据进行处理,获得了人血液的单波段图像,并提取了部分血液细胞的典型透
射率光谱曲线。分析这些曲线发现,病变细胞透射率普遍高于正常细胞,特别是在 541.3nm 附近透射率高出了
50%左右。通过对血液涂片的图像和光谱特征进行分析表明,经过一定的改进,可以将显微高光谱成像系统作为
一种新的检测手段,辅助医学研究人员对人血液进行分析。
[5]基于 FPGA 的超光谱成像仪数据采集系统设计
何海波;谢惜惜;王跃明;刘银年;, 科学技术与工程, 2008,(12), 3309-3312+3316
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基于 FPGA 设计了一套数据采集系统,实现某超光谱成像仪研制过程中的光谱图像数据的采集、传输、显示
与存储。该设计综合应用了 FPGA、USB、LVDS、时钟数据恢复、8B/10B 编码、乒乓缓存等技术,具有高速
率、低功耗、小型化和轻量化等特点,对类似数据采集系统的设计具有参考和借鉴意义。
[6]基于 CCD 的双光束多波长紫外可见吸收检测器
申爽;唐祯安;李彤;, 仪器仪表学报, 2008,(05), 1069-1072
由于传统的多波长紫外可见吸收检测器无法克服光源波动造成的噪声和漂移,故设计开发了一种基于 CCD
的双光束多波长紫外可见吸收检测器。光源发出的光聚焦后被分束镜分成信号光和参考光,信号光射入到样品检
测池中。从样品检测池中出射的信号光经过斩光器聚焦在狭缝上,被凹面光栅分光成像于 CCD 的一部分光敏面
上。参考光在 CCD 的另一部分光敏面上分光成像。在光路系统和外围电路的辅助配合下,可以用一片 CCD 实现
信号光谱,参考光谱和暗电流的精确测量。由于采用参考光光谱和 CCD 暗电流对信号光谱进行实时补偿,可以使
基线短期噪声降低为 1×10-5AU,漂移降低为 1×10-4AU/h。
[7]可编程光谱成像系统
高;, 红外, 2008,(05), 36
<正>美国专利 US7342658 (2008 年 3 月 11 日授权)本发明提供一种用以从一个目标获取光谱图像数据的可
编程光谱成像系统。该成像系统包括一个光源、
[8]太赫兹成像系统及相关方法
高;, 红外, 2008,(05), 9
<正>美国专利 US7342230 (2008 年 3 月 11 日授权)本发明提供一种太赫兹成像系统,它是利用一个太赫兹光
源以一连串短太赫兹光脉冲照射目标的。这些脉冲的平均输出功率较低,但峰值输出功率较高,因而能使该成像
系统在安全的距离内对可疑的物体或人进行
[9]干涉图采样和数据处理的仿真研究
吴娜;向阳;, 微计算机信息, 2008,(10), 237-238
结合静态干涉成像光谱仪工作原理,建立了干涉图空间采样的数学模型,利用 Matlab 软件实现了干涉图采样
和数据处理的计算机仿真研究。该仿真平台可比较不同采样过程和不同数据处理方法对复原光谱的影响,对静态
干涉成像光谱仪的设计和性能分析有一定指导意义。
[10]基于高光谱成像技术的中医舌象辅助诊断系统
李庆利;薛永祺;刘治;, 生物医学工程学杂志, 2008,(02), 368-371
中医舌诊是传统中医的一种重要诊断方法。由于舌诊是一种定性的、主观的和基于经验的诊断方法,从而制
约了中医舌诊在临床医学上的广泛应用。针对中医舌诊现代化中存在的问题,开发研制了一种基于高光谱成像技
术的舌象辅助诊断系统。这一系统包括高光谱舌图像采集、图像存储、特征提取和辅助诊断几部分。系统使用
高光谱成像技术代替通常使用的数码相机进行舌图像采集,并对高光谱舌图像进行了图像和光谱特征提取,然后
使用贝页斯分类器初步建立起了舌象特征与病症之间的联系,最后通过初步试验证明了这一系统的有效性。
[11]有孔探针近场拉曼光谱和成像技术进展
江洋;任斌;田中群;, 光谱学与光谱分析, 2008,(05), 1080-1090
基于有孔探针 SNOM 的近场拉曼光谱和成像技术的出现使得拉曼光谱的分辨率突破了光学衍射极限,从而
提供了一个有力的工具对样品亚波长尺度之下的化学信息进行表征。文章讨论了探针性质对实现近场拉曼光谱
的影响,并全面地介绍了有孔探针近场拉曼光谱发展十余年来在纳米尺度化学分辨成像、液-液界面性质研究、
微观层面解释 SERS 增强机理、图像化反映 SERS 热点分布等诸多领域的研究进展。
[12]光谱仪器
中国光学与应用光学文摘, 2008,(02), 19-20
[13]基于多通道窄带滤波阵列的微型多光谱成像仪
叶玉;张涛;郑伟波;王少伟;, 科学技术与工程, 2008,(08), 1989-1993
设计出一种基于多通道窄带滤波阵列的微型多光谱成像仪。系统根据推帚式成像光谱仪的原理进行设计,采
用多通道窄带滤波阵列在后光学系统进行分光,利用高精度载物台驱动实验目标进行推扫成像,选用 USB 总线作
为数据采集的微机接口。整个系统由宽光谱光源、普通光学镜头、分光滤波片、面阵 CCD 成像装置、载物台
自动装置以及数据采集和控制模块等几部分组成。系统的光谱范围从 760nm 到 900nm,共 16 个波段,光谱分辨率
<10nm。系统具有同时获取不同波长光谱信息、结构紧凑、成本低、可靠性强和小型化等优点;不仅能够提供目
标在近红外的单波段光谱图像,而且能够获得图像中任意像素的光谱曲线,实现光谱技术和成像技术的结合。
[14]台湾海峡 MERIS 数据大气校正研究
陈芸芝;汪小钦;高中灵;, 海洋科学, 2008,(03), 62-67
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根据 MERIS(Medium Resolution Imaging Spectrometer,中等分辨率成像光谱仪)L1B 产品特点,以台湾海峡为
研究区域,开展 MERIS 数据大气校正研究。在阐述水色遥感数据大气校正原理的基础上,首先进行水体像元提取
和辅助参数空间内插,获取大气校正所需的数据集。接着进行耀斑反射率计算和校正并利用加倍法精确计算瑞利
散射。最后针对台湾海峡水体为清洁到轻度浑浊,提出先区分水体类别,再分别利用 epsilon 指数外推法进行一类
水体气溶胶散射计算,和利用神经网络法计算二类水体离水反射率即ρw 的方法。对大气校正的结果进行ρw 负
值像元数统计和光谱分析表明,该方法不仅降低ρw 为负值的像元数,而且使大气校正后水体的光谱曲线同现场
数据保持较好的一致性。
[15]多角度成像光谱辐射仪在大气污染研究中的应用回顾
刘阳;陈丹;Ralph A.Kahn;贺克斌;, 中国科学(D 辑:地球科学), 2008,(03), 384-396
美国宇航局于 1999 年底发射的多角度辐射成像光谱仪(MISR)采用了独特的多角度观测设计,将 9 台相机沿
卫星航迹方向按照固定角度排列并同时采集反射光.这种设计使其具备了当前其他星载气溶胶遥感设备不具备的
在陆地和海洋上空反演包括气溶胶浓度、形状以及组分的多种特性的能力.由于对细颗粒物非常敏感,MISR 为研
究区域颗粒物空气质量的时空分布特性提供了新的数据来源.首先简要介绍 MISR 设备、它的气溶胶反演算法及
数据结构,然后综合论述了目前 MISR 气溶胶数据在空气质量研究方面的应用状况包括在污染事件(例如沙尘、
火灾以及城市空气污染)中对颗粒物空间分布的观测.MISR 高质量的气溶胶数据可以作为颗粒物浓度的定量指标,
回顾了目前在估算地面颗粒物浓度方面的研究成果,介绍了使用 MISR 高级数据对烟尘高度以及颗粒物成份的研
究.由于中分辨率成像光谱仪(MODIS)的气溶胶数据在中国有较广泛的使用,讨论中尽可能的与之进行了比较.最
后总结了 MISR 数据在空气质量研究中的优点与不足.相信 MISR 反演的丰富的高度定量化的气溶胶数据对研究
中国空气质量问题具有很大的应用价值.
[16]基于 USB 的超光谱成像仪数据采集系统的设计
何海波;谢惜惜;王跃明;刘银年;, 红外, 2008,(05), 18-23+45
设计了一套基于 USB 2.0 高速串行总线的数据采集系统,实现了某超光谱成像仪研制过程中的光谱图像数据
采集、传输、显示与存储。系统的软硬件设计综合应用了 USB、LVDS、时钟数据恢复、8B/10B 编码、乒乓缓
存、多线程和 DirectDraw 等技术.相对于传统的基于 ISA/PCI 总线的成像光谱仪数据采集系统,该设计支持热插
拔和总线供电,具有低功耗、小型化和轻量化等特点,对类似数据采集系统的设计具有参考和借鉴意义。
[17]超光谱成像仪狭缝热光谱特性的分析
李泽学;吴清文;颜昌翔;陈立恒;訾克明;, 光学技术, 2008,(03), 437-440
介绍了在狭缝超光谱成像仪中的重要作用。推导出在温度水平变化时,狭缝宽度尺寸的变化对超光谱成像仪
光谱带宽与信噪比的影响,得到了超光谱成像仪狭缝的热光谱特性。比较了两类常见狭缝的热光谱特性,得出热
特征尺寸与其导热率乘积越小的狭缝热光谱特性也越好的结论。
[18]基于液晶滤光器的连续光谱成像测试装置
赵静;庞其昌;马骥;郑茜文;孟庆霞;, 光子学报, 2008,(04), 758-762
为了使普通光学采集设备同时获得样品光学形态和成份信息,设计了一种可以实现连续光谱成像的测试装置.
系统采用电可调液晶滤光器作为分光器件,低照度面阵 CCD 作为接收器,光谱分辨率可达到 0.5nm,无需传统光谱
成像仪中的机械推扫装置.在系统设计中,软件设计目的在于能够实现数据采集控制和后台数据处理等功能.对系
统的工作参量进行了测试,给出了系统透过率函数和线性工作范围.为了检测设备工作的稳定性,对低压汞灯和氦
氖激光器的光谱进行了检测,给出了多次测试结果的标准误差.最后对中药黄连的活性成份盐酸小檗碱进行了在
体检测,通过确定光谱特征,可得到其空间分布信息.
[19]光谱学与光谱技术
中国光学与应用光学文摘, 2008,(02), 12
[20]球面弯晶分析器研制
施军;肖沙里;王洪建;唐昶环;刘慎业;, 重庆大学学报, 2008,(04), 397-400
在激光聚变实验中为了获取等离子体的重要信息,采用球面弯曲晶体成像谱仪来研究等离子体辐射的 X 射
线,利用球面弯晶对 X 射线进行诊断而提供时间、空间、光谱分辨。该强聚焦晶体能增强信噪比,提高谱仪的空
间分辨能力及立体角收集辐射能力。实验结果表明球面弯晶分析器对波长范围为 0.2~0.4 nm 的 X 射线其分辨率
可达 600~1 000,聚光效率在同样距离条件下比平晶分析器高一个数量级以上,适合于研究等离子体 X 射线光谱
学。
[21]显微高光谱成像的生物组织定量检测机理及方法研究
李庆利;薛永祺;肖功海;张敬法;, 科学通报, 2008,(04), 493-496
将显微镜技术与高光谱成像技术相结合,研制出了推帚式显微高光谱成像系统.介绍了系统原理和实现的关
键技术,并对系统的性能进行了分析.对显微高光谱数据的预处理方法进行了研究,提出了一种利用空白显微高光
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谱图像进行光谱响应校正的算法.对校正后的数据进行了归一化处理,反演出了生物组织的透射率光谱曲线.使用
该系统采集了大鼠视网膜组织切片的显微高光谱数据,获得了视网膜切片的单波段图像和 3 波段伪彩色合成图像,
并提取出了透射率光谱曲线.初步试验表明,显微高光谱成像系统在生物样本的检测和分析中具有良好的应用前
景.
[22]风云卫星遥感数据高精度地理定位软件系统开发研究
杨忠东;关敏;, 遥感学报, 2008,(02), 312-321
为了适应风云气象卫星遥感数据高精度地理定位要求,在研究和比较分析现有环境气象卫星遥感数据地理定
位方法,尤其对其中关键的轨道计算模型进行对比研究之后,我们使用变阶变步长多步卫星轨道数值计算模型
(DE/DEABM)进行气象卫星轨道计算,研制开发了新一代卫星轨道计算及遥感数据地理定位软件系统。该软件系
统中卫星轨道数值积分计算模型包含了多项摄动因素计算,特别是对低轨卫星影响较大的因素,其中地球的球形
引力项使用了高精度高阶 EGM-96 地球引力场模型,提高了非球形引力摄动计算精度,另外还考虑了太阳、月亮
引力项,辐射光压摄动和大气摄动因素,使得轨道计算精度大大提高。在遥感数据定位算法开发工作中,以中国
2002 年 5 月发射的风云 1 号 D 星 10 通道扫描辐射计和计划 2008 年上半年发射的风云 3 号 A 卫星中分辨率光谱
成像仪等遥感仪器为对象,比较详细地分析和研究了探测器、焦平面、主光学系统和扫描镜等遥感仪器几大关键
部件的光学几何关系,提高了坐标转换系统计算精度。经过对风云 1 号 D 星多天逐日的轨道计算和定位计算试
验,结果表明该软件系统 24h 风云 1 号 D 星轨道计算卫星矢径精度可达到几十厘米至几十米,较原来平根数分析
解方法 1000m 左右精度有显著量级的提高。同时,风云 1 号 D 星遥感数据地理定位精度达到星下点 1 个像元。
[23]基于面阵 CCD 的 MAX-DOAS 系统性能研究
张英华;谢品华;司福棋;林艺辉;彭夫敏;李素文;李昂;窦科;朱燕舞;, 大气与环境光学学报, 2008,(02), 134-138
介绍了自制的地基多轴差分吸收光谱系统,该系统采用二维面阵 CCD 探测器,将不同水平仰角所接收的光信
息分布在面阵 CCD 的不同区域,实现了对不同水平仰角痕量气体的同时测量,并对系统中面阵 CCD 探测器的偏
置、暗电流、噪声、响应线性以及成像光谱仪的分辨率、光谱范围等性能进行了测试。给出了该系统对不同观
测水平仰角下大气 O_3 的监测结果,结果表明此多轴差分吸收光谱系统能够满足大气监测的要求。
[24]卫星干涉多光谱图像压缩新算法
王柯俨;吴成柯;孔繁锵;马静;, 光子学报, 2008,(03), 555-560
根据卫星干涉多光谱图像的成像特性,提出一种基于分类权值率失真优化截取和自适应编码深度控制的部分
SPIHT 光谱图像压缩算法.首先根据干涉区域类型和编码平面的重要性,对各棵零树各个编码过程赋予不同的重
要性权值,然后采用部分 SPIHT 算法对每棵零树独立编码,编码时根据比特平面层中重要系数的统计概率自适应
地进行 3 种编码模式的选择,同时依据重要性权值和深度控制因子自适应地控制每棵零树的编码深度,最后在编
码深度内,根据不同干涉区域的零树对恢复光谱的失真贡献,采用分类权值率失真方法对码流进行优化截取,使码
流分配与失真达成最优.实验结果表明,本算法比传统算法更好地保护了光谱信息.
[25]傅里叶变换成像光谱数据压缩
吕群波;袁艳;相里斌;, 光子学报, 2008,(03), 573-576
通过对傅里叶变换成像光谱仪数据的高低频反演光谱与光程差间的关系进行分析,提出一种光谱插值预测与
量化编码压缩方法.仿真结果表明,在相对光谱二次误差<1%的情况下,压缩比优于 5∶1.
[26]太赫兹逐点扫描计算机成像算法
张燏;张建林;姜常胜;, 计算机工程与应用, 2008,(11), 234-236
利用本校率先在国内建立起的一套具有较高应用价值的透射式逐点扫描太赫兹(THz)辐射成像装置可以获
得成像物体上每一点的光谱数据。每一点的光谱数据对应一个文本文件,这些数据虽具备物理含义,但本身不具
备图像数据的特征。根据太赫兹振幅成像的实际物理意义,提出了一种根据成像物体上每一点的光谱数据,在计
算机上构造太赫兹振幅图像的算法。实验证明,该算法取得理想的效果,对 THz 成像技术和 THz 光谱分析的研究
具有一定的意义。
[27]LAMOST 焦面板数学建模与仿真
蒋晓魁;王建平;李晓峰;刘志刚;, 计算机仿真, 2008,(03), 100-103+114
焦面板是大天区面积多目标光纤光谱天文望远镜的一个重要部件,它是一个球面孔群结构,孔的位置精度直
接影响到系统的成像质量。建立焦面板孔群中心点位置的数学模型并进行仿真不仅是进行优化孔群分布的需要,
也是进行后续数控加工的需要。空间球坐标投影算法,解决了在球面上近似均匀分布孔群的难题,并利用科学计
算工具 MATLAB 进行了数学建模与仿真。最后给出了仿真结果和孔群中心点位置的三维坐标,并提出了其他的
改进方案。结果表明,该算法能有效地提高焦面板的孔位精度,满足了 LAMOST 的需要。
[28]红外成像制导反舰导弹模块化数字仿真
彭星光;高晓光;, 火力与指挥控制, 2008,(03), 28-30+34
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模块化仿真可将整个复杂大系统划分为若干子模块,分别对各个模块进行仿真,使得整个仿真过程变得简便
易行;另外,其面向对象性质可使整个系统更具灵活性和可移植性。将模块化仿真思想用于红外成像制导反舰导
弹的仿真中,实验结果证明该方法是可行有效的。
[29]像元光敏宽度对干涉成像仪复原光谱幅值的影响
吴娜;向阳;, 光学技术, 2008,(02), 246-248
推导出了静态干涉成像光谱仪的探测器阵列采样空间调制干涉图的实际数学表达式,由此进一步推导出了含
像元光敏宽度的复原光谱幅值的一般表达式。分析结果表明,当像元间距一定时,光敏宽度对复原光谱幅值存在
影响。对于确定的光敏宽度,随着波数的变长,复原光谱幅值所受到的影响逐渐增大;对于确定的波数,随着光敏宽
度的变宽,复原光谱幅值所受到的影响逐步增大。
[30]姿态倾斜对时-空联合调制型干涉成像光谱仪成像质量的影响
赵慧洁;贾国瑞;, 光学学报, 2008,(03), 583-586
时-空联合调制型干涉成像光谱仪获取的像面干涉图是带有干涉条纹的二维空间图像,具有对姿态变化敏感
的特点。根据该类仪器的成像过程,在竖直摄影时,相邻两帧像面干涉图之间的像移量为一列像元;偏离竖直摄影
时,由于像面干涉图的几何变形或旋转,会引入非正常像移。利用共线方程导出了这一非正常像移量的表达式。
利用仿真计算说明:这一非正常像移会在像面干涉图序列中不断积累,导致提取出的物体干涉信息失真。在竖直
摄影而平台指向精度较低、倾斜摄影、探测器阵列的安装方向精度较低或者航空成像且存在偏流角时,必须对像
面干涉图进行有效校正,才能保证最终反演出的物体光谱的真实性。
太阳能电池
[1]太阳能电池供电系统在微波中继站的简化设计
王西林;, 内蒙古科技与经济, 2008,(08), 206
根据太能电池应用系统所处的地理位置和气象条件的不同,提出了太阳能电池方阵总功率的简化设计计算,
并通过太阳能电池供电系统设计的实例进行了论证。
[2]太阳常量和太阳能电池的发电功率
金仲辉;, 中学生数理化(八年级物理)(人教版), 2008,(03), 61
<正>太阳能电池可以提供清洁的能源,它越来越受到人们的重视.如果要问及太阳能电池的发电功率,可能许
多人是难以说清楚的.
[3]有机染料敏化纳米晶太阳能电池
郑冰;牛海军;白续铎;, 化学进展, 2008,(06), 828-840
本文综述了有机染料敏化纳米晶太阳能电池的研究现状,简要介绍了有机染料敏化纳米晶太阳能电池的结构
和工作原理以及氧化物电极、对电极和电解质的设计思路和制备情况。重点介绍了有机染料的研究现状,包括香
豆素类染料、多烯类染料、噻吩类染料、天然染料、半花菁类染料、卟啉类染料、三苯胺类染料、
等。同时讨论了若干影响有机染料敏化太阳能电池性能的因素,提出了提高光电转换效率的设想与对策,对未来
的发展进行了展望。
[4]国产染料敏化太阳能电池光电转化率超过 10%,接近世界最高水平
今日电子, 2008,(06), 53
<正>华东师范大学科研人员利用纳米材料在实验室中成功研制出一种与叶绿体结构相似的新型电池——染
料敏化太阳能电池,经过 3 年多实验与探索,这块仿生太阳能电池的光电转化效率已超过 10%,接近 11%的世界最
高水平。
[5]新型太阳能电池——染料敏化太阳能电池研制进展
本刊编辑部;, 物理通报, 2008,(05), 1
[6]基于太阳能电池的低功耗数据终端的设计
傅仁轩;陈龙飞;, 现代电子技术, 2008,(10), 49-51
提出一种基于太阳能电池的低功耗数据终端的设计方案,实现无交流电场合的数据监测与控制。设计方案采
用软硬件相结合,硬件以 MSP430 处理器为核心,软件以 IAR Embedded Workbench 为开发环境,用 C 语言编写应
用程序。通过长时间的测试和现场使用,证明本低功耗数据终端设计的可行性,具有进一步推广应用的价值。
[7]染料敏化纳米薄膜太阳能电池的研究进展
姜黎明;, 科技信息(科学教研), 2008,(15), 30
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染料敏化纳米薄膜太阳能电池(DSSC)是一种新型的太阳能电池。介绍了染料敏化纳米薄膜太阳能电池的结
构和工作原理,并对其组成要素如多孔纳米膜、光敏化染料、电解质、对电极等的研究进展进行了简述。同时对
染料敏化纳米薄膜太阳能电池的发展进行了展望。
[8]华东师大染料敏化太阳能电池获得高光电转化效率
光机电信息, 2008,(05), 49-50
<正>植物体内神奇的光合作用,有望助人类实现清洁能源的梦想。日前,华东师范大学的科研人员利用纳米
材料在实验室中成功"再造""叶绿体",以极其低廉的成本实现光能发电。
[9]太阳能电池检测系统基本原理
崔容强;王晨;, 阳光能源, 2008,(03), 36-40
21 世纪,随着工业发展和居民生活水平提高,各种环境问题日益显现,其中最主要的污染源是煤炭、石油燃烧
后的二氧化碳,它将引起全球变暖,气候剧变,为了减少二氧化碳的排放量,各种环保零排放能源相继开发,如风能,
水力发电,太阳能等等。太阳能作为环保能源之一,有着许多优势:占用场地小,可以利用屋顶,高楼大厦的窗,戈壁
沙漠,或者是宇宙空间。太阳能电池的生产需要相当多的工序,而检测又是必不可少的一个环节,检测过程将筛选
出物理性能相当的太阳能电池片,之后将匹配的电池片组装成电池组件板,许多电池组件板配上相关设备就可作
为发电单位,在有阳光的环境下由光能转化成电力。
[10]太阳能电池产能利用率不到 60%
通信电源技术, 2008,(02), 55
[11]纳米技术提升太阳能电池竞争力
能源工程, 2008,(02), 30
[12]美国研制出超薄太阳能电池
魏利;, 农村电工, 2008,(05), 45
<正>据报载,一种可"印"在铝箔上的超薄太阳能电池日前在美国加利福尼亚州一家工厂的流水线上源源不断
地生产出来。这种可以大规模生产的太阳能电池被科学家称为太阳能发电的"革命"。
[13]纳米晶可编织纤维太阳能电池研究
纳米科技, 2008,(02), 77
<正>北京大学化学与分子工程学院邹德春教授领导的研究小组在近期开展的系列工作中,充分利用纳米结
构独特的光学以及电子学特性,采用与传统太
[14]体异质结有机太阳能电池性能提高的研究
苏梦蟾;衣立新;汪洋;时玉萌;梁春军;, 光谱学与光谱分析, 2008,(04), 740-744
制备了四种不同结构的有机太阳能电池器件,器件 1ITO/LiF/PEDOT∶PSS/MEH-PPV/C60/Al、器件
2ITO/PEDOT∶PSS/MEH-PPV/C60/Al、器件 3ITO/LiF/PEDOT∶PSS/MEH-PPV∶C60/C60/Al 和器件
4ITO/PEDOT∶PSS/MEH-PPV∶C60/C60/Al。测量了它们的电流-电压特性,结果显示在 ITO 和 PEDOT∶PSS 之
间插入一薄层 LiF 使得器件性能得到较大提高。其器件 1 的 JSC 和 FF 比器件 2 的提高了 74%和 31%;器件 3 的
JSC 比器件 4 的提高了约 40%。这主要是由于 LiF 层有效地抑制了空穴向阳极的传输,并且 LiF 层在 ITO 和
PEDOT:PSS 之间形成了良好的界面特性。因此,这种结构上的改进有效地提高了有机太阳能电池的性能。
[15]CIS 薄膜太阳能电池 Cu-In 前驱膜结构相变研究
阎有花;刘迎春;方玲;赵海花;李德仁;卢志超;周少雄;, 稀有金属, 2008,(02), 156-160
为考察 CIS 薄膜太阳能电池 Cu-In 前驱膜结构相变规律,采用电沉积法制备 Cu-In 前驱膜,并对前驱膜进行真
空退火热处理。采用 SEM 和 EDS 观察并分析了薄膜的表面形貌和成分,采用 XRD 表征薄膜组织结构。结果表
明,Cu-In 前驱膜以 CuIn,CuIn2 和 Cu 混合相存在;157℃真空退火 10min,发生第一次相变生成 Cu11In9 相;310℃真
空退火 10min,发生第二次相变生成 Cu7In3 相。富 Cu 的 Cu-In 前驱膜结构相变受动力学边界条件所控制。
[16]硅太阳能电池串联电阻的一种估算新方法
廖志凌;阮新波;, 电工技术学报, 2008,(05), 88-92
硅太阳能电池等效串联电阻会影响其正向伏安特性和短路电流,而对开路电压没有影响,另外串联电阻的增
大会使太阳能电池的填充因子和光电转换效率降低。研究计算太阳能电池串联电阻具有重要的实际意义。提出
一种估算太阳能电池串联电阻的新方法,利用太阳能电池生产厂商提供的在标准测试条件下的四个技术参数(短
路电流 Isc,开路电压 Voc,最大功率点电流 Im 和电压 Vm)进行计算,同时通过引入相应补偿系数来考虑太阳光强
和电池温度变化时对串联电阻的影响。理论估算结果与实验测量结果比较,两者误差在工程应用允许的精度 6%
以下。
[17]掺杂室沉积本征微晶硅材料及其在太阳能电池中的应用(英文)
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孙福河;张晓丹;赵颖;王世峰;韩晓艳;李贵军;魏长春;孙建;侯国付;张德坤;耿新华;熊绍珍;, 半导体学报, 2008,(05),
855-858
在掺杂 P 室采用甚高频等离子体增强化学气相沉积( VHF-PECVD)技术,制备了不同硅烷浓度条件下的本征
微晶硅薄膜.对薄膜电学特性和结构特性的测试结果分析表明:随硅烷浓度的增加,材料的光敏性先略微降低后提
高,而晶化率的变化趋势与之相反; X 射线衍射( XRD)测试表明材料具有(220)择优晶向.在 P 腔室中用 VHFPECVD 方法制备单结微晶硅太阳能电池的 i 层和 p 层,其光电转换效率为 4.7 %,非晶硅/微晶硅叠层电池(底电池
的 p 层和 i 层在 P 室沉积)的效率达 8.5 %.
[18]太阳能电池制造大国有产能无市场人大代表“开药方”
电源技术, 2008,(04), 203
<正>这是一笔巨大的节能"反差账":2007 年,我国太阳能电池产能约占全球市场的 16.7%;而年度光伏发电量
不仅落后于水电、火电,也落后于同时起步的风力发电。"我国的太阳能电池产能没有完全发挥出来,关键在于国
内光伏发电的消
[19]我科学家研制出仿生太阳能电池光电转化率接近世界最高水平
光学仪器, 2008,(02), 74
[20]太阳能电池用高温烧结炉传动系统的设计计算
陈特超;, 电子工业专用设备, 2008,(04), 10-13
介绍了太阳能电池生产线用高温烧结的特点、传动原理,提出了网带驱动力及其传递功率的理论计算方法,
利用该方法进行设计计算,可在保证传动可靠的前提下,选择最合适的电机、减速机,减少安装位置,节约设备制造
成本。作者根据计算结果应用到实际的生产中,较好的指导了生产。
Femtosecond and Attosecond Pulse
Record 1 of 30
Author(s): Couairon, A (Couairon, Arnaud); Chakraborty, HS (Chakraborty, Himadri S.); Gaarde, MB (Gaarde, Mette
B.)
Title: From single-cycle self-compressed filaments to isolated attosecond pulses in noble gases - art. no. 053814
Source: PHYSICAL REVIEW A, 77 (5): 3814-3814 Part B MAY 2008
Abstract:
We investigate numerically the recently proposed technique of pulse self-compression by filamentation in noble gases.
We show that propagation of a 30 fs infrared pulse containing a few mJ of energy leads to a few-cycle pulse in xenon,
krypton, argon, and neon. We describe the different mechanisms and stages of self-compression in the different gases
and show that neon, with the highest ionization potential, allows compression to the shortest durations and highest peak
intensities. We discuss the process by which an unavoidable frequency modulation of the self-compressed filament
simultaneously allows the generation of isolated attosecond (as) pulses via high-order harmonic generation and limits
the conversion efficiency of the as pulses.
-------------------------------------------------------------------------------Record 2 of 30
Author(s): van Tilborg, J (van Tilborg, J.); Toth, C (Toth, Cs.); Matlis, NH (Matlis, N. H.); Plateau, GR (Plateau, G. R.);
Leemans, WP (Leemans, W. P.)
Title: Single-shot measurement of the spectral envelope of broad-bandwidth terahertz pulses from femtosecond electron
bunches
Source: OPTICS LETTERS, 33 (11): 1186-1188 JUN 1 2008
Abstract:
We present a new approach (demonstrated experimentally and through modeling) to characterize the spectral envelope
of a terahertz (THz) pulse in a single shot. The coherent THz pulse is produced by a femtosecond electron bunch and
contains information on the bunch duration. The technique, involving a single low-power laser probe pulse, is an
extension of the conventional spectral encoding method (limited in time resolution to hundreds of femtoseconds) into a
regime only limited in resolution by the laser pulse length (tens of femtoseconds). While only the bunch duration is
retrieved (and not the exact charge profile), such a measurement provides a useful and critical parameter for
optimization of the electron accelerator. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 3 of 30
Author(s): Morohashi, I (Morohashi, Isao); Sakamoto, T (Sakamoto, Takahide); Sotobayashi, H (Sotobayashi,
Hideyuki); Kawanishi, T (Kawanishi, Tetsuya); Hosako, L (Hosako, Lwao); Tsuchiya, M (Tsuchiya, Masahiro)
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Title: Widely repetition-tunable 200 fs pulse source using a Mach-Zehnder-modulator-based flat comb generator and
dispersion-flattened dispersion-decreasing fiber
Source: OPTICS LETTERS, 33 (11): 1192-1194 JUN 1 2008
Abstract:
By combining a Mach-Zehnder-modulator-based flat comb generator (MZ-FCG) with a dispersion-flattened dispersiondecreasing fiber, femtosecond pulses have been generated from a cw light. Near-Fourier-transform-limit picosecond
pulses generated from the MZ-FCG were compressed into femtosecond order by pulse compression. Our system enables
flexible tuning of the repetition rate and pulse width, because those depend on the driving signal of the MZ-FCG. Pulse
trains of 200 fs width were continuously and stably generated without mode hopping, with a repetition rate range from 5
to 17 GHz. Our system consists of a modulator and compression fiber; thus, the configuration is simpler and more stable.
(C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 4 of 30
Author(s): Kwon, OH (Kwon, Oh-Hoon); Barwick, B (Barwick, Brett); Park, HS (Park, Hyun Soon); Baskin, JS
(Baskin, J. Spencer); Zewail, AH (Zewail, Ahmed H.)
Title: 4D visualization of embryonic, structural crystallization by single-pulse microscopy
Source: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF
AMERICA, 105 (25): 8519-8524 JUN 24 2008
Abstract:
In many physical and biological systems the transition from an amorphous to ordered native structure involves complex
energy landscapes, and understanding such transformations requires not only their thermodynamics but also the
structural dynamics during the process. Here, we extend our 4D visualization method with electron imaging to include
the study of irreversible processes with a single pulse in the same ultrafast electron microscope (UEM) as used before in
the single-electron mode for the study of reversible processes. With this augmentation, we report on the transformation
of amorphous to crystalline structure with silicon as an example. A single heating pulse was used to initiate
crystallization from the amorphous phase while a single packet of electrons imaged selectively in space the
transformation as the structure continuously changes with time. From the evolution of crystallinity in real time and the
changes in morphology, for nanosecond and femtosecond pulse heating, we describe two types of processes, one that
occurs at early time and involves a nondiffusive motion and another that takes place on a longer time scale. Similar
mechanisms of two distinct time scales may perhaps be important in biomolecular folding.
-------------------------------------------------------------------------------Record 5 of 30
Author(s): Geloni, G (Geloni, Gianluca); Saldin, E (Saldin, Evgeni); Schneidmiller, E (Schneidmiller, Evgeni); Yurkov,
M (Yurkov, Mikhail)
Title: A simple method for timing an XFEL source to high-power lasers
Source: OPTICS COMMUNICATIONS, 281 (14): 3762-3770 JUL 15 2008
Abstract:
We propose a technique for timing an X-ray free-electron laser (XFEL) to a high-power conventional laser with
femtosecond accuracy, yielding the relative jitter between pump and X-ray probe, and allowing sorting of experimental
results over a certain time window. The same electron bunch is used to produce both an XFEL pulse and an ultrashort
optical pulse by means of an optical radiator downstream of the X-ray undulator. Being produced by the same electron
bunch, these pulses are perfectly synchronized. Cross-correlation techniques will allow to determine relative jitter
between the optical pulse (and, thus, the XFEL pulse) and a pulse from an external pump-laser. Technical realization of
the proposed timing scheme uses an optical-replica synthesizer setup to be installed after the final bunch-compression
stage of the XFEL for electron bunch diagnostics purposes. A number of critical issues are quantitatively analyzed. (C)
2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 6 of 30
Author(s): Chi, H (Chi, Hao); Yao, JP (Yao, Jianping)
Title: Chirped RF pulse generation based on optical spectral shaping and wavelength-to-time mapping using a
nonlinearly chirped fiber Bragg grating
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1282-1287 MAY-JUN 2008
Abstract:
Chirped radio-frequency (RF) pulse generation based on optical spectral shaping and nonlinear wavelength-to-time
mapping in a nonlinearly chirped fiber Bragg grating (NLCFBG) is investigated. In the proposed approach, the
spectrum of a femtosecond pulse generated by a mode-locked fiber laser is shaped by an optical filter that has a
sinusoidal frequency response. The spectrum-shaped optical pulse is sent to the NLCFBG, to implement nonlinear
wavelength-to-time mapping. A chirped electrical pulse with the central frequency and chirp rate determined
respectively by the first- and second-order dispersions of the NLCFBG is then obtained at the output of a high-speed
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photodetector. An approximate model that describes the chirped RF pulse generation is derived, which is verified by
numerical simulations. Chirped pulse generation with a pulse compression ratio as high as 450 is demonstrated. The key
device in the chirped RF pulse generation system is the NLCFBG, which is investigated in detail with an emphasis on
the influence of its group delay ripples on the performance of the pulse generation system. Techniques to design and
fabricate the NLCFBG are also discussed. The proposed approach provides a potential solution for the generation. of
chirped RF pulse with a high central frequency and large chirp rate for applications in pulse compression radar systems.
-------------------------------------------------------------------------------Record 7 of 30
Author(s): Wang, C (Wang, Chao); Yao, JP (Yao, Jianping)
Title: Photonic generation of chirped microwave pulses using superimposed chirped fiber Bragg gratings
Source: IEEE PHOTONICS TECHNOLOGY LETTERS, 20 (9-12): 882-884 MAY-JUN 2008
Abstract:
A novel approach to generating linearly chirped microwave pulses in the optical domain based on spectral shaping and
linear frequency-to-time mapping is proposed and experimentally demonstrated. In the proposed system, the spectrum
of a femtosecond pulse generated by a mode-locked fiber laser is spectrum-shaped by an optical filter that consists of
two superimposed chirped fiber Bragg gratings (SI-CFBGs) with different chirp rates. The SI-CFBGs form a FabryPerot cavity with a cavity length linearly dependent on the resonance wavelength, thus a spectral response with an
increased or decreased free spectral range is generated. A chirped microwave pulse with the pulse shape identical to the
shaped spectrum is obtained at the output of a high-speed photodetector thanks to the frequency-to-time mapping in a
dispersive device. The proposed technique is experimentally demonstrated, a linearly chirped microwave pulse with a
central frequency of 15 GHz and a chirp rate of 0.0217 GHz/ps is experimentally generated.
-------------------------------------------------------------------------------Record 8 of 30
Author(s): Eom, TJ (Eom, Tae Joong); Sung, JH (Sung, Jae Hee); Kee, CS (Kee, Chul-Sik); Ko, DK (Ko, Do-Kyeong);
Lee, J (Lee, Jongmin); Choi, ES (Choi, Eun Seo)
Title: Wavelength-tunable broadband frequency-domain OCT source based on spatially filtered sub-10-fs pulsed laser
Source: IEEE PHOTONICS TECHNOLOGY LETTERS, 20 (9-12): 994-996 MAY-JUN 2008
Abstract:
A wavelength swept broadband source based on a sub-10-femtosecond (fs) pulse laser and a spatial filtering method was
developed for the application to frequency-domain optical coherence tomography (FD-OCT). The use of the sub-10-fs
laser with a galvano scanner operating at a high repetition rate provided a fast tunable broadband light source, which
tuned the spectral component across the spectral bandwidth of 1.10 nm at 1-kHz repetition rate. The spectrally filtered
light beam had 0.5-nm instantaneous spectral linewidths at 1-mW average output power. The implemented FD-OCT
system clearly imaged a narrow air gap between glass plates, with an axial resolution of 5 pm, which proved a potential
for the application of a short pulse laser source to the FD-OCT system. The proposed wavelength swept source scheme
can secure mode-hopping-free operation at fast tuning speed, which could be applicable for the FD-OCT system
properly.
-------------------------------------------------------------------------------Record 9 of 30
Author(s): Cerchez, M (Cerchez, M.); Jung, R (Jung, R.); Osterholz, J (Osterholz, J.); Toncian, T (Toncian, T.); Willi, O
(Willi, O.); Mulser, P (Mulser, P.); Ruhl, H (Ruhl, H.)
Title: Absorption of ultrashort laser pulses in strongly overdense targets - art. no. 245001
Source: PHYSICAL REVIEW LETTERS, 100 (24): 5001-5001 JUN 20 2008
Abstract:
Absorption measurements on solid conducting targets have been performed in s and p polarization with ultrashort, highcontrast Ti:sapphire laser pulses at intensities up to 5 x 10(16) W/cm(2) and pulse duration of 8 fs. The particular
relevance of the reported absorption measurements lies in the fact that the extremely short laser pulse interacts with
matter close to solid density during the entire pulse duration. A pronounced increase of absorption for p polarization at
increasing angles is observed reaching 77% for an incidence angle of 80 degrees. Simulations performed using a 2D
particle in cell code show a very good agreement with the experimental data for a plasma profile of L/lambda
approximate to 0.01.
-------------------------------------------------------------------------------Record 10 of 30
Author(s): Tsubouchi, M (Tsubouchi, Masaaki); Momose, T (Momose, Takamasa)
Title: Rovibrational wave-packet manipulation using shaped midinfrared femtosecond pulses toward quantum
computation: Optimization of pulse shape by a genetic algorithm - art. no. 052326
Source: PHYSICAL REVIEW A, 77 (5): 2326-2326 Part A MAY 2008
Abstract:
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We have numerically examined optimization of the experimentally achievable shapes of mid-infrared femtosecond laser
pulses to construct elementary quantum gates using molecular rovibrational states of a single molecule. Instead of
optimizing the electric field by optimal control theory, the method generally used in theoretical studies of coherent
control, the transmittance and the phase shift of conventional pulse shapers were optimized in the frequency domain by
a genetic algorithm. The target molecular system we examined was the rotation-vibration states of CO in the
X((1)Sigma(+)) ground electronic state. Although the existence of the rotational degrees of freedom makes the quantum
gate operation complicated, high fidelity of over 0.95 was achieved for one-rovibrational-qubit systems, which indicates
that a molecular quantum computer may be feasible for at least one-qubit calculations on a diatomic molecule. On the
other hand, two-qubit calculations are more difficult to achieve in a single CO molecule using rotational and vibrational
degrees of freedom as different qubits. The importance of the, control of the rotational in addition to the vibrational
wave packet in order to realize a molecular quantum computer is discussed.
-------------------------------------------------------------------------------Record 11 of 30
Author(s): Sim, HS (Sim, Hyung Sub); Lee, SH (Lee, Seong Hyuk)
Title: Numerical investigation of opto-energy phenomena in thin gold films irradiated by femtosecond pulse laser
considering quantum effects
Source: NUMERICAL HEAT TRANSFER PART A-APPLICATIONS, 54 (3): 279-292 2008
Abstract:
Nonequilibrium energy transport and optical characteristics in thin gold film structures irradiated by a femtosecond
pulse laser are examined numerically. With the use of a two-temperature model, the quantum effect is considered to
determine various thermo-optical properties such as electron heat capacity, electron thermal conductivity, collision
frequencies, reflectivity, and absorption rates. As a result, estimation on the electron temperature considering the
quantum effect is in better agreement with measurements than those without considering quantum effect. During a
femtoseond laser pulse, it is found that the electron and lattice are in nonequilibrium, the electron thermal conductivity
changes rapidly with time, and reflectivity decreases substantially because of the changes in dielectric function and
refractive index of gold films.
-------------------------------------------------------------------------------Record 12 of 30
Author(s): Schibli, TR (Schibli, T. R.); Hartl, I (Hartl, I.); Yost, DC (Yost, D. C.); Martin, MJ (Martin, M. J.);
Marcinkevicius, A (Marcinkevicius, A.); Fermann, ME (Fermann, M. E.); Ye, J (Ye, J.)
Title: Optical frequency comb with submillihertz linewidth and more than 10 W average power
Source: NATURE PHOTONICS, 2 (6): 355-359 JUN 2008
Abstract:
Growing demands for high average and peak powers in extreme nonlinear optics(1), attosecond-pulse(2,3) and extreme
ultraviolet comb generation experiments(4,5) can find a powerful solution in fibre-based mode-locked lasers. Using
passive enhancement cavities(6), fibre lasers have produced high-repetition-rate femtosecond pulse trains with
multikilowatt average powers and peak powers reaching hundreds of megawatts(7). One major challenge for novel highresolution spectroscopy and precision measurement in suboptical wavelength regions(8-10) is to transfer the state-ofthe-art optical phase coherence into the extreme ultraviolet domain through the extreme nonlinear optics enabled by
these high-power systems. We demonstrate here that optical frequency combs produced by high-power fibre lasers reach
unprecedented levels of performance in both precision and average power. We achieve a record low relative linewidth
of < 1 mHz between a traditional Ti:sapphire frequency comb and a novel 10 W average power fibre comb, at the same
time demonstrating all the necessary elements for power scaling precision comb technology to beyond 10 kW.
-------------------------------------------------------------------------------Record 13 of 30
Author(s): Bivona, S (Bivona, S.); Bonanno, G (Bonanno, G.); Burlon, R (Burlon, R.); Leone, C (Leone, C.)
Title: Radiation controlled energy of photoelectrons produced by two-color short pulses
Source: EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS, 160: 23-31 JUL 2008
Abstract:
We report on numerical results of energy spectra of photoelectrons emitted by irradiating a hydrogen atom with the
superposition of two pulses. The spectra have been obtained by numerical integration of the time dependent Schrodinger
equation. The highest frequency component of the pulse has been assumed to have low intensity and such a frequency
that a single photon may ionize the atom. Its duration has been assumed to lie in the range of subfemtoseconds. The
lowest frequency component that redistribute the energy of the ionized electrons has an higher intensity and duration of
few femtoseconds. We find that when the field are aligned, the electron energy spectra strongly depend on the time lag
of the fields, on the carrier-envelope relative phase of the lowest frequency pulse, and on the duration of the X-ray pulse.
Moreover it has been found that by changing the angle between the direction of the low and high frequency fields
significant modifications to the spectra occur that could be used to measure the relative orientation of the fields.
--------------------------------------------------------------------------------
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Record 14 of 30
Author(s): Kalashnikov, VL (Kalashnikov, V. L.)
Title: Femtosecond pulse enhancement in an external resonator: impact of dispersive and nonlinear effects
Source: APPLIED PHYSICS B-LASERS AND OPTICS, 92 (1): 19-23 JUL 2008
Abstract:
The effect of the high-order dispersions on a femtosecond pulse enhancement in an external resonator is analyzed. It is
shown that the degradation of the enhancement factor can be partially compensated by adjustment of group-delay,
dispersion and incident pulse width. Presence of a Kerr-medium inside an external resonator results in the stable quasisoliton formation that improves the enhancement factor. This provides the enhancement factor growth as well as its
robustness against the high-order dispersions, when the fourth-order dispersion is negative.
-------------------------------------------------------------------------------Record 15 of 30
Author(s): Morishige, N (Morishige, Naoyuki); Kesler-Diaz, A (Kesler-Diaz, Anna); Wahlert, AJ (Wahlert, Andrew J.);
Kurtz, RM (Kurtz, Ronald M.); Juhasz, T (Juhasz, Tibor); Sarayba, M (Sarayba, Melvin); Jester, JV (Jester, James V.)
Title: Corneal response to femtosecond laser photodisruption in the rabbit
Source: EXPERIMENTAL EYE RESEARCH, 86 (5): 835-843 MAY 2008
Abstract:
In this report we evaluated the effect of femtosecond laser energy on the development of corneal haze and keratocyte
activation in rabbits following intra-stromal photodisruption to create LASIK flaps using a modified commercial
femtosecond surgical laser. Three groups of flap parameters were studied: 1.5 mu J/pulse with 10 mu m spot separation
and complete side cut (Group 1); 3.5 mu J/pulse with 14 mu m spot separation and complete side cut (Group 2); 3.5 mu
J/pulse with 14 mu m spot separation and partial (50 mu m) side cut (Group 3). All flaps were left attached without
lifting to avoid epithelial contamination. Rabbits were then evaluated pre- and post-operatively by quantitative in vivo
and ex vivo confocal microscopy. The achieved flap thickness 1 week after surgery averaged 88.9 +/- 12.8, 90.8 +/- 6.9
and 86.5 +/- 6.8 mu m for Groups 1-3 respectively (p = NS). Interface thickness was significantly greater (p < 0.05) in
the higher energy groups averaging 40.0 +/- 11.2 and 37.7 +/- 5.7 mu m for Groups 2-3 compared to 28.6 +/- 4.5 mu m
for Group 1. Corneal haze was barely detectible and not significantly different between groups, although haze was
detected in the region of the side-cuts in Groups 1 and 2. No clinically significant changes in stromal or epithelial
thickness were noted. Laser confocal microscopy showed the presence of small diameter cells within the flap interface
that resided within disrupted regions of the corneal collagen lamellae. Keratocyte activation was only detected in
regions of the 100% side cut and not over the flap interface. In conclusion, the results of this study indicate that
photodisruption of the corneal stroma alone without flap elevation regardless of laser energy does not induce significant
corneal haze in the rabbit. However, a thicker stromal interface was seen with the higher energy suggesting greater
stromal damage. (c) 2008 Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 16 of 30
Author(s): Gelin, MF (Gelin, M. F.); Kosov, DS (Kosov, D. S.)
Title: Doorway-window description of sequential three-pulse photon echo signals
Source: CHEMICAL PHYSICS, 347 (1-3): 177-184 MAY 23 2008
Abstract:
The doorway-window (D W) approach is extended to the description of the three-pulse photon echo (3PPE) signals,
provided we can neglect the transient terms decaying as similar to E-i(T) (E-i(T) are the envelopes of the pulses
involved and T is the interpulse delay time during which the material system is in its electronic population state). A
simplified version of the DW approach is also developed, which is valid if we can additionally drop the transient terms
decaying as similar to E-i(tau), tau being the interpulse delay time during which the material system is in its electronic
coherent state. The proof-of-the-principle calculations of the 3PPE signal for the displaced harmonic oscillator model
demonstrate that the simplified DW approach performs well, sometimes even beyond its expected domain of validity. (c)
2007 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 17 of 30
Author(s): Yamaki, M (Yamaki, M.); Hoki, K (Hoki, K.); Kono, H (Kono, H.); Fujimura, Y (Fujimura, Y.)
Title: Quantum control of a chiral molecular motor driven by femtosecond laser pulses: Mechanisms of regular and
reverse rotations
Source: CHEMICAL PHYSICS, 347 (1-3): 272-278 MAY 23 2008
Abstract:
Rotational mechanisms of a chiral molecular motor driven by femtosecond laser pulses were investigated on the basis of
results of a quantum control simulation. A chiral molecule, (R)-2-methyl-cyclopenta-2,4-dienecarboaldehyde, was
treated as a molecular motor within a one-dimensional model. It was assumed that the motor is fixed on a surface and
driven in the low temperature limit. Electric fields of femtosecond laser pulses driving both regular rotation of the
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molecular motor with a plus angular momentum and reverse rotation with a minus one were designed by using a global
control method. The mechanism of the regular rotation is similar to that obtained by a conventional pump-dump pulse
method: the direction of rotation is the same as that of the initial wave packet propagation on the potential surface of the
first singlet (n pi*) excited state S-1. A new control mechanism has been proposed for the reverse rotation that cannot be
driven by a simple pump-dump pulse method. In this mechanism, a coherent Stokes pulse creates a wave packet
localized on the ground state potential surface in the right hand side. The wave packet has a negative angular momentum
to drive reverse rotation at an early time. (C) 2007 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 18 of 30
Author(s): Ma, YY (Ma, Yuan-yuan); Lu, X (Lu, Xin); Xi, TT (Xi, Ting-ting); Gong, QH (Gong, Qi-huang); Zhang, J
(Zhang, Jie)
Title: Widening of long-range femtosecond laser filaments in turbulent air
Source: OPTICS EXPRESS, 16 (12): 8332-8341 JUN 9 2008
Abstract:
The influence of air turbulence on the long- range filamentation of femtosecond laser pulses has been numerically
investigated. Simulations are performed for different parameters of air turbulence and laser pulses. Simulation results
indicate that the diameter of filaments formed by free propagated fs laser pulse can be widened to mm level under air
turbulence. However, the widening effect can be suppressed if the propagating distance before the on-set position of
filamentation becomes shorter. The reduction of non-linear focal length can be realized by pre-focusing of the laser
pulse or increasing of the laser intensity. The effect of the inner scale of air turbulence on the filamentation has also
been studied. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 19 of 30
Author(s): Smith, NI (Smith, N. I.); Kumamoto, Y (Kumamoto, Y.); Iwanaga, S (Iwanaga, S.); Ando, J (Ando, J.);
Fujita, K (Fujita, K.); Kawata, S (Kawata, S.)
Title: A femtosecond laser pacemaker for heart muscle cells
Source: OPTICS EXPRESS, 16 (12): 8604-8616 JUN 9 2008
Abstract:
The intracellular effects of focused near-infrared femtosecond laser irradiation are shown to cause contraction in
cultured neonatal rat cardiomyocytes. By periodic exposure to femtosecond laser pulse-trains, periodic contraction
cycles in cardiomyocytes could be triggered, depleted, and synchronized with the laser periodicity. This was observed in
isolated cells, and in small groups of cardiomyocytes with the laser acting as pacemaker for the entire group. A window
for this effect was found to occur between 15 and 30 mW average power for an 80 fs, 82 MHz pulse train of 780 nm,
using 8 ms exposures applied periodically at 1 to 2 Hz. At power levels below this power window, laser-induced
cardiomyocyte contraction was not observed, while above this power window, cells typically responded by a high
calcium elevation and contracted without subsequent relaxation. This laser-cell interaction allows the laser irradiation to
act as a pacemaker, and can be used to trigger contraction in dormant cells as well as synchronize or destabilize
contraction in spontaneously contracting cardiomyocytes. By increasing laser power above the window available for
laser-cell synchronization, we also demonstrate the use of cardiomyocytes as optically-triggered actuators. To our
knowledge, this is the first demonstration of remote optical control of cardiomyocytes without requiring exogenous
photosensitive compounds. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 20 of 30
Author(s): Schimpf, DN (Schimpf, Damian N.); Seise, E (Seise, Enrico); Limpert, J (Limpert, Jens); Tunnermann, A
(Tuennermann, Andreas)
Title: Decrease of pulse-contrast in nonlinear chirped-pulse amplification systems due to high-frequency spectral phase
ripples
Source: OPTICS EXPRESS, 16 (12): 8876-8886 JUN 9 2008
Abstract:
It is analytically shown that weak initial spectral phase modulations cause a pulse-contrast degradation at the output of
nonlinear chirped-pulse amplification systems. The Kerr-nonlinearity causes an energy-transfer from the main pulse to
side-pulses during nonlinear amplification. The relative intensities of these side-pulses can be described in terms of
Bessel-functions. It is shown that the intensities of the pulses are dependent on the magnitude of the accumulated
nonlinear phase-shift (i.e., the B-integral), the depth and period of the initial spectral phase-modulation and the slope of
the linear stretching chirp. The results are applicable to any type of laser amplifier that is based on the technique of
chirped-pulse amplification. The analytical results presented in this paper are of particular importance for high peakpower laser applications requiring high pulse-contrasts, e. g. high field physics. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 21 of 30
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Author(s): Rothhardt, J (Rothhardt, J.); Hadrich, S (Haedrich, S.); Roser, F (Roeser, F.); Limpert, J (Limpert, J.);
Tunnermann, A (Tuennermann, A.)
Title: 500 MW peak power degenerated optical parametric amplifier delivering 52 fs pulses at 97 kHz repetition rate
Source: OPTICS EXPRESS, 16 (12): 8981-8988 JUN 9 2008
Abstract:
We present a high peak power degenerated parametric amplifier operating at 1030 nm and 97 kHz repetition rate. Pulses
of a state-of-the art fiber chirped-pulse amplification (FCPA) system with 840 fs pulse duration and 410 mu J pulse
energy are used as pump and seed source for a two stage optical parametric amplifier. Additional spectral broadening of
the seed signal in a photonic crystal fiber creates enough bandwidth for ultrashort pulse generation. Subsequent
amplification of the broadband seed signal in two 1 mm BBO crystals results in 41 mu J output pulse energy.
Compression in a SF 11 prism compressor yields 37 mu J pulses as short as 52 fs. Thus, pulse shortening of more than
one order of magnitude is achieved. Further scaling in terms of average power and pulse energy seems possible and will
be discussed, since both concepts involved, the fiber laser and the parametric amplifier have the reputation to be
immune against thermo-optical effects. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 22 of 30
Author(s): Salzmann, W (Salzmann, W.); Mullins, T (Mullins, T.); Eng, J (Eng, J.); Albert, M (Albert, M.); Wester, R
(Wester, R.); Weidemueller, M (Weidemueller, M.); Merli, A (Merli, A.); Weber, SM (Weber, S. M.); Sauer, F (Sauer,
F.); Plewicki, M (Plewicki, M.); Weise, F (Weise, F.); Woeste, L (Woeste, L.); Lindinger, A (Lindinger, A.)
Title: Coherent transients in the femtosecond photoassociation of ultracold molecules - art. no. 233003
Source: PHYSICAL REVIEW LETTERS, 100 (23): 3003-3003 JUN 13 2008
Abstract:
We demonstrate the photoassociation of ultracold rubidium dimers using coherent femtosecond pulses. Starting from a
cloud of ultracold rubidium atoms, electronically excited rubidium molecules are formed with shaped photoassociation
pump pulses. The excited state molecules are projected with a time-delayed probe pulse onto molecular ion states which
are detected in a mass spectrometer. Coherent transient oscillations of the excited state population are observed in the
wings of the pump pulse, in agreement with the time-dependent solution of the Schrodinger equation of the excitation
process.
-------------------------------------------------------------------------------Record 23 of 30
Author(s): McDonald, JP (McDonald, Joel P.); Das, DK (Das, Dipak K.); Nees, JA (Nees, John A.); Pollock, TM
(Pollock, Tresa M.); Yallsove, SM (Yallsove, Steven M.)
Title: Approaching non-destructive surface chemical analysis of CMSX-4 superalloy with double-pulsed laser induced
breakdown spectroscopy
Source: SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY, 63 (5): 561-565 MAY 2008
Abstract:
Laser induced breakdown spectroscopy (LIBS) was performed on the CMSX-4 Ni-based superalloy using a
femtosecond pulsed laser. An orthogonal double-pulse technique was used to minimize surface damage associated with
LIBS. With this technique, the depth of ablation craters was reduced from 200 nm for single-pulse LIBS down to less
than 60 nm using orthogonal double-pulse LIBS. The technique also allowed the average velocity of the ablated
material to be determined, which ranged from 4720 +/- 560 m/s at a pump laser fluence of 3.1 J/cm(2) to 8150 +/- 1800
m/s at 10.1 J/cm(2) (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 24 of 30
Author(s): Deng, HX (Deng Haixiao); Wang, XT (Wang Xingtao); Dai, ZM (Dai Zhimin)
Title: Short-pulse length effects of the seed laser in high-gain harmonic generation free-electron laser - art. no. 040703
Source: PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS, 11 (4): 703-703 APR 2008
Abstract:
In order to generate coherent hard x-ray free-electron laser ( FEL), cascading stages of high-gain harmonic generation
( HGHG) scheme usually employ seed pulse with longitudinal length down to tens of femtoseconds. Such a short pulse
length ( SPL) seed laser, with broad bandwidth in the spectral domain, can no longer be characterized by
monochromatic light in FEL equations. In this paper, a set of self-consistent, multifrequency FEL equations is derived
to describe the interaction between the seed laser and the electrons in the modulator of HGHG. Moreover, the SPL
effects of the seed laser on the electron beam's energy modulation, the output pulse length, the output peak power, and
the output wavelength tuning in HGHG are theoretically and numerically investigated. Study demonstrates that the SPL
seed laser seriously and significantly influences the HGHG performances, and these influences have to be taken into
account in the design and optimization of the seeded FEL scheme.
-------------------------------------------------------------------------------Record 25 of 30
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Author(s): Maas, DJHC (Maas, D. J. H. C.); Rudin, B (Rudin, B.); Bellancourt, AR (Bellancourt, A. -R.); Iwaniuk, D
(Iwaniuk, D.); Marchese, SV (Marchese, S. V.); Sudmeyer, T (Suedmeyer, T.); Keller, U (Keller, U.)
Title: High precision optical characterization of semiconductor saturable absorber mirrors
Source: OPTICS EXPRESS, 16 (10): 7571-7579 MAY 12 2008
Abstract:
Semiconductor saturable absorber mirrors (SESAMs) have become a key element of many ultrafast laser sources,
enabling passively modelocked lasers with > 100 GHz repetition rate or with > 10 mu J pulse energy. Precise
knowledge of the nonlinear optical reflectivity is required to optimize the SESAMs for self-starting passive
modelocking at record high repetition rates or pulse energies. In this article, we discuss a new method for wide dynamic
range nonlinear reflectivity measurements. We achieve a higher accuracy (<0.05%) with a simpler and more costefficient measurement scheme compared with previous measurement systems. The method can easily be implemented
for arbitrary wavelength regions and fluence ranges. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 26 of 30
Author(s): Schlauch, T (Schlauch, T.); Li, M (Li, M.); Hofmann, MR (Hofmann, M. R.); Klehr, A (Klehr, A.); Erbert, G
(Erbert, G.); Trankle, G (Traenkle, G.)
Title: High peak power femtosecond pulses from modelocked semiconductor laser in external cavity
Source: ELECTRONICS LETTERS, 44 (11): 678-U30 MAY 22 2008
Abstract:
The generation of high peak power femtosecond pulses from an all semiconductor laser system is demonstrated. The
system is based on a passively modelocked two- section laser diode in an external cavity, a tapered amplifier and a
compact external pulse compressor. Pulse durations are achieved below 600 fs with an average optical power above 500
mW at a repetition rate of 330 MHz. This corresponds to a peak power of 2.5 kW, which is the highest value reported
for an all semiconductor ultrafast laser system so far.
-------------------------------------------------------------------------------Record 27 of 30
Author(s): Pestov, D (Pestov, Dmitry); Wang, X (Wang, Xi); Murawski, RK (Murawski, Robert K.); Ariunbold, GO
(Ariunbold, Gombojav O.); Sautenkov, VA (Sautenkov, Vladimir A.); Sokolov, AV (Sokolov, Alexei V.)
Title: Pulse shaping for mode-selective ultrafast coherent Raman spectroscopy of highly scattering solids
Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (5): 768-772 MAY
2008
Abstract:
We report on mode-selective ultrafast coherent anti-Stokes Raman spectroscopy (CARS) of a powder of sodium
dipicolinate. We produce a pair of stretched laser pulses with precisely adjusted matching chirp rates. We use the pulses
for frequency-resolved excitation of coherent molecular vibrations in this highly scattering medium. The induced
oscillations are probed with the third delayed ultrashort laser pulse. Since the attained spectral width of the pump-Stokes
excitation band is on the order of the spacing between the Raman lines, time-resolved CARS measurements reveal
single-mode as well as double-mode coherence decay dynamics, depending on the timing between the pump and Stokes
pulses. For a fixed probe pulse delay, the sweeping of the arrival time for one of the preparation pulses maps out the
CARS spectrum of the analyte. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 28 of 30
Author(s): Kukushkin, VA (Kukushkin, Vladimir A.)
Title: Generation of terahertz pulses from tightly focused single near-infrared pulses in double-plasmon waveguides
Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (5): 818-824 MAY
2008
Abstract:
The difference-frequency (DF) nonlinear mixing terahertz (THz) pulse generation from Fourier components of a single
tightly focused near-infrared pump pulse in a double-plasmon waveguide is considered. Under an appropriate choice of
its parameters, such a waveguide ensures an efficient transverse confinement of the THz field and provides low
dispersion of the THz mode refraction index. As a result, the generation of short powerful single-cycle THz pulses
becomes possible. In comparison with traditional (without waveguiding) schemes of DF THz pulse generation from a
single pump pulse (optical rectification), the proposed method allows one to significantly (by similar to 50 times) reduce
the pump pulse power while providing the same THz pulse output intensity and pump-THz conversion efficiency. (c)
2008 Optical Society of America.
-------------------------------------------------------------------------------Record 29 of 30
Author(s): Henis, Z (Henis, Z.); Milikh, G (Milikh, G.); Papadopoulos, K (Papadopoulos, K.); Zigler, A (Zigler, A.)
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Title: Generation of controlled radiation sources in the atmosphere using a dual femtosecond/nanosecond laser pulse art. no. 103111
Source: JOURNAL OF APPLIED PHYSICS, 103 (10): 3111-3111 MAY 15 2008
Abstract:
The generation of powerful radiation sources at predetermined remote locations in the atmosphere using dual
femtosecond/nanosecond laser pulses is proposed. The plasma channel generated in the wake of the collapsed beam
formed during intense ultrashort pulse propagation in the atmosphere serves as seed target plasma to absorb energy
delivered by a long pulse laser, inducing further ionization and significantly enhancing the energy density locally
deposited in the plasma. Energy equipartition on time scales shorter than 1 mu s results in large energy density in the
heated air and is followed by several orders of magnitude enhancement of the radiation emitted by the plasma channel.
The effect is demonstrated using a one-dimensional computational study. A proof-of-principle experiment is suggested.
(C) 2008 American Institute of Physics.
-------------------------------------------------------------------------------Record 30 of 30
Author(s): Wu, TC (Wu, T. C.); Shi, CH (Shi, C. H.); An, WK (An, W. K.); Zhang, X (Zhang, X.); Qiu, XJ (Qiu, X. J.)
Title: Muon motion induced by a superintense laser in muon-catalyzed fusion
Source: CONTRIBUTIONS TO PLASMA PHYSICS, 48 (4): 307-310 2008
Abstract:
Considering the mixture after muon-catalyzed fusion (mu CF) reaction as overdense plasma, we study muon motion in
the plasma produced by a superintense linearly polarized femtosecond laser pulse. Muon drift along the propagation of
laser radiation remains after the end of the laser pulse. At the peak laser intensity of 10(21) W/cm(2), muon goes from
the skin layer into field-free matter at short time which is much less than the pulse duration, before the laser pulse
reaches its maximum. Besides, the influence of the laser on other particles in the plasma is less. Hence, this work can
avoid muon sticking to alpha (alpha) effectively and reduce muon-loss probability in mu CF. (C) 2008 WILEY-VCH
Verlag GmbH & Co. KGaA, Weinheim.
High-Power Laser and Solid-State Laser
Record 1 of 18
Author(s): Kim, JW (Kim, J. W.); Jelger, P (Jelger, P.); Sahu, JK (Sahu, J. K.); Laurell, F (Laurell, F.); Clarkson, WA
(Clarkson, W. A.)
Title: High-power and wavelength-tunable operation of an Er,Yb fiber laser using a volume Bragg grating
Source: OPTICS LETTERS, 33 (11): 1204-1206 JUN 1 2008
Abstract:
Efficient high-power operation of double-clad Er,Yb-doped fiber lasers with fixed-wavelength and wavelength-tunable
resonator configurations using volume Bragg gratings for wavelength selection are reported. The fixed-wavelength laser
yielded a maximum output power of 103 W at 1552.6 nm with a linewidth of similar to 0.4 nm (FWHM) for a launched
pump power of 290 W at 976 nm. The wavelength-tunable laser could be tuned from 1528 to 1550 nm with a linewidth
of 0.2 nm (FWHM) and with output power in the range 30-38 W for a launched pump power of 120 W. The prospects
for further improvement in performance are considered. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 2 of 18
Author(s): Dascalu, C (Dascalu, C.)
Title: High-power TEM00 composite solid-state laser with a short, telescopic resonator
Source: JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS, 10 (6): 1530-1533 JUN 2008
Abstract:
A short, telescopic laser resonator design is proposed for high-power, single-transverse mode emission from a lens
shape composite solid-state laser. Such a laser combines the simplicity of the edge-pumped thin disk laser with the great
advantage of axial heat flow in a very thin, below 50 mu m, active media thickness. The efficiency, output power and
conditions of the single transverse mode oscillation are analyzed. For a device of a few millimeters wide, the slope
efficiency of 49% and the threshold of a few wafts are predicted. The possibility of output power of kW level is
analyzed.
-------------------------------------------------------------------------------Record 3 of 18
Author(s): Xiao, L (Xiao, Ling); Cheng, XJ (Cheng, Xiaojin); Xu, JQ (Xu, Jianqiu)
Title: High-power Nd : YAG planar waveguide laser with YAG and Al2O3 claddings
Source: OPTICS COMMUNICATIONS, 281 (14): 3781-3785 JUL 15 2008
Abstract:
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Thermal effects in Nd:YAG planar waveguide lasers with non-symmetrical claddings are discussed. The heat generated
in the active core can be removed more efficiently by directly contacting the active core to the heat sink. Several
cladding materials are compared to optimize the heat removal. Furthermore, uniform pumping is achieved with oblique
edge-pumping technique. Using quasi-CW pumping at 1 KHz repetition rate, an average output power of 280 W with a
slope efficiency of 38% is obtained with a positive unstable resonator. (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 4 of 18
Author(s): Li, SX (Li, Shao-Xia); Yu, G (Yu, Gang); Zheng, CY (Zheng, Cai-Yun); Liu, XB (Liu, Xiu-Bo)
Title: High-power laser beam shaping by inseparable two-dimensional binary-phase gratings for surface modification of
stamping dies
Source: OPTICS AND LASERS IN ENGINEERING, 46 (7): 508-513 JUL 2008
Abstract:
For surface modification of stamping dies, an inseparable two-dimensional binary-phase gratings is introduced to
implement the wavefront transformation of high-power laser beams. The design and fabrication of the gratings are
described in detail. Two-dimensional even sampling encoding scheme is adopted to overcome the limitations of
conventional Dammann grating in the design of two-dimensional output patterns. High diffractive efficiency (>70%)
can be achieved through the transformation of the Gaussian laser beam into several kinds of two-dimensional arrays in
focal plan. The application of the binary-phase gratings in the laser surface modification of ductile iron is investigated,
and the results show that the hardness and the wear resistance of the sample surface were improved significantly by
using the binary-phase gratings. (C) 2008 Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 5 of 18
Author(s): Yang, P (Yang, Ping); Liu, Y (Liu, Yuan); Ao, MW (Ao, Mingwu); Hu, SJ (Hu, Shijie); Xu, B (Xu, Bing)
Title: A wavefront sensor-less adaptive optical system for a solid-state laser
Source: OPTICS AND LASERS IN ENGINEERING, 46 (7): 517-521 JUL 2008
Abstract:
A wavefront sensor-less adaptive optical system has been set up. It consists of a deformable mirror, a high-voltage
amplifier, a set of solid-state laser system, a CCD camera, control software and a genetic algorithm. This adaptive
optical system does not employ a wavefront sensor to detect the wavefront information, but optimizes the light intensity
within a fixed aperture in the focal plane by a 19-element piezoelectricity deformable mirror. A genetic algorithm is
introduced to search the optimum surface profile of the deformable mirror for correcting the phase aberrations in a solidstate laser system. The far-field light intensity signal, which is measured by a CCD, is taken as the fitness function of
the genetic algorithm. In this paper, the performance and the efficiency of this wavefront sensor-less adaptive optical
system are presented. Both simulative results and experimental results are given and discussed. (C) 2008 Elsevier Ltd.
All rights reserved.
-------------------------------------------------------------------------------Record 6 of 18
Author(s): Belanger, E (Belanger, Erik); Bernier, M (Bernier, Martin); Faucher, D (Faucher, Dominic); Cote, D (Cote,
Daniel); Vallee, R (Vallee, Real)
Title: High-power and widely tunable all-fiber Raman laser
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1696-1701 MAY-JUN 2008
Abstract:
A high-power and widely tunable all-fiber Raman laser is demonstrated. The Raman fiber laser has been tuned over a
range of 60 nm from 1075 to 1135 nm and delivers up to 5.0 W of Stokes output power for 6.5 W of launched pump
power. Efficiencies ranging from 76.1 to 93.1% and laser thresholds from 0.78 to 2.59 W have been measured. The
spectrum of the depolarized Raman gain coefficient of the germanosilicate fiber has also been inferred from our
experimental measurements.
-------------------------------------------------------------------------------Record 7 of 18
Author(s): Xue, L (Xue, L.); Brueck, SRJ (Brueck, S. R. J.); Kaspi, R (Kaspi, R.)
Title: High-power continuous-wave single-longitudinal-mode operation of an optically pumped DFB laser at lambda
similar to 3.64 mu m
Source: IEEE PHOTONICS TECHNOLOGY LETTERS, 20 (9-12): 727-729 MAY-JUN 2008
Abstract:
High-power continuous-wave (CW) single-longitudinal-mode emission at 3.64 mu m is obtained from an optically
pumped distributed-feedback (DFB) laser. The Bragg stopband and two degenerate DFB modes are observed at certain
pump powers. The laser incorporates 14 InAs-InGaSb-InAs type-II quantum wells imbedded in an InGaAsSb
waveguide. The index-coupled 1-D grating is fabricated in the top clad using interference lithography and plasma
etching. A 110-mu m-wide stripe from a 1.9-mu m CW laser provides both optical pumping and gain guiding. Record
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high output power of more. than 560 mW per side is obtained at 80 K. The wavelength is tunable over a 6.8-nm range
by varying the pump power from 1 to 8.1 W.
-------------------------------------------------------------------------------Record 8 of 18
Author(s): Yang, XX (Yang, X. X.); Zhan, L (Zhan, L.); Shen, QS (Shen, Q. S.); Xia, YX (Xia, Y. X.)
Title: High-power single-longitudinal-mode fiber laser with a ring Fabry-Perot resonator and a saturable absorber
Source: IEEE PHOTONICS TECHNOLOGY LETTERS, 20 (9-12): 879-881 MAY-JUN 2008
Abstract:
We demonstrated a high-power single-longitudinal-mode (SLM) all-fiber laser. In the cavity, a fiber Bragg grating is
used to select the appropriate wavelength at 1565 nm, and a fiber ring is incorporated to act as a Fabry-Perot resonator,
which greatly reduces the longitudinal-mode density. Meanwhile, an un-pumped erbium-doped fiber serves as a
saturable absorber to ensure the SLM operation. Finally, a high-power SLM fiber laser producing as high as 867-mW
output power has been experimentally demonstrated.
-------------------------------------------------------------------------------Record 9 of 18
Author(s): Uetake, S (Uetake, S.); Yamaguchi, A (Yamaguchi, A.); Kato, S (Kato, S.); Takahashi, Y (Takahashi, Y.)
Title: High power narrow linewidth laser at 556 nm for magneto-optical trapping of ytterbium
Source: APPLIED PHYSICS B-LASERS AND OPTICS, 92 (1): 33-35 JUL 2008
Abstract:
We present a high-power and narrow-linewidth laser for intercombination magneto-optical trapping of ytterbium (Yb)
atoms using the 6s(2) S-1(0)-6s6p P-3(1) transition. The system generates 415 mW of continuous wave laser radiation at
556 nm with a linewidth of less than 100 kHz. It is based on a commercial 1W fiber laser with a frequency doubling
stage. Up to 58% frequency doubling efficiency is obtained at an input power of 0.5W by using a lithium triborate
crystal as a nonlinear medium. The system has been successfully used for laser cooling of Yb atoms.
-------------------------------------------------------------------------------Record 10 of 18
Author(s): Jeong, TM (Jeong, Tae Moon); Ko, DK (Ko, Do-Kyeong); Lee, JM (Lee, Jongmin)
Title: Deformation of the focal spot of an ultrashort high-power laser pulse due to chromatic aberration by a beam
expander
Source: JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 52 (6): 1767-1773 JUN 2008
Abstract:
The spatial and temporal intensity distribution of a focal spot is investigated when an ultrashort high-power laser pulse
is focused with chromatic aberration induced by a simple beam expander. The chromatic aberration due to the simple
beam expander is calculated and measured for the 100-TW Ti:sapphire laser system at the Advanced Photonics
Research Institute. The chromatic aberration reduces the peak intensity of the focal spot and broadens the temporal
profile of the focal spot. By calculating the spatial and temporal intensity distribution of the focal spot, we can
accurately estimate the peak intensity of the focal spot for the ultrashort high-power laser pulse with chromatic
aberration. To avoid chromatic aberration, an air-spaced achromatic beam expander is designed and characterized for
application to the ultrashort high-power laser system.
-------------------------------------------------------------------------------Record 11 of 18
Author(s): Oliva, E (Oliva, E.); Dimroth, F (Dimroth, F.); Bett, AW (Bett, A. W.)
Title: GaAs converters for high power densities of laser illumination
Source: PROGRESS IN PHOTOVOLTAICS, 16 (4): 289-295 JUN 2008
Abstract:
Photovoltaic power converters can be used to generate electricity directly from laser light. In this paper we report the
development of GaAs PV power converters with improved conversion efficiency at high power densities. The
incorporation of a lateral conduction layer (LCL) on top of the window layer resulted in a considerable gain in
efficiency at high illumination levels. Additional performance improvements were obtained by using a metal electrode
grid design and antireflection coating optimised for monochromatic and inhomogeneous laser light. Maximum
monochromatic (810 nm) optical-to-electrical conversion efficiency of 54.9% at 36.5 W/cm(2) has been achieved. The
characteristics of laser power converters with p/n and n/p polarity are discussed in this paper. Moreover, different
materials and doping levels were applied in the LCL. The performance of these different device structures at high laser
intensity is presented and discussed. It is shown that the lateral series resistance of the cell has a major impact on the
overall device performance. Copyright (C) 2008 John Wiley & Sons, Ltd.
-------------------------------------------------------------------------------Record 12 of 18
Author(s): Khalilzadeh, J (Khalilzadeh, Javad); Ghorbanzadeh, AM (Ghorbanzadeh, A. M.); Moghimi, A (Moghimi,
Abolghasem)
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Title: Influence of dyes doped in solid state polymeric matrices as spectral converters on efficiency of a flash-lamp
pumped Nd : YAG laser
Source: OPTICAL MATERIALS, 30 (10): 1527-1530 JUN 2008
Abstract:
Organic dye materials doped in poly-methyl methacrylate matrix were used as spectral converters to increase the energy
efficiency of a flash-lamp pumped Nd:YAG laser. In this process, the useless part of emitted spectrum from the
pumping lamp is absorbed by dye molecules and, subsequently, re-emitted at longer wavelengths where the narrow
absorption line of neodymium ion at about 580 nm can be used more efficiently. As a result, approximately 40%
enhancement in energy efficiency was achieved. (c) 2007 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 13 of 18
Author(s): Zhou, R (Zhou, Rui); Ruan, SC (Ruan, Shuangchen); Du, CL (Du, Chenlin); Yao, JQ (Yao, Jianquan)
Title: 26.3-W continuous-wave, diode-double-end-pumped all-solid-state Nd : GdVO4 laser operating at 1.34 mu m
Source: OPTICS COMMUNICATIONS, 281 (13): 3510-3513 JUL 1 2008
Abstract:
A high-power continuous-wave (CW) all-solid-state Nd:GdVO4 laser operating at 1.34 mu m is reported here. The laser
consists of a low doped level Nd:GdVO4 crystal double-end-pumped by two high-power fiber-coupled diode lasers and
a simple plane-parallel cavity. At an incident pump power of 88.8 W, a maximum CW output of 26.3 W at 1.34 mu m is
obtained with a slope efficiency of 33.7%. To the best of our knowledge, this is the highest output at 1.34 mu m ever
generated by diode-end-pumped all-solid-state lasers. (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 14 of 18
Author(s): Viejo, F (Viejo, F.); Pardo, A (Pardo, A.); Rams, J (Rams, J.); Merino, MC (Merino, M. C.); Coy, AE (Coy,
A. E.); Arrabal, R (Arrabal, R.); Matykina, E (Matykina, E.)
Title: High power diode laser treatments for improving corrosion resistance of A380/SiCp aluminium composites
Source: SURFACE & COATINGS TECHNOLOGY, 202 (17): 4291-4301 MAY 25 2008
Abstract:
Laser surface melting (LSM), using a high power diode laser, was used to modify the electrochemical behaviour of
A380/SiC/xxp aluminium composites in aerated 3.5 wt.% NaCl solution. Corrosion mechanism was determined by
potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM),
scanning Kelvin probe force microscopy (SKPFM) and low-angle X-ray diffraction (XRD). Laser-treated surface
revealed a refined microstructure with homogeneous microdendrites, good matrix/reinforcement bonding and absence of
cathodic intermetallic compounds. As a result, laser treatment increased the surface hardness and reduced localised
corrosion attack. (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 15 of 18
Author(s): Nakagawa, T (Nakagawa, Tomoya); Maeda, N (Maeda, Naoyuki); Cekic, O (Cekic, Osman); Fujikado, T
(Fujikado, Takashi); Tano, Y (Tano, Yasuo); Murakami, A (Murakami, Atsutoshi); Yoshimura, M (Yoshimura,
Masashi); Mori, Y (Mori, Yusuke); Sasaki, T (Sasaki, Takamoto); Kitano, H (Kitano, Hiroshi); Owa, S (Owa, Soichi)
Title: Corneal ablation with new 193 nm solid-state laser - Preliminary experiments
Source: JOURNAL OF CATARACT AND REFRACTIVE SURGERY, 34 (6): 1019-1023 JUN 2008
Abstract:
PURPOSE: To assess the ability of a newly developed 193 nm solid-state laser to ablate the cornea.
SETTING: Osaka University, Osaka, Japan.
METHODS: A prototype laser engine was developed by combining a 1547 nm laser diode, fiber amplifiers, and 5
stages of a frequency-conversion system using CsLiB6O10 crystals as the last stage. Poly(methyl methacrylate)
(PMMA) plates were exposed to the prototype laser beam to determine the relationship between the fluence and ablation
rate, Laser irradiation of porcine corneas was performed to induce morphological changes, and the quality of the lesions
was determined by light and scanning electron microscopy.
RESULTS: The relationship between the fluence and ablation rate of the 193 nm solid-state laser was comparable to
that of the argon-fluoride excimer laser. Light and scanning electron microscopy of the porcine corneas showed that the
linear and square lesions had sharp, clean edges.
CONCLUSIONS: Smooth ablations of PMMA plates and porcine corneas were obtained by the laser. Further
investigations must be conducted to determine whether this laser can be an alternative laser source for keratorefractive
surgery.
-------------------------------------------------------------------------------Record 16 of 18
Author(s): Liu, HJ (Liu, Hongjun); Gao, CX (Gao, Cunxiao); Tao, JT (Tao, Jintao); Zhao, W (Zhao, Wei); Wang, YS
(Wang, Yishan)
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Title: Compact tunable high power picosecond source based on Yb-doped fiber amplification of gain switch laser diode
Source: OPTICS EXPRESS, 16 (11): 7888-7893 MAY 26 2008
Abstract:
A compact tunable high power picosecond source based on Yb-doped fiber amplification of gain switch laser diode is
demonstrated. A multi-stage single mode Yb-doped fiber preamplifier was combined with a single mode double-clad
Yb-doped fiber main amplifier to construct the amplification system, which is seeded by a gain switch laser diode. By
optimizing preamplifier's parameters to compensate the seed spectrum gain, a "flat top" broadband spectrum is obtained
to realize wavelength tunable output with a self-made tunable filter. The tunable pulses were further amplified to 3.5 W
average power 90 ps pulses at 1 MHz repetition rate, and the center wavelength was tunable in the ranges from 1053 nm
to 1073 nm with excellent beam quality. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 17 of 18
Author(s): Huang, PH (Huang, Pei-Hsing); Lai, HY (Lai, Hsin-Yi)
Title: Pressure-induced solid-state lattice mending of nanopores by pulse laser annealing - art. no. 255701
Source: NANOTECHNOLOGY, 19 (25): 55701-55701 JUN 25 2008
Abstract:
This paper presents the pressure-induced solid-state lattice mending of nanopores in single-crystal copper by
femtosecond laser annealing processes. The microscopic mechanism of lattice mending is investigated by a modified
continuum-atomistic modeling approach. Three typical lattice mending phases, including (i) the incubation of
dislocation nucleation, (ii) plastic deformation under the combined effect of pressure and atomic thermal diffusion, and
(iii) lattice recovery and reconstruction, are characterized via the microscopic structure changes and transient
thermodynamic trajectories. The simulation results reveal that the structural mending of a pore is originated in
heterogeneous nucleation of dislocations from the pore surface. The shear-induced multiple lattice glides are found to
significantly contribute to the mending of a nanopore in the process of solid-state structural mending. The mending rates
of two different modes, the pressure-induced and the classical unsteady-state atomic diffusion, are estimated and found
to be very different from each other, by an order of 10(4). In addition, the location of the pore is also found to
significantly influence the annealing threshold. Since the largest amplitude of the pressure wave is built up at a
characteristic depth of approximately 45 nm below the irradiated surface, the shock wave will directly impinge on the
pore and induce a fast solid-state lattice mending if the pore is located within the lower limit of the range of the
characteristic depth. Furthermore, it is also interesting to note that the mending of a nanopore close to the characteristic
depth by annealing fluence is generally lower than that of a pore near the surface. These results provide vital insights of
photomechanical interactions with the microstructure of metallic solid, and the proposed approach can be further
considered and enhanced to predict the mending depth for various defects in the future.
-------------------------------------------------------------------------------Record 18 of 18
Author(s): Sabaeian, M (Sabaeian, Mohammad); Nadgaran, H (Nadgaran, Hamid); Mousave, L (Mousave, Laleh)
Title: Analytical solution of the heat equation in a longitudinally pumped cubic solid-state laser
Source: APPLIED OPTICS, 47 (13): 2317-2325 MAY 1 2008
Abstract:
Knowledge about the temperature distribution inside solid-state laser crystals is essential for calculation of thermal
phase shift, thermal lensing, thermally induced birefringence, and heat-induced crystal bending. Solutions for the
temperature distribution for the case of steady-state heat loading have appeared in the literature only for simple
cylindrical crystal shapes and are usually based on numerical techniques. For the first time, to our knowledge, a full
analytical solution of the heat equation for an anisotropic cubic cross-section solid-state crystal is presented. The crystal
is assumed to be longitudinally pumped by a Gaussian pump profile. The pump power attenuation along the crystal and
the real cooling mechanisms, such as convection, are considered in detail. A comparison between our analytical
solutions and its numerical counterparts shows excellent agreement when just a few terms are employed in the series
solutions. (C) 2008 Optical Society of America.
Laser Application
Record 1 of 9
Author(s): Xu, Y (Xu, Yu); Shen, MR (Shen, Mingrong)
Title: Fabrication of anatase-type TiO2 films by reactive pulsed laser deposition for photocatalyst application
Source: JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, 202 (1-3): 301-306 JUN 20 2008
Abstract:
TiO2 films having anatase crystal structure were prepared on glass substrates by reactive pulsed laser deposition using a
metallic Ti target in an O-2 gas ambient. At a fixed substrate temperature of 400 degrees C, the crystalline structure,
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surface morphology, optical properties and photocatalytic activity of the TiO2 films were greatly affected by the O-2
gas pressure. It was found that nearly pure anatase-phase TiO2 film can be obtained under an O-2 pressure of 15 Pa,
which bad smallest grain size among the films deposited under various O-2 gas pressure from 5 to 30 Pa. This film also
showed good optical transmittance between the wavelength of 200 and 800 nm and high photocatalytic efficiency on the
decomposition of methylene blue in aqueous solution. Discussions were given to explain the experimental phenomena.
(C) 2007 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 2 of 9
Author(s): Park, I (Park, I.); Sydlo, C (Sydlo, C.); Fischer, I (Fischer, I.); Elsasser, W (Elsaesser, W.); Hartnagel, HL
(Hartnagel, H. L.)
Title: Generation and spectroscopic application of tunable continuous-wave terahertz radiation using a dual-mode
semiconductor laser - art. no. 065305
Source: MEASUREMENT SCIENCE & TECHNOLOGY, 19 (6): 65305-65305 JUN 2008
Abstract:
We present a tunable continuous-wave terahertz radiation source based on photomixing of a tunable dual-mode
semiconductor laser on a log-periodic antenna. The discontinuously tunable dual-mode emission of the laser is achieved
by spectrally filtered feedback in a double-external-cavity configuration. Two different two-frequency lasing regimes
have been identified: pure dual-mode and dual-mode-comb emission. We spectrally investigate the laser emission in
these two regimes and study the consequences for the generation of terahertz radiation. Under pure dual-mode emission,
we achieve higher power, higher coherence and good tunability of the THz radiation. We demonstrate by detecting
absorption lines of water vapor and hydrochloric acid gas that our concept for a tunable continuous-wave terahertz
radiation source offers attractive properties for spectroscopic applications.
-------------------------------------------------------------------------------Record 3 of 9
Author(s): Mateo, E (Mateo, Ester); Lahoz, R (Lahoz, Ruth); de la Fuente, GF (de la Fuente, German F.); Paniagua, A
(Paniagua, Andres); Coronas, J (Coronas, Joaquin); Santamaria, J (Santamaria, Jesus)
Title: Preparation and application of silicalite-1 micromembranes on laser-perforated stainless steel sheets
Source: JOURNAL OF MEMBRANE SCIENCE, 316 (1-2): 28-34 MAY 15 2008
Abstract:
Silicalite-1 micromembranes of approximately 80 mu m in diameter have been prepared by synthesizing the zeolite
material inside a network of perforations created by using a Nd-YAG laser on 75 mu m thick stainless steel sheets.
Several strategies have been introduced here to reduce the thickness of the micromembranes synthesized; among these
the most successful involved using a polyamide filling to reduce the volume of the microperforations accessible to the
synthesis solution. The density of microperforations could be tailored to prepare arrays of micromembranes of different
overall porosity (1.8, 3.7, 6.6 and 7.7%). The micromembranes performed well in the propane/N-2 separation, showing
a maximum propane/N2 separation factor of 46, at a propane permeance of about 5 x 10(-6) mol/(m(2) s Pa). (C) 2007
Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 4 of 9
Author(s): Zoriy, MV (Zoriy, Myroslav V.); Kayser, M (Kayser, Markus); Becker, JS (Becker, J. Sabine)
Title: Possibility of nano-local element analysis by near-field laser ablation inductively coupled plasma mass
spectrometry (LA-ICP-MS): New experimental arrangement and first application
Source: INTERNATIONAL JOURNAL OF MASS SPECTROMETRY, 273 (3): 151-155 JUN 15 2008
Abstract:
A near-field laser ablation inductively coupled plasma mass spectrometric (NF-LA-ICP-MS) procedure was created for
element analysis in the nm resolution range. The method utilizes a well-known near-field effect in order to enhance the
incident light energy on the thin tip of a Ag needle during the laser ablation process. A robust needle etching procedure
was developed to produce the thin needles with a tip diameter in the range of hundreds of nm. An experimental
arrangement was constructed to control the "sample-to-tip" distance via the measurements of tunnel current between the
needle and sample surface. The NF-LA-ICP-MS technique thus developed was applied to analyze thin Au films
deposited onto a Si substrate. The observed craters ranged from 500 nm to about 1 mu m in diameter and were
dependent on the needle used as well as on the "sample-to-tip" distance. These results were also confirmed by mass
spectrometric measurements of the Au sample. Theoretical calculations performed showed that using the developed NFLA-ICP-MS arrangement a detection efficiency of 2.7 x 10(-5) cps per ablated Au atom can be achieved. (C) 2008
Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 5 of 9
Author(s): Didierjean, J (Didierjean, Julien); Herault, E (Herault, Emilie); Balembois, F (Balembois, Francois); Georges,
P (Georges, Patrick)
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Title: Thermal conductivity measurements of laser crystals by infrared thermography. Application to Nd: doped crystals
Source: OPTICS EXPRESS, 16 (12): 8995-9010 JUN 9 2008
Abstract:
We present a thermal conductivity measurement method for laser crystals based on thermal mapping of the crystal face
by an infrared camera. Those measurements are performed under end-pumping of the laser crystal and during laser
operation. The calculation of the fraction of pump power converted into heat is therefore simplified, and it is possible to
link easily the temperature in the crystal to the thermal conductivity. We demonstrate the efficiency of this measurement
method with a Nd:YAG crystal, before using it to compare Nd:YVO4 and Nd:GdVO4 crystals. (c) 2008 Optical Society
of America.
-------------------------------------------------------------------------------Record 6 of 9
Author(s): Lu, JB (Lu, Jiabao); Yu, KH (Yu, Kehan); Wang, HY (Wang, Hongyu); He, JF (He, Junfang); Cheng, GH
(Cheng, Guanghua); Qin, CY (Qin, Chunyang); Lin, JM (Lin, Jianming); Wei, W (Wei, Wei); Peng, B (Peng, Bo)
Title: Optical properties of Nd(TTA)(3)(TPPO)(2) doped polymer and its potential laser application
Source: OPTICAL MATERIALS, 30 (10): 1531-1537 JUN 2008
Abstract:
In this work, the Nd(III) complex doped PMMA with high stimulated emission cross-section, which is one of the most
important parameters for laser design, was presented. The molecular structure of the complex, Nd(TTA)(3)(TPPO)(2)
(HTTA: 2-thenoyltrifluoroacetone, TPPO: triphenylphosphine oxide), was characterized by single-crystal X-ray
diffraction. From the absorption and luminescence spectra, the Judd-Ofelt parameters (Omega(2), Omega(4) and 26) of
the Nd3+ ion in PMMA were obtained and the radiative properties were discussed using Judd-Ofelt theory. The
stimulated emission cross-section of the emission band at 1.060 mu m is 2.75 x 10(-20) cm(2), which is higher than that
of other Nd(III) complex doped organic systems and even comparable with some laser glasses. On the basis of the
experimental data and Judd-Ofelt analysis, the F-4(3/2) -> I-4(11/2) transition of the Nd3+ ion in PMMA can be
considered as a possible laser transition. (c) 2007 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 7 of 9
Author(s): Kondo, HV (Kondo, Hiro-Vuki); Hamada, N (Hamada, Naoya)
Title: Application of laser ablation-laser induced fluorescence spectroscopy to analysis of steel - Detection of low
carbon in steel
Source: TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN, 94 (5): 155-159
2008
Abstract:
Fluorescence of atomic carbon in steel was detected at 193.09 nm by the excitation with laser pulse tuned at 247.85 nm.
Solid steel samples were irradiated by pulsed Nd:YAG laser (ablation laser) to generate atomic vapor, which was then
illuminated by the probe laser. One of ionic iron lines is very close to the excitation line for carbon. However, its
interaction was not found to be very significant because population of ionic iron decreased faster than that of atomic
carbon in a transient plasma induced by the ablation laser. When the probe laser was coaxial with the ablation laser,
fluorescence spectra with high selectivity was observed with delay of 50 mu s between two lasers. Fluorescence
intensities were in a good linear correlation with contents of carbon in steel samples in a range of 83-5000 mu g/g,
which suggested that quantitative detection of carbon would be possible with the developed method.
-------------------------------------------------------------------------------Record 8 of 9
Author(s): Ramil, A (Ramil, A.); Lopez, AJ (Lopez, A. J.); Yanez, A (Yanez, A.)
Title: Application of artificial neural networks for the rapid classification of archaeological ceramics by means of laser
induced breakdown spectroscopy (LIBS)
Source: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 92 (1): 197-202 JUL 2008
Abstract:
The aim of this work is to analyze the feasibility of artificial neural networks (ANN) for the classification, in function of
the provenance, of archaeological ceramics Terra Sigillata analyzed by means of laser-induced breakdown spectroscopy
(LIBS). In order to automate and facilitate the task of comparison of LIBS spectra, two ANN algorithms are proposed:
One is fed with the whole LIBS spectra and the other with the areas of the most intense peaks of the spectra. In both
cases, an analysis of the network architecture as a function of the number of hidden neurons and number of epochs of
training was carried out in order to optimize the performance of the network. Following both procedures, the correct
classification (higher than the 95% of success) of Terra Sigillata pieces from their LIBS spectra can be achieved in a
systematic and objective way.
-------------------------------------------------------------------------------Record 9 of 9
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Author(s): Boulon, G (Boulon, G.); Guyot, Y (Guyot, Y.); Canibano, H (Canibano, H.); Hraiech, S (Hraiech, S.);
Yoshikawa, A (Yoshikawa, A.)
Title: Characterization and comparison of Yb3+-doped YA1O(3) perovskite crystals (Yb : YAP) with Yb3+-doped
Y3Al5O12 garnet crystals (Yb : YAG) for laser application
Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (5): 884-896 MAY
2008
Abstract:
High-optical-quality single crystals of Yb3+-doped YAlO3 perovskite (Yb3+: YAP) were grown by the Czochralski
(CZ) method and characterized. From polarized absorption and emission spectra, assignment of the Yb3+ energy levels
was proposed. Yb3+ concentration dependence of experimental decay times allows us to study concentration quenching
and suggests both strong radiative and nonradiative energy transfers, from Yb3+ ions to impurities, well described by a
limited diffusion model. Yb3+: YAP crystal is a potentially useful polarized laser gain medium in laser-diode-pumped
solid-state configurations. 5.7 at. % Yb3+ optimum concentration was deduced by prediction of laser performances. In
addition, thermal properties and figure of merit, which is defined from our own model taking into account only
spectroscopic data, were also compared with those of Yb3+-doped YAG. (c) 2008 Optical Society of America.
Nonlinear Optics
Record 1 of 15
Author(s): Stolen, RH (Stolen, Roger H.)
Title: The early years of fiber nonlinear optics
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1021-1031 MAY-JUN 2008
Abstract:
This paper looks back at the beginnings of nonlinear optics in fibers and some of the subsequent work that forms the
basic underpinnings of the modern field. There is a brief look at some of the major applications and current trends.
-------------------------------------------------------------------------------Record 2 of 15
Author(s): Portolan, S (Portolan, S.); Di Stefano, O (Di Stefano, O.); Savasta, S (Savasta, S.); Rossi, F (Rossi, F.);
Girlanda, R (Girlanda, R.)
Title: Dynamics-controlled truncation scheme for quantum optics and nonlinear dynamics in semiconductor
microcavities - art. no. 195305
Source: PHYSICAL REVIEW B, 77 (19): 5305-5305 MAY 2008
Abstract:
We present a systematic theory of Coulomb-induced correlation effects in the nonlinear optical processes within the
strong-coupling regime. In this paper, we shall set a dynamics controlled truncation scheme microscopic treatment of
nonlinear parametric processes in semiconductor microcavities including the electromagnetic field quantization. It
represents the starting point for the microscopic approach to quantum optics experiments in the strong-coupling regime
without any assumption on the quantum statistics of electronic excitations (excitons) involved. We exploit a previous
technique, which was used in the semiclassical context, which, once applied to four-wave mixing in quantum wells,
allowed us to understand a wide range of observed phenomena. We end up with dynamical equations for exciton and
photon operators, which extend the usual semiclassical description of Coulomb interaction effects in terms of a meanfield term plus a genuine noninstantaneous four-particle correlation to quantum optical effects.
-------------------------------------------------------------------------------Record 3 of 15
Author(s): Conti, C (Conti, C.); Fratalocchi, A (Fratalocchi, A.); Ruocco, G (Ruocco, G.); Sette, F (Sette, F.)
Title: Nonlinear optics in the X-ray regime: nonlinear waves and self-action effects
Source: OPTICS EXPRESS, 16 (12): 8324-8331 JUN 9 2008
Abstract:
We study the nonlinear refraction of X-rays in highly ionized condensed matter by using a classical model of a cold
electron plasma in a lattice of still ions coupled with Maxwell equations. We discuss the existence and stability of
nonlinear waves. As a real-world example, we consider beam self-defocusing in crystalline materials (B, C, Li, Na). We
predict that nonlinear processes become comparable to the linear ones for focused beams with powers of the order of
mc(3)/r(o) (approximate to 10 GW), the classical electron power. As a consequence, nonlinear phenomena are expected
in currently exploited X-ray Free-Electron Lasers and in their future developments. (C) 2008 Optical Society of
America.
-------------------------------------------------------------------------------Record 4 of 15
Author(s): Hayat, A (Hayat, Alex); Elor, Y (Elor, Yotam); Small, E (Small, Eran); Orenstein, M (Orenstein, Meir)
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Title: Phasematching in semiconductor nonlinear optics by linear long-period gratings - art. no. 181110
Source: APPLIED PHYSICS LETTERS, 92 (18): 81110-81110 MAY 5 2008
Abstract:
We experimentally demonstrate a phasematching technique for frequency conversion in nonlinear semiconductor
structures by employing linear long-period gratings. We designed a specific semiconductor photonic device for second
harmonic generation using coupled-mode equations with parameters extracted from beam propagation method
simulations. Optical frequency converters were fabricated according to the design with the main feature; linear longperiod weak gratings imprinted on semiconductor waveguides, providing the required photon momentum difference for
matching the phases of the different-wavelength photons. The measured nonlinear conversion efficiency and its
spectrum comply with our theoretical predictions. (C) 2008 American Institute of Physics.
-------------------------------------------------------------------------------Record 5 of 15
Author(s): Goulielmakis, E (Goulielmakis, E.); Schultze, M (Schultze, M.); Hofstetter, M (Hofstetter, M.); Yakovlev,
VS (Yakovlev, V. S.); Gagnon, J (Gagnon, J.); Uiberacker, M (Uiberacker, M.); Aquila, AL (Aquila, A. L.); Gullikson,
EM (Gullikson, E. M.); Attwood, DT (Attwood, D. T.); Kienberger, R (Kienberger, R.); Krausz, F (Krausz, F.);
Kleineberg, U (Kleineberg, U.)
Title: Single-cycle nonlinear optics
Source: SCIENCE, 320 (5883): 1614-1617 JUN 20 2008
Abstract:
Nonlinear optics plays a central role in the advancement of optical science and laser- based technologies. We report on
the confinement of the nonlinear interaction of light with matter to a single wave cycle and demonstrate its utility for
time- resolved and strong- field science. The electric field of 3.3- femtosecond, 0.72- micron laser pulses with a
controlled and measured waveform ionizes atoms near the crests of the central wave cycle, with ionization being
virtually switched off outside this interval. Isolated sub- 100- attosecond pulses of extreme ultraviolet light ( photon
energy similar to 80 electron volts), containing similar to 0.5 nanojoule of energy, emerge from the interaction with a
conversion efficiency of similar to 10(-6). These tools enable the study of the precision control of electron motion with
light fields and electron- electron interactions with a resolution approaching the atomic unit of time (similar to 24
attoseconds).
-------------------------------------------------------------------------------Record 6 of 15
Author(s): Baehr-Jones, TW (Baehr-Jones, Tom W.); Hochberg, MJ (Hochberg, Michael J.)
Title: Polymer silicon hybrid systems: A platform for practical nonlinear optics
Source: JOURNAL OF PHYSICAL CHEMISTRY C, 112 (21): 8085-8090 MAY 29 2008
Abstract:
Nonlinear optical polymers can provide a unique and powerful platform for building a number of useful optical devices.
Traditionally, they have been used in all-polymer waveguiding systems, which have had a number of severe practical
limitations. Silicon has recently become a popular material for integrated optical systems, but it lacks strong nonlinear
properties. By combining nonlinear optical polymer claddings and silicon waveguides in a hybrid system, we show that
a number of significant advantages are obtained. In particular, fabrication can be done using conventional CMOS
processing, with the polymer added as part of back-end processes (after all of the high-temperature processing is
completed), and the waveguide structure can also serve as an ultracompact set of electrodes. We discuss some optical
devices that have recently been built into this system, which already show superior performance to anything achieved in
silicon or polymer alone. We also propose using second-order nonlinear polymers with silicon for parametric
amplification and oscillation and predict that such devices could exhibit extraordinary performance.
-------------------------------------------------------------------------------Record 7 of 15
Author(s): [Anon]
Title: Nonlinear optics measure phase-velocity distribution
Source: LASER FOCUS WORLD, 44 (5): 13-13 MAY 2008
-------------------------------------------------------------------------------Record 8 of 15
Author(s): Fondum, TN (Fondum, Timothy N.); Green, KA (Green, Katy A.); Randles, MD (Randles, Michael D.);
Cifuentes, MP (Cifuentes, Marie P.); Willis, AC (Willis, Anthony C.); Teshome, A (Teshome, Ayele); Asselberghs, I
(Asselberghs, Inge); Clays, K (Clays, Koen); Humphrey, MG (Humphrey, Mark G.)
Title: Organometallic complexes for nonlinear optics. 41: Syntheses and quadratic NLO properties of 4-{4-(4nitrophenyl)diazophenyl}ethynylphenylethynyl complexes
Source: JOURNAL OF ORGANOMETALLIC CHEMISTRY, 693 (8-9): 1605-1613 APR 15 2008
Abstract:
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The syntheses of [Au(C C-4-C6H4C C-4-C6H4N=N-4-C6H4NO2)(PPh3)] (3), trans-[Ru(C C-4-C6H4-C C-4C6H4N=N-4-C6H4NO2)Cl(dppm)(2)] (4), [Ru(C C-4-C6H4C C-4-C6H4N=N-4-C6H4NO2)(dppe)(eta-C5Me5)] (5),
and [Ni(C C-4-C6H4N=N-4-C6H4NO2)(PPh3)(eta-C5H5)] (6) are reported, together with a single-crystal X-ray
diffraction study of 4. Quadratic nonlinearities for 3-6 and [Ru(C C-4-C6H4NO2)(dppe)(eta-C5Me5)] (7) have been
determined at 1.064 mu m and 1.300 mu m by the hyper-Rayleigh scattering (HRS) technique, comparison to related
complexes revealing that beta values increase on introduction of azo group and pi-system lengthening. (C) 2007
Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 9 of 15
Author(s): Adles, EJ (Adles, E. J.); Aspnes, DE (Aspnes, D. E.)
Title: The anisotropic bond model of nonlinear optics
Source: PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE, 205 (4): 728-731 APR 2008
Abstract:
The anisotropic-bond model (ABM) of nonlinear optics (NLO) provides a simple means of calculating NLO properties
of materials by factoring the problem into four parts: first, determination of the local field at a bond-charge site; second,
solution of the anharmonic force equation of the bond charge; third, calculation of the radiation from the charge; and
fourth, superposition of the radiation from all charges. Because this factorization is impossible in linear optics, this is
one of the few cases where a nonlinear problem is simpler than its linear equivalent. (C) 2008 WILEY-VCH Verlag
GmbH & Co. KGaA, Weinheim.
-------------------------------------------------------------------------------Record 10 of 15
Author(s): Pasquazi, A (Pasquazi, Alessia); Stivala, S (Stivala, Salvatore); Assanto, G (Assanto, Gaetano); Gonzalo, J
(Gonzalo, Jose); Solis, J (Solis, Javier)
Title: Transverse nonlinear optics in heavy-metal-oxide glass - art. no. 043808
Source: PHYSICAL REVIEW A, 77 (4): 3808-3808 APR 2008
Abstract:
We investigate beam propagation in a heavy-metal-oxide glass of the group Nb2O5-PbO-GeO2 using picosecond pulses
in the near infrared. We observe a wavelength-dependent self-focusing, with beam collapse and modulation instability
in the Kerr regime at 1.064 mu m and stable spatial solitons at 820 nm where multiphoton absorption is present. We
report near-infrared beam self-confinement and solitons, filamentation, interactions, and conical emission in the ps
regime and discuss them with the aid of a numerical model.
-------------------------------------------------------------------------------Record 11 of 15
Author(s): Kim, AV (Kim, A. V.); Skobelev, SA (Skobelev, S. A.); Anderson, D (Anderson, D.); Hansson, T (Hansson,
T.); Lisak, M (Lisak, M.)
Title: Extreme nonlinear optics in a Kerr medium: Exact soliton solutions for a few cycles - art. no. 043823
Source: PHYSICAL REVIEW A, 77 (4): 3823-3823 APR 2008
Abstract:
Exact soliton solutions containing only a few cycles are found within the framework of a nonlinear full wave equation in
a Kerr medium. It is proven numerically that they are stable and play a fundamental role in the pulse propagation
dynamics. These wave solitons cover the range from the fundamental Schrodinger solitons, which occur for long pulses
involving many field oscillations, to extremely short pulses, which contain only one optical period.
-------------------------------------------------------------------------------Record 12 of 15
Author(s): Klingshirn, C (Klingshirn, C.); Fallert, J (Fallert, J.); Gogolin, O (Gogolin, O.); Wissinger, M (Wissinger,
M.); Hauschild, R (Hauschild, R.); Hauser, M (Hauser, M.); Kalt, H (Kalt, H.); Zhou, H (Zhou, H.)
Title: Linear and nonlinear optics, dynamics, and lasing in ZnO bulk and nanostructures
Source: JOURNAL OF LUMINESCENCE, 128 (5-6): 792-796 MAY-JUN 2008
Abstract:
In linear optics, we report on measurements of the absolute external quantum efficiency of bulk ZnO and powders using
an integrating sphere. At low temperature the near band edge emission efficiency can reach 0.15 in the best samples. For
deep center luminescence this value may be even higher. When going to room temperature (RT) the quantum efficiency
drops by about one order of magnitude. From time resolved luminescence measurements we deduce the lifetime of the
free and bound excitons to be in the sub ns regime and find for the latter a systematic increase with increasing binding
energy.
Concerning lasing, we discuss the role of excitonic processes and the recombination in an inverted electron-hole plasma
(EHP). While excitonic processes seem well justified at lower temperatures and densities, doubts arise concerning the
concept of excitonic lasing at RT in ZnO. The densities at laser threshold at RT are frequently close to the Mott density
or above but below the density at which population inversion in an EHP is reached. We suggest alternative processes
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which can explain stimulated emission in this density regime in an EHP at RT. (C) 2007 Elsevier B.V. All rights
reserved.
-------------------------------------------------------------------------------Record 13 of 15
Author(s): Bhagwat, AR (Bhagwat, Amar R.); Gaeta, AL (Gaeta, Alexander L.)
Title: Nonlinear optics in hollow-core photonic bandgap fibers
Source: OPTICS EXPRESS, 16 (7): 5035-5047 MAR 31 2008
Abstract:
Hollow-core photonic-bandgap fibers provide a new geometry for the realization and enhancement of many nonlinear
optical effects. Such fibers offer novel guidance and dispersion properties that provide an advantage over conventional
fibers for various applications. In this review we summarize the nonlinear optics experiments that have been performed
using these hollow-core fibers. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 14 of 15
Author(s): Diemer, V (Diemer, Vincent); Chaumeil, H (Chaumeil, Helene); Defoin, A (Defoin, Albert); Fort, A (Fort,
Alain); Boeglin, A (Boeglin, Alex); Carre, C (Carre, Christiane)
Title: Syntheses of sterically hindered zwitterionic pyridinium phenolates as model compounds in nonlinear optics
Source: EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, (10): 1767-1776 APR 2008
Abstract:
Pyridinium phenolates possess a dissymmetric delocalised pi-electron system providing a huge quadratic nonlinearity.
They are a promising class of molecules for applications in photoelectronics and photonics. Semiempirical calculations
indicate that the interplanar angle between the two aromatic rings leads to enhancement in the NLO properties of these
compounds. The confirmation of this feature may be provided by the study of a new series of sterically hindered
pyridinium phenolates 2a-e bearing two tert-butyl substituents at the ortho position(s) of the phenolate functionality.
Such bulky groups would enhance the solubility of zwitterions in organic solvents and would limit the formation of
aggregates. Their efficient preparations by using Suzuki cross-coupling reactions involving 3,5-dialkylated 4bromopyridine N-oxides are described herein. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2008).
-------------------------------------------------------------------------------Record 15 of 15
Author(s): Faccio, D (Faccio, D.); Di Trapani, P (Di Trapani, P.)
Title: Conical-wave nonlinear optics: From Raman conversion to extreme UV generation
Source: LASER PHYSICS, 18 (3): 253-262 MAR 2008
Abstract:
Conical waves (CW) are a particular class of wavepackets that exhibit the notable feature of being stationary solutions
for both linear and nonlinear propagation equations. The possibility of independently tuning the phase and group
velocities of a CW is a unique feature that opens the possibility of a number of applications, in particular, we shall
consider frequency conversion processes and divide the discussion into two parts: group velocity (GV)-matched and
phase-matched nonlinear processes. As a GV-matched process, we consider stimulated raman scattering within optical
filaments and we highlight the role of cross-phase modulation in the formation of GV-matched X-wave pulses, leading
to high Raman conversion efficiencies and the formation of 15-fs compressed pulses. Conical waves, in particular,
pulsed-Bessel beams, are then considered for phase-matching higher-order harmonic generation in the extreme UV
region.
Space Optical System
Record 1 of 20
Author(s): Hofmann, M (Hofmann, M.); Hauguth-Frank, S (Hauguth-Frank, S.); Lebedev, V (Lebedev, V.); Ambacher,
O (Ambacher, O.); Sinzinger, S (Sinzinger, S.)
Title: Sapphire-GaN-based planar integrated free-space optical system
Source: APPLIED OPTICS, 47 (16): 2950-2955 JUN 1 2008
Abstract:
We report on the design and fabrication of a planar integrated free-space optical system working on the basis of binary
phase diffractive optical elements (DOEs) realized in GaN on a sapphire substrate. Group III-nitride/sapphire substrates
enable the parallel monolithic integration of passive microoptical elements like lenses and gratings as demonstrated here
and optoelectronic devices like light emitters and photodetectors on a single wafer. We present an approach for the
simultaneous optimization of the efficiency of transmissive and reflective diffractive optical elements processed in a
single lithographic etching step. (C) 2008 Optical Society of America.
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-------------------------------------------------------------------------------Record 2 of 20
Author(s): Eigenwillig, CM (Eigenwillig, Christoph M.); Biedermann, BR (Biedermann, Benjamin R.); Palte, G (Palte,
Gesa); Huber, R (Huber, Robert)
Title: K-space linear Fourier domain mode locked laser and applications for optical coherence tomography
Source: OPTICS EXPRESS, 16 (12): 8916-8937 JUN 9 2008
Abstract:
We report on a Fourier Domain Mode Locked (FDML) wavelength swept laser source with a highly linear timefrequency sweep characteristic and demonstrate OCT imaging without k-space resampling prior to Fourier
transformation. A detailed theoretical framework is provided and different strategies how to determine the optimum
drive waveform of the piezo-electrically actuated optical bandpass-filter in the FDML laser are discussed. An FDML
laser with a relative optical frequency deviation Delta v/v smaller than 8.10(-5) over a 100 nm spectral bandwidth at
1300 nm is presented, enabling high resolution OCT over long ranging depths. Without numerical time-to-frequency
resampling and without spectral apodization a sensitivity roll off of 4 dB over 2 mm, 12.5 dB over 4 mm and 26.5 dB
over 1 cm at 3.5 mu s sweep duration and 106.6 dB maximum sensitivity at 9.2 mW average power is achieved. The
axial resolution in air degrades from 14 to 21 mu m over 4 mm imaging depth. The compensation of unbalanced
dispersion in the OCT sample arm by an adapted tuning characteristic of the source is demonstrated. Good stability of
the system without feedback-control loops is observed over hours. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 3 of 20
Author(s): Yan, HW (Yan, Hongwei); Cheng, K (Cheng, Ke); Lu, BD (Lue, Baida)
Title: Composite optical vortices in two noncollinear cosh-Gaussian vortex beams and their propagation properties in
free space
Source: OPTICS AND LASER TECHNOLOGY, 40 (7): 967-977 OCT 2008
Abstract:
The composite optical vortices (OVs) formed by superimposing two parallel, noncollinear cosh-Gaussian (ChG) vortex
beams at the waist plane and their propagation in free space are studied. The dependence of the number, position and net
topological charge of composite OVs on the control parameter, such as the relative phase, amplitude ratio, waist-width
ratio, relative off-axis distance and decentered parameter, and on the propagation distance is illustrated numerically. A
comparison with the previous work is also made. (C) 2008 Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 4 of 20
Author(s): Abdalla, FB (Abdalla, F. B.); Amara, A (Amara, A.); Capak, P (Capak, P.); Cypriano, ES (Cypriano, E. S.);
Lahav, O (Lahav, O.); Rhodes, J (Rhodes, J.)
Title: Photometric redshifts for weak lensing tomography from space: the role of optical and near infrared photometry
Source: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 387 (3): 969-986 JUL 1 2008
Abstract:
We study in detail the photometric redshift requirements needed for tomographic weak gravitational lensing in order to
measure accurately the dark energy equation of state. In particular, we examine how ground-based photometry (u, g, r, i,
z, y) can be complemented by space-based near-infrared (near-IR) photometry (J, H), e.g. onboard the planned DUNE
satellite. Using realistic photometric redshift simulations and an artificial neural network photo-z method we evaluate
the figure of merit for the dark energy parameters (w(0), w(a)). We consider a DUNE-like broad optical filter
supplemented with ground-based multiband optical data from surveys like the Dark Energy Survey, Pan-STARRS and
LSST. We show that the dark energy figure of merit would be improved by a factor of 1.3-1.7 if IR filters are added
onboard DUNE. Furthermore we show that with IR data catastrophic photo-z outliers can be removed effectively. There
is an interplay between the choice of filters, the magnitude limits and the removal of outliers. We draw attention to the
dependence of the results on the galaxy formation scenarios encoded into the mock galaxies, e.g. the galaxy reddening.
For example, very deep u-band data could be as effective as the IR. We also find that about 10(5)-10(6) spectroscopic
redshifts are needed for calibration of the full survey.
-------------------------------------------------------------------------------Record 5 of 20
Author(s): Labadie, L (Labadie, L.); Kern, P (Kern, P.); Labeye, P (Labeye, P.); LeCoarer, E (LeCoarer, E.); VigreuxBercovici, C (Vigreux-Bercovici, C.); Pradel, A (Pradel, A.); Broquin, JE (Broquin, J. -E.); Kirschner, V (Kirschner, V.)
Title: Technology challenges for space interferometry: The option of mid-infrared integrated optics
Source: ADVANCES IN SPACE RESEARCH, 41 (12): 1975-1982 2008
Abstract:
Nulling interferometry is a technique providing high angular resolution which is the core of the space missions Darwin
and TPF. The first objective is to reach a deep degree of starlight cancelation in the range 6-20 mu m, in order to
observe and to characterize the signal from an earth-like planet. Among the numerous technological challenges involved
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in these missions, the question of the beam combination and wavefront filtering has an important place. A single-mode
integrated optics (IO) beam combiner could support both the functions of filtering and the interferometric combination,
simplifying the instrumental design. Such a perspective has been explored in this work within the project Integrated
Optics for Darwin (IODA), which aims at developing a first 10 combiner in the mid-infrared. The solutions reviewed
here to manufacture the combiner here are based on infrared dielectric materials on one side, and on metallic conductive
waveguides on the other side. With this work, additional inputs are offered to pursue the investigation on mid-infrared
photonics devices. (C) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 6 of 20
Author(s): Liu, YD (Liu, Yi-Dong); Gao, CQ (Gao, Chunqing); Qi, XQ (Qi, Xiaoqing); Weber, H (Weber, Horst)
Title: Orbital angular momentum (OAM) spectrum correction in free space optical communication
Source: OPTICS EXPRESS, 16 (10): 7091-7101 MAY 12 2008
Abstract:
Orbital angular momentum (OAM) of laser beams has potential application in free space optical communication, but it
is sensitive against pointing instabilities of the beam, i. e. shift (lateral displacement) and tilt (deflection of the beam).
This work proposes a method to correct the distorted OAM spectrum by using the mean square value of the orbital
angular momentum as an indicator. Qualitative analysis is given, and the numerical simulation is carried out for
demonstration. The results show that the mean square value can be used to determine the beam axis of the superimposed
helical beams. The initial OAM spectrum can be recovered. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 7 of 20
Author(s): Anguita, JA (Anguita, Jaime A.); Neifeld, MA (Neifeld, Mark A.); Vasic, BV (Vasic, Bane V.)
Title: Turbulence-induced channel crosstalk in an orbital angular momentum-multiplexed free-space optical link
Source: APPLIED OPTICS, 47 (13): 2414-2429 MAY 1 2008
Abstract:
A multichannel free-space optical (FSO) communication system based on orbital angular momentum (OAM)-carrying
beams is studied. We numerically analyze the effects of atmospheric turbulence on the system and find that turbulence
induces attenuation and crosstalk among channels. Based on a model in which the constituent channels are binary
symmetric and crosstalk is a Gaussian noise source, we find optimal sets of OAM states at each turbulence condition
studied and determine the aggregate capacity of the multichannel system at those conditions. OAM-multiplexed FSO
systems that operate in the weak turbulence regime are found to offer good performance. We verify that the aggregate
capacity decreases as the turbulence increases. A per-channel bit-error rate evaluation is presented to show the uneven
effects of crosstalk on the constituent channels. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 8 of 20
Author(s): Charbonneau-Lefort, M (Charbonneau-Lefort, Mathieu); Afeyan, B (Afeyan, Bedros); Fejer, MM (Fejer, M.
M.)
Title: Optical parametric amplifiers using nonuniform quasi-phase-matched gratings. II. Space-time evolution of light
pulses
Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (5): 680-697 MAY
2008
Abstract:
Optical parametric amplifiers using chirped quasi-phase-matching gratings offer gain over wide bandwidths, making
them promising candidates for use in ultra-short-pulse laser systems. We discuss the space-time evolution of the
amplified light pulses. In the case of a linear phase-matching profile, this problem is exactly solvable. The Green's
functions of the system are investigated in detail and used to calculate the pulse shapes in the long- and short-pulse
regimes. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 9 of 20
Author(s): Ida, K (Ida, K.); Sakamoto, Y (Sakamoto, Y.); Yoshinuma, M (Yoshinuma, M.); Inagaki, S (Inagaki, S.);
Kobuchi, T (Kobuchi, T.); Matsunaga, G (Matsunaga, G.); Koide, Y (Koide, Y.)
Title: Measurement of derivative of ion temperature using high spatial resolution charge exchange spectroscopy with
space modulation optics - art. no. 053506
Source: REVIEW OF SCIENTIFIC INSTRUMENTS, 79 (5): 53506-53506 MAY 2008
Abstract:
A new technique to measure the first and second derivatives of the ion temperature profile has been developed by using
a charge exchange spectroscopy system with space modulation optics. The space observed is scanned up to +/- 3 cm
with a cosine wave modulation frequency up to 30 Hz by shifting the object lens in front of the optical fiber bundle by
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0.5 mm with a piezoelement. The first and second derivatives of ion temperature are derived from the modulation
component of the ion temperature measured by using Fourier series expansion. (c) 2008 American Institute of Physics.
-------------------------------------------------------------------------------Record 10 of 20
Author(s): Plett, M (Plett, Mark); Rabinovich, WS (Rabinovich, William S.); Mahon, R (Mahon, Rita); Ferraro, MS
(Ferraro, Mike S.); Goetz, PG (Goetz, Peter G.); Moore, CI (Moore, Christopher I.); Freeman, W (Freeman, Wade)
Title: Free-space optical communication link across 16 kilometers over the Chesapeake Bay to a modulated
retroreflector array - art. no. 045001
Source: OPTICAL ENGINEERING, 47 (4): 45001-45001 APR 2008
Abstract:
This paper presents the results of a successful bidirectional free-space optical link across 16 km to a modulated
retroreflector array. The link was implemented at the Naval Research Laboratory's Chesapeake Bay Detachment laser
test range. A 6-W cw 1550-nm class 1 M interrogation beam was used to illuminate an array of three modulated cat'seye retroreflectors located on a tower across the Chesapeake Bay on Tilghman Island. The modulated retroreflectors had
a diameter of 16 mm and were arranged in a triangular pattern with a spacing of 30 cm. The interrogating terminal
employed a 100-mu rad divergence and a high-speed pointing and tracking system to maintain link alignment. Link
testing occurred over 12 days in the months of September, October, and November of 2006. Topics presented in this
paper include the link scenario for the 16-km free-space optical link, the link budget, and terminal designs, as well as
link acquisition and performance. Link performance results presented include data transmission throughput, scintillation
data, and pointing and tracking results. (C) 2008 Society of Photo-Optical Instrumentation Engineers.
-------------------------------------------------------------------------------Record 11 of 20
Author(s): Giggenbach, D (Giggenbach, Dirk); Henniger, H (Henniger, Hennes)
Title: Fading-loss assessment in atmospheric free-space optical communication links with on-off keying - art. no.
046001
Source: OPTICAL ENGINEERING, 47 (4): 46001-46001 APR 2008
Abstract:
Link-budget calculations are a common way to assess system parameters, such as the required transmitter power and
receiver sensitivity, in free-space optical (FSO) communication systems. One of the biggest challenges for long-range
FSO deployment is its signal propagation under turbulent atmospheric conditions, which produce intensity fluctuations.
Methods to estimate atmospheric-fading loss in radio-frequency systems cannot be adapted to the FSO channel. Until
now no general closed-form methods have been developed to describe the fading loss in such a channel. A method to
calculate the losses due to scintillation fading in the threshold approach, based on lognormal statistics of the received
power, is presented. (C) 2008 Society of Photo-Optical Instrumentation Engineers.
-------------------------------------------------------------------------------Record 12 of 20
Author(s): Cheng, K (Cheng Ke); Liu, PS (Liu Pu-Sheng); Lue, BD (Lue Bai-Da)
Title: Composite optical vortices in noncollinear Laguerre-Gaussian beams and their propagation in free space
Source: CHINESE PHYSICS B, 17 (5): 1743-1751 MAY 2008
Abstract:
Taking two Laguerre-Gaussian beams with topological charge l=+/-1 as an example, this paper studies the composite
optical vortices formed by two noncollinear Laguerre-Gaussian beams with different phases, amplitudes, waist widths,
off-axis distances, and their propagation in free space. It is shown by detailed numerical illustrative examples that the
number and location of composite vortices at the waist plane are variable by varying the relative phase beta, amplitude
ratio eta, waist width ratio xi, or off-axis distance ratio mu. The net topological charge l(net) is not always equal to the
sum l(sum) of charges of the two component beams. The motion, creation and annihilation of composite vortices take
place in the free-space propagation, and the net charge during the propagation remains unchanged and equals to the net
charge at the waist plane.
-------------------------------------------------------------------------------Record 13 of 20
Author(s): Slavnov, SG (Slavnov, S. G.)
Title: Optical sensor of the position of an object in space and facilities for monitoring it
Source: JOURNAL OF OPTICAL TECHNOLOGY, 75 (4): 247-249 APR 2008
Abstract:
This paper describes a method of constructing an optical sensor of the position of an object in space and facilities for
monitoring it. The method is based on a technique for forming plane and solid angles of a light beam formed by a set of
rays issuing from an active area of limited size. Schematic optical diagrams are given for the sensor and monitoring
facilities, and analytical expressions are proposed for computing the coordinates of an object. The monitoring facilities
make it possible take into account the error of operating the source while measurements of the coordinate of an object
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are being made. Results of an experiment are presented for a case in which the angular and linear coordinates are
visually estimated to within 3 '' and 0.07 mm, respectively. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 14 of 20
Author(s): Hu, ZP (Hu, Ziping); Verma, P (Verma, Pramode); Sluss, J (Sluss, James, Jr.)
Title: Improved reliability of free-space optical mesh networks through topology design
Source: JOURNAL OF OPTICAL NETWORKING, 7 (5): 436-448 MAY 1 2008
Abstract:
We propose a method for the topology design of free-space optical (FSO) mesh networks in order to enhance network
reliability under a defined degree constraint of each FSO node. The methodology presented enlarges the minimum angle
between adjacent links at each node. Simulation results show that, compared to other methods, the proposed algorithm
not only provides a higher connectivity and lower delay for FSO networks but also makes the constructed FSO networks
more tolerant in a dynamic environment. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 15 of 20
Author(s): Escudero-Sanz, I (Escudero-Sanz, Isabel); Ahlers, B (Ahlers, Berit); Courreges-Lacoste, GB (CourregesLacoste, Gregory Bazalgette)
Title: Optical design of a combined Raman-laser-induced-breakdown-spectroscopy instrument for the European Space
Agency ExoMars Mission - art. no. 033001
Source: OPTICAL ENGINEERING, 47 (3): 33001-33001 MAR 2008
Abstract:
Among the different instruments that have been selected for the Pasteur payload on ExoMars is the Raman - laserinduced-breakdown-spectroscopy ( LIBS ) instrument. The novel, and technologically challenging, feature of this
instrument is the integration of both Raman spectroscopy and LIBS techniques in the same hardware. An international
team under the lead of TNO has been gathered together to produce a combined Raman- spectrometer - LIBS elegant
breadboard. The instrument has been designed around an extremely compact spectrometer with a high resolution over a
large wavelength range, which is suitable for both Raman spectroscopy and LIBS measurements. Low mass, size, and
power consumption are the main drivers of the instrument design concept. A summary of the functional and
environmental requirements together with a description of the optical design and its performance are included. (C) 2008
Society of Photo- Optical Instrumentation Engineers.
-------------------------------------------------------------------------------Record 16 of 20
Author(s): Al Naboulsi, M (Al Naboulsi, Maher); de Fornel, F (de Fornel, Frederique); Sizun, H (Sizun, Herve);
Gebhart, M (Gebhart, Michael); Leitgeb, E (Leitgeb, Erich); Muhammad, SS (Muhammad, Sajid Sheikh); Flecker, B
(Flecker, Benno); Chlestil, C (Chlestil, Christoph)
Title: Measured and predicted light attenuation in dense coastal upslope fog at 650, 850, and 950 nm for free-space
optics applications - art. no. 036001
Source: OPTICAL ENGINEERING, 47 (3): 36001-36001 MAR 2008
Abstract:
Free-space optics (FSO) has gained considerable importance in this decade of demand for high-bandwidth transmission
capabilities. FSO can provide the last mile solution, but the availability and reliability issues concerned with it have
received increasing attention and need thorough investigation. In this work, we present our results on fog attenuation
measurement and prediction at wavelengths 650, 850, and 950 nm with peak values up to 500 dB/km. For the
attenuation measurement, optical wavelengths are transmitted over the same path of fog in free air to a receiver,
measuring the power at every wavelength. The measurement of fog attenuation was performed at the France Telecom
R&D test facility at La Turbie (in the south of France). We compare our measurement data with the commonly used
light attenuation models (Kruse and Kim models) and with a new proposed model allowing the prediction of fog
attenuation for the 0.69- to 1.55-mu m spectral band. We present some interesting insights and discuss the wavelength
dependence. The practical measurements described promise to validate the models and therefore should lead to more
accurate availability prediction for FSO links. (C) 2008 Society of Photo-Optical Instrumentation Engineers.
-------------------------------------------------------------------------------Record 17 of 20
Author(s): Choi, H (Choi, Hyunhee); Woo, JH (Woo, J. H.); Wu, JW (Wu, J. W.)
Title: Ladder operators formalism for optical angular momentum transfer and space-variant Pancharatnam-Berry phase
Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (4): 491-494 APR 2008
Abstract:
Ladder operators are introduced in SU(2) parameter space to analyze the space-variant Pancharatnam-Berry (PB) phase.
The spin and orbital angular momentum transfers to a wave passing through the PB phase optical elements are
understood in terms of the PB phase. Space-variant PB phase structures are identified in polarization grating and
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cholesteric liquid crystal, providing an explanation for the beam propagation direction alteration. A simultaneous
occurrence of the wavefront shaping and the beam propagation direction alteration is demonstrated experimentally. (C)
2008 Optical Society of America.
-------------------------------------------------------------------------------Record 18 of 20
Author(s): Cvijetic, N (Cvijetic, Neda); Wilson, SG (Wilson, Stephen G.); Brandt-Pearce, M (Brandt-Pearce, Maite)
Title: Performance bounds for free-space optical MIMO systems with APD receivers in atmospheric turbulence
Source: IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, 26 (3): 3-12 Suppl. S APR 2008
Abstract:
Performance bounds of free space optical (FSO) systems with multiple laser transmitters and multiple avalanche
photodetectors (APDs) are evaluated for terrestrial, line-of-sight communication. Specifically, analytical upper bounds
on average uncoded error rate in turbulent multiple-input multiple-output (MIMO) channels with Q-ary pulse position
modulation (PPM) are derived for arbitrary observable densities, and are used to quantify APD-based performance
improvements over pin detector arrays in non-fading, lognormal, and negative exponential channels. Moreover, it is
shown that despite the high complexity of APD array statistics, these performance gains can be accurately predicted
using a jointly-Gaussian model for APD array outputs. Both maximum likelihood (ML) and sub-optimal combining
rules are derived, and a simple equal gain combiner (EGC) that performs close to optimum is demonstrated. Finally,
APD gain selection is discussed.
-------------------------------------------------------------------------------Record 19 of 20
Author(s): Flohrer, T (Flohrer, T.); Schildknecht, T (Schildknecht, T.); Musci, R (Musci, R.)
Title: Proposed strategies for optical observations in a future European Space Surveillance network
Source: ADVANCES IN SPACE RESEARCH, 41 (7): 1010-1021 2008
Abstract:
Two ESA-funded feasibility studies that aimed to develop observation strategies, to propose suitable sensor
architectures, and to assess the expected performance of an independent European Space Surveillance System were
carried out during the last years. The French company ONERA led two study teams comprising a number of European
companies.
The proposed space surveillance system consists of two subsystems, a phased-array radar system that shall be located in
the South of Spain, and a network of ground-based electro-optical telescopes at four low latitude sites. This system
allows to build-up and to maintain a catalogue of orbital elements of objects in space. It provides means to perform
additional space surveillance tasks such as independent detection of fragmentation events, launches or manoeuvres, and
allows to acquire the necessary measurements to assess the collision risk between catalogued objects.
As a member of both study teams, the Astronomical Institute of the University of Bern (AIUB), Switzerland,
contributed to the observation strategy definition, the system design, and the performance estimation of the optical
observation part of the space surveillance system. This part of the system is intended to cover the Geostationary Orbit
(GEO) and the Medium Earth Orbit (MEO) regions.
This paper focuses on the development and evaluation of observation strategies for GEO and MEO within a space
surveillance network. Observation requirements, possible strategies fulfilling the requirements, and the expected
performance of selected strategies in terms of the coverage of a reference population are addressed.
We conclude that GEO and MEO shall be covered by "stripe-scanning" approaches carried out by a network of
telescopes. The simulations of the approaches using a reference population reveal that for both regions a nearly
complete coverage can be guaranteed within a short time. (C) 2007 COSPAR. Published by Elsevier Ltd. All rights
reserved.
-------------------------------------------------------------------------------Record 20 of 20
Author(s): Molotov, I (Molotov, I.); Agapov, V (Agapov, V.); Titenko, V (Titenko, V.); Khutorovsky, Z (Khutorovsky,
Z.); Burtsev, Y (Burtsev, Yu.); Guseva, I (Guseva, I.); Rumyantsev, V (Rumyantsev, V.); Ibrahimov, M (Ibrahimov,
M.); Kornienko, G (Kornienko, G.); Erofeeva, A (Erofeeva, A.); Biryukov, V (Biryukov, V.); Vlasjuk, V (Vlasjuk, V.);
Kiladze, R (Kiladze, R.); Zalles, R (Zalles, R.); Sukhov, P (Sukhov, P.); Inasaridze, R (Inasaridze, R.); Abdullaeva, G
(Abdullaeva, G.); Rychalsk, V (Rychalsk, V.); Kouprianov, V (Kouprianov, V.); Rusakov, O (Rusakov, O.); Litvinenko,
E (Litvinenko, E.); Filippov, E (Filippov, E.)
Title: International scientific optical network for space debris research
Source: ADVANCES IN SPACE RESEARCH, 41 (7): 1022-1028 2008
Abstract:
A joint team of researchers under the auspices of the Center for Space Debris Information Collection, Processing and
Analysis of the Russian Academy of Sciences collaborates with 15 observatories around the world to perform
observations of space debris. For this purpose, 14 telescopes were equipped with charge-coupled device (CCD) cameras,
Global Positioning System (GPS) receivers, CCD frame processing and ephemeris computation software, with the
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support of the European and Russian grants. Many of the observation campaigns were carried out in collaboration with
the Astronomical Institute of the University of Bern (AIUB) team operating at the Zimmerwald observatory and
conducting research for the European Space Agency (ESA), using the Tenerife/Teide telescope for searching and
tracking of unknown objects in the geostationary region (GEO). More than 130,000 measurements of space objects
along a GEO arc of 340.9 degrees, collected and processed at Space Debris Data Base in the Ballistic Center of the
Keldysh Institute of Applied Mathematics (KIAM) in 2005-2006, allowed us to find 288 GEO objects that are absent in
the public orbital databases and to determine their orbital elements. Methods of discovering and tracking small space
debris fragments at high orbits were developed and tested. About 40 of 150 detected unknown objects of magnitudes 1520.5 were tracked during many months. A series of dedicated 22-cm telescopes with large field of view for GEO survey
tasks is in process of construction. 7 60-cm, telescopes will be modernized in 2007. (C) 2007 COSPAR. Published by
Elsevier Ltd. All rights reserved.
Imaging Spectrometry
Record 1 of 23
Author(s): Aktas, L (Aktas, Levent); Hamidi, YK (Hamidi, Youssef K.); Altan, MC (Altan, M. Cengiz)
Title: Dispersion characterization of nanoclay in molded epoxy disks by combined image analysis and wavelength
dispersive spectrometry - art. no. 031005
Source: JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME,
130 (3): 31005-31005 JUL 2008
Abstract:
The state of nanoclay dispersion in a molded epoxy disk and its effects on the thermomechanical properties of the
resulting nanocomposite are analyzed. A commercially available nanoclay, Cloisite (R) 25A, is mechanically mixed at 2
wt % with EPON 815C epoxy resin. The epoxy/clay compound is then mixed with EPI-CURE 3282 curing agent by a
custom made molding setup and injected into a disk shaped mold cavity. Upon completion of curing, nanoclay
dispersion is quantified on a sample cut along the radius of the composite disk. Dispersion of nanoclay clusters larger
than 1.5 mu m are analyzed by digital image processing of scanning electron micrographs taken radially along the
sample, whereas dispersion at smaller scales is quantified by compositional analysis of clay via wavelength dispersive
spectrometry (WDS). Digital images of the microstructure indicate that amount of nanoclay clusters that are larger than
1.5 mu m remain approximately constant along the radius. However, size analysis of nanoclay clusters revealed that
they are broken down into finer clusters along the radius, possibly due to the high shear deformation induced through
the thickness during mold filling. Compositional analysis by WDS signified that approximately 0.4 wt % of the
nanoclay is dispersed to particles smaller than 1.5 mu m, which are not visible in micrographs. Tensile and three-point
bending tests are conducted on additional samples cut from the molded disks. Except for slight reduction in flexural
strength, up to 9.5% increase in tensile strength, stiffness, and flexural modulus are observed. Glass transition
temperature is determined under oscillatory torsion and observed to increase by 4.5% by the addition of nanoclay.
-------------------------------------------------------------------------------Record 2 of 23
Author(s): Burnum, KE (Burnum, Kristin E.); Tranguch, S (Tranguch, Susanne); Mi, D (Mi, Deming); Daikoku, T
(Daikoku, Takiko); Dey, SK (Dey, S. K.); Caprioli, RM (Caprioli, Richard M.)
Title: Imaging mass spectrometry reveals unique protein profiles during embryo implantation
Source: ENDOCRINOLOGY, 149 (7): 3274-3278 JUL 2008
Abstract:
Areciprocal interaction between the implantation-competent blastocyst and receptive uterus is an absolute requirement
for implantation, a process crucial for pregnancy success. A comprehensive understanding of this interaction has yet to
be realized. One major difficulty in clearly defining this discourse is the complexity of the implantation process
involving heterogeneous cell types of both the uterus and blastocyst, each endowed with unique molecular signatures
that show dynamic changes during the course of pregnancy. Whereas gene expression studies by in situ hybridization or
immunohistochemistry have shown differential expression patterns of specific genes during implantation, there is no
report how numerous signaling proteins are spatially displayed at specific times and stages of implantation in the
context of blastocyst-uterine juxtaposition. Using in situ imaging (matrix assisted laser desorption/ionization) mass
spectrometry directly on uterine sections, here we provide molecular composition, relative abundance, and spatial
distribution of a large number of proteins during the periimplantation period. This approach has allowed us for the first
time to generate in situ proteome profiles of implantation and interimplantation sites in mice in a region- and stagespecific manner with the progression of implantation. This application is reliable because patterns of expression of
several proteins displayed by in situ imaging mass spectrometry correlate well with in situ hybridization results. More
interestingly, the use of this approach has provided new insights regarding uterine biology of cytosolic phospholipase
A(2 alpha) null females that show implantation defects.
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Author(s): Nemes, P (Nemes, Peter); Barton, AA (Barton, Alexis A.); Li, Y (Li, Yue); Vertes, A (Vertes, Akos)
Title: Ambient molecular imaging and depth profiling of live tissue by infrared laser ablation electrospray ionization
mass spectrometry
Source: ANALYTICAL CHEMISTRY, 80 (12): 4575-4582 JUN 15 2008
Abstract:
Mass spectrometry in conjunction with atmospheric pressure ionization methods enables the in vivo investigation of
biochemical changes with high specificity and sensitivity. Laser ablation electrospray ionization (LAESI) is a recently
introduced ambient ionization method suited for the analysis of biological samples with sufficient water content With
LAESI mass spectrometric analysis of chimeric Aphelandra squarrosa leaf tissue, we identify the metabolites
characteristic for the green and yellow sectors of variegation. Significant parts of the related biosynthetic pathways (e.g.,
kaempferol biosynthesis) are ascertained from the detected metabolites and metabolomic databases. Scanning electron
microscopy of the ablated areas indicates the feasibility of both two-dimensional imaging and depth profiling with a
similar to 350 mu m lateral and similar to 50 mu m depth resolution. Molecular distributions of some endogenous
metabolites show chemical contrast between the sectors of variegation and quantitative changes as the ablation reaches
the epidermal and mesophyll layers. Our results demonstrate that LAESI mass spectrometry opens a new way for
ambient molecular imaging and depth profiling of metabolites in biological tissues and live organisms.
-------------------------------------------------------------------------------Record 4 of 23
Author(s): Grey, AC (Grey, Angus C.); Schey, KL (Schey, Kevin L.)
Title: Distribution of bovine and rabbit lens alpha-crystallin products by MALDI imaging mass spectrometry
Source: MOLECULAR VISION, 14 (19-23): 171-179 JAN 29 2008
Abstract:
Purpose: To develop a general tissue preparation protocol for MALDI (Matrix-Assisted Laser Desorption Ionization)
imaging mass spectrometry of ocular lens tissue, and to compare the spatial distributions of alpha-crystallin and its
modified forms in bovine and rabbit lenses.
Methods: Frozen bovine and rabbit lenses were cryosectioned equatorially at -20 degrees C into 12 mu m-thick tissue
sections. Lens sections were mounted onto conductive glass slides by ethanol soft-landing to maintain tissue integrity.
An ethanol/xylene washing procedure was applied to each section before matrix application to facilitate uniform matrix
crystal formation across the entire tissue section. Molecular images of both alpha-crystallin subunits and their modified
forms were obtained from mass spectral data acquired at 100 mu m steps across both whole rabbit and half bovine lens
sections.
Results: Distinct spatial patterns for the two subunits of alpha-crystallin and their modified forms were observed in the
rabbit and bovine lens sections. While alpha A-crystallin was extensively degraded in the lens core of both species,
rabbit lenses exhibited a greater degree of larger molecular weight truncation products. In contrast, alpha B-crystallin
degradation was limited in both species. Interestingly, phosphorylation of alpha A- and alpha B-crystallin was most
abundant in the middle cortex of both species.
Conclusions: An improved method for investigating the spatial distribution of alpha-crystallin in the ocular lens by
MALDI imaging mass spectrometry has been developed. The localization of multiple degradation products and specific
regions of alpha-crystallin phosphorylation in bovine and rabbit lenses gives new insight into the program of lens fiber
cell differentiation and normal lens function.
-------------------------------------------------------------------------------Record 5 of 23
Author(s): Broersen, A (Broersen, Alexander); van Liere, R (van Liere, Robert); Altelaar, AFM (Altelaar, A. F.
Maarten); Heeren, RMA (Heeren, Ron M. A.); McDonnell, LA (McDonnell, Liam A.)
Title: Automated, feature-based image alignment for high-resolution imaging mass spectrometry of large biological
samples
Source: JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY, 19 (6): 823-832 JUN 2008
Abstract:
High-resolution imaging mass spectrometry of large biological samples is the goal of several research groups. In mosaic
imaging, the most common method, the large sample is divided into a mosaic of small areas that are then analyzed with
high resolution. Here we present an automated alignment routine that uses principal component analysis to reduce the
uncorrelated noise in the imaging datasets, which previously obstructed automated image alignment. An additional
signal quality metric ensures that only those regions with sufficient signal quality are considered. We demonstrate that
this algorithm provides superior alignment performance than manual stitching and can be used to automatically align
large imaging mass spectrometry datasets comprising many individual mosaic tiles.
-------------------------------------------------------------------------------Record 6 of 23
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Author(s): Trim, PJ (Trim, Paul J.); Atkinson, SJ (Atkinson, Sally J.); Princivalle, AP (Princivalle, Alessandra P.);
Marshall, PS (Marshall, Peter S.); West, A (West, Andrew); Clench, MR (Clench, Malcolm R.)
Title: Matrix-assisted laser desorption/ionisation mass spectrometry imaging of lipids in rat brain tissue with integrated
unsupervised and supervised multivariant statistical analysis
Source: RAPID COMMUNICATIONS IN MASS SPECTROMETRY, 22 (10): 1503-1509 MAY 2008
Abstract:
To date matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) analysis has been largely
concerned with mapping the distribution of known analytes in tissues. An important step in the progression of its
applications is the determination of unknown variants for metabolite and protein profiling in both clinical studies and
studies of disease. Principal component analysis (PCA) is a statistical approach which can be used as a means of
determining latent variables in multivariate data sets. In the work reported here, PCA, in both unsupervised and
supervised modes, has been used to differentiate brain regions based on their lipid composition determined by MALDIMSI. PCA has been shown to be useful in the determination of hidden variables between spectra taken from six regions
of brain tissue. It is possible to identify ions of interest from the loadings plot which are likely to be more prominent in
the different regions of the brain and thus differentiating between white and grey matter. It is also possible to distinguish
between the grey Cerebellar Cortex and the Hippocampal formation, due to the grey Cerebellar Cortex having a positive
PC2 and the Hippocampal formation having a negative PC2 score; this is only possible in supervised PCA with this data
set because with unsupervised PCA the two regions overlap. Copyright (C) 2008 John Wiley & Sons, Ltd.
-------------------------------------------------------------------------------Record 7 of 23
Author(s): Djidja, MC (Djidja, Marie-Claude); Carolan, V (Carolan, Vikki); Loadman, PM (Loadman, Paul M.); Clench,
MR (Clench, Malcolm R.)
Title: Method development for protein profiling in biological tissues by matrix-assisted laser desorption/ionisation mass
spectrometry imaging
Source: RAPID COMMUNICATIONS IN MASS SPECTROMETRY, 22 (10): 1615-1618 MAY 2008
-------------------------------------------------------------------------------Record 8 of 23
Author(s): Hardesty, WM (Hardesty, William M.); Caprioli, RM (Caprioli, Richard M.)
Title: In situ molecular imaging of proteins in tissues using mass spectrometry
Source: ANALYTICAL AND BIOANALYTICAL CHEMISTRY, 391 (3): 899-903 JUN 2008
-------------------------------------------------------------------------------Record 9 of 23
Author(s): Harig, R (Harig, Roland); Braun, R (Braun, Rene); Dyer, C (Dyer, Chris); Howle, C (Howle, Chris); Truscott,
B (Truscott, Benjamin)
Title: Short-range remote detection of liquid surface contamination by active imaging Fourier transform spectrometry
Source: OPTICS EXPRESS, 16 (8): 5708-U5 APR 14 2008
Abstract:
An imaging Fourier transform spectrometer developed at TUHH was used for short-range remote detection and
identification of liquids on surfaces. The method is based on the measurement of infrared radiation emitted and reflected
by the surface and the liquid. A radiative transfer model that takes both the real and imaginary parts of the refractive
index of the materials into account has been developed. The model is applied for the detection and identification of
potentially hazardous liquids. Measurements of various liquids on diverse surfaces were performed. The measured
spectra depend on the optical properties of the background surface. However, using the radiative transfer model,
automatic remote detection and identification of the liquids is possible. The agreement between measured spectra and
spectra calculated using the radiative transfer model is excellent. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 10 of 23
Author(s): Chen, YF (Chen, Yanfeng); Allegood, J (Allegood, Jeremy); Liu, Y (Liu, Ying); Wang, E (Wang, Elaine);
Cachon-Gonzalez, B (Cachon-Gonzalez, Begona); Cox, TM (Cox, Timothy M.); Merrill, AH (Merrill, Alfred H., Jr.);
Sullards, MC (Sullards, M. Cameron)
Title: Imaging MALDI mass spectrometry using an oscillating capillary nebulizer matrix coating system and its
application to analysis of lipids in brain from a mouse model of Tay-Sachs/Sandhoff disease
Source: ANALYTICAL CHEMISTRY, 80 (8): 2780-2788 APR 15 2008
Abstract:
The quality of tissue imaging by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) depends
on the effectiveness of the matrix deposition, especially for lipids that may dissolve in the solvent used for the matrix
application. This article describes the use of an oscillating capillary nebulizer (OCN) to spray small droplets of matrix
aerosol onto the sample surface for improved matrix homogeneity, reduced crystal size, and controlled solvent effects.
This system was then applied to the analysis of histological slices of brains from mice with homozygous disruption of
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the hexb gene (hexb(-/-)), a model of Tay-Sachs and Sandhoff disease, versus the functionally normal heterozygote
(hexb(+/-)) by imaging MALDI-MS. This allowed profiling and localization of many different lipid species, and of
particular interest, ganglioside GM2, asialo-GM2 (GA2), and sulfatides (ST). The presence of these compounds was
confirmed by analysis of brain extracts using electrospray ionization in conjunction with tandem mass spectrometry
(MS/MS). The major fatty acid of the ceramide backbone of both GM2 and GA2 was identified as stearic acid (18:0)
versus nervonic acid (24: 1) for ST by both tissue-imaging MS and ESI-MS/MS. GM2 and GA2 were highly elevated in
hexb(-/-) and were both localized in the granular cell region of the cerebellum. ST, however, was localized mainly in
myelinated fiber (white matter) region of the cerebellum as well as in the brain stem with a relatively uniform
distribution and had similar relative signal intensity for both hexb(+/-) and hexb(-/-) brain. It was also observed that
there were distinct localizations for numerous other lipid subclasses; hence, imaging MALDI-MS could be used for
"lipidomic" studies. These results illustrate the usefulness of tissue-imaging MALDI-MS with matrix deposition by
OCN for histologic comparison of lipids in tissues such as brains from this mouse model of Tay-Sachs and Sandhoff
disease.
-------------------------------------------------------------------------------Record 11 of 23
Author(s): Zoriy, MV (Zoriy, Myroslav V.); Dehnhardt, M (Dehnhardt, Markus); Matusch, A (Matusch, Andreas);
Becker, JS (Becker, J. Sabine)
Title: Comparative imaging of P, S, Fe, Cu, Zn and C in thin sections of rat brain tumor as well as control tissues by
laser ablation inductively coupled plasma mass spectrometry
Source: SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY, 63 (3): 375-382 MAR 2008
Abstract:
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used for quantitative imaging of
selected elements (P, S, Fe, Cu, Zn and C) in thin sections of rat brain samples (thickness 20 pm). The sample surface
was scanned (raster area similar to 2 cm(2)) with a focused laser beam (wavelength 266 nm, diameter of laser crater 50
mu m, and irradiance X 10(9) W cm(-2)). The laser ablation system was coupled to a doublefocusing sector field. The
possibility was evaluated of using carbon (via measurement of C-13(+)) as an internal standard element for imaging
element distribution as part of this method. The LA-ICP-MS images obtained for P, S, Fe Cu and Zn were quantified
using synthetically prepared matrixmatched laboratory standards. Depending on the sample analyzed, concentrations of
Cu and Zn in the control, tissue were found to be in the range of 8-10 mu g g(-1) and 10-12 mu g g(-1), while in the
tumor tissue these concentrations were in the range of 12-15 mu g g(-1) and 15-17 mu g g(-1) respectively. The
measurements of P, S and Fe distribution revealed the depletion of these elements in tumor tissue. In all the samples, the
shape of the tumor could be clearly distinguished from the surrounding healthy tissue by the depletion in carbon.
Additional experiments were performed in order to study the influence of the water content of the analyzed tissue on the
intensity signal of the analyte. The results of these measurements show the linear correlation (R-2 = 0.9604) between the
intensity of analyte and amount of water in the sample. The growth of a brain tumor was thus studied for the first time
by imaging mass spectrometry. (c) 2008 Published by Elsevier B.V.
-------------------------------------------------------------------------------Record 12 of 23
Author(s): Wiseman, JM (Wiseman, Justin M.); Ifa, DR (Ifa, Demian R.); Venter, A (Venter, Andre); Cooks, RG
(Cooks, R. Graham)
Title: Ambient molecular imaging by desorption electrospray ionization mass spectrometry
Source: NATURE PROTOCOLS, 3 (3): 517-524 2008
Abstract:
Desorption electrospray ionization (DESI) allows the direct analysis of ordinary objects or pre-processed samples under
ambient conditions. Among other applications, DESI is used to identify and record spatial distributions of lipids and
drug molecules in biological tissue sections. This technique does not require sample preparation other than production
of microtome tissue slices and does not involve the use of ionization matrices. This greatly simplifies the procedure and
prevents the redistribution of analytes during matrix deposition. Images are obtained by continuously moving the
sample relative to the DESI sprayer and the inlet of the mass spectrometer. The timing of the protocol depends on the
size of the surface to be analyzed and on the desired resolution. Analysis of organ tissue slices at 250 mu m resolution
typically takes between 30 min and 2 h.
-------------------------------------------------------------------------------Record 13 of 23
Author(s): Vaidyanathan, S (Vaidyanathan, Seethararnan); Fietcher, JS (Fietcher, John S.); Goodacre, R (Goodacre,
Roy); Lockyer, NP (Lockyer, Nicholas P.); Micklefield, J (Micklefield, Jason); Vickerman, JC (Vickerman, John C.)
Title: Subsurface biomolecular imaging of Streptomyces coelicolor using secondary ion mass spectrometry
Source: ANALYTICAL CHEMISTRY, 80 (6): 1942-1951 MAR 15 2008
Abstract:
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Imaging using time-of-flight secondary ion mass spectrometry (TOF-SIMS) with buckministerfullerene (C-60) primary
ions offers the possibility of mapping the chemical distribution of molecular species from biological surfaces. Here we
demonstrate the capability of the technique to provide biomolecular information from the cell surface as well as from
within the surface, as illustrated with the distribution of two antibiotics in Streptomyces coelicolor (a mycelial
bacterium). Differential production of the two pigmented antibiotics under salt-stressed and normal conditions in
submerged cultivations could be detected from the TOF-SIMS spectra of the bacteria, demonstrating the potential of the
technique in studying microbial physiology. Although both the antibiotics were detected on the cell surface, sputter
etching with C-60(+) revealed the spectral features of only one of the antibiotics within the cells. Exploratory analysis of
the images using principal component analysis assisted in analyzing the spectral information with respect to peak
contributions and their spatial distributions. The technique allows the study of not only lateral but also the depthwise
distribution of biomolecules, uniquely enabling exploration of the processes within biological systems with minimal
system intervention and with little a priori biochemical knowledge of relevance.
-------------------------------------------------------------------------------Record 14 of 23
Author(s): Chaurand, P (Chaurand, Pierre); Rahman, MA (Rahman, Mohammad A.); Hunt, T (Hunt, Tamela); Mobley,
JA (Mobley, James A.); Gu, G (Gu, Guangyu); Latham, JC (Latham, Joey C.); Caprioli, RM (Caprioli, Richard M.);
Kasper, S (Kasper, Susan)
Title: Monitoring mouse prostate development by profiling and imaging mass spectrometry
Source: MOLECULAR & CELLULAR PROTEOMICS, 7 (2): 411-423 FEB 2008
Abstract:
Mass spectrometry-based tissue profiling and imaging are technologies that allow identification and visualization of
protein signals directly on thin sections cut from fresh frozen tissue specimens. These technologies were utilized to
evaluate protein expression profiles in the normal mouse prostate during development (1-5 weeks of age), at sexual
maturation (6 weeks of age), and in adult prostate (at 10, 15, or 40 weeks of age). The evolution of protein expression
during normal prostate development and maturation were subsequently compared with 15-week prostate tumors derived
from genetically engineered mice carrying the Large T antigen gene under regulation of the prostate-specific probasin
promoter (LPB-Tag mouse model for prostate cancer). This approach identified proteins differentially expressed at
specific time points during prostate development. Furthermore expression of some of these proteins, for example
probasin and spermine-binding protein, were associated with prostate maturation, and prostate tumor formation resulted
in their loss of expression. Cyclophilin A, a protein found in other cancers, was differentially a-acetylated on the N
terminus, and both isoforms appeared during normal prostate and prostate tumor development. Imaging mass
spectrometry localized the protein signals to specific prostatic lobes or regions. Thus, tissue profiling and imaging can
be utilized to analyze the ontogeny of protein expression during prostate morphogenesis and tumorigenesis and identify
proteins that could potentially serve as biomarkers for prostate cancer.
-------------------------------------------------------------------------------Record 15 of 23
Author(s): Kertesz, V (Kertesz, Vilmos); van Berkel, GJ (van Berkel, Gary J.)
Title: Scanning and surface alignment considerations in chemical imaging with desorption electrospray mass
spectrometry
Source: ANALYTICAL CHEMISTRY, 80 (4): 1027-1032 FEB 15 2008
Abstract:
The effects of surface scanning mode (raster vs unidirectional scanning) and the constancy of spray tip-to-surface and
atmospheric sampling interface capillary-to-surface distances on chemical image quality using desorption electrospray
ionization mass spectrometry were investigated. Unidirectional scanning was found to provide a spatially and a
quantitatively more precise chemical image of the surface as compared to raster scanning. Maintaining constant spray
tip-to-surface and atmospheric sampling interface capillary-to-surface distances during an imaging experiment was
found to also be critical. An automation process was implemented using a custom image analysis software (HandsFree
Surface Analysis) to keep these distances constant during the surface sampling experiment. Improved chemical image
quality afforded through this software control was illustrated by imaging printed objects on normal copy paper.
-------------------------------------------------------------------------------Record 16 of 23
Author(s): Elbast, M (Elbast, Mouhamad); Wu, TD (Wu, Ting-Di); Guiraud-Vitaux, F (Guiraud-Vitaux, Francoise);
Petiet, A (Petiet, Anne); Hindie, E (Hindie, Elif); Champion, C (Champion, Christophe); Croisy, A (Croisy, Alain);
Guerquin-Kern, JL (Guerquin-Kern, Jean-Luc); Colas-Linhart, N (Colas-Linhart, Nicole)
Title: Kinetics of intracolloidal iodine within the thyroid of newborn rats. Direct imagery using secondary ion mass
spectrometry
Source: COMPTES RENDUS BIOLOGIES, 331 (1): 13-22 JAN 2008
Abstract:
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The spatiotemporal distribution of cellular uptake site of radiotoxics is essential data for microdosimetric studies. As
early as 1950, the heterogeneity of iodine incorporation within the thyroid has been shown using autoradiography. The
objective of this study is to describe the kinetic cellular distribution of newly organified iodine in the thyroid of newborn
rats using secondary ion mass microscopy (NanoSIMS50). Ionic images obtained at high mass resolution and with a
lateral resolution of about 50 nm show that the early distribution of iodine is heterogeneous from one follicle to another,
from one thyrocyte to another inside the same follicle, and that this distribution varies as a function of time. The
obtained kinetic profile will allow us to refine the studies concerning the aetiopathology of thyroid cancers of the
Chernobyl children.
-------------------------------------------------------------------------------Record 17 of 23
Author(s): Dobrowolska, J (Dobrowolska, J.); Dehnhardt, M (Dehnhardt, M.); Matusch, A (Matusch, A.); Zoriy, M
(Zoriy, M.); Palomero-Gallagher, N (Palomero-Gallagher, N.); Koscielniak, P (Koscielniak, P.); Zilles, K (Zilles, K.);
Becker, JS (Becker, J. S.)
Title: Quantitative imaging of zinc, copper and lead in three distinct regions of the human brain by laser ablation
inductively coupled plasma mass spectrometry
Source: TALANTA, 74 (4): 717-723 JAN 15 2008
Abstract:
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to determine the distribution of
the trace elements zinc, copper and lead in insular, central and hippocampal areas of thin tissue sections (thickness 20
mu m) through an entire human brain hemisphere. For the investigation of the tissue samples, a commercial laser
ablation system was coupled to a double-focusing sector field ICP-MS. The regions of interest of healthy brain tissue
(thickness 20 mu m) were scanned (raster area similar to 200 mm(2)) with a focused laser beam (wavelength 266 nm,
diameter of laser crater 200 mu m and laser power density 3 x 10(9) W cm(-2)). The ion intensities of Zn-64(+), Cu63(+) and Pb-208(+) were measured by LA-ICP-MS within the ablated area. For quantification purposes, matrixmatched laboratory standards were prepared by means of dosing of each analyte to the pieces of brain tissue. The mass
spectrometric analysis yielded inhomogeneous and largely reciprocal distributions of Zn and Cu in the selected areas of
investigated brain samples. The highest concentrations of Zn and Cu with the most distinct distribution pattern were
found in the hippocampus (up to 15 mu g g(-1)). In contrast to zinc and copper, for lead, a more homogeneous
distribution throughout all regions examined was found at a low concentration (in the ng g(-1) range) level within the
analytical range of LA-ICP-MS. (c) 2007 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 18 of 23
Author(s): Balter, V (Balter, Vincent); Reynard, B (Reynard, Bruno)
Title: Secondary ionization mass spectrometry imaging of dilute stable strontium labeling in dentin and enamel
Source: BONE, 42 (1): 229-234 JAN 2008
Abstract:
The labeling of the zones of active mineralization in bone and tooth is usually achieved with calcium-binding
fluorescent dyes. However, these compounds are labile and mostly lost during the maturation process of the growing
tissue. Here we labeled mouse teeth using injections of dilute strontium (SrCl2, 500 mu g/ml), a trace element that is
naturally incorporated in hydroxyapatite, and resolve the subtle induced compositional changes using secondary ion
mass spectrometry (SIMS) imaging and analysis. Entire hemi-mandibules sampled at 14 and 28 days after birth are
embedded in resin and polished along longitudinal sections. SIMS chemical imaging reveals the double Sr labeling both
in dentin and enamel of molar teeth as two stripes with excess Sr concentration parallel to the dentino-enamel junction.
In order to quantify the variations of the strontium/calcium ratio (Sr/Ca), two international standards were sintered and
measured along with the samples. The concentration of Sr in the two stripes is about 300 mu g/g, which corresponds to
an enrichment factor of about 1.3-1.4 relative to the natural baseline. These results show that SIMS provides rapid and
quantitative imaging of small abundances of stable isotopes in growing mineralized tissues with a sensibility that is at
least two orders of magnitude higher than classical X-rays microanalysis. (C) 2007 Elsevier Inc. All rights reserved.
-------------------------------------------------------------------------------Record 19 of 23
Author(s): Andersson, M (Andersson, Malin); Groseclose, MR (Groseclose, M. Reid); Deutch, AY (Deutch, Ariel Y.);
Caprioli, RM (Caprioli, Richard M.)
Title: Imaging mass spectrometry of proteins and peptides: 3D volume reconstruction
Source: NATURE METHODS, 5 (1): 101-108 JAN 2008
Abstract:
As large genomic and proteomic datasets are generated from homogenates of various tissues, the need for information
on the spatial localization of their encoded products has become more pressing. Matrix-assisted laser desorptionionization (MALDI) imaging mass spectrometry (IMS) offers investigators the means with which to unambiguously
study peptides and proteins with molecular specificity, and to determine their distribution in two and three
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dimensions(1,2). In the past few years, several parameters have been optimized for IMS, including sample preparation,
matrix application and instrumental acquisition parameters(3,4) (Box 1). These developments have resulted in a high
degree of reproducibility in mass accuracy and peak intensities (Supplementary Fig. 1 online). Recently, we have
optimized our protocol to be able to increase the number of molecular species analyzed by collecting two sets of
sections, covering one set of sections with sinapinic acid for optimal detection of proteins and adjacent sections with
2,5-dihydroxybenzoic acid (DHB) matrix for the optimal detection of low-mass species, including peptides.
Approximately 1,000 peaks can be observed in each dataset (Fig. 1). Furthermore, the sections are collected at an equal
distance, 200 mu m instead of 400-500 mu m used previously, thus enabling the use of virtual z-stacks and threedimensional (3D) volume renderings to investigate differential localization patterns in much smaller brain structures
such as the substantia nigra and the interpeduncular nucleus. Here we present our optimized step-by-step procedure
based on previous work in our laboratory(2), describing how to make 3D volume reconstructions of MALDI IMS data,
as applied to the rat brain.
-------------------------------------------------------------------------------Record 20 of 23
Author(s): Tahallah, N (Tahallah, Nora); Brunelle, A (Brunelle, Alain); De La Porte, S (De La Porte, Sabine); Laprevote,
O (Laprevote, Olivier)
Title: Lipid mapping in human dystrophic muscle by cluster-time-of-flight secondary ion mass spectrometry imaging
Source: JOURNAL OF LIPID RESEARCH, 49 (2): 438-454 FEB 2008
Abstract:
Human striated muscle samples, from male control and Duchenne muscular dystrophy-affected children, were subjected
to cluster-time-of-flight secondary ion mass spectrometry (cluster-ToF-SIMS) imaging using a 25 keV Bi-3(+) liquid
metal ion gun under static SIMS conditions. Spectra and ion density maps, or secondary ion images, were acquired in
both positive and negative ion mode over several areas of 500 x 500 mu m(2) (image resolution, 256 x 256 pixels).
Characteristic distributions of various lipids were observed. Vitamin E and phosphatidylinositols were found to
concentrate within the cells, whereas intact phosphocholines accumulated over the most damaged areas of the
dystrophic muscles, together with cholesterol and sphingomyelin species. Fatty acyl chain composition varied
depending on the region, allowing estimation of the local damage extent.
-------------------------------------------------------------------------------Record 21 of 23
Author(s): Li, Y (Li, Yue); Shrestha, B (Shrestha, Bindesh); Vertes, A (Vertes, Akos)
Title: Atmospheric pressure infrared MALDI imaging mass spectrometry for plant metabolomics
Source: ANALYTICAL CHEMISTRY, 80 (2): 407-420 JAN 15 2008
Abstract:
The utility of atmospheric pressure infrared MALDI mass spectrometry (AP IR-MALDI) was assessed for plant
metabolomics studies. Tissue sections from plant organs, including flowers, ovaries, aggregate fruits, fruits, leaves,
tubers, bulbs, and seeds were studied in both positive and negative ion modes. For leaves, single laser pulses sampled
the cuticle and upper epidermal cells, whereas multiple pulses were demonstrated to ablate some mesophyll layers.
Tandem mass spectra were obtained with collision-activated dissociation to aid with the identification of some observed
ions. In the positive mode, most ions were produced as potassium, proton, or sometimes sodium ion adducts, whereas
proton loss was dominant in the negative ion mode. Over 50 small metabolites and various lipids were detected in the
spectra including, for example, 7 of the 10 intermediates in the citric acid cycle. Key components of the glycolysis
pathway occurring in the plant cytosol were found along with intermediates of phospholipid biosynthesis and reactants
or products of amino acid, nucleotide, oligosaccharide, and flavonoid biosynthesis. AP IR-MALDI mass spectrometry
was used to follow the fluid transport driven by transpiration and image the spatial distributions of several metabolites
in a white lily (Lilium candidum) flower petal.
-------------------------------------------------------------------------------Record 22 of 23
Author(s): Taatjes, CA (Taatjes, Craig A.); Hansen, N (Hansen, Nils); Osborn, DL (Osborn, David L.); KohseHoinghaus, K (Kohse-Hoeinghaus, Katharina); Cool, TA (Cool, Terrill A.); Westmoreland, PR (Westmoreland, Phillip
R.)
Title: "Imaging" combustion chemistry via multiplexed synchrotron-photoionization mass spectrometry
Source: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 10 (1): 20-34 2008
Abstract:
The combination of multiplexed mass spectrometry with photoionization by tunable-synchrotron radiation has proved to
be a powerful tool to investigate elementary reaction kinetics and the chemistry of low-pressure flames. In both of these
applications, multiple-mass detection and the ease of tunability of synchrotron radiation make it possible to acquire full
sets of data as a function of mass, photon energy, and of the physical dimension of the system, e. g. distance from the
burner or time after reaction initiation. The data are in essence an indirect image of the chemistry. The data can be
quantitatively correlated and integrated along any of several dimensions to compare to traditional measurements such as
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time or distance profiles of individual chemical species, but it can also be directly interpreted in image form. This
perspective offers an overview of flame chemistry and chemical kinetics measurements that combine tunable
photoionization with multiple-mass detection, emphasizing the overall insight that can be gained from multidimensional
data on these systems. The low-pressure flame apparatus is capable of providing isomer-resolved mass spectra of stable
and radical species as a function of position in the flame. The overall chemical structure of the flames can be readily
seen from images of the evolving mass spectrum as distance from the burner increases, with isomer-specific information
given in images of the photoionization efficiency. Several flames are compared in this manner, with a focus on
identification of global differences in fuel-decomposition and soot-formation pathways. Differences in the chemistry of
flames of isomeric fuels can be discerned. The application of multiplexed synchrotron photoionization to elementary
reaction kinetics permits identification of time-resolved isomeric composition in reacting systems. The power of this
technique is illustrated by the separation of direct and dissociative ionization signals in the reaction of C2H5 with O-2;
by the resolution of isomeric products in reactions of the ethynyl ( C2H) radical; and by preliminary observation of
branching to methyl + propargyl products in the self-reaction of vinyl radicals. Finally, prospects for future research
using multiplexed photoionization mass spectrometry are explored.
-------------------------------------------------------------------------------Record 23 of 23
Author(s): Chandra, S (Chandra, S.); Tjarks, W (Tjarks, W.); Lorey, DR (Lorey, D. R., II); Barth, RF (Barth, R. F.)
Title: Quantitative subcellular imaging of boron compounds in individual mitotic and interphase human glioblastoma
cells with imaging secondary ion mass spectrometry (SIMS)
Source: JOURNAL OF MICROSCOPY-OXFORD, 229 (1): 92-103 JAN 2008
Abstract:
Boron measurements at subcellular scale are essential in boron neutron capture therapy (BNCT) of cancer as the nuclear
localization of boron-10 atoms can enhance the effectiveness of killing individual tumour cells. Since tumours contain a
heterogeneous population of cells in interphase as well as in the M phase (mitotic division) of the cell cycle, it is
important to evaluate the subcellular distribution of boron in both phases. In this work, the secondary ion mass
spectrometry (SIMS) based imaging technique of ion microscopy was used to quantitatively image boron from two
BNCT agents, wclinically used p-boronophenylalanine (BPA) and 3-[4-(o-carboran-1-yl) butyl] thymidine (N4), in
mitotic metaphase and interphase human glioblastoma T98G cells. N4 belongs to a class of experimental BNCT agents,
designated 3- carboranyl thymidine analogues (3CTAs), which presumably accumulate selectively in cancer cells due to
a process referred to as kinase-mediated trapping (KMT). The cells were exposed to BPA for 1 h and N4 for 2 h. A
CAMECA IMS-3f SIMS ion microscope instrument capable of producing isotopic images with 500 nm spatial
resolution was used in the study. Observations were made in cryogenically prepared fast frozen, and freeze-fractured,
freeze-dried cells. Three discernible subcellular regions were studied: the nucleus, a characteristic mitochondria-rich
perinuclear cytoplasmic region, and the remaining cytoplasm in interphase T98G cells. In metaphase cells, the
chromosomes and the cytoplasm were studied for boron localization. Intracellular concentrations of potassium and
sodium also were measured in each cell in which the subcellular boron concentrations were imaged. Since the healthy
cells maintain a K/Na ratio of approximately 10 due to the presence of Na-K-ATPase in the plasma membrane of
mammalian cells, these measurements provided validation for cryogenic sample preparation and indicated the analysis
healthy, well preserved cells. The BPA-treated interphase cells revealed significantly lower concentrations of boron in
the perinuclear mitochondria-rich cytoplasmic region as compared to the remaining cytoplasm and the nucleus, which
were not significantly different from each other. In contrast, the BPA-treated metaphase cells revealed significantly
lower concentration of boron in their chromosomes than cytoplasm. In addition, the cytoplasm of metaphase cells
contained significantly less boron than the cytoplasm of interphase cells. These observations provide valuable
information on the reduced uptake of boron from BPA in mitotic cells for BPA-mediated BNCT. SIMS observations on
N4 revealed that boron was distributed throughout the interphase and mitotic cells, including the chromosomes. The
presence of boron in chromosomes of metaphase cells treated with N4 is indicative of a possible incorporation of this
thymidine analogue into DNA. The 3-DSIMS imaging approach for the analysis of mitotic cells shown in this work
should be equally feasible to the evaluation of other BNCT agents
Tracking of The Moving Target
Record 1 of 14
Author(s): Zelinsky, GJ (Zelinsky, Gregory J.); Neider, MB (Neider, Mark B.)
Title: An eye movement analysis of multiple object tracking in a realistic environment
Source: VISUAL COGNITION, 16 (5): 553-566 2008
Abstract:
To study multiple object tracking under naturalistic conditions, observers tracked 1-4 sharks (9 in total) swimming
throughout an underwater scene. Accuracy was high in the Track 1-3 conditions (> 92%), but declined when tracking 4
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targets (78%). Gaze analyses revealed a dependency between tracking strategy and target number. Observers tracking 2
targets kept their gaze on the target centroid rather than individual objects; observers tracking 4 targets switched their
gaze back-and-forth between sharks. Using an oculomotor method for identifying targets lost during tracking, we
confirmed that this strategy shift was real and not an artifact of centroid definition. Moreover, we found that tracking
errors increased with gaze time on targets, and decreased with time spent looking at the centroid. Depending on tracking
load, both centroid and target-switching strategies are used, with accuracy improving with reliance on centroid tracking.
An index juggling hypothesis is advanced to explain the suboptimal tendency to fixate tracked objects.
-------------------------------------------------------------------------------Record 2 of 14
Author(s): Kaartvedt, S (Kaartvedt, Stein); Torgersen, T (Torgersen, Thomas); Klevjer, TA (Klevjer, Thor A.); Rostad,
A (Rostad, Anders); Devine, JA (Devine, Jennifer A.)
Title: Behavior of individual mesopelagic fish in acoustic scattering layers of Norwegian fjords
Source: MARINE ECOLOGY-PROGRESS SERIES, 360: 201-209 2008
Abstract:
Mesopelagic acoustic scattering layers (SLs) in 2 fjords were studied from a stationary research vessel. Diel vertical
movements of SLs were assessed by hull-mounted transducers, while in situ behavior of individuals constituting the SLs
was resolved by a submerged echo sounder. The study focused on SLs made up of the lightfish Maurolicus muelleri and
the lanternfish Benthosema glaciale. Individual fish migrated in a pronounced stepwise manner, alternating between
vertical movements and stationary phases both during ascent and descent. Mean lengths of steps varied between 2.01
and 0.40 m, and mean duration of stationary phases between 69 and 36 s for fish in different SLs. Such travel-pause
behavior concords with saltatory search, where fish scan the water for prey during the stationary phases, relocate and
scan a new water parcel. Little activity was recorded among individuals in deep water, apart from infrequent, short shifts
in vertical distribution. This study shows that stationary submerged echo sounders can provide detailed information on
in situ behavior of mesopelagic fish.
-------------------------------------------------------------------------------Record 3 of 14
Author(s): Rawat, TK (Rawat, T. K.); Parthasarathy, H (Parthasarathy, H.)
Title: Manoeuvring target tracking with coordinated-turn motion using stochastic non-linear filter
Source: INTERNATIONAL JOURNAL OF CONTROL, 81 (7): 1102-1113 2008
Abstract:
Allowing for perturbations in speed and turn rate of a target moving in a coordinated turn obeys a non-linear stochastic
differential equation. Existing algorithms for coordinated turn tracking avoid this problem by ignoring perturbations in
the continuous time model and adding process noise only after discretisation. The dynamic model used here adds small
perturbations, modelled as independent Brownian motion processes, to the speed and turn rate. The target state is to be
recursively estimated from noisy discrete-time measurements of the target's range and bearing. In particular, this paper
examines the effect of the perturbations in speed and turn rate on the coordinated turn motion of the aircraft, and
subsequently the stochastic algorithm is developed by deriving the evolutions of conditional means and variances for
estimating the state of the aircraft. By linearizing the stochastic differential equations about the mean of the state vector
using first-order approximation, the mean trajectory of the resulting first-order approximated stochastic differential
model does not preserve the perturbation effect felt by the moving target; only the variance trajectory includes the
perturbation effect. For this reason, the effectiveness of the perturbed model is examined on the basis of the secondorder approximations of the system non-linearity. The theory of the non-linear filter of this paper is developed using the
Kolmogorov forward equation 'between the observation' and a functional difference equation for the conditional
probability density 'at the observation'. The effectiveness of the second-order non-linear filter is examined on the basis
of its ability to preserve perturbation effect felt by the aircraft. The Kolmogorov forward equation, however, is not
appropriate for numerical simulations, since it is the equation for the evolution of the conditional probability density.
Instead of the Kolmogorov equation, one derives the evolutions for the moments of the state vector, which in our case
consists of positions, velocities and turn rate of the manoeuvring aircraft. Even these equations are not appropriate for
the numerical simulations, since they are not closed in the sense that computing the evolution of a given moment
involves the knowledge of higher-order moments. Hence we consider the approximations to these moment evolution
equations. Simulation results are introduced to demonstrate the usefulness of an analytic theory developed in this paper.
-------------------------------------------------------------------------------Record 4 of 14
Author(s): Oksama, L (Oksama, Lauri); Hyona, J (Hyoenae, Jukka)
Title: Dynamic binding of identity and location information: A serial model of multiple identity tracking
Source: COGNITIVE PSYCHOLOGY, 56 (4): 237-283 JUN 2008
Abstract:
Tracking of multiple moving objects is commonly assumed to be carried out by a fixed-capacity parallel mechanism.
The present study proposes a serial model (MOMIT) to explain performance accuracy in the maintenance of multiple
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moving objects with distinct identities. A serial refresh mechanism is postulated, which makes recourse to continuous
attention switching, a capacity-limited episodic buffer for identity-location bindings, indexed location information
stored in the visuospatial short-term memory, and an active role of long-term memory. As identity-location bindings are
refreshed serially, a location error is inherent for all other targets except the focally attended one. The magnitude of this
location error is a key factor in predicting tracking accuracy. MOMIT's predictions were supported by the data of five
experiments: performance accuracy decreased as a function of target set-size, speed, and familiarity. A mathematical
version of MOMIT fitted nicely to the observed data with plausible parameter estimates for the binding capacity and
refresh time. (C) 2007 Elsevier Inc. All rights reserved.
-------------------------------------------------------------------------------Record 5 of 14
Author(s): Kemper, S (Kemper, Susan); McDowd, J (McDowd, Joan); Metcalf, K (Metcalf, Kim); Liu, CJ (Liu,
Chiung-Ju)
Title: Young and older adults' reading of distracters
Source: EDUCATIONAL GERONTOLOGY, 34 (6): 489-502 JUN 2008
Abstract:
Eye-tracking technology was employed to examine young and older adults' performance in the reading with distraction
paradigm. Distracters of 1, 2, and 4 words that formed meaningful phrases were used. There were marked age
differences in fixation patterns. Young adults' fixations to the distracters and targets increased with distracter length.
This suggests that they were attempting to integrate the distracters with the sentence and had more and more difficulty
doing so as the distracters increased in length. Young adults did have better comprehension of the sentences than older
adults, and they also had better recognition memory for target words and distracters.
-------------------------------------------------------------------------------Record 6 of 14
Author(s): Alvarez, TL (Alvarez, Tara L.); Beck, KD (Beck, Kevin D.); Ciuffreda, KJ (Ciuffreda, Kenneth J.); Chua,
FB (Chua, Florence B.); Daftari, A (Daftari, Anuj); DeMarco, RM (DeMarco, Robert M.); Bergen, MT (Bergen,
Michael T.); Servatius, RJ (Servatius, Richard J.)
Title: Brief intermittent light stimulation disrupts saccadic oculomotor control
Source: OPHTHALMIC AND PHYSIOLOGICAL OPTICS, 28 (4): 354-364 JUL 2008
Abstract:
Purpose: This study sought to determine the effect of very brief, single and multiple pulses of light on spatial and
temporal aspects of saccadic eye movements.
Methods: Twelve visually normal, young adult subjects participated in the experiments. Horizontal eye position was
monitored as subjects attempted to track target step displacements in the presence of either single or multiple brief
flashes of light in the visual field.
Results: Three primary findings were observed: (1) increased saccadic latency, (2) increased time for target acquisition
and (3) increased initial saccadic error.
Conclusion: The present findings suggest the influence of attentional processes and/or visual masking effects on
saccadic eye movement control.
-------------------------------------------------------------------------------Record 7 of 14
Author(s): Haddad, JM (Haddad, Jeffrey M.); Kloos, H (Kloos, Heidi); Keen, R (Keen, Rachel)
Title: Conflicting cues in a dynamic search task are reflected in children's eye movements and search errors
Source: DEVELOPMENTAL SCIENCE, 11 (4): 504-515 JUL 2008
Abstract:
Three-year-olds were given a search task with conflicting cues about the target's location. A ball rolled behind a
transparent screen and stopped behind one of four opaque doors mounted into the screen. A wall that protruded above
one door provided a visible cue of blockage in the ball's path, while the transparent screen allowed visual tracking of the
ball's progress to its last disappearance. On some trials these cues agreed and on others they conflicted. One group saw
the ball appear to pass through the wall, violating its solidity, and another group saw the ball stop early, behind a door
before the visual wall. Children's eye movements were recorded with an Applied Science Laboratories eye tracker
during these real object events. On congruent trials, children tended to track the ball to the visible barrier and select that
door. During conflict trials, children's eye movements and reaching errors reflected the type of conflict they experienced.
Our data support Scholl and Leslie's (1999) hypotheses that spatio-temporal and contact mechanical knowledge are
based on two separate, distinct mechanisms.
-------------------------------------------------------------------------------Record 8 of 14
Author(s): Song, R (Song, Rong); Tong, KY (Tong, Kai Yu); Hu, XL (Hu, Xiao Ling)
Title: Evaluation of velocity-dependent performance of the spastic elbow during voluntary movements
Source: ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION, 89 (6): 1140-1145 JUN 2008
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Abstract:
Objective: To evaluate quantitatively, using a voluntary elbow-tracking experiment, the performance at different angular
velocities of unaffected elbow compared with spastic elbow after stroke.
Design: Poststroke subjects were recruited to perform voluntary movements of elbow flexion and extension by
following sinusoidal trajectories from 30 degrees to 90 degrees at peak angular velocities of 15.7 degrees, 31.4 degrees,
47.1 degrees, 62.8 degrees, 78.5 degrees, and 94.2 degrees/s in a horizontal plane. The actual elbow angle and the target
position were displayed as real-time visual feedback.
Setting: Rehabilitation center research laboratory.
Participants: Nine hemiplegic chronic stroke patients.
Interventions: Not applicable.
Main Outcome Measures: Root mean square error (RMSE) between actual elbow angle and target angle, root mean
square jerk (RMSJ), and Modified Ashworth Scale (MAS). Jerk is the rate of change of acceleration, which is the third
derivative of the actual angle. A smooth motion has less jerk.
Results: The RMSE and RMSJ had a good reliability. The RMSE and RMSJ increased in both affected and unaffected
arms with increasing tracking velocity. The RMSE and RMSJ of the unaffected arms were significantly lower than
those of the affected arms at all the velocities. There was significant correlation between the RMSJ and MAS at the peak
velocities of 15.7 degrees, 31.4 degrees, 47.1 degrees, 62.8 degrees, and 94.2 degrees/s (correlation coefficient
range, .67-.83).
Conclusions: The parameters reflected motion quality, which has potential for use in quantitatively evaluating the
deficiencies of sensorimotor control of spastic elbow in persons after stroke during voluntary movements.
-------------------------------------------------------------------------------Record 9 of 14
Author(s): Collins, LM (Collins, Lisa M.)
Title: Non-intrusive tracking of commercial broiler chickens in situ at different stocking densities
Source: APPLIED ANIMAL BEHAVIOUR SCIENCE, 112 (1-2): 94-105 JUL 2008
Abstract:
Unlike several other farm animal species, the broiler chicken remains unprotected by species-specific legislation. The
densities at which broilers should be kept is a highly contentious issue-some studies have demonstrated increased
welfare problems at higher densities, whilst a few others have, contrary to expectations, suggested that broilers may
actually find crowds of other birds attractive. A tracking method was developed and used to provide an insight into the
social preferences of commercial broiler chickens in situ-inside commercial, closed-system broiler houses. The aim was
to simultaneously assess the relative impact of global measures of density, such as target and actual stocking densities
and local measures of the social environment on the behaviour and route taken to feed by focal birds. Birds were tracked
inside 20 commercial broiler houses across the UK. Results from this study show that stocking density per se seems to
have little direct effect on the individual behaviours of focal broiler chickens. However, there may still be an indirect
effect of stocking density on broiler behaviour, mediated through the local social environment. (C) 2007 Elsevier B.V.
All rights reserved.
-------------------------------------------------------------------------------Record 10 of 14
Author(s): Han, BS (Han, Bong Soo); Ahn, SH (Ahn, Sang Ho); Jang, SH (Jang, Sung Ho)
Title: Cortical reorganization demonstrated by diffusion tensor tractography analyzed using functional MRI activation
Source: NEUROREHABILITATION, 23 (2): 171-174 2008
Abstract:
The diffusion tensor tractography (DTT) allows the corticospinal tract(CST) to be visualized at the subcortical level and
functional MRI (fMRI) is capable of precisely identifying activation sites at the cortex. Therefore, it seems that
combined DTT/fMRI would allow more accurate evaluation of the state of the CST. We have attempted to demonstrate
cortical reorganization in a patient with cortical hemorrhage using DTT analyzed by fMRI activations. Six normal
subjects and a 12-year-old female patient with a hemorrhage in the left fronto-parietal cortex were recruited. fMRI was
performed at 1.5-T with timed hand grasp-release movements, and DTT was performed using 1.5-T with a Synergy-L
Sensitivity Encoding head coil. Three-dimensional reconstructions of the fiber tracts were obtained using the fMRI
activation as the seed region of interest and the CST area of the anterior pons as the target region of interest. The tract of
the affected hemisphere originated from the lateral area of the injured precentral knob and descended along the known
corticospinal tract pathway. It seems that the motor function of the affected hand was reorganized into the lateral area of
the injured precentral knob. Therefore, these combined modalities would be helpful in elucidating the state of the CST.
-------------------------------------------------------------------------------Record 11 of 14
Author(s): Huysmans, MA (Huysmans, M. A.); Hoozemans, MJM (Hoozemans, M. J. M.); van der Beek, AJ (van der
Beek, A. J.); de Looze, MP (de Looze, M. P.); van Dieen, JH (van Dieen, J. H.)
Title: Fatigue effects on tracking performance and muscle activity
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Source: JOURNAL OF ELECTROMYOGRAPHY AND KINESIOLOGY, 18 (3): 410-419 JUN 2008
Abstract:
It has been suggested that fatigue affects proprioception and consequently movement accuracy, the effects of which may
be counteracted by increased muscle activity. To determine the effects of fatigue on tracking performance and muscle
activity in the M. extensor carpi radialis (ECR), 11 female participants performed a 2-min tracking task with a computer
mouse, before and immediately after a fatiguing wrist extension protocol. Tracking performance was significantly
affected by fatigue. Percentage time on target was significantly lower in the first half of the task after the fatigue
protocol, but was unaffected in the latter half of the task. Mean distance to target and the standard deviation of the
distance to target were both increased after the fatigue protocol. The changed performance was accompanied by higher
peak EMG amplitudes in the ECR, whereas the static and the median EMG levels were not affected. The results of this
study showed that subjects changed tracking performance when fatigued in order to meet the task instruction to stay on
target. Contrary to our expectations, this did not lead to an overall higher muscle activity, but to a selective increase in
peak muscle activity levels of the ECR. (C) 2006 Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 12 of 14
Author(s): Cardenas, L (Cardenas, Luis); Lovy-Wheeler, A (Lovy-Wheeler, Alenka); Kunkel, JG (Kunkel, Joseph G.);
Hepler, PK (Hepler, Peter K.)
Title: Pollen tube growth oscillations and intracellular calcium levels are reversibly modulated by actin polymerization
Source: PLANT PHYSIOLOGY, 146 (4): 1611-1621 APR 2008
Abstract:
Prevention of actin polymerization with low concentrations of latrunculin B (Lat-B; 2 nM) exerts a profound inhibitory
effect on pollen tube growth. Using flow-through chambers, we show that growth retardation starts after 10 min
treatment with 2 nM Lat-B, and by 15 to 20 min reaches a basal rate of 0.1 to 0.2 mu m/s, during which the pollen tube
exhibits relatively few oscillations. If treated for 30 min, complete stoppage of growth can occur. Studies on the
intracellular Ca2+ concentration indicate that the tip-focused gradient declines in parallel with the inhibition of growth.
Tubes exhibiting nonoscillating growth display a similarly reduced and nonoscillating Ca2+ gradient. Studies on the pH
gradient indicate that Lat-B eliminates the acidic domain at the extreme apex, and causes the alkaline band to move
more closely to the tip. Removing Lat-B and returning the cells to control medium reverses these effects. Phalloidin
staining of F-actin reveals that 2 nM Lat-B degrades the cortical fringe; it also disorganizes the microfilaments in the
shank causing the longitudinally oriented elements to be disposed in swirls. Cytoplasmic streaming continues under
these conditions, however the clear zone is obliterated with all organelles moving into and through the extreme apex of
the tube. We suggest that actin polymerization promotes pollen tube growth through extension of the cortical actin
fringe, which serves as a track to target cell wall vesicles to preferred exocytotic sites on the plasma membrane.
-------------------------------------------------------------------------------Record 13 of 14
Author(s): Li, HS (Li, Haisen S.); Chetty, IJ (Chetty, Indrin J.); Enke, CA (Enke, Charles A.); Foster, RD (Foster, Ryan
D.); Willoughby, TR (Willoughby, Twyla R.); Kupellian, PA (Kupellian, Patrick A.); Solberg, TD (Solberg, Timothy D.)
Title: Dosimetric consequences of intrafraction prostate motion
Source: INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS, 71 (3): 801-812 JUL 1
2008
Abstract:
Purpose: To analyze characteristics of intrafraction prostate motion, monitored using the Calypso system, and
investigate dosimetric consequences of the motion for different clinical target volume (CTV) to planning target volume
(PTV) margins.
Methods and Materials: Motion characteristics were analyzed for 1,267 tracking sessions and 35 patients. Using
prostate-PTV margins of 0, 1, 2, 3, and 5 mm, dose metrics for the prostate gland, bladder, and rectum were evaluated
for scenarios including patient population, individual patients showing the greatest motion during the course of
treatment, and the individual session with the largest overall movement. Composite dose distributions incorporating
motion blurring were calculated by convolving static intensity-modulated radiotherapy plans with corresponding motion
probability functions.
Results: For prostate-PTV margins of 2 mm or greater, intrafraction motion did not compromise prostate dose coverage
for either the patient population or individual patients. For the patient showing the largest overall movement, the
prostate equivalent uniform dose was reduced by only 17.4 cGy (0.23%), and the minimum prostate dose remained
greater than 95% of the nominal dose. For margins less than 2 mm, the prostate dose-volume histogram in the same
patient was slightly compromised, and the equivalent uniform dose was reduced by 38.5 cGy (0.51%). Sparing of the
bladder and rectum was improved substantially by reducing margins.
Conclusions: Although significant motion can be observed during individual fractions, the closimetric consequences are
insignificant during a typical course of radiotherapy (30-40 fractions) with CTV-PTV margins of 2 mm or greater
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provided that the Calypso system is applied for pretreatment localization. Further reduction of the margin is possible if
intrafraction realignment is performed. (D 2008 Elsevier Inc.
-------------------------------------------------------------------------------Record 14 of 14
Author(s): Goss, M (Goss, Michael); Richards, C (Richards, Charlene)
Title: Development of a risk-based index for source water protection planning, which supports the reduction of
pathogens from agricultural activity entering water resources
Source: JOURNAL OF ENVIRONMENTAL MANAGEMENT, 87 (4): 623-632 JUN 2008
Abstract:
Source water protection planning (SWPP) is an approach to prevent contamination of ground and surface water in
watersheds where these resources may be abstracted for drinking or used for recreation. For SWPP the hazards within a
watershed that could contribute to water contamination are identified together with the pathways that link them to the
water resource. In rural areas, farms are significant potential sources of pathogens. A risk-based index can be used to
support the assessment of the potential for contamination following guidelines on safety and operational efficacy of
processes and practices developed as beneficial approaches to agricultural land management. Evaluation of the health
risk for a target population requires knowledge of the strength of the hazard with respect to the pathogen load (mass x
concentration). Manure handling and on-site wastewater treatment systems form the most important hazards, and both
can comprise confined and unconfined source elements. There is also a need to understand the modification of pathogen
numbers (attenuation) together with characteristics of the established pathways (surface or subsurface), which allow the
movement of the contaminant species from a source to a receptor (water source). Many practices for manure
management have not been fully evaluated for their impact on pathogen survival-and transport in the environment. A
key component is the identification of potential pathways of contaminant transport. This requires the development of a
suitable digital elevation model of the watershed for surface movement and information on local groundwater aquifer
systems for subsurface flows. Both require detailed soils and geological information. The pathways to surface and
groundwater resources can then be identified. Details of land management, farm management practices (including
animal and manure management) and agronomic practices have to be obtained, possibly from questionnaires completed
by each producer within the watershed. To confirm that potential pathways are active requires some microbial source
tracking. One possibility is to identify the molecular types of Escherichia coli present in each hazard on a farm. An
essential part of any such index is the identification of mitigation strategies and practices that can reduce the magnitude
of the hazard or block open pathways. (C) 2007 Elsevier Ltd. All rights reserved.
Ultraviolet Imaging \Detection
Record 1 of 24
Author(s): Cha, S (Cha, Seungwon); Kim, HJ (Kim, Hyung Jin); Kim, NH (Kim, Nam-Hoon); Roh, Y (Roh, Yonghan)
Title: Characteristics of gold nanowires and UV spectral changes by interaction between gold nanoparticles and DNA
Source: PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, 40 (7): 2545-2550 MAY 2008
Abstract:
Deoxyribonucleic acid (DNA) is ideal building blocks for conducting nanowires (NWs). DNA can obtain highly ordered
electronic components for nanocircutitry and/or nanodevices because of its very flexible length controllability,
nanometer-size diameter of about 2 nm and self-assembling properties. In this work, we used the method, which is the
direct gold nanowires (AuNWs) formation by the electrostatic assembly of DNA with negative charges in phosphate
groups and oxidized aniline-capped gold nanoparticles (AN-AuNPs) with positive charges in the solution phase. We
investigated the assembly process between AN-AuNPs and DNA molecules by the change. of incubation time and
estimated the number of DNA molecules wrapping the AuNP surface by the size of AuNPs. Atomic force microscopy
(AFM) images showed the interaction rate of AuNPs along DNA by the change of incubation time. AuNP number
attached on the DNA molecules increased according to the increase of incubation time. Ultraviolet-visible (UV)
spectroscopy measurement confirmed the assembly of AN-AuNPs and DNA by observing the formation of a novel
absorption peak according to the absorption spectral change of AN-AuNPs and DNA. (C) 2007 Elsevier B.V. All rights
reserved.
-------------------------------------------------------------------------------Record 2 of 24
Author(s): Owen, TC (Owen, Terence C.)
Title: Thiol detection, derivatization and tagging at micromole to nanomole levels using propiolates
Source: BIOORGANIC CHEMISTRY, 36 (1-3): 156-160 FEB-JUN 2008
Abstract:
Thiols, simple and complex, including polypeptide and protein thiols, react rapidly and selectively with esters of
propiolic acid under very mild conditions (aqueous buffer, room temperature, pH 7) to give thioacrylates. These stable
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derivatives exhibit strong, characteristic ultraviolet spectra, maximal at 280-290 nm, molar absorbance ca 12,500. In a
single, simple experiment the thiol is detected, its amount is estimated, it is stabilized against oxidation and disulfide
scrambling, it is converted into a derivative amenable to isolation and structure elucidation procedures, and it is tagged
with recognizable ultraviolet and NMR characteristics generated de novo. The reagents are stable and inexpensive and
the procedures are quick, easy, sensitive and selective. (C) 2008 Elsevier Inc. All rights reserved.
-------------------------------------------------------------------------------Record 3 of 24
Author(s): Beelen, A (Beelen, A.); Omont, A (Omont, A.); Bavouzet, N (Bavouzet, N.); Kovacs, A (Kovacs, A.);
Lagache, G (Lagache, G.); De Breuck, C (De Breuck, C.); Weiss, A (Weiss, A.); Menten, KM (Menten, K. M.); Colbert,
JW (Colbert, J. W.); Dole, H (Dole, H.); Siringo, G (Siringo, G.); Kreysa, E (Kreysa, E.)
Title: Submillimeter observations of the J2142-4423 Ly alpha protocluster at z=2.38
Source: ASTRONOMY & ASTROPHYSICS, 485 (3): 645-655 JUL 2008
Abstract:
Aims. We present observations aimed at exploring both the nature of Ly alpha emitting nebulae ("Ly alpha blobs") at z
= 2.38 and the way they trace large scale structure (LSS), by exploring their proximity to "maximum starbursts" through
submillimeter emission. Our most important objectives are to make a census of associated submillimeter galaxies
(SMGs), check their properties, and look for a possible overdensity in the protocluster J2142-4426 at z = 2.38.
Methods. We used the newly commissioned Large APEX Bolometer Camera (LABoCa) on the Atacama Pathfinder
EXperiment (APEX) telescope, in its Science Verification phase, to carry out a deep 10' x 10' map at 870 mu m, and we
performed multiple checks of the quality of data processing and source extraction.
Results. Our map, the first published deep image, confirms the capabilities of APEX/LABoCa as the most efficient
current equipment for wide and deep submm mapping. Twenty-two sources were securely extracted with 870 mu m flux
densities in the range 3-21 mJy, rms noise similar to 0.8-2.4 mJy, and far-IR luminosities probably in the range similar
to 5-20 x 1012 L (circle dot). Only one of the four 50 kpc-extended Ly alpha blobs has a secure 870 mu m counterpart.
The 870 mu m source counts in the whole area are marginally higher than in the SHADES SCUBA survey, with a
possible over-density around this blob. The majority of the 3.6-24 mu m SEDs of the submillimeter sources indicate
they are starburst dominated, with redshifts mostly greater than or similar to 2. However, there is evidence of a high-z
AGN in similar to 30% of the sources.
-------------------------------------------------------------------------------Record 4 of 24
Author(s): Etangs, ALD (Etangs, A. Lecavelier des); Vidal-Madjar, A (Vidal-Madjar, A.); Desert, JM (Desert, J. -M.);
Sing, D (Sing, D.)
Title: Rayleigh scattering by H-2 in the extrasolar planet HD 209458b
Source: ASTRONOMY & ASTROPHYSICS, 485 (3): 865-869 JUL 2008
Abstract:
Transiting planets, such as HD 209458b, offer a unique opportunity to scrutinize the planetary atmospheric content.
Although molecular hydrogen is expected to be the main atmospheric constituent, H-2 remains uncovered because of
the lack of strong transition from near-ultraviolet to near-infrared. Here we analyse the absorption spectrum of HD
209458b obtained by Sing et al. (2008a, ApJ, submitted) which provides a measurement of the absorption depth in the
3000-6200 angstrom wavelength range. We show that the rise in absorption depth at short wavelengths can be
interpreted as Rayleigh scattering within the atmosphere of HD 209458b. Since Rayleigh scattering traces the entire
atmosphere, this detection enables a direct determination of the pressure-altitude relationship, which is required to
determine the absolute fraction of other elements such as sodium. At the zero altitude defined by the absorption depth of
1.453%, which corresponds to a planetary radius of 0.1205 times the stellar radius, we find a pressure of 33 +/- 5 mbar.
Using the variation of the Rayleigh scattering cross-section as a function of wavelength, we determine the temperature
to be 2200 +/- 260 K at 33 mbar pressure.
-------------------------------------------------------------------------------Record 5 of 24
Author(s): Sander, LC (Sander, L. C.); Putzbach, K (Putzbach, K.); Nelson, BC (Nelson, B. C.); Rimmer, CA (Rimmer,
C. A.); Bedner, M (Bedner, M.); Thomas, JB (Thomas, J. Brown); Porter, BJ (Porter, B. J.); Wood, LJ (Wood, L. J.);
Schantz, MM (Schantz, M. M.); Murphy, KE (Murphy, K. E.); Sharpless, KE (Sharpless, K. E.); Wise, SA (Wise, S. A.);
Yen, JH (Yen, J. H.); Siitonen, PH (Siitonen, P. H.); Evans, RL (Evans, R. L.); Pho, AN (Pho, A. Nguyen); Roman, MC
(Roman, M. C.); Betz, JM (Betz, J. M.)
Title: Certification of standard reference materials containing bitter orange
Source: ANALYTICAL AND BIOANALYTICAL CHEMISTRY, 391 (6): 2023-2034 JUL 2008
Abstract:
A suite of three dietary supplement standard reference materials (SRMs) containing bitter orange has been developed,
and the levels of five alkaloids and caffeine have been measured by multiple analytical methods. Synephrine,
octopamine, tyramine, N-methyltyramine, hordenine, total alkaloids, and caffeine were determined by as many as six
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analytical methods, with measurements performed at the National Institute of Standards and Technology and at two
collaborating laboratories. The methods offer substantial independence, with two types of extractions, two separation
methods, and four detection methods. Excellent agreement was obtained among the measurements, with data
reproducibility for most methods and analytes better than 5% relative standard deviation. The bitter-orange-containing
dietary supplement SRMs are intended primarily for use as measurement controls and for use in the development and
validation of analytical methods.
-------------------------------------------------------------------------------Record 6 of 24
Author(s): Pendela, M (Pendela, Murali); Dragovic, S (Dragovic, Sanja); Bockx, L (Bockx, Lien); Hoogmartens, J
(Hoogmartens, Jos); Van Schepdael, A (Van Schepdael, Ann); Adams, E (Adams, Erwin)
Title: Development of a liquid chromatographic method for the determination of related substances and assay of Dcycloserine
Source: JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS, 47 (4-5): 807-811 AUG 5 2008
Abstract:
D-cycloserine or D-4-amino-3-isoxazolidinone is an antibiotic produced by Streptomyces garyphalus and Streptomyces
orchidaceus. D-cycloserine is used in the second line treatment of tuberculosis and is often used in developing countries.
Therefore, expensive high-tech techniques are not recommended for analysis. Here, a liquid chromatography method
with ultraviolet detection (LC-UV) is described using a base deactivated column (Hypersil BDS column; 25 cm x 4.6
mm I.D.) kept at 45 degrees C. The gradient method uses mobile phases containing acetonitrile (ACN), 20 mM sodium
octane sulphonate (SOS), 0.2 M potassium dihydrogen phosphate buffer pH 2.8, water: A: (4:70:10:16 v/v/v/v) and 13:
(17:70:10:3 v/v/v/v). The method proved to be robust, linear, repeatable, sensitive, selective and easy to perform. For
the related substances test 50 mu l of a 0.5 mg/ml D-cycloserine solution is injected. For assay, a concentration of 0.1
mg/ml is proposed to avoid overloading of the detector. (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 7 of 24
Author(s): Stevens, MH (Stevens, Michael H.); Gattinger, RL (Gattinger, R. L.); Gumbel, J (Gumbel, J.); Llewellyn, EJ
(Llewellyn, E. J.); Degenstein, DA (Degenstein, D. A.); Khaplanov, M (Khaplanov, M.); Witt, G (Witt, G.)
Title: First UV satellite observations of mesospheric water vapor - art. no. D12304
Source: JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 113 (D12): 12304-12304 JUN 21 2008
Abstract:
[1] We report the first UV satellite observations of mesospheric water vapor. The measurements are of nonthermal OH
prompt emission between 300-330 nm produced directly from the photodissociation of water vapor by H Lyman-alpha.
This technique is most sensitive to water vapor concentrations between 70-90 km altitude. We present OH data from
two limb scanning experiments: the Middle Atmosphere High Resolution Spectrograph Investigation (MAHRSI) and
the Optical Spectrograph and Infra-Red Imager System (OSIRIS). Interpretation of the lower resolution (similar to 1 nm)
OSIRIS spectra requires the rotational emission rate factors for OH( 1,1) solar fluorescence between 313-318 nm, which
we present for the first time herein. Comparison of water vapor concentration profiles with the most coincident profiles
from the Halogen Occultation Experiment on the Upper Atmosphere Research Satellite shows agreement to within 30%
between 75-80 km for both MAHRSI and OSIRIS. We discuss the benefits of this promising new approach to
measuring upper mesospheric water vapor and the need for new laboratory measurements to improve the analysis.
-------------------------------------------------------------------------------Record 8 of 24
Author(s): Cachorro, VE (Cachorro, V. E.); Toledano, C (Toledano, C.); Berjon, A (Berjon, A.); de Frutos, AM (de
Frutos, A. M.); Torres, B (Torres, B.); Sorribas, M (Sorribas, M.); Laulainen, NS (Laulainen, N. S.)
Title: An "in situ" calibration correction procedure (KCICLO) based on AOD diurnal cycle: Application to AERONET El Arenosillo (Spain) AOD data series - art. no. D12205
Source: JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 113 (D12): 12205-12205 JUN 21 2008
Abstract:
[1] Aerosol optical depth (AOD) very often shows a distinct diurnal cycle pattern, which seems to be an artifact
resulting from an incorrect calibration ( or an equivalent effect, such as filter degradation). The shape of this fictitious
AOD diurnal cycle varies as the inverse of the solar air mass (m) and the magnitude of the effect is greatest at midday.
The observation of this effect is not easy at many field stations, and only those stations with good weather conditions
permit an easier detection and the possibility of its correction. By taking advantage of this dependence on the air mass,
we propose an improved "in situ'' correction-calibration procedure to AOD measured data series. The method is named
KCICLO because the determination of a constant K and the behavior of AOD as a cycle (ciclo, in Spanish). We estimate
it has an accuracy of 0.2-0.5% for the calibration ratio constant K, or 0.002-0.005 in AOD at field stations. Although the
KCICLO is an "in situ'' calibration method, we recommend it to be used as an AOD correction method for field stations.
At high-altitude sites, it may be used independently of the classical Langley method (CLM). However, we also
recommend it to be used as a complement to CLM, improving it considerably. The application of this calibration
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correction method to the nearly 5 year AOD data series at El Arenosillo (Huelva, southwestern Spain) station belonging
to Aerosol Robotic Network (AERONET)PHOTONS shows that 8 (50%) of 16 filters of the four analyzed Sun
photometers were outside of the 0.02 uncertainty of AERONET specification. The largest departures reached values of
0.06. The results show the efficiency of the method and a significant improvement over other "in situ'' methods, with no
other information required beyond the same AOD data.
-------------------------------------------------------------------------------Record 9 of 24
Author(s): Maillard, O (Maillard, Olivier); Camenisch, U (Camenisch, Ulrike); Blagoev, KB (Blagoev, Krastan B.);
Naegeli, H (Naegeli, Hanspeter)
Title: Versatile protection from mutagenic DNA lesions conferred by bipartite recognition in nucleotide excision repair
Source: MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH, 658 (3): 271-286 Sp. Iss. SI MAR-APR
2008
Abstract:
Nucleotide excision repair is a cut-and-patch pathway that eliminates potentially mutagenic DNA lesions caused by
ultraviolet light, electrophilic chemicals, oxygen radicals and many other genetic insults. Unlike antigen recognition by
the immune system, which employs billions of immunoglobulins and T-cell receptors, the nucleotide excision repair
complex relies on just a few generic factors to detect an extremely wide range of DNA adducts. This molecular
versatility is achieved by a bipartite strategy initiated by the detection of abnormal strand fluctuations, followed by the
localization of injured residues through an enzymatic scanning process coupled to DNA unwinding. The early
recognition subunits are able to probe the thermodynamic properties of nucleic acid substrates but avoid direct contacts
with chemically altered bases. Only downstream subunits of the bipartite recognition process interact more closely with
damaged bases to delineate the sites of DNA incision. Thus, consecutive factors expand the spectrum of deleterious
genetic lesions conveyed to DNA repair by detecting distinct molecular features of target substrates. (C) 2008 Elsevier
B.V. All rights reserved.
-------------------------------------------------------------------------------Record 10 of 24
Author(s): LeBlanc, WG (LeBlanc, William G.); Vidal, L (Vidal, Liat); Kirsner, RS (Kirsner, Robert S.); Lee, DJ (Lee,
David J.); Caban-Martinez, AJ (Caban-Martinez, Alberto J.); McCollister, KE (McCollister, Kathryn E.); Arheart, KL
(Arheart, Kristopher L.); Chung-Bridges, K (Chung-Bridges, Katherine); Christ, S (Christ, Sharon); Clark, J (Clark,
John, III); Lewis, JE (Lewis, John E.); Davila, EP (Davila, Evelyn P.); Rouhani, P (Rouhani, Panta); Fleming, LE
(Fleming, Lora E.)
Title: Reported skin cancer screening of US adult workers
Source: JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY, 59 (1): 55-63 JUL 2008
Abstract:
Background: Early detection of skin cancer by skin examination may reduce its associated morbidity and mortality, in
particlular for workers routinely exposed to sun.
Objectives: We sought to describe the proportion of US workers reporting skin cancer screening examination in a
representative sample of the US worker population in the National Health Interview Survey.
Methods: Report of skin cancer examination in the 2000 and 2005 National Health Interview Survey cancer control
supplements were examined by a range of variables.
Results: Lifetime and 12-month reported clinical skin examination prevalence was 15% and 8%, respectively. Workers
with elevated occupational exposure to ultraviolet light were less likely to have ever received a skin examination than
the average US worker. Logistic regression analysis identified occupational category and age, sex, race, education level,
health insurance, and sun-protective behavior as significant independent correlates of skin cancer examination.
Limitations: A limitation is potential healthy worker effect and underestimation of skin cancer screening with selfreported data.
Conclusions: Routine examination by primary care physicians frequently does not include a thorough skin examination.
Physicians should be even more vigilant with patients at increased risk of excessive occupational sun exposure, as early
detection of skin cancer by periodic skin examination decreases morbidity and can improve survival.
-------------------------------------------------------------------------------Record 11 of 24
Author(s): Dugo, P (Dugo, P.); Kumm, T (Kumm, T.); Cacciola, F (Cacciola, F.); Dugo, G (Dugo, G.); Mondello, L
(Mondello, L.)
Title: Multidimensional liquid chromatographic separations applied to the analysis of food samples
Source: JOURNAL OF LIQUID CHROMATOGRAPHY & RELATED TECHNOLOGIES, 31 (11-12): 1758-1807
2008
Abstract:
Nowadays, multidimensional techniques occupy an expanding niche in separation science, being strong evidence that
one-dimensional systems are by themselves inadequate, especially when challenged with highly complex samples. No
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exceptions are foodstuffs: analytical multidimensional methods not only allow the qualitative and quantitative
determination of the main compounds, but can also be selective and sensitive enough to permit the determination of
minor components. The present review gives an overview of the application of three main types of multidimensional
separations, off-line, on-line/heart-cutting, and comprehensive liquid chromatography, for the analysis of food and
beverages. The principles, advantages, and disadvantages of each approach are briefly described.
-------------------------------------------------------------------------------Record 12 of 24
Author(s): Carratu, B (Carratu, B.); Boniglia, C (Boniglia, C.); Giammarioli, S (Giammarioli, S.); Mosca, M (Mosca,
M.); Sanzini, E (Sanzini, E.)
Title: Free amino acids in botanicals and botanical preparations
Source: JOURNAL OF FOOD SCIENCE, 73 (5): C323-C328 JUN-JUL 2008
Abstract:
Numerous studies were carried out about aminoacidic composition of vegetable proteins, but information about the free
amino azid pool and the role of these substances is very Incomplete. The aim of this was to contribute to the scarce
knowledge concerning the composition of free amino acids in botanicals and botanical preparations widely used vs food,
in dietary supplements, and in pharmaceutical products. This work si the composition of free amino acids, Identified the
major components of 19 species of plants, and evaluated the influence of different types of extraction on the amino acid
profile. Amino acids were determined using an automatic precolumn derivatization with fluroenylmethyl-chloroformate
and reversed-phase liquid chromatography with fluorescence and ultraviolet detection. The amounts of total free amino
acids varied widely between plants, from approximately 12 g in 100 g of Echinacea pallida extract to less than 60 mg in
the same amount of Coleus forskohlii, Garcinia cambogia, and Glycine max. In 13 plants arginine, asparagine,
glutamine, proline, and gamma-aminobutyric acid were the free amino acids found in preponderant quantities. The
levels of free amino acids above the quantification limit in 36 assayed samples of botanicals, extracts, and supplements
are shown.
-------------------------------------------------------------------------------Record 13 of 24
Author(s): Van Hai, L (Van Hai, Le); Kanashima, T (Kanashima, Takeshi); Okuyama, M (Okuyama, Masanori)
Title: Enhancement of memory retention time of MFIS structure with SBT ferroelectric and SiO2 buffer layers treated
by nitrogen radical irradiation
Source: INTEGRATED FERROELECTRICS, 96: 27-39 2008
Abstract:
Nitrogen radical irradiation has been used to improve the retention memory characteristic of
Pt/SrBi2Ta2O9(SBT)/SiO2/n-Si metal-ferroelectric-insulator-semiconductor (MFIS) structures. It is demonstrated
leakage currents through buffer and ferroelectric layers have decreased due to improvements of electronic property by
the irradiation treatment. Furthermore, C-V characteristics also show wide memory window and steep slope in depletion
region corresponding to good interface layers and minimized diffusion between layers. Nitrogen incorporated in surface
layers of SiO2 and SBT has been confirmed by X-ray Photoelectron Spectroscopy(XPS). Ultraviolet Photoyield
Spectroscopy(UV-PYS) measurements show Fermi level energy and band gap of SBT surface layer are modified and
depend on radiation time. Surface morphology of SBT thin films with various treatment periods were investigated by
SEM and AFM images. The retention time of capacitor in ON and OFF states of MFIS structures is longer than 2 weeks.
-------------------------------------------------------------------------------Record 14 of 24
Author(s): Ra, S (Ra, Sejin); Kim, S (Kim, Sunghwan); Kim, HJ (Kim, H. J.); Park, H (Park, H.); Lee, S (Lee,
Sanghoon); Kang, H (Kang, Heedong); Doh, SH (Doh, Sih-Hong)
Title: Luminescence and scintillation properties of a CeBr3 single crystal
Source: IEEE TRANSACTIONS ON NUCLEAR SCIENCE, 55 (3): 1221-1224 Part 2 JUN 2008
Abstract:
Crystal growth, luminescence, and scintillation properties of a CeBr3 crystal are presented. The crystal was grown with
Bridgman method using two-zone transparent furnace and cut to phi 10 x 10 mm(3). The investigation of luminescence
and scintillation properties of the CeBr3 was performed under the excitation by ultraviolet and gamma-rays at room
temperature. The emission spectrum of the CeBr3 was observed in the range of near ultraviolet to violet, which is due to
5d --> 4f transition of the Ce3+. The decay time of the Ce3+ emission was measured to be approximately 20 ns. The
energy resolution of the CeBr3 single crystal was obtained to be 4.9% for the Cs-137 662 keV gamma-ray. The relative
signal of the CeBr3 crystal by the Cs-137 gamma -ray is about three times higher than that of a CsI:Tl crystal when bialkali PMT was used. The nonproportionality in the gamma-ray energy of the crystal was also measured. The study
showed that the CeBr3 crystal is the promising candidate for the PET application. The CeBr3 crystal with high light
output and fast decay time affords its use for the particle detection in high counting rate environment such as nuclear
and high-energy physics.
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Record 15 of 24
Author(s): Storrie-Lombardi, MC (Storrie-Lombardi, Michael C.); Muller, JP (Muller, J. -P.); Fisk, MR (Fisk, M. R.);
Griffiths, AD (Griffiths, A. D.); Coates, AJ (Coates, A. J.)
Title: Potential for non-destructive astrochemistry using the ExoMars PanCam - art. no. L12201
Source: GEOPHYSICAL RESEARCH LETTERS, 35 (12): 12201-12201 JUN 20 2008
Abstract:
We investigate the utility of adding a 365 nm ultraviolet (UV) light source to the ExoMars panoramic camera (PanCam)
scheduled for launch in 2013. The modification makes it feasible to monitor rover drill cuttings for aromatic organic
molecules and provide constraints on polycyclic aromatic hydrocarbons (PAH) as a function of depth to the 2-meter
limit of the ExoMars drill. This non-destructive triage allows prioritized deployment of organic detection experiments
requiring sample destruction and/or expenditure of non-replaceable resources. Utilizing the Beagle 2 PanCam backup
filter wheel fitted with original blue (440 nm), green ( 530 nm), and red ( 670 nm) filters we captured fluorescent images
following 365 nm excitation of 3-, 4- and 5-ring PAH species doped on Mars analog peridotite grains. We demonstrate a
detection limit for pyrene of 1.5 mu g in granular peridotite doped at pyrene levels of 50 +/- 5 ppm for camera-to-target
distance of 1 meter.
-------------------------------------------------------------------------------Record 16 of 24
Author(s): Fujikake, H (Fujikake, Hideo); Sato, H (Sato, Hiroto)
Title: Flexible display technologies using ferroelectric liquid crystal: Low driving-voltage panel fabrication
Source: FERROELECTRICS, 364: 86-94 2008
Abstract:
We have reduced driving voltage of a flexible ferroelectric liquid crystal panel with polymer fibers and walls fastening
two thin plastic substrates. The saturation voltage in the monostable V-shaped electrooptic property, was decreased at
several V, by dispersing fine sparse polymer fibers with small monomer concentration and by forming rigid polymer
walls with strong ultraviolet light irradiation. The formation process and mechanism of the polymers were considered in
detail. The rise and decay response times were measured, and the total response time was less than 1 ms. The
outstanding features were applicable to a flexible large-size moving-image display panel with a direct-illumination-type
bendable backlight sheet arraying small LED chips for field sequential color driving technique.
-------------------------------------------------------------------------------Record 17 of 24
Author(s): Ostman, L (Ostman, L.); Goobar, A (Goobar, A.); Mortsell, E (Mortsell, E.)
Title: Extinction properties of lensing galaxies
Source: ASTRONOMY & ASTROPHYSICS, 485 (2): 403-415 JUL 2008
Abstract:
Context. Observations of quasars shining through foreground galaxies, offer a way to probe the dust extinction curves of
distant galaxies. Interesting objects for this study are found in strong gravitational lensing systems, where the
foreground galaxies generate multiple images.
Aims. The reddening law of lensing galaxies is investigated by studying the colours of gravitationally-lensed quasars,
and a handful of other quasars where a foreground galaxy is detected.
Methods. We compare the observed colours of quasars reported in the literature, with spectral templates reddened by
different extinction laws and dust properties. The data consists of 21 quasar-galaxy systems, with a total of 48 images.
The galaxies, which are both early- and late-type, have redshifts in the interval z = 0.04-1.51.
Results. We measure a difference in rest-frame B - V between the quasar images we study, and quasars without resolved
foreground galaxies. This difference in colour is indicative of significant dust extinction in the intervening galaxy. Good
fits to standard extinction laws were found for 22 of the images, corresponding to 13 different galaxies. Our fits imply a
wide range of possible values for the total-to-selective extinction ratio, RV. The distribution was found to be broad with
a weighted mode of (R) over barV = 2.4 and a FWHM of Delta R-V = 2.7 (sigma(RV) similar to 1.1). Thus the bulk of
the galaxies for which good reddening fits could be derived, have dust properties compatible with the Milky Way value
(R-V = 3.1).
-------------------------------------------------------------------------------Record 18 of 24
Author(s): Wu, CX (Wu Chun-Xia); Zhou, M (Zhou Ming); Feng, CC (Feng Cheng-Cheng); Yuan, R (Yuan Run); Li,
G (Li Gang); Ma, WW (Ma Wei-Wei); Cai, L (Cai Lan)
Title: Study on ultraviolet emission mechanism of micro-nano multi-scale ZnO structures
Source: ACTA PHYSICA SINICA, 57 (6): 3887-3891 JUN 2008
Abstract:
The micro-nano multi-scale ZnO structure was synthesized by the vapor phase transport process onto Si ( 100) substrate.
A typical scanning electron microscope ( SEM) image of the sample clearly showed the surface has the complex
structure of hexagonal micro and nano- rods. Photoluminescence ( PL) spectra at room temperature showed an intense
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near-band-gap ultraviolet (UV) emission peak but no deep level emission related to impurities or defects, indicating that
the sample has good optical quality. The temperature (83-307 K) dependence of the PL spectra showed that the roomtemperature UV emission resulted from two optical transitions, one related to the ZnO free exciton and the other related
to the free-to-bound ( FB) transition of the free cawier with the binding energy of about 124.6 meV.
-------------------------------------------------------------------------------Record 19 of 24
Author(s): Wang, M (Wang, Min); Min, YL (Min, Yulin); Chen, YC (Chen, Youcun)
Title: Simple approach to NiS2/Ag2S composites and their optical properties
Source: MATERIALS LETTERS, 62 (17-18): 3280-3283 JUN 30 2008
Abstract:
NiS2/Ag2S composites have been successfully prepared through a simple approach by using nickel disulfide hollow
microspheres as precursors under normal temperature and pressure. The morphologies and microstructures of NiS2 and
NiS2/Ag2S composites were illustrated by SEM and TEM images. SEM images indicate the average diameter of the
silver sulfide nanospheres is 100 nm. And the NiS2/Ag2S composites display strong luminescent emission in ultraviolet
region. This approach provides a facile route for the synthesis of the NiS2/Ag2S composites with interesting optical
property. Furthermore, this simple method could be applied to synthesize other composites. (c) 2008 Elsevier B.V. All
rights reserved.
-------------------------------------------------------------------------------Record 20 of 24
Author(s): Moeggenborg, K (Moeggenborg, Kevin); Batllo, F (Batllo, Francois); McMullen, D (McMullen, Daniel);
Reggie, S (Reggie, Stan)
Title: Chemical-mechanical polishing shines mirrors
Source: LASER FOCUS WORLD, 44 (6): 90-93 JUN 2008
Abstract:
A new chemical-mechanical polishing technique extends the use of monolithic aluminium optics beyond the infrared
and into the visible and ultraviolet spectrum for imaging and beam-steering applications.
-------------------------------------------------------------------------------Record 21 of 24
Author(s): Kang, IY (Kang, In-Yong); Ahn, J (Ahn, Jinho); Chung, YC (Chung, Yong-Chae); Oh, HK (Oh, Hye-Keun)
Title: Aerial image characteristics of a modified absorber model for extreme ultraviolet lithography (EUVL)
Source: JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 52 (6): 1759-1762 JUN 2008
Abstract:
The aerial image characteristics of the modified absorber model with various sidewall angles were quantitatively
investigated by calculating the near field intensity on a mask and the aerial image intensity on a wafer. For the
calculation of the near field intensity and the aerial image intensity of a 25-nm isolated patterned mask, SOLID-EUV,
which is capable of a rigorous electromagnetic-field computation, was employed. The aerial image intensity of a
patterned mask with positive and negative sidewall angles was calculated and compared with the value of the vertical
sidewall model for various sidewall angle and illumination angle variations. Through the investigation of the aerial
image characteristics of various absorber models, the absorber model with a positive sidewall angle can be suggested as
the optimal absorber design to minimize the shadowing effect.
-------------------------------------------------------------------------------Record 22 of 24
Author(s): Reines, AE (Reines, Amy E.); Johnson, KE (Johnson, Kelsey E.); Goss, WM (Goss, W. M.)
Title: Emerging massive star clusters revealed: High-resolution imaging of NGC 4449 from the radio to the ultraviolet
Source: ASTRONOMICAL JOURNAL, 135 (6): 2222-2239 JUN 2008
Abstract:
We present a multi-wavelength study of embedded massive clusters in the nearby (3.9 Mpc) starburst galaxy NGC 4449
in an effort to uncover the earliest phases of massive cluster evolution. By combining high-resolution imaging from the
radio to the ultraviolet, we reveal these clusters to be in the process of emerging from their gaseous and dusty birth
cocoons. We use Very Large Array (VLA) observations at centimeter wavelengths to identify young clusters surrounded
by ultra-dense H II regions, detectable via their production of thermal free-free radio continuum. Ultraviolet, optical and
infrared observations are obtained from the Hubble and Spitzer Space Telescope archives for comparison. We detect 39
compact radio sources toward NGC 4449 at 3.6 cm using the highest resolution (1.'' 3) and sensitivity (similar to 12 mu
Jy) VLA image of the galaxy to date. We reliably identify 13 thermal radio sources and derive their physical properties
using both nebular emission from the H II regions and spectral energy distribution fitting to the stellar continuum. These
radio-detected clusters have ages less than or similar to 5 Myr and stellar masses of order 10(4) M-circle dot. The
measured extinctions are quite low: 12 of the 13 thermal radio sources have AV less than or similar to 1.5, while the
most obscured source has A(V) approximate to 4.3. By combining results from the nebular and stellar emission, we find
an I-band excess that is anti-correlated with cluster age and an apparent mass-age correlation. Additionally, we find
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evidence that local processes such as supernovae and stellar winds likely play an important role in triggering the current
bursts of star formation within NGC 4449.
-------------------------------------------------------------------------------Record 23 of 24
Author(s): Liu, KW (Liu, K. W.); Shen, DZ (Shen, D. Z.); Shan, CX (Shan, C. X.); Zhang, JY (Zhang, J. Y.); Jiang, DY
(Jiang, D. Y.); Zhao, YM (Zhao, Y. M.); Yao, B (Yao, B.); Zhao, DX (Zhao, D. X.)
Title: The growth of ZnMgO alloy films for deep ultraviolet detection - art. no. 125104
Source: JOURNAL OF PHYSICS D-APPLIED PHYSICS, 41 (12): 25104-25104 JUN 21 2008
Abstract:
ZnMgO films are prepared by RF magnetron sputtering using a composite target and the Mg composition of the samples
can be controlled easily even at a high growth temperature. The metal-semiconductor-metal photodetector based on the
wurtzite Zn0.6Mg0.4O film exhibits a very low dark current (5 pA at vertical bar V-bias vertical bar = 3V) and a high
UV/visible rejection ratio (more than three orders of magnitude). The peak responsivity of the photodetector is at around
270 nm and a very sharp cutoff wavelength is at a wavelength of about 295 nm corresponding to the absorption edge of
the Zn0.6Mg0.4O film.
-------------------------------------------------------------------------------Record 24 of 24
Author(s): Collison, MW (Collison, Mark W.)
Title: Determination of total soy isoflavones in dietary supplements, supplement ingredients, and soy foods by highperformance liquid chromatography with ultraviolet detection: Collaborative study
Source: JOURNAL OF AOAC INTERNATIONAL, 91 (3): 489-500 MAY-JUN 2008
Abstract:
An interlaboratory study was conducted to evaluate a method for determining total soy isoflavones in dietary
supplements, dietary supplement ingredients, and soy foods. lsoflavones were extracted using aqueous acetonitrile
containing a small amount of dimethylsulfoxide (DMSO) and all 12 of the naturally occuring isoflavones in soy were
determined by high-performance liquid chromatography (HPLC) with UV detection using apigenin as an internal
standard. Fifteen samples (6 pairs of blind duplicates plus 3 additional samples) of soy isoflavone ingredients, soy
isoflavone dietary supplements, soy flour, and soy protein products were successfully analyzed by 13 collaborating
laboratories in 6 countries. For repeatability, the relative standard deviations (RSDr) ranged from 1.07 for samples
containing over 400 mg/g total isoflavones to 3.31 for samples containing 0.87 mg/g total isoflavones, and for
reproducibility the RSDR values ranged from 2.29 for samples containing over 400 mg/g total isoflavones to 9.36 for
samples containing 0.87 mg/g total isoflavones. HorRat values ranged from 1.00 to 1.62 for all samples containing at
least 0.8 mg/g total isoflavones. One sample, containing very low total isoflavones (< 0.05 mg/g), gave RSDR values of
175 and a HorRat value of 17.6. This sample was deemed to be below the usable range of the method. The method
provides accurate and precise results for analysis of soy isoflavones in dietary supplements and soy foods.
Optical tweezers/ Photochromic
Record 1 of 13
Author(s): Naumov, P (Naumov, Pance); Yu, P (Yu, Pei); Sakurai, K (Sakurai, Kenji)
Title: Electronic tera-order stabilization of photoinduced metastable species: Structure of the photochromic product of
spiropyran determined with in situ single crystal X-ray photodiffraction
Source: JOURNAL OF PHYSICAL CHEMISTRY A, 112 (26): 5810-5814 JUL 3 2008
Abstract:
The extraordinary stability of the photoinduced red form of a cationic spiropyran (k approximate to 10(-6) s(-1) in water
and similar to 10(-6) to less than 10(-8) s(-1) in the solid state) was employed to obtain in situ X-ray diffraction
evidence of its molecular structure. By UV excitation under selected experimental conditions, on average,
approximately one third of the cations in a single crystal of spiropyran iodide salt was converted and retained as the red
form during the experiment. According to the structure of the mixed crystal, the ring opening, which is due to increased
distance between the spiro oxygen and carbon atoms, is associated with slight molecular flattening caused by concurrent
out-of-plane shift (11.2(5)degrees) of the pyranopyridinium half and in-plane shift (4.8(7)degrees) of the indoline half.
The overall geometry change of the cation fits the steric requirements imposed by the ion packing in the crystal and can
be viewed as molecular flattening caused by breaking of the spiroconjugation. The structure of the cation confirms that
(at least in the case of cationic spiropyrans) the product is confined in the crystal mainly as a zwitterionic resonance
structure in cis configuration similar to the (early) transition state. Although the positive charge of the closed form
facilitates the ring-opening reaction by moving the reactant closer to the transition state, neither the weakening of the
spiropyran C-O bond nor the space provided by the iodide alone can account for the stability of the product. Instead, the
density functional theory calculations indicate that the stabilization of the red form of the cationic relative to the neutral
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spiropyran is thermodynamically controlled, probably through compensation of the charge within the zwitterion by the
methylpyridinium group.
-------------------------------------------------------------------------------Record 2 of 13
Author(s): Yang, PC (Yang, Po-Chih); Wu, MZ (Wu, Ming-Zu); Liu, JH (Liu, Jui-Hsiang)
Title: Synthesis and characterization of liquid crystalline copolymers with dual photochromic pendant groups
Source: POLYMER, 49 (12): 2845-2856 JUN 10 2008
Abstract:
In order to study the photoreactivity and the optical properties of liquid crystalline copolymers with multiple
photochromic groups, a series of novel liquid crystalline binary and ternary polyacrylates consisting of one (C=C OF
N=N) or dual (C=C and N=N) photochromic segments were synthesized and characterized considering their liquid
crystalline, optical, and photochromic properties and their thermal stability. Achiral homopolymer PI shows a smectic A
phase (fan-shaped texture), and all chiral copolymers CP1-CP6 exhibit chiral nematic phases (cholesteric, oily streaks
textures). The polymers show excellent solubility in common organic solvents such as chloroform, toluene, and THE
These polymers also exhibit good thermal stability, with decomposition temperatures (TdS) greater than 373 degrees C
at 5% weight loss, and beyond 440 degrees C at 50% weight loss under nitrogen atmosphere. UV irradiation caused E/Z
photoisomerization at N=N and C=C segments of the synthesized photochromic copolymers leading to reversible and
irreversible isomerizations, respectively. The synthesized liquid crystalline ternary copolymer CP6, containing two
different photochromic N=N and C=C groups, is sensitive to different UV wavelengths and is notably interesting from
the viewpoint of photochromic copolymers. (C) 2008 Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 3 of 13
Author(s): Whelan, J (Whelan, Jamie); Wojtyk, JTC (Wojtyk, James T. C.); Buncel, E (Buncel, Erwin)
Title: Enhanced bistability of a photochromic microparticle in condensed medium
Source: CHEMISTRY OF MATERIALS, 20 (12): 3797-3799 JUN 24 2008
-------------------------------------------------------------------------------Record 4 of 13
Author(s): Finden, J (Finden, Jeremy); Kunz, TK (Kunz, Tamara K.); Branda, NR (Branda, Neil R.); Wolf, MO (Wolf,
Michael O.)
Title: Reversible and amplified fluorescence quenching of a photochromic polythiophene
Source: ADVANCED MATERIALS, 20 (10): 1998-+ MAY 19 2008
Abstract:
Amplification of fluorescence quenching of a polythiophene is optically triggered by converting pendant dithienylethene
(DTE) photoswitches to their ring-closed isomers using UV light. The effect can be reversed with visible light, which
regenerates the original DTE isomer. Amplification attributed to the high mobility of electronic excited states in
conjugated polymers, which facilitates energy transfer to a ring-closed DTE.
-------------------------------------------------------------------------------Record 5 of 13
Author(s): Yamaguchi, T (Yamaguchi, Tadatsugu); Uchida, K (Uchida, Kingo); Irie, M (Irie, Masahiro)
Title: Photochromic properties of diarylethene derivatives having benzofuran and benzothiophene rings based on
regioisomers
Source: BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 81 (5): 644-652 MAY 15 2008
Abstract:
Photochromic diarylethene regioisomers having benzothiophene and benzofuran rings were synthesized and their
structures were confirmed by X-ray crystallography. The photochromic properties of these diarylethenes were examined
in solution as well as in the single-crystalline phase. We found that a diarylethene having 3-methylbenzofuran (FR2)
ring show photochromism upon irradiation with UV light. For bis(3-methylbenzofuran) (BFR2) derivatives, the
absorption band of the closed-ring isomer was longer than that of the open-ring isomer. The closed-ring isomer of the
diarylethene derivatives having one 2-methylbenzofuran (FR3) ring showed a high absorption coefficient (more than
104 dm(3) mol(-1) cm(-1)). Although the distance between two reactive carbon atoms was within 0.42 nm, some
diarylethene derivatives showed no photochromic reactions in the single-crystalline phase. Diarylethene derivatives
having one 2-methylbenzofuran (FR3) ring efficiently showed photochromism in the single-crystalline phase.
-------------------------------------------------------------------------------Record 6 of 13
Author(s): Poulos, AS (Poulos, Andreas S.); Constantin, D (Constantin, Doru); Davidson, P (Davidson, Patrick);
Imperor, M (Imperor, Marianne); Pansu, B (Pansu, Brigitte); Panine, P (Panine, Pierre); Nicole, L (Nicole, Lionel);
Sanchez, C (Sanchez, Clement)
Title: Photochromic hybrid organic-inorganic liquid-crystalline materials built from nonionic surfactants and
polyoxometalates: Elaboration and structural study
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Source: LANGMUIR, 24 (12): 6285-6291 JUN 17 2008
Abstract:
This work reports the elaboration and structural study of new hybrid organic-inorganic materials constructed via the
coupling of liquid-crystalline nonionic surfactants and polyoxometalates (POMs). X-ray scattering and polarized light
microscopy demonstrate that these hybrid materials, highly loaded with POMs (up to 18 wt %), are nanocomposites of
liquid-crystalline lamellar structure (L alpha), with viscoelastic properties close to those of gels. The interpretation of Xray scattering data strongly suggests that the POMs are located close to the terminal-OH groups of the nonionic.
surfactants, within the aqueous sublayers. Moreover, these materials exhibit a reversible photochromism associated to
the photoreduction of the polyanion. The photoinduced mixed-valence behavior has been characterized through ESR
and UV-visible-near-IR spectroscopies that demonstrate the presence of W-v metal cations and of the characteristic
intervalence charge transfer band in the near-IR region, respectively. These hybrid nanocomposites exhibit optical
properties that may be useful for applications involving UV-light-sensitive coatings or liquid-crystal-based
photochromic switches. From a more fundamental point of view, these hybrid materials should be very helpful models
for the study of both the static and dynamic properties of nano-objects confined within soft lamellar structures.
-------------------------------------------------------------------------------Record 7 of 13
Author(s): Bahajaj, AA (Bahajaj, A. A.); Asiri, AM (Asiri, A. M.)
Title: Photochromic properties of (E)-3(2-adamantylidene)-2-[5-(4-diethylaminophenyl)-2-methyl-3furylethylidene]
succinic anhydride doped in polystyrene film
Source: PIGMENT & RESIN TECHNOLOGY, 37 (3): 140-144 2008
Abstract:
Purpose - The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in
polymer matrices.
Design/methodology/approach - The polystyrene films doped with photochromic fulgide were prepared and the effect of
UV irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. The effect
of heat was also determined.
Findings - A film of the green coloured fulgide 2-E doped in polystyrene polymer was irradiated with UV light (366
nm), the film turned blue. The latter colour was partially switched back to the original green colour when the film was
irradiated with a white light. Increasing the annealing temperatures, increases the percentage conversion of 2-C to 2-E.
The observed large bathochromic shifts in lambda(max) of 2-C and the partial conversion of 2-C to 2-E were
rationalised on the bases of electronic and steric effects. it was found that both isomers 2-C and 2-E absorbed white light
and they interconvert. The kinetics of photocoloration and photobleaching processes were followed
spectrophotometrically by monitoring the absorbance of the ring closed product 2-C at its lambda(max) of 620 nm. The
apparent first-order rate constants for both processes were determined. it was found that there was slight variation in the
rate constant for photocoloration reaction with annealing temperature. On the other hand, the apparent first-order rate
constant of the photobleaching reaction decreases with increasing the annealing temperature.
Research limitations/implications - The polystyrene polymer doped photochromic fulgides described in the present
paper was prepared and studied. The principle of study established can be applied to any type of polymer or to any type
of photochromic compounds.
Practical implications - The photochromic materials developed can be used for different applications, such as coatings
and holography.
Originality/value - The method developed may be used to enhance the performance of photochromic materials.
-------------------------------------------------------------------------------Record 8 of 13
Author(s): Baghaffar, GA (Baghaffar, G. A.); Asiri, AM (Asiri, A. M.)
Title: The effects of organic additives on photochromism. Part 1: the photochromic performance of (E)dicyclopropylmethylene-(2,5-dimethyl-3-furylethylidene)-succinic anhydride and ferrocene containing dye doped in
PMMA polymer film
Source: PIGMENT & RESIN TECHNOLOGY, 37 (3): 145-150 2008
Abstract:
Purpose - To evaluate the photochromic performance of fulgide 1-E with ferrocene in polymer matrices.
Design/methodology/approach - The fulgide 1-E with ferrocene dye 2 doped in polymethylmethacrylate was prepared
and the effects of UV irradiation were studied using spectrophotometer. The reversible reaction was effected using
white light. The effect of heat was also determined.
Findings - A film of the brown coloured fulgide 1-E with ferrocene doped in PMMA polymer was irradiated with
ultraviolet light (365 nm), the film turned red. The later colour was partially switched back to the original brown colour
when the film was irradiated with a white light. It was found that the rate constants of photocoloration reaction at initial
stages are faster than those at late stages. Similarly, the photocoloration reaction was slower than the photobleaching
reaction. Photocoloration reaction decreased with the increase of the annealing temperatures, but for photobleaching
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reaction, the rates were almost similar (at 46 and 82 degrees C). The fatigue resistance of the film was greatly improved
when the annealing temperature increased to 82 degrees C.
Research limitations/implications - The polymethylmethacrylate polymer doped photochromic fulgide 1-E and
ferrocene 2 described in the present paper was prepared and studied. The principle of study established can be applied to
any type of polymer or to any type of photochromic compounds.
Practical implications - The photochromic materials developed can be used for different applications, such as coatings
and holography.
Originality/value - The method developed may be used to enhance the performance of photochromic materials.
-------------------------------------------------------------------------------Record 9 of 13
Author(s): Liu, JY (Liu, Juyan); Han, J (Han, Jie); Wei, YH (Wei, Yongheng); Yao, F (Yao, Fei); Pang, ML (Pang,
Meili); Meng, JB (Meng, Jiben)
Title: Synthesis, photochromic mechanism and properties of a novel biindenylidenedione compound containing
ferrocene units
Source: APPLIED ORGANOMETALLIC CHEMISTRY, 22 (6): 319-325 JUN 2008
Abstract:
A novel biindenylidenedione compound, [2,2'-bi-1H-indene]-3,3'-bis [(4-oxo-4-ferrocenylbutanoyloxy)propyl]-3,3'dihydroxy-1,1'-dione was synthesized and characterized fully by H-1 NMR, IR, MS and elemental analysis. The
photochromic and photo-induced radical properties were investigated by means of UV-vis and electron spin resonance
spectroscopy, respectively. The results show that the title compound simultaneously exhibits photochromism in the solid
state as well as generating stable free radicals under irradiation with 330 nm light. This fact provides evidence for the
photochromic mechanism of this kind of compounds. Copyright (C) 2008 John Wiley & Sons, Ltd.
-------------------------------------------------------------------------------Record 10 of 13
Author(s): Jiang, M (Jiang, Min); Jiao, TF (Jiao, Tifeng); Liu, MH (Liu, Minghua)
Title: Photochromic Langmuir-Blodgett films based on polyoxomolybdate and gemini amphiphiles
Source: NEW JOURNAL OF CHEMISTRY, 32 (6): 959-965 2008
Abstract:
Novel photochromic hybrid organized molecular films composed of polyoxomolybdate (PMo12) and a series of gemini
amphiphile (BisBC18Nn, n = 1, 2, 3) with different hydrophilic spacer length were fabricated by the Langmuir-Blodgett
(LB) technique. When these gemini amphiphiles were spread on an aqueous PMo12 subphase, hybrid monolayers were
formed in situ at the air/water interface through electrostatic interaction. These hybrid monolayers were subsequently
transferred onto solid substrates and characterized by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy
(FT-IR), X-ray diffraction (XRD), atomic force microscopy (AFM) and cyclic voltammetry (CV). The hybrid multilayer
films showed photochromic property, i.e., the color of BisBC18Nn/PMo12 hybrid films changed from pale yellow to
cyan under UV irradiation and decoloration occurred when the films were heated in the air. Such processes could be
repeated many times and the films exhibited excellent photochromic reversibility. A slight difference in the coloration
of the hybrid films with different spacer lengths was observed.
-------------------------------------------------------------------------------Record 11 of 13
Author(s): Mizuno, H; Kumar Mal, T; Waelchli, M; Kikuchi, A; Fukano, T; Ando, R; Jeyakanthan, J; Taka, J; Shiro, Y;
Ikura, M; Miyawaki, A
Title: Light-dependent regulation of structural flexibility in a photochromic fluorescent protein
Source: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF
AMERICA, eFIRST
Abstract:
The structural basis for the photochromism in the fluorescent protein Dronpa is poorly understood, because the crystal
structures of the bright state of the protein did not provide an answer to the mechanism of the photochromism, and
structural determination of the dark state has been elusive. We performed NMR analyses of Dronpa in solution at
ambient temperatures to find structural flexibility of the protein in the dark state. Light-induced changes in interactions
between the chromophore and beta-barrel are responsible for switching between the two states. In the bright state, the
apex of the chromophore tethers to the barrel by a hydrogen bond, and an imidazole ring protruding from the barrel
stabilizes the plane of the chromophore. These interactions are disrupted by strong illumination with blue light, and the
chromophore, together with a part of the beta-barrel, becomes flexible, leading to a nonradiative decay process.
-------------------------------------------------------------------------------Record 12 of 13
Author(s): Nakagawa, T (Nakagawa, Tetsuya); Hasegawa, Y (Hasegawa, Yasuchika); Kawai, T (Kawai, Tsuyoshi)
Title: Photoresponsive europium(III) complex based on photochromic reaction
Source: JOURNAL OF PHYSICAL CHEMISTRY A, 112 (23): 5096-5103 JUN 12 2008
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Abstract:
Luminescence properties and their photoinduced control of the electric dipole transitions of a Eu(III) complex that has
photochromic triangle terarylenes ligands, tris(hexafluoroacetylacetonato)bis[4,5- bis(5-methyl-2-phenylthiazol-4-yl)-2phenylthiazole]europium(III) (Eu(hfa)(3)(THIA)(2)), were studied. Fairly high photochromic reactivity of the ligand
between the open-ring and closed-ring forms were found to be maintained even in the complex, and reversible color
change could be observed many times. The photocyclization and the cycloreversion quantum yields of the
Eu(hfa)(3)(THIA)(2) were found to be 37% and 3.4%, respectively. The thermal stability of the closed-ring form of
THIA ligand is significantly improved in the Eu(III) complex. The D-5(0)-F-7(2) transition intensity of the Eu(III)
complex with open-ring form ligands (Eu(hfa)(3)(THIA)2-O) is larger than that of the Eu(III) complex with closed-ring
form ligands (Eu(hfa)(3)(THIA)2-C). The radiative rate constants of Eu(hfa)(3)(THIA)2-O and Eu(hfa)(3)(THIA)2-C
are estimated to be 1.7 x 10(2) and 1.5 x 10(2) s(-1), respectively. The reversible control of the emission properties of
the Eu(III) complex by the photochromic reactions is demonstrated for the first time.
-------------------------------------------------------------------------------Record 13 of 13
Author(s): Gong, SS (Gong, Shanshan); Fan, CB (Fan, Congbin); Liu, WJ (Liu, Weijun); Liu, G (Liu, Gang)
Title: 1-(2-chlorophenyl)-2-(2-methyl-5-phenyl-3-thienyl)-3,3,4,4,5,5-hexafluorocyclopent-1-ene: a new photochromic
diarylethene
Source: ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE, 64: O1028-U1745 Part 6
JUN 2008
Abstract:
The title compound, C22H13ClF6S, is a hybrid diarylethene derivative with one 3-thienyl substituent, and a Clsubstituted six-membered aryl unit bonded to the double bond of a hexafluorocyclopentene ring. In the crystal structure,
the molecule adopts a photo-active antiparallel conformation that can undergo effective photocyclization reactions. The
distance between the two reactive C atoms is 3.848 (3) angstrom. The dihedral angles between the least-squares
cyclopentene plane and those of the adjacent thiophene and chlorophenyl rings are 49.39(8) and 59.88 (8)degrees,
respectively. The F atoms are disordered over two positions, with site occupancy factors of 0.6 and 0.4.
Fiber Amplifier
Record 1 of 8
Author(s): Wen, SF (Wen, Senfar); Chi, S (Chi, Sien)
Title: Propagation characteristics of fast light in an erbium-doped fiber amplifier
Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (6): 1073-1080 JUN
2008
Abstract:
A perturbation method is used to study the interactions among the signal power, pump power, and metastable population
density for fast light in an erbium-doped fiber amplifier. The impact of temporal pump depletion (TPD) on fast light is
investigated in which TPD is the response of the pump power to the temporal variation of the metastable population
density. It is found that the gain coefficient and the absolute value of the negative group velocity are overestimated
without considering the TPD. The effects of high-order dispersions on fast light are also shown. (C) 2008 Optical
Society of America.
-------------------------------------------------------------------------------Record 2 of 8
Author(s): Bahrampour, AR (Bahrampour, A. R.); Farman, F (Farman, F.); Ghasempour, A (Ghasempour, A.)
Title: The moment method for fiber Raman amplifier gain ripple minimization
Source: OPTICS COMMUNICATIONS, 281 (14): 3673-3680 JUL 15 2008
Abstract:
We aim to propose a novel fiber Raman amplifier modeling based on the moment method, which is previously
introduced for modeling the inhomogeneous Erbium, doped fiber amplifiers and recently employed to analyze the fiber
Raman amplifier with continuous pump spectrum. In this model, the number of governing equations is independent of
the number of signals and according to the degree of accuracy it is proportional to the number of pumps. This method is
employed to analyze the Raman fiber amplifiers with an arbitrary input signal line shape and to minimize the gain ripple
of the fiber Raman amplifier with respect to the pump powers and pump frequencies. (C) 2008 Elsevier B.V. All rights
reserved.
-------------------------------------------------------------------------------Record 3 of 8
Author(s): Aozasa, S (Aozasa, Shinichi); Masuda, H (Masuda, Hiroji); Shimizu, M (Shimizu, Makoto); Yamada, M
(Yamada, Makoto)
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Title: Novel gain spectrum control method employing gain clamping and pump power adjustment in thulium-doped
fiber amplifier
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1274-1281 MAY-JUN 2008
Abstract:
In this paper, we propose a novel method for controlling the gain spectrum of a thulium-doped fiber amplifier (TDFA)
in the S-band. The conventional gain spectrum control method used for a silica erbium-doped fiber amplifier (EDFA)
cannot be applied to TDFAs because of the complicated fluctuation of the TDFA gain spectrum. Our proposed method
controls the gain spectrum by a combination of gain clamping and pump power adjustment. The algorithm for the
method is as simple as that for the conventional EDFA gain spectrum control method. Furthermore, we describe a
function for correcting the gain excursion generated by the incorporation of amplified spontaneous emission (ASE) at a
signal monitoring photodiode (PD). We achieved a gain excursion of 0.35 dB against a total input signal power of -32 to
-2 dBm.
-------------------------------------------------------------------------------Record 4 of 8
Author(s): Cheng, C (Cheng, Cheng)
Title: A multiquantum-dot-doped fiber amplifier with characteristics of broadband, flat gain, and low noise
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1404-1410 MAY-JUN 2008
Abstract:
Doped with PbSe nanocrystals of different sizes, a multiquantum-dot-doped fiber amplifier (MQDFA) is proposed.
Performance of the MQDFA is simulated by solving light-propagation equations and rate equations for a three-level
system, and by applying superposed emission-absorption cross sections of the quantum dots (QDs). Pumped with 980
nm, this proposed MQDFA has characteristics of broader band, flatter gain, and lower noise than those of the erbiumdoped fiber amplifiers at present. There is evidence to show that two factors, i.e., the equivalent Stokes shifts and the
full wave at half maximum of the superposed spectra, dominate the performances of the MQDFA. Also, the equivalent
Stokes shift and the FWHM are tunable by adopting the QDs in different sizes and choosing the doped number available.
It is expected that such a MQDFA may be able to cover the all waveband in telecommunications if it is optimized on the
doped number, sizes, and doped concentrations of the QDs.
-------------------------------------------------------------------------------Record 5 of 8
Author(s): Andermahr, N (Andermahr, N.); Fallnich, C (Fallnich, C.)
Title: Interaction of transverse modes in a single-frequency few-mode fiber amplifier caused by local gain saturation
Source: OPTICS EXPRESS, 16 (12): 8678-8684 JUN 9 2008
Abstract:
We report on the behavior of modal polarization states in a single-frequency, ytterbium-doped, few-mode fiber amplifier.
Experimental data show that the polarization of the individual transverse modes depends on the pump power and that
the modes tend towards orthogonally polarized states with increasing gain. The observations can be explained by local
gain saturation that favors the amplification of differently polarized modes. (c) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 6 of 8
Author(s): Lin, GR (Lin, Gong-Ru); Lee, CK (Lee, Chao-Kuei); Kang, JJ (Kang, Jung-Jui)
Title: Rational harmonic mode-locking pulse quality of the dark-optical-comb injected semiconductor optical amplifier
fiber ring laser
Source: OPTICS EXPRESS, 16 (12): 9213-9221 JUN 9 2008
Abstract:
We study the rational harmonic mode-locking (RHML) order dependent pulse shortening force and dynamic chirp
characteristics of a gain-saturated semiconductor optical amplifier fiber laser (SOAFL) under dark-optical-comb
injection, and discuss the competition between mode-locking mechanisms in the SOAFL at high-gain and strong optical
injection condition at higher RHML orders. The evolutions of spectra, mode-locking and continuous lasing powers by
measuring the ratio of DC/pulse amplitude and the pulse shortening force (I-pulse/P-avg(2)) are performed to determine
the RHML capability of SOAFL. As the rational harmonic order increases up to 20, the spectral linewidth shrinks from
12 to 3 nm, the ratio of DC/pulse amplitude enlarges from 0.025 to 2.4, and the pulse-shortening force reduces from 0.9
to 0.05. At fundamental and highest RHML condition, we characterize the frequency detuning range to realize the
mode-locking quality, and measure the dynamic frequency chirp of the RHML-SOAFL to distinguish the linear and
nonlinear chirp after dispersion compensation. With increasing RHML order, the pulsewidth is broadened from 4.2 to
26.4 ps with corresponding chirp reducing from 0.7 to 0.2 GHz and linear/nonlinear chirp ratio changes from 4.3 to 1.3,
which interprets the high-order chirp becomes dominates at higher RHML orders. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 7 of 8
Author(s): Kuo, BPP (Kuo, Bill Ping-Piu); Chui, PC (Chui, P. C.); Wong, KKY (Wong, Kenneth Kin-Yip)
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Title: A comprehensive study on crosstalk suppression techniques in fiber optical parametric amplifier by modulation
format
Source: IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, 14 (3): 659-665 MAY-JUN 2008
Abstract:
With the presence of multiple-WDM input signals, ON-OFF keying (OOK)-modulated signals suffer from crosstalk in
fiber optical parametric amplifier (OPA) due to cross-gain modulation (XGM) and four-wave mixing (FWM) effects.
We demonstrated substantial crosstalk suppression in one-pump OPA by using return-zero differential phase-shift
keying (RZ-DPSK) modulation format, which with its pattern-independent amplitude and subunity duty cycle would be
effective in reducing the XGM and FWM effects significantly. By using the RZ-DPSK format, the power penalty was
improved by at least 0.8 dB over RZ-OOK, non-RZ (NRZ)-DPSK, and NRZ-OOK formats with four 10 Gb/s channels,
separated by 200 GHz spacing. With eight 10 Gb/s channels separated by 100 GHz spacing, a Q-factor penalty of the
RZ-DPSK signal was reduced by 2.4 dB compared to RZ-OOK counterparts.
-------------------------------------------------------------------------------Record 8 of 8
Author(s): Romero-Alvarez, R (Romero-Alvarez, R.); Pettus, R (Pettus, R.); Wu, Z (Wu, Z.); Strickland, D (Strickland,
D.)
Title: Two-color fiber amplifier for short-pulse, mid-infrared generation
Source: OPTICS LETTERS, 33 (10): 1065-1067 MAY 15 2008
Abstract:
A short-pulse, two-color Yb:fiber laser system has been developed for mid-infrared generation. To date, 20 mu W of
average power at a wavelength of similar to 18 mu m is generated by difference-frequency mixing 300 mW average
power from the two-color Yb:fiber amplifier. The mid-infrared power was not limited by two-photon absorption,
allowing it to be scaled by increasing the amplifier power. (C) 2008 Optical Society of America.
Optic Communication
Record 1 of 10
Author(s): Riza, NA (Riza, Nabeel A.); Reza, SA (Reza, Syed Azer)
Title: High-dynamic-range hybrid analog-digital control broadband optical spectral processor using micromirror and
acousto-optic devices
Source: OPTICS LETTERS, 33 (11): 1222-1224 JUN 1 2008
Abstract:
For the first time, to the best of our knowledge, the design and demonstration of a programmable spectral filtering
processor is presented that simultaneously engages the power of an analog-mode optical device such as an acousto-optic
tunable filter and a digital-mode optical device such as the digital micromirror device. The demonstrated processor
allows a high 50 dB attenuation dynamic range across the chosen 1530-1565 mn (similar to C band). The hybrid analogdigital spectral control mechanism enables the processor to operate with greater versatility when compared to analog- or
digital-only processor designs. Such a processor can be useful both as a test instrument in biomedical applications and
as an equalizer in fiber communication networks. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 2 of 10
Author(s): Zoiros, KE (Zoiros, K. E.); Siarkos, T (Siarkos, T.); Koukourlis, CS (Koukourlis, C. S.)
Title: Theoretical analysis of pattern effect suppression in semiconductor optical amplifier utilizing optical delay
interferometer
Source: OPTICS COMMUNICATIONS, 281 (14): 3648-3657 JUL 15 2008
Abstract:
The ability of an optical delay interferometer (ODI) to suppress the pattern effect that is inherently present in a
straightforward, solitary semiconductor optical amplifier (SOA) whose dynamic response is slower than the period of its
driving high-speed return-to-zero (RZ) data signal is theoretically investigated. For this purpose an existing
comprehensive model that simulates and links the operation of these two elements is methodically applied to their
concatenated configuration. In this manner an extensive set of curves is numerically obtained, which allow to analyze
and assess the impact of the input pulse energy and width as well as of the SOA carrier lifetime, line-width enhancement
factor and small signal gain on the amplitude modulation of the transmitted sequence at the output of each one of these
block units. Their thorough study and interpretation reveals that the employment of the ODI can significantly reduce the
value of this quality metric resulting from a single SOA only. The main offered benefit, however, is that any technical
restrictions regarding the involved critical parameters can be considerably relaxed while at the same time their useful
operational range can be extended. These important findings highlight the necessity of placing this passive device after
the SOA and exploiting it in order to effectively alleviate the detrimental pattern-dependent degradation, This fact in
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conjunction with its overall practicality renders it a promising candidate for enhancing, within the frame of the proposed
scheme, the performance of SOAs that are employed as pure amplification elements in fiber-optic communication
systems and networking applications. (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 3 of 10
Author(s): Personick, SD (Personick, Stewart D.)
Title: Optical detectors and receivers
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1005-1020 MAY-JUN 2008
Abstract:
In this paper, I will review the subjects of optical detectors and optical receivers. I will do this from both a historical
perspective and looking ahead toward useful progress that may occur in the future. I will focus, at times, on the lessons
learned while performing my own research and development activities, and on how and why the technology has
changed. I will share a few anecdotes, which will shed some light on the innovation process-at least as I experienced it.
-------------------------------------------------------------------------------Record 4 of 10
Author(s): Tomlinson, WJ (Tomlinson, W. J.)
Title: Evolution of passive optical component technologies for fiber-optic communication systems
Source: JOURNAL OF LIGHTWAVE TECHNOLOGY, 26 (9-12): 1046-1063 MAY-JUN 2008
Abstract:
This paper reviews the evolution of passive optical components for fiber-optic communication systems, focusing on the
interaction between component technologies and the evolution of fiber-optic systems.
-------------------------------------------------------------------------------Record 5 of 10
Author(s): Fidler, F (Fidler, Franz); Wallner, O (Wallner, Oswald)
Title: Application of single-mode fiber-coupled receivers in optical satellite to high-altitude platform communications art. no. 864031
Source: EURASIP JOURNAL ON WIRELESS COMMUNICATIONS AND NETWORKING, 64031-64031 2008
Abstract:
In a free-space optical communication system employing fiber-optic components, the phasefront distortions induced by
atmospheric turbulence limit the efficiency with which the laser beam is coupled into a single-mode fiber. We analyze
different link scenarios including a geostationary (GEO) satellite, a high-altitude platform (HAP), and an optical ground
station (OGS). Single-mode coupled optically preamplified receivers allow for efficient suppression of background
noise and highly sensitive detection. While GEO-to-OGS communication suffers from atmospheric turbulence, we
demonstrate that GEO-to-HAP communication allows for close to diffraction-limited performance when applying tiptilt correction. Copyright (C) 2008 F. Fidler and O. Wallner.
-------------------------------------------------------------------------------Record 6 of 10
Author(s): Chen, QH (Chen, Q. H.); Wu, WG (Wu, W. G.); Wang, ZQ (Wang, Z. Q.); Yan, GZ (Yan, G. Z.); Hao, YL
(Hao, Y. L.)
Title: Optical design and performance of a novel multifunction optical device
Source: MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 50 (8): 2185-2189 AUG 2008
Abstract:
This letter presents a novel MEMS-based multifunction-integrated optical device capable of performing as variable
optical power splitter (VOPS), optical switch (OS), and variable optical attenuator (VOA). The device manipulates the
light with a binary-slope mirror driven by compound electrostatic actuator. The optical models for splitting and
attenuating are investigated, respectively. Ball-lensed fibers are assembled with the device to achieve high coupling
efficiency in this work Measurements reveal that the excess loss of the device is less Man 3 dB, and the controllable
attenuation range is up to 39 dB. Moreover, polarization-dependent loss is less than 0.7 dB. (C) 2008 Wiley Periodicals,
Inc.
-------------------------------------------------------------------------------Record 7 of 10
Author(s): Woo, KL (Woo, Kevin L.); Rieucau, G (Rieucau, Guillaume)
Title: Considerations in video playback design: Using optic flow analysis to examine motion characteristics of live and
computer-generated
Source: BEHAVIOURAL PROCESSES, 78 (3): 455-463 JUL 2008
Abstract:
The increasing use of the video playback technique in behavioural ecology reveals a growing need to ensure better
control of the visual stimuli that focal animals experience. Technological advances now allow researchers to develop
computer-generated animations instead of using video sequences of live-acting demonstrators. However, care must be
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taken to match the motion characteristics (speed and velocity) of the animation to the original video source. Here, we
presented a tool based on the use of an optic flow analysis program to measure the resemblance of motion
characteristics of computer-generated animations compared to videos of live-acting animals. We examined three distinct
displays (tail-flick (TF), push-up body rock (PUBR), and slow arm wave (SAW)) exhibited by animations of Jacky
dragons (Amphibolurus muricatus) that were compared to the original video sequences of live lizards. We found no
significant differences between the motion characteristics of videos and animations across all three displays. Our results
showed that our animations are similar the speed and velocity features of each display. Researchers need to ensure that
similar motion characteristics in animation and video stimuli are represented, and this feature is a critical component in
the future success of the video playback technique. (C) 2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 8 of 10
Author(s): Yang, J (Yang, Junbo); Su, XY (Su, Xianyu); Liu, XK (Liu, Xiankui); He, XB (He, Xiaobin); Lan, JL (Lan,
Jianlun)
Title: Design of polarisation-independent bidirectional 2 x 2 optical switch
Source: JOURNAL OF MODERN OPTICS, 55 (7): 1051-1063 2008
Abstract:
Optical switching plays a vital role in all optical communication and network. Various optical switchings have been
developed in recent years as a way to improve reliability problems and to build small size, robust integrated devices. A
novel low crosstalk, high switching speed, compact in structure, efficient in performance, polarisation independent, and
reversible 2 x 2 optical switching is proposed using a phase spatial light modulator (PSLM), a polarising beam-splitter
(PBS), a mirror, a half-wave plate (HWP) and a quarter-wave plate (QWP). The optical switching should be helpful in
the design of a large-scale switch matrix, and show considerable promise in the future of fibre optic networks.
-------------------------------------------------------------------------------Record 9 of 10
Author(s): Roesch, K (Roesch, Karin); Jadhav, AP (Jadhav, Ashutosh P.); Trimarchi, JM (Trimarchi, Jeffrey M.);
Stadler, MB (Stadler, Michael B.); Roska, B (Roska, Botond); Sun, BB (Sun, Ben B.); Cepko, CL (Cepko, Constance L.)
Title: The transcriptome of retinal miller glial cells
Source: JOURNAL OF COMPARATIVE NEUROLOGY, 509 (2): 225-238 JUL 10 2008
Abstract:
Muller glial cells are the major type of glia in the mammalian retina. To identify the molecular machinery that defines
Muller glial cell identity and function, single cell gene expression profiling was performed on Affymetrix microarrays.
Identification of a cluster of genes expressed at high levels suggests a Muller glia core transcriptome, which likely
underlies many of the functions of Muller glia. Expression of components of the cell cycle machinery and the Notch
pathway, as well as of growth factors, chemokines, and lipoproteins might allow communication between Muller glial
cells and the neurons that they support, including modulation of neuronal activity. This approach revealed a set of
transcripts that were not previously characterized in (Muller) glia; validation of the expression of some of these genes
was performed by in situ hybridization. Genes expressed exclusively by Muller glia were identified as novel markers. In
addition, a novel BAC transgenic mouse that expresses Cre in Muller glia cells was generated. The molecular
fingerprint of Muller glia provides a foundation for further studies of Muller glia development and function in normal
and diseased states.
-------------------------------------------------------------------------------Record 10 of 10
Author(s): Wang, H (Wang, Hao); Kumar, S (Kumar, Shiva); Xu, CQ (Xu, Changqing)
Title: Multiple path interference and differential modal delay reduction using spatial filters in a 4F system
Source: APPLIED OPTICS, 47 (13): 2290-2296 MAY 1 2008
Abstract:
Multiple path interference (MPI) and differential modal delay (DMD) are two major impairments in fiber optic
communication systems. MPI can be found in a few mode fibers in which a higher order mode propagates as a weak
replica of the signal and interferes with the fundamental mode at the output of the fiber link. DMD in multimode fibers
(MMF) leads to intersymbol interference, which limits the bit rate-distance product of the system. A simple method is
proposed to reduce MPI and DMD effects using spatial filters in a 4F system. Higher order modes have higher spatial
frequency components. Therefore by choosing a proper spatial filter with a suitable bandwidth, a fraction of the
unwanted higher order modes can be suppressed, and therefore MPI and DMD effects can be reduced. (C) 2008 Optical
Society of America.
Large Aperture Mirror
Record 1 of 11
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Author(s): Suzuki, H (Suzuki, H.); Onishi, T (Onishi, T.); Moriwaki, T (Moriwaki, T.); Fukuta, M (Fukuta, M.);
Sugawara, J (Sugawara, J.)
Title: Development of a 45 degrees tilted on-machine measuring system for small optical parts
Source: CIRP ANNALS-MANUFACTURING TECHNOLOGY, 57 (1): 411-414 2008
Abstract:
A new contact type of on-machine measuring system is developed in order to measure aspherical optical parts with steep
surface angle for large numerical aperture (NA). A ceramic air slider made of SIALON is adopted for the measurement
probe because of its low thermal expansion coefficient, high rigidity and light weight. A high accuracy glass scale is
employed to reduce the thermal drift of the displacement gauge. The air slider or the measuring probe is tilted for 45
degrees against the aspherical workpiece, axis, and the probe is scanned over the workpiece surface, so as to keep the
contact angle between the probe axis and the contact surface constant in order to reduce the change in the probe friction
force. (c) 2008 CIRP.
-------------------------------------------------------------------------------Record 2 of 11
Author(s): Bhushan, R (Bhushan, Ravi); Yoshida, H (Yoshida, Hidetsugu); Tsubakimoto, K (Tsubakimoto, Koji); Fujita,
H (Fujita, Hisanori); Nakatsuka, M (Nakatsuka, Masahiro); Miyanaga, N (Miyanaga, Nobuaki); Izawa, Y (Izawa,
Yasukazu); Ishizuki, H (Ishizuki, Hideki); Taira, T (Taira, Takunori)
Title: High efficiency and high energy parametric wavelength conversion using a large aperture periodically poled
MgO : LiNbO3
Source: OPTICS COMMUNICATIONS, 281 (14): 3902-3905 JUL 15 2008
Abstract:
We have demonstrated an efficient high energy 2 mu m laser generation with a 36 mm long large aperture 5 mol%
MgO-doped periodically poled LiNbO3 (PPMgLN) nonlinear optical crystal. A high power Q-switched Nd:YAG laser
(1.064 mu m) was used to pump the quasi-phase matched (QPM) optical parametric oscillator (OPO). A total output
energy of 186 mJ with 58% slope efficiency was obtained in two separate beams at 2 mu m. (C) 2008 Elsevier B.V. All
rights reserved.
-------------------------------------------------------------------------------Record 3 of 11
Author(s): Hoedjes, JCB (Hoedjes, J. C. B.); Chehbouni, A (Chehbouni, A.); Jacob, F (Jacob, F.); Ezzahar, J (Ezzahar,
J.); Boulet, G (Boulet, G.)
Title: Deriving daily evapotranspiration from remotely sensed instantaneous evaporative fraction over olive orchard in
semi-arid Morocco
Source: JOURNAL OF HYDROLOGY, 354 (1-4): 53-64 JUN 15 2008
Abstract:
Hydrology and crop water management require daily values of evapotranspiration ET at different time-space scale. Sun
synchronous optical remote sensing, which allows for the assessment of ET with high to moderate spatial resolution,
provides instantaneous estimates during satellites overpass. Then, usual solutions consist of extrapolating instantaneous
to daily values by assuming that evaporative fraction EF is constant throughout the day, providing that daily available
energy AE is known. The current study aims at deriving daily ET values from ASTER derived instantaneous estimates,
over an olive orchard in a semi-arid region of Moroccan. It has been shown that EF is almost constant under dry
conditions, but it depicts a pronounced concave up shape under wet conditions. A new heuristic parameterization is then
proposed, which is based on the combination of routine daily meteorological data for characterizing atmospheric
dependence, and on optical remote sensing based estimates of instantaneous EF values to take into account the
dependence on soil and vegetation conditions. Using the same type of approach, a similar parameterization is next
developed for AE. The validation of both approaches shows good performances. The overall method is finally applied to
ASTER data. Though performances are reasonably good, their moderate reduction is ascribed to errors on remotely
sensed variables. Future-works will focus on method portability since its empirical formulation does not account for the
direct stomata[ response to water availability, as well as on application over different surface and climate conditions. (c)
2008 Elsevier B.V. All rights reserved.
-------------------------------------------------------------------------------Record 4 of 11
Author(s): Kaab, A (Kaab, Andreas)
Title: Remote sensing of permafrost-related problems and hazards
Source: PERMAFROST AND PERIGLACIAL PROCESSES, 19 (2): 107-136 APR-JUN 2008
Abstract:
Modern remote sensing techniques can help in the assessment of permafrost hazards in high latitudes and cold
mountains. Hazard development in these areas is affected by process interactions and chain reactions, the ongoing shift
of cryospheric hazard zones due to atmospheric warming, the large spatial scales involved and the remoteness of many
permafrost-related threats. This paper reviews ground-based, airborne and spaceborne remote sensing methods suitable
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for permafrost hazard assessment and management. A wide range of image classification and change detection
techniques support permafrost hazard studies. Digital terrain models (DTMs) derived from optical stereo, synthetic
aperture radar (SAR) or laser scanning data are some of the most important data sets for investigating permafrost-related
mass movements, thaw and heave processes, and hydrological hazards. Multi-temporal optical or SAR data are used to
derive surface displacements on creeping and unstable frozen slopes. Combining DTMs with results from spectral
image classification, and with multi-temporal data from change detection and displacement measurements significantly
improves the detection of hazard potential. Copyright (c) 2008 John Wiley & Sons, Ltd.
-------------------------------------------------------------------------------Record 5 of 11
Author(s): Ward, BG (Ward, Benjamin G.)
Title: Bend performance-enhanced photonic crystal fibers with anisotropic numerical aperture
Source: OPTICS EXPRESS, 16 (12): 8532-8548 JUN 9 2008
Abstract:
Numerical calculations predict that particular birefringent photonic crystal fiber designs exhibit slightly better
performance in a coiled configuration than non-birefringent step-index fiber designs with respect to higher order mode
suppression for the realization of large mode area effectively single transverse mode fibers. The passive losses of the
fundamental and first few higher order modes of a birefringent photonic crystal fiber design with a 41 m m diameter
core incorporating stress applying parts (SAP) were calculated using an integrated electromechanical finite element
method. Minimum higher order mode losses of up to 5.5 dB/m were predicted for fundamentalmode losses of only
0.0014 dB/m. The bend performance of this PCF design was predicted to be relatively insensitive to manufacturing
tolerances with respect to air hole size and device assembly tolerances with respect to coiling diameter based on the
calculated dependence of the mode losses on these parameters. The positions and refractive index of the SAP render the
numerical aperture of the core anisotropic allowing further tailoring of the bend performance by adjusting the angle
between the coiling plane of the fiber and the orientation of the SAP within the cladding. Fundamental and higher-order
mode losses are calculated for step-index fiber (SIF) designs with a 40 m m diameter core for comparison. The stepindex fiber designs were predicted to exhibit slightly inferior bend loss mode discrimination and higher sensitivity to
packaging configuration compared to the photonic crystal fiber designs presented. (C) 2008 Optical Society of America.
-------------------------------------------------------------------------------Record 6 of 11
Author(s): Seregin, AG (Seregin, A. G.); Smirnov, AP (Smirnov, A. P.); Seregin, DA (Seregin, D. A.); Bagrov, AV
(Bagrov, A. V.)
Title: Combining a stellar interferometer with an astronomical telescope to monitor the phasing that accompanies
aperture synthesis
Source: JOURNAL OF OPTICAL TECHNOLOGY, 75 (5): 314-320 MAY 2008
Abstract:
This paper discusses a version of a stellar interferometer in which the primary mirrors of the receiver telescopes have
different diameters. A small telescope serves as the reference channel for a large-diameter astronomical telescope. The
exit apertures of the channels are conjugate in the modified scheme, and the interference pattern is observed over the
entire pupil. It is shown that a technique of broadening the dynamic range of recording of the zero path difference in
white light by means of moire in the spectral interference pattern can be used in this case. (C) 2008 Optical Society of
America.
-------------------------------------------------------------------------------Record 7 of 11
Author(s): Zdunek, A (Zdunek, Adam); Rachowicz, W (Rachowicz, Waldemar)
Title: Cavity radar cross section prediction
Source: IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (6): 1752-1762 JUN 2008
Abstract:
Alternative models are discussed for the determination of the interior irradiation contribution to the radar cross section
(RCS) of open-ended cavities. Typical applications of practical interest include radiation field prediction of open-ended
waveguides and signature prediction of jet engine air intakes and exhaust outlets. It is shown and explained why the
classic perfectly conducting (PEC) ground plane (GP) model sometimes predicts measured cavity RCS very poorly.
Examples where PEC GP model predictions are 5 dB or more off are provided. Verifications that the used PEC GP
model is correctly implemented are provided. A physical optics based modification of the classic PEC GP model is
provided and explained. A novel model where the cavity aperture forms an opening in an infinite radar absorbing (IBC)
screen is proposed verified and validated. The IBC model resembles the common experimental set-up, and poses an
efficient novel halfspace type replacement model approximating a full space setting. The modified PEC GP model or
the IBC model can be used interchangeably for cavities with electrically large apertures.
-------------------------------------------------------------------------------Record 8 of 11
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Author(s): Xu, Y (Xu, Y.); Macaulay, MC (Macaulay, M. C.); Jowitt, FA (Jowitt, F. A.); Clarke-O'Neill, SR (ClarkeO'Neill, S. R.); Fader, MJ (Fader, M. J.); van den Heuvel, EA (van den Heuvel, E. A.); Cottenden, AM (Cottenden, A.
M.)
Title: A computerised real-time measurement system to locate the position of the urine stream in designing urine
collection devices for women
Source: MEDICAL ENGINEERING & PHYSICS, 30 (4): 531-537 MAY 2008
Abstract:
A computerised real-time measurement system has been developed and tested for locating the position of the urine
stream into a handheld urinal and onto a body-worn pad using arrays of resistive or optical sensors. Experimental data
indicates that urine streams were usually scattered over quite a large cross-sectional area (typically 30 mm in the
anterior/posterior direction) at the point of entry into handheld urinals. However, a correctly placed aperture of length 90
mm would have successfully received all the urine from the total of 36 clinical experiments run with seven women.
Similarly, experiments to determine the initial position of the urine stream onto body-worn pads indicated that a target
area of length 120 mm would have received the initial stream of urine from all 54 clinical experiments with 18 women.
These data have been used to help with the design of a handheld urinal and a body-worn urine collection interface (the
latter using the body-worn pad data) to be used in two variants of a new urine collection device for women (NICMS).
Although both resistive and optical sensors provided useful data, the reliability of optical sensors was often
compromised by droplets of urine splashing onto light sources or detectors. Future work should focus on protecting
them from splashing. (C) 2007 IPEM. Published by Elsevier Ltd. All rights reserved.
-------------------------------------------------------------------------------Record 9 of 11
Author(s): Hirakawa, S (Hirakawa, Shoichiro); Kawamata, J (Kawamata, Jun); Suzuki, Y (Suzuki, Yasutaka); Tani, S
(Tani, Seiji); Murafuji, T (Murafuji, Toshihiro); Kasatani, K (Kasatani, Kazuo); Antonov, L (Antonov, Liudmil);
Kamada, K (Kamada, Kenji); Ohta, K (Ohta, Koji)
Title: Two-photon absorption properties of azulenyl compounds having a conjugated ketone backbone
Source: JOURNAL OF PHYSICAL CHEMISTRY A, 112 (23): 5198-5207 JUN 12 2008
Abstract:
Two-photon absorption (TPA) properties of newly synthesized conjugated ketone derivatives that include nonalternant
azulenyl moieties in the pi-conjugation system, alpha,alpha'-bis(1-azulenylidene)cyclopentanone (1Az), alpha,alpha'bis(2-azulenylidene)cyclopentanone (2Az), and alpha,alpha'-bis(6-azulenylidene)cyclopentanone (6Az) are reported.
TPA spectra of these azulenyl compounds were measured using the open-aperture Z-scan method with a femtosecond
laser. The TPA cross section at the peak position (sigma((2))(peak)) of 1Az was found to be the laraest among the three
azulenyl compounds, which is almost 7 times larger than that of the alpha,alpha'-bis(1-naphthylidene)cyclopentanone
(1Nph), an alternant isomer of 1Az with the same number of pi-electrons. The small detuning energies of the azulenyl
compounds compared to those of 1Nph were responsible for the large TPA cross sections. We report that a compound
having an azulenyl moiety can be a promising TPA material.
-------------------------------------------------------------------------------Record 10 of 11
Author(s): MacArthur, LA (MacArthur, Lauren A.); Ellis, RS (Ellis, Richard S.); Treu, T (Treu, Tommaso); Vivian, U
(Vivian, U.); Bundy, K (Bundy, Kevin); Moran, S (Moran, Sean)
Title: The evolutionary history of galactic bulges: Photometric and spectroscopic studies of distant spheroids in the
GOODS fields
Source: ASTROPHYSICAL JOURNAL, 680 (1): 70-91 JUN 10 2008
Abstract:
We report on the first results of a new study aimed at understanding the diversity and evolutionary history of distant
galactic bulges in the context of now well-established trends for pure spheroidal galaxies. To this end, bulges have been
isolated for a sample of 137 spiral galaxies within the redshift range 0.1 < z < 1.2 in the GOODS fields. Using proven
photometric techniques, we determine the characteristic parameters (size, surface brightness, profile shape) of both the
disk and bulge components in our sample. In agreement with earlier work that utilized aperture colors, distant bulges
show a broader range of optical colors than would be the case for passively evolving populations. To quantify the
amount of recent star formation necessary to explain this result, we used DEIMOS to secure stellar velocity dispersions
for a sizeable fraction of our sample. This has enabled us to compare the fundamental plane of our distant bulges with
that for spheroidal galaxies in a similar redshift range. Bulges of spiral galaxies with a bulge-to-total luminosity ratio
(B/T) > 0.2 show similar patterns of evolution to those seen for pure spheroidals such that the stellar populations of all
spheroids with M > 10(11) M-circle dot are consistent with a single major burst of star formation at high redshift (z(f)
greater than or similar to 2), while bulges with M < 10(11) M-circle dot must have had more recent stellar mass growth
(similar to 10% in mass since z similar to 1). Although further data spanning a wider range of redshift and mass are
desirable, the similarity between the assembly histories of bulges and low-mass spheroidals seems difficult to reconcile
with the picture whereby the majority of large bulges form primarily via secular processes within spiral galaxies.
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-------------------------------------------------------------------------------Record 11 of 11
Author(s): Yang, QH (Yang, Qinghua); Zhou, RK (Zhou, Renkui); Zhao, BC (Zhao, Baochang)
Title: Principle of the moving-mirror-pair interferometer and the tilt tolerance of the double moving mirror
Source: APPLIED OPTICS, 47 (13): 2486-2493 MAY 1 2008
Abstract:
A novel type of interferometer, the moving-mirror-pair interferometer, is presented, and its principle and properties are
studied. The new interferometer is built with three flat mirrors, which include two flat moving mirrors fixed as a single
moving part by a rigid structure and one flat fixed mirror. The optical path difference (OPD) is obtained by the straight
reciprocating motion of the double moving mirror, and the OPD value is four times the physical shift value of the
double moving mirror. The tilt tolerance of the double moving mirror of the novel interferometer is systematically
analyzed by means of modulation depth and phase error. Where the square aperture is concerned, the formulas of the tilt
tolerance were derived. Due to the novel interferometer's large OPD value and low cost, it is very applicable to the highspectral-resolution Fourier-transform spectrometers for any wavenumber region from the far infrared to the ultraviolet.
(C) 2008 Optical Society of America.
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