chemistry and materials research at the interface between science

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HEMISTRY AND

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ESEARCH AT THE

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CIENCE AND

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Report of a Workshop Cosponsored by the

National Science Foundation and the Andrew W. Mellon Foundation

July 6–7, 2009

Arlington, Virginia

Co-Chairs

Marco Leona

Department of Scientific Research

The Metropolitan Museum of Art

Richard Van Duyne

Department of Chemistry

Northwestern University

Barbara Berrie

Scientific Research

Department

National Gallery of Art

Steering Committee

Francesca Casadio

Conservation Department

Art Institute of Chicago

Richard R. Ernst

Laboratorium für

Physikalische Chemie

ETH Zürich

Katherine T. Faber

Department of Materials

Science and Engineering


Antonio Sgamellotti


Universita’ degli Studi di Perugia

Karen Trentelman

The Getty Conservation Institute

The J. Paul Getty Trust

Paul Whitmore

Department of Chemistry and the Art

Conservation Research Center

Carnegie Mellon University

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UMMARY

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I NTRODUCTION

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G RAND C HALLENGE 3: M ATERIALS S TABILIZATION , S TRENGTHENING ,

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DUCATION AND

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R ESOURCES N EEDED FOR A DVANCING C HEMISTRY AND

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ONCLUSIONS

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A

PPENDICES

A: Additional Recommendations From Breakout Sessions

B. Workshop Participants

C. Workshop Schedule

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Cover Image: Elemental analysis by X-‐ray fluorescence spectroscopy showed that this Roman sculpture at The Metropolitan Museum of Art was once painted with a blue, copper-‐containing pigment such as azurite or Egyptian Blue. (Photo: The Metropolitan Museum of Art)

C HEMISTRY AND M ATERIALS R ESEARCH AT THE I NTERFACE B ETWEEN S CIENCE AND A RT

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UMMARY

T he objects that make up a portion of our cul-‐ tural heritage—from ancient artifacts to modern art pieces—have physical lives.

They change over time, respond to their environ-‐ ments, and eventually break down. The study of the materials that make up these objects, and the changes they undergo, is the province of cultural heritage scientists. The field of cultural heritage science, or conservation science, is vast and com-‐ plex, encompassing analytical and physical chem-‐ istry, biology, engineering, and materials science.

To advance the field of cultural heritage sci-‐ ence, chemists and materials scientists from mu-‐ seums, universities, national laboratories, industry, and other institutions came together for

Chemistry and Materials Research at the Interface

Between Science and Art , a workshop cosponsored by the Andrew W. Mellon Foundation and the Na-‐ tional Science Foundation. The participants dis-‐ cussed three scientific challenges in the study and preservation of cultural heritage: materials and structures; degradation and aging; and stabiliza-‐ tion, strengthening, and repair. This report out-‐ lines the discussions of this diverse group of specialists, which covered the scientific drivers of this work, the research needed to continue ad-‐ vancing the field, and initiatives in education and funding.

The workshop participants highlighted the im-‐ portance of a fundamental understanding—at mo-‐ lecular and microstructural levels—of cultural heritage materials. This knowledge will provide information about past cultures, civilizations, and technologies, and enhance our ability to preserve the world’s material culture. More specifically, the scientific ideas driving cultural heritage science research are: the fundamental description of com-‐ plex materials and structures, the understanding of material changes in cultural objects, and the ef-‐ ficient design of effective and safe conservation treatments. Examples of recommendations to meet the three challenges include:

•

Development of analytical probes with high sensitivity and spatial resolution

(ranging from small to large scale), for re-‐ stricted volume, as well as standoff detec-‐ tion of component materials, degradation products, and deterioration markers

•

Study of ultraslow changes in materials, occasionally in severely degraded states or in small populations in which each object has a unique history

•

Compatibility-‐driven design for multifunc-‐ tional treatment materials

•

Theoretical modeling of materials and structures that acknowledges the complex-‐ ity of authentic objects and their various aging processes

The workshop attendees confirmed that the field will continue to prosper through the building of broad-‐based partnerships between scientists at universities, national laboratories, and cultural heritage institutions such as museums. Only such collaboration will bring necessary advances in sensing technologies, nanoscience, materials de-‐ sign, and theoretical modeling into cultural heri-‐ tage research. Further network-‐building opportunities may come through international col-‐ laborations, particularly with academic institu-‐ tions in Europe. The workshop discussions also highlighted the need for a sustained funding effort on the part of the National Science Foundation, through a variety of tools such as development grants; initiatives for workforce development; small grants for exploratory research; multiyear research grants; support for workshops, confer-‐ ences, and web-‐based networking initiatives; and the creation of research centers.

The information that can be gained through the scientific investigation of cultural heritage ma-‐ terials has clear impact and relevance in basic sci-‐ ence, the humanities, and education. The incorporation of cultural heritage research into curricula is a highly effective means to attract and inspire the next generation of scientists, and the field can reach new audiences for science through museum-‐ and cultural heritage institution-‐based programming, such as exhibitions, public lectures, and electronic and mass media. Only a concerted effort to grow and interlink the cultural heritage science community in the United States will realize these benefits.


3

I

NTRODUCTION

I t is all too easy, as one walks through a mu-‐ seum, to forget that the works of art that in-‐ spire and enlighten us are tangible, physical objects that age and break down in ways that we

A group of forty-‐two chemists and materials scientists from cultural heritage institutions, uni-‐ versities, national laboratories, and private indus-‐ try met in Arlington, Virginia, from July 6–7, 2009, may or may not see. Almost all of them have al-‐ ready outlived their creators and in many cases even their creators’ imaginations; they exist hun-‐ dreds or even thousands of years beyond what their makers intended. Cultural heritage objects— from archaeological artifacts of the deep human past, to contemporary pieces made of synthetic materials, to buildings and monuments—live physical lives, subject to the environments in which they are exhibited or stored and all the little insults, inadvertent and deliberate, that come with it.

Preserving these items is the realm of art and archaeological conservators, but studying their material makeup, the way to take part in a workshop titled Chemistry and

Materials Research at the Interface Between Science and Art . The National Science Foundation (NSF)-‐ and Andrew W. Mellon Foundation-‐sponsored workshop explored the basic scientific questions relating to the understanding and preservation of cultural heritage materials, defined short-‐ and long-‐term priorities for research, and initiated in-‐ teraction be-‐ tween scientists in cultural heri-‐ tage institutions and their peers in universities and national laboratories.

Cultural heritage—the subject of the workshop— includes all the material evi-‐ dence of hu-‐ mankind’s accomplish-‐ ments: archaeo-‐ that they age and deteriorate, and new methods to

Fig. 1 – Raman microspectroscopy, a technique that provides molecular information about an object without requiring a sample, is used to identify the pigments in a painted glass plate attributed to German artist Hans Wertinger and dated to 1498. (Photo: The Metropolitan Museum of Art) preserve and restore them is the province of scientists. The field of cultural heritage science, or conservation sci-‐ logical objects and sites, cul-‐ tural properties, fine arts collec-‐ tions, archives, historical buildings, monuments, and other sites. In materials science, the deteriora-‐ ence, is vast and complex, encompassing analytical and physical chemistry, biology, engineering, and materials science.

1

1 Additional background material on the field of cultural heritage science can be found at: Nazaroff, W. W., and B. Amadei, “New Tech-‐ nologies and Cultural Heritage: A U. S.–Italian Bilateral Workshop,” held in Venice, Italy, April 23-‐24, 2001, NSF award no. 0119379

(2001); “Scientific examination of art: modern techniques in conser-‐ vation and analysis,” Sackler colloquium chaired by T. Wiesel and R.

Hoffmann, organized by B. Berrie, E. R. de la Rie, J. Tomlinson, and J.

Winter, held at the National Academy of Sciences, Washington DC,

March 19–21, 2003; and Paul M. Whitmore, coordinating author.

Conservation Science Research: Activities, Needs and Funding Opportu- tion of a material is assessed on the basis of its

“performance.” Naturally, the performance charac-‐ teristics of an art object can be difficult to deter-‐ mine, but can include anything from its structural integrity, to the intensity of its colors, to our ability to extract useful information from it. And these objects are often highly complex mixtures of mate-‐ rials, many of which haven’t been produced for

nities. A Report to the National Science Foundation.

(2005) mac.mellon.org/NSF-‐MellonWorkshop/

Whitmore%20White%20paper.pdf.


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centuries, that interact and react with one another in unexpected ways.

As a result of these complexities, scientific re-‐ search on the components, structure, and degrada-‐ tion processes of cultural heritage objects has grown over the last three decades into a large, so-‐ phisticated, multidisciplinary, and technically ad-‐ vanced field. Today, cultural heritage scientists use single-‐molecule spectroscopies and noninvasive methods to identify materials, sensing techniques to monitor environments, and computer-‐aided im-‐ aging and modeling to explore objects and their breakdown processes. The ultimate goal of the field is to improve our ability to preserve the world’s artistic and cultural patrimony, and it is a rich repository of basic scientific questions.

Cultural heritage scientists come from the fields of chemistry, physics, materials science, and biology, and are based in art museums, libraries, government laboratories, and, to a lesser degree, universities. Currently, the majority of applied sci-‐ entific research into cultural heritage materials is carried out in museum-‐based laboratories, while university laboratories focus more on fundamental research and technological advances. A major leap in the understanding of cultural heritage objects and their material issues and conservation is pos-‐ sible by bringing these approaches together— fostering partnerships between scientists in mu-‐ seums who apply new technologies and those in universities and national laboratories who develop them.

Cultural heritage science simultaneously pur-‐ sues several goals: understanding the deteriora-‐ tion of art objects, developing new treatments for conservation and restoration, and providing in-‐ formation about the past or the artists’ intentions.

Unfortunately, issues with cultural heritage often are presented to scientists when there are prob-‐ lems that cannot be addressed by more traditional


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conservation techniques. Furthermore, the degree to which cultural heritage materials are subject to deteriorating processes is increasing. We can no longer afford a triage approach, so we must de-‐ velop a coordinated, multifaceted, and sustainable research program to study pieces of cultural heri-‐ tage before they reach a critical stage.

This is particularly challenging for practitio-‐ ners of cultural heritage science because they are subject to constraints that rarely affect other chemists and materials scientists. Cultural heritage objects are irreplaceable, so any analytical investi-‐ gations must be noninvasive and nondestructive, or at the very least require minimal sampling. Any conservation treatments that result from these studies must be compatible with the original ob-‐ jects and completely reversible. In addition, cul-‐ tural heritage objects have existed and will exist over long time spans, and the manner in which they have been treated and stored is often un-‐ known. Therefore, accurately predicting how a particular object—often made of a mixture of ma-‐ terials that may interact—will age is multifactorial and mind-‐bendingly complex, with different com-‐ ponents aging at different rates under different conditions over the lifetime of an object. Moreover, natural, ultraslow aging processes may not match up with laboratory-‐accelerated aging tests, and the degradation products of one material might accel-‐ erate or retard the deterioration of another. But these constraints and challenges do provide bene-‐ fits to scientific inquiry—they are strong catalysts for the development of new technologies with broad application. The field has high scientific merit in both basic and applied research.

Advances in analytical chemistry and materials science, in addition to nanotechnology and bio-‐ medical research, will increase our knowledge of components and structures of cultural heritage artifacts. The complexity of cultural heritage pro-‐ vides a demanding proving ground for new ana-‐ lytical techniques and instrumentation, which allows conservation science to contribute to basic research in these complementary fields. For ex-‐ ample, recent advances in plasmonics supports for surface-‐enhanced Raman scattering have been successfully applied to the identification of dyes of archaeological interest, and in turn the instrumen-‐ tation and techniques developed by cultural heri-‐ tage scientists have been successfully implemented in industrial applications and re-‐ search in other areas. The same holds true for computational design of materials that can be used in repair and restoration. Basic research in this area can be applied to cultural heritage science, where the materials created must meet challeng-‐ ing requirements of chemical compatibility, resis-‐ tance to corrosion and color change, thermal stability, and thermal expansion to match with the original materials of a cultural object. Advances under such rigorous conditions can in turn be ap-‐ plied to problems in other fields.

Beyond scientific merit, cultural heritage sci-‐ ence provides a number of other social benefits.

The primary and most obvious of these is the long-‐ lasting preservation of the world’s shared cultural objects, so that they can be admired, treasured, and learned from for centuries. It is impossible to assess how much has already been lost to conflict and thoughtlessness; Nobel-‐Laureate chemist

Richard Ernst, who gave the workshop’s keynote address, described the conservation and restora-‐ tion of cultural heritage as a primary responsibility of our time. This is a lasting benefit, extending be-‐ yond the lifetime of the scientists and conserva-‐ tors. In addition, the field provides bridges between basic research, applied science, and the humanities, adding immediate social relevance to the practice of science. As an example of use-‐ inspired research, the field attracts generations of students to basic science, and has demonstrated great potential in improving gender representa-‐ tion and educational opportunities for underprivi-‐ leged youths through museums in large cities and heritage centers in rural areas. And more recently, cultural heritage science has become an attractive option for undergraduate students from urban, rural, or tribal backgrounds.

The current state of cultural heritage science is strong, but there is an urgent need to break down boundaries further to link disparate efforts in fun-‐ damental research into a robust, integrated vision for the future of the field. This workshop was con-‐ vened to determine the path forward. The distin-‐ guished experts were invited to identify the most pressing questions for the future of the field, es-‐ tablish long-‐term interaction between scientists at universities and national laboratories with those at cultural heritage institutions, and outline near-‐ and long-‐term priorities. Following presentations by the workshop planners, participants were di-‐ vided into fluid breakout groups to discuss three


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Grand Challenges in the field: the development of analytical techniques, the investigation of deterio-‐ ration processes, and the development of new con-‐ servation methods and materials. The discussions were wide-‐ranging. This report consists of sections focusing on each of the three Grand Challenges and the enabling research areas that will help meet those challenges, the resources needed for the con-‐ tinued growth of cultural heritage science, and ways to nurture the broader impact of the field.

In many ways, Europe has an enviable model for the development of cultural heritage science. In the United States, this work traditionally has been carried out in museums, libraries, and other cul-‐ tural heritage institutions, with researchers based in academia and national laboratories only occa-‐

sionally and inconsistently involved. Across the

Atlantic, however, financial support from the

European Union has been considerable, resulting in multinational and multi-‐institution partner-‐ ships. The NSF can play a key role in promoting and supporting just this sort of collaboration, which is not only desirable but necessary. The

NSF’s emphasis on inter-‐ and multidisciplinary work is well suited to a sustained effort in basic research that breaks boundaries between various types of institutions. Establishing a unifying direc-‐ tive for the field and supporting collaboration will significantly accelerate the rate of discovery, facili-‐ tate the transfer of information to cultural heritage applications, and enhance the development of educational activities. This workshop is a critical first step in stimulating discovery, innovation, and education.

Fig. 2 – Gas chromatography-mass spectrometry, used here by Julie Arslanoglu and Adriana Rizzo of The Metropolitan

Museum of Art, is the standard technique for identifying organic materials in paints and varnishes. Using a microscopic sample, it can determine the paint or varnish used by the ratios of different chemical constituents. (Photo: The Metropoli- tan Museum of Art)


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O ne of the first steps in studying an irre-‐ placeable or precious object with cultural heritage value is characterizing the materi-‐ als from which it is made and their structure. To nondestructive, and are often conducted on highly complex materials. However, these constraints provide great opportunities for the development of new, advanced measurement science and imag-‐ do this, cultural heritage scientists use analytical tests—such as atomic force microscopy, mass spectrometry, Raman spectroscopy, and others.

The first of the three Grand Challenges dealt with analytical technologies. Workshop Steering Com-‐ mittee member Francesca Casadio, Andrew W.

Mellon Senior Conservation Scientist at the Art

Institute of Chicago, spoke to the attendees about the topic before they were separated into discus-‐ sion groups.

A clear understanding of the materials that compose objects of artistic, historic, anthropologi-‐ cal, and archaeological significance is fundamen-‐ tally important for making discoveries about their composition, layer structure, surfaces, and degra-‐ dation. It also provides information to address art historical and conservation questions, such as those related to the technology of fabrication, trade routes in antiquity, attribution, dating, and, most important of all, long-‐term preservation. But because cultural heritage objects are often hetero-‐ geneous and complex, the field demands new and improved approaches to this science of measure-‐ ment. In this way, cultural science is similar to cell biology, as both fields involve complex systems that will require massive leaps in our ability to make multiple measurements on varying time scales, across disparate length scales, and involv-‐ ing a wide range of chemical species, including or-‐ ganic and inorganic molecules with both high and low molecular weights.

But cultural heritage science is subject to sub-‐ stantial technical constraints that do not affect other fields, such as cell biology. Cultural heritage objects are irreplaceable, so analytical investiga-‐ tions must be noninvasive, or at least require only minimal sampling, and they must be rapid and highly sensitive. Tests to understand an object’s properties and monitor its performance need to be ing technologies, which can have broad applica-‐ tion. The constraints and complications of cultural heritage science provide a demanding proving ground for new analytical techniques and instru-‐ mentation. Other fields, such as the industrial, biomedical, and environmental realms, can clearly benefit from advances in the analytical techniques of cultural heritage science. In-‐line industrial qual-‐ ity-‐control processes; in situ analysis of aerospace components; pharmaceutical analysis; and in-‐field trace detection of narcotics, biowarfare agents, and biologically and environmentally active mole-‐

cules are just a few examples.

R ESEARCH T HEMES

Improving analytical technologies for use in cul-‐ tural heritage science involves expanding the abili-‐ ties of these tests to provide a suite of complex, detailed, and integrated information. The ultimate goal is to develop analyses that provide three-‐ dimensional data, can be specific at the molecular level, are highly sensitive, and operate at multiple spatial scales—macro, micro, and nano. And ide-‐ ally, the tests must work in situ and without the removal of precious samples from the artifacts or artworks. There are several complementary scien-‐ tific drivers for working toward these goals.

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Material and Structural Complexity – Up-‐ dated analytical technologies must be able to investigate heterogeneous materials that are structured in complex ways.

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Spatial Resolution – Ideal analytical tests should provide information on the scale of a whole artwork or structure, and at mi-‐ croscopic level and molecular resolution.

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Volume Restrictions – Sampling from cul-‐ tural heritage objects often is severely re-‐ stricted. However, some information

(isotope ratios, precise identification of or-‐


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ganic species, etc.) can only be obtained with destructive techniques. Borrowing from the biomedical field, in which tech-‐ niques are applied to extremely small vol-‐ umes, can benefit cultural heritage research.

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Remote Sensing – To use the least destruc-‐ tive or invasive tests possible, remote tests, which can be conducted without making any contact with the object, are ideal.

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Minimal Invasiveness – Those tests that require contact with an object or sample must be improved to decrease their impact

as much as possible.

A DVANCES N EEDED

The key advances that are urgently needed to im-‐ prove the characterization of the materials of cul-‐ tural heritage objects are the development of advanced analytical techniques that combine a va-‐ riety of tests on multiple scales, and a robust theo-‐ retical framework for interpreting the data they produce. Progress has been made in the creation and use of devices that chemists and materials sci-‐ entists can use to analyze microscopic samples or, in some cases, whole museum objects in situ

(without taking samples at all). Yet there remain limitations to these procedures in terms of their sensitivity and noninvasiveness, and in the ability of cultural heritage scientists to integrate these data to understand an entire object. Researchers need flexibility, and must be able to achieve comprehensiveness and minute detail at the same time.

For example, advanced analytical techniques are needed to be able to create large-‐scale, three-‐ dimensional maps of an entire object with mole-‐ cule-‐level detail. An ideal system could then com-‐ bine this topographical information with details of the molecular or elemental composition of any part of the piece. And these data could in turn be integrated with deep-‐penetrating imaging tech-‐ niques, such as optical coherence tomography, ul-‐ trasound imaging, terahertz imaging, or single-‐ sided nuclear magnetic resonance imaging. The same applies to samples from objects, such as the cross-‐sections sometimes taken from multilayered objects such as paintings. Researchers need to be able to perform depth profiling, imaging, molecu-‐ lar mapping, organic/inorganic analysis, and chemical speciation on a single sample in an effi-‐ cient and manageable way. The idea is to integrate analytical tests on multiple scales and looking at multiple attributes. Specific questions will drive how such suites of devices might be used. For ex-‐ ample, if a scientist wants to measure inorganic or polymer systems in an artist’s materials, then mi-‐ cron-‐scale tests will be sufficient. But if one is try-‐ ing to determine the geographical origin of a sample of lapis lazuli, then nanoscale resolution with high sensitivity for trace elements is crucial.

Also, as will be discussed in more detail in the other two Grand Challenge sections, real-‐time and time-‐dependent testing and chemical sensors also will be important to track deterioration, ultraslow

Fig. 3 – To identify the pigments used on this mummy’s shroud, City College of New York chemistry student Tat- yana Teslova subjected a minute sample to surface- enhanced Raman scattering and found the pink dye was madder lake. (Photos: The Metropolitan Museum of Art)


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processes, and transport within an artwork, such as solvent migration in a painting.

In addition to this broad need for advanced analytical techniques that will be specifically use-‐ ful to the study of cultural heritage objects, other, more targeted developments would also benefit this area of study. Analytical tests that require fur-‐ ther refinement include surface-‐sensitive tech-‐ niques, the ability to measure organic materials, in situ surface-‐enhanced Raman spectroscopy

(SERS), and the use of synchrotrons and other large-‐scale facilities.

Improved surface-‐sensitive techniques are necessary because the deterioration of objects of cultural heritage may involve changes in very thin layers of oxidation. Such tests could also be used to detect, at a molecular level, the interaction of the original object with environmental pollutants, ma-‐ terials used in their treatment or conservation, or electromagnetic radiation. This would allow the monitoring of the kinetics and molecular dynamics of reactions occurring directly on the surface of the object or at interfaces between different mate-‐ rials in it.

Another challenging area of research is the measurement of organic materials. The scientific study of cultural heritage objects would benefit greatly from the ability to conduct molecular fin-‐ gerprinting, and mapping and depth-‐profiling, of organic components either in situ or with minimal sampling. Improved signal amplification, hyphen-‐ ated techniques (that is, methods that combine several analytical approaches), and methods of derivatization can help achieve this. One of the methods for organic analysis, SERS, has enabled detection of microscopic amounts of biomolecules, such as natural colorants, in extremely aged mate-‐ rials, such as dyed textiles or faded watercolors.


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However, there is a real need to perform such highly sensitive analysis in situ, by bringing the probe to the artifact or sample without leaving residues, perhaps with tip-‐enhanced SERS (TERS) or SERS-‐active optical fibers.

In addition, over the past decade, large-‐scale facilities, such as synchrotron sources and centers for particle physics, have greatly advanced the ability to probe whole museum objects, though research is needed to accelerate acquisition times.

Also, recent advances in X-‐ray optics allow for ma-‐ terials analysis at finer and finer length scales. For example, in computed X-‐ray tomography, imaging with 10 X lenses provides submicron spatial infor-‐ mation, which can then be used to reconstruct three-‐dimensional images. Combinations of tech-‐ niques provide another route for their develop-‐ ment and further refinement. Coupling imaging with phase analysis provides a powerful, noninva-‐ sive method for studying microstructure and chemistry. Developments in zone-‐plate focusing optics, in conjunction with synchrotron X-‐ray sources, have enabled structural studies of nano-‐ size objects—an advance that has consequences in the study of the early stages of corrosion, the structure of nanoparticles that give rise to lusters, and the aggregation of nanoparticles in photo-‐

graphs. Ultimately, new or improved noninvasive and mobile instrumental methods need to be de-‐ veloped to avoid the need to transport irreplace-‐

able pieces of cultural heritage to these types of external facilities.

Achieving all of these ambitious advances— from new, integrated analytical tests to using par-‐ ticle physics labs—will require the development of theoretical and computational methods to create accurate predictive models for the behavior of cul-‐ tural heritage objects. We must have a robust baseline framework from which to design analyti-‐ cal tests, interpret findings, and attempt to predict the effects of age and treatment on these objects.

One critical example of this is the need to model the interaction of electromagnetic radiation with complex materials so we can understand their dielectric properties and predict how they will absorb energy on a molecular level. This will require a combination of experiment and theory.

We must prepare standard test materials with known properties, measure them, and encourage communication between labs to establish these standards. The same process applies to a number of other material characteristics that cultural heri-‐ tage scientists need to assess. Another example is better molecular computation to study excited states for interpreting spectral data, which can help predict how environmental factors and laser treatments might affect cultural heritage objects.

Please see Appendix A for additional recommenda-‐ tions from the workshop breakout sessions.


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G RAND C HALLENGE 2

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C ultural heritage objects, for all their intangi-‐ ble attributes, are still physical objects sub-‐ ject to a variety of internal and external processes that can break them down or alter their

Whitmore, Research Professor in the Department of Chemistry and Director of the Art Conservation

Research Center at Carnegie Mellon University, spoke to the attendees before they broke out into

“performance”—changing their aesthetic appear-‐ ance (such as fading of colors) or information con-‐ tent (such as loss of magnetization in tape recordings). The processes of deterioration are key to understanding how objects have aged and will age, and are critical to their survival as cul-‐ tural artifacts. Effective conservation strategies must be aimed at diagnosing the underlying causes of deterioration, identifying early stages of change, arresting the progress of those processes, and us-‐ ing safe and effective repairs that are not them-‐ selves prone to deterioration. The second of the workshop’s Grand Challenges dealt with under-‐ standing the dominant material degradation proc-‐ esses and the risk factors governing their rates.

Workshop Steering Committee member Paul discussion groups.

As with the development of analytical tech-‐ niques for the study of cultural heritage objects, understanding their deterioration is complex and multifactorial. Such artifacts are composed of an enormous variety of materials and structures, and are subject to a wide range of storage and display environments. Consequently the problems these objects face and their root causes are legion. Typi-‐ cally, the artifacts themselves dictate what will be studied. Changes in specific objects, or the results of those changes, attract research attention. In other cases, an object’s cultural importance, rather than specific observed changes, drive research. For example, objects such as the U.S. Charters of Free-‐ dom are so highly prized that extraordinary meas-‐ ures are sought to reduce all deterio-‐ ration to an abso-‐ lute minimum. The study of many deg-‐ radation phenom-‐ ena often requires specific foci, so the results often are not transferable to other object types.

Understanding material degrada-‐

Fig. 4 – Scientists at the Art Institute of Chicago conducted artificial aging tests of paint samples

(upper left) to determine how the zinc yellow used by French postimpressionist Georges Seurat in his A Sunday on La Grande Jatte – 1884 (1884–86) might have deteriorated over time under a variety of environmental conditions. (Photos: Art Institute of Chicago) tion usually re-‐ quires intensive study down to the microstructural and molecular levels.

This work focuses on understanding chemical reactions or physical changes, and measuring the rates of those proc-‐ esses and the fac-‐ tors, both within


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the object and outside of it, that affect them. Again, cultural heritage science faces the constraint of having irreplaceable objects as its subject. As a re-‐ sult, the study of deterioration can rarely be done on the cultural objects themselves. Instead, these studies must usually be translated to the labora-‐ tory, where idealized surrogate objects (close ap-‐ proximations of the authentic materials and structures) can be studied under controlled condi-‐ tions and to a greater level of detail. This process illustrates the degree to which all aspects of cul-‐ tural heritage science are linked—the information necessary to create such surrogates depends heav-‐ ily on the advanced analytical techniques dis-‐ cussed in Grand Challenge 1.

Laboratory study of cultural material degrada-‐ tion has both advantages and disadvantages. The main advantage is that in the lab, better, more in-‐ sightful, and highly controlled experiments can be done than with the cultural objects themselves.

Studies can be repeated to achieve statistical sig-‐ nificance, and the full range of analytical tools can be used, including destructive or less sensitive analytical techniques that require the consump-‐ tion of large amounts of sample material. However, these lab tests will be, in some sense, divorced from the original artifacts: the samples and the aging processes to which they are subject are only approximations. Authentic materials and struc-‐ tures in degraded states are difficult to re-‐create, and often samples are created to be “typical,” rather than specific to a unique artifact with a sin-‐ gular aging history. Similarly, very slow processes cannot be studied with precision—stress-‐testing or accelerated aging must stand in for centuries of wear and tear. As a result, the relevance of the laboratory simulations is unclear.

To examine this relevance, cultural heritage scientists must return to the cultural artifacts themselves. This “reality check” or “ground-‐ truthing” can be used to verify that the outcome of the laboratory tests resembles natural aging proc-‐ esses. By surveying groups of authentic objects, one can create benchmarks for lab studies, confirm predictions, and improve the surrogate objects and processes. This cycle of lab testing, compari-‐ son to actual object behavior, and refinement of lab tests is at the center of the study of degrada-‐ tion of artifacts.

These surveys of actual objects that share ma-‐ terials and aging histories can also be used outside the lab setting. Surveys can, for example, help cul-‐ tural heritage scientists explore the natural varia-‐ tion of materials, differences in manufacturing conditions, or the results of different storage and display histories. In some circumstances—an

Egyptian mummy, for instance—it is not feasible to re-‐create an authentic object, so insights into the properties, stability, and care must come from the object itself. The materials of many ancient ar-‐ tifacts can be so transformed by the millennia that one cannot estimate or infer their unique chemical or physical properties. It may be necessary to sac-‐ rifice a small portion of the materials or even a companion or duplicate object to gain the desired understanding. New developments, such as in-‐ creasingly sensitive analytical tools, are slowly ex-‐ panding the range of possible studies, so that now it is becoming more possible to study slow degra-‐ dation processes on artifacts themselves without

this sacrifice.


Research in the area of material degradation is motivated primarily by the need to diagnose fun-‐ damental deterioration problems affecting physi-‐ cal properties, appearance, and information content of cultural objects. There are several com-‐ plementary scientific drivers for working toward this goal.

•

Complex Materials – Many cultural heri-‐ tage objects are composed of complex ma-‐ terials and structures. Paintings, for example, are composite materials, while stone has a porous structure. Deterioration processes of complex structures must be further investigated.

•

Multiple Environmental Stressors – No en-‐ vironmental stressor, such as heat, humid-‐ ity, light, or pollutants, operates on an object in isolation. How do multiple stres-‐ sors affect an object’s degradation?

•

Ultraslow Processes – In “non-‐severe” en-‐ vironments (under room temperature, moderate humidity, and ultraviolet-‐free lighting), slow aging processes continue to take place. These difficult-‐to-‐simulate ef-‐ fects, and ways to limit their rates, must be understood in greater detail.

•

Relationship Between Processes and Per-‐ formance – Research effort must be in-‐ vested in understanding how chemical and


13

physical processes in cultural heritage ob-‐ jects correlate with the loss of performance properties (physical properties, appear-‐ ance, information content, and others).

A DVANCES N EEDED

Advances in several key areas will help cultural heritage scientists address the scientific drivers.

Specifically, analytical tools customized for assess-‐ ing processes (including ultraslow ones and envi-‐ ronmental monitoring) and greater understanding of molecular ordering, among other advances, will be necessary.

Progress in understanding material degrada-‐ tion processes is driven largely by advances in analytical technologies that are noninvasive and have high sensitivity and spatial resolution. In ad-‐ dition to the benefits of these tests described in the previous Grand Challenge summary, they can also be used to characterize the results of degradation processes and the basic materials of an artifact, so that accurate lab surrogates can be developed.


14

However, these tools have limits when applied to an object’s deterioration—they cannot, for exam-‐ ple, noninvasively probe a performance property such as physical strength. Such tests would be of great benefit in understanding how artifacts age and whether they are at risk. These analytical tests will still require high sensitivity, noninvasiveness, and spatial resolution across multiple scales. In addition, it is important that they be tailored, or new tests developed, to study important deteriora-‐ tion changes in artifacts. In some cases, tools de-‐ veloped for other uses might be insufficient in this context. For example, sometimes small chemical reactions can compromise performance. Polymers can completely lose strength when just 0.1 percent of the chemical bonds in the molecules change.

New techniques, such as mass spectroscopies that can probe very slight changes in high-‐molecular-‐ weight substances, or sensitive and spatially re-‐ solved optical spectroscopies, will enable better examination of the fundamental nature of deterio-‐ ration processes in the lab.

In addition to very slight degradation, these tests also must be refined and re-‐engineered to study ultraslow processes, which are taking place in every cultural heritage object all the time. These technologies can be used to monitor the environ-‐ ment surrounding objects, as well as the condition and stability of them, and will help correlate lab test results with authentic objects in real-‐world conditions. Some tools for this are available—for the spectroscopic characterization of color, for ex-‐ ample—yet the protocols for their use over many years (including correlating results from early generations of devices to later ones) must be de-‐ veloped.

At the level of basic science, a more complete description of deterioration requires study of the supramolecular order in the materials composing cultural artifacts. This high-‐level ordering of mole-‐ cules can control the rate of degradation and how it affects an object’s performance. For example,

Maya blue is a pigment containing the moderately stable indigo molecule, but as a whole is extremely stable because the indigo molecules are interca-‐ lated in the structure of the clay. Paper enjoys flexibility and cohesive strength from the ar-‐ rangement of cellulose molecules in microfibrils and fibers. Deterioration of paper is known to de-‐

rive from the breakdown of the cellulose chains, but how that reaction affects physical properties is poorly understood. Experimental studies, such as

X-‐ray scattering, that can elucidate molecular or-‐ dering will be essential.

Other deterioration processes that require fur-‐ ther study come from the complexity of specific artifact materials. Common damage, such as the rupture of stone from crystallization of incorpo-‐ rated salts, involves a simple molecular-‐scale change that occurs in a constrained environment in the pores of the mineral. That added complexity introduces new forces—the pushing of the grow-‐ ing salt crystals against the mineral surfaces causes the stone to fracture and crumble. Under-‐ standing these degradation processes requires both experimental study and theoretical modeling of the complex systems. And finally, research effort must be directed toward understanding what hap-‐ pens when multiple degradation processes take place at the same time—as they do in every object in the real world. Lab simulations of these multiple stressors will be needed to simulate more accu-‐ rately the interaction of various processes occur-‐ ring simultaneously, but at different rates and with different effects on performance.

Molecular modeling and multiscale simulation also are important for understanding an object’s chemical stability and material properties— indicators of the state of preservation at the mo-‐ lecular level. With a basic simulation of an object, scientists can test, with no risk to a real piece of cultural heritage, the effects of conservation and restoration interventions by modeling the chemi-‐ cal changes caused by treatment materials and ex-‐ trapolating the physical results. Computational models can also be used to compare natural aging with accelerated aging, or to observe how changes in temperature and humidity affect an object’s physical properties. For example, one can model the effects of deacidification or cold storage on cel-‐ lulose-‐based objects, such as watercolor paintings, photographs, or important documents. Or one can create a model to understand how areas of crystal-‐ linity might develop in natural and synthetic po-‐ lymeric materials, and whether they confer strength or weakness. Please see Appendix A for additional recommendations from the workshop breakout sessions.


15

G RAND C HALLENGE 3

M

ATERIALS

S

TABILIZATION

,

S

TRENGTHENING

,

M

ONITORING

,

AND

R

EPAIR

I n addition to learning more about the artifact or artwork itself, cultural heritage science is largely dedicated to improving the conserva-‐ tion and restoration of irreplaceable objects. Con-‐

Sometimes treatment materials fail to perform as predicted or cleaning strategies result in damage that is only obvious after months or years. De-‐ tailed, fundamental scientific investigations are servators need ever more sophisticated informa-‐ tion and tools to continue to ensure that cultural heritage will be available to future generations.

The findings of analytical tests and degradation studies can be applied to treatment, stabilization, and the study of the environment in which works are displayed or stored. As a result, this is a broad topic of discussion, encompassing everything dis-‐ cussed in the previous Grand Challenges and then applying those scientific advances in the conserva-‐ tion laboratory. Workshop Steering Committee member Barbara Berrie, Senior Conservation Sci-‐ entist at the National Gallery of Art in Washington,

D.C., spoke to the workshop attendees about the specific challenges of applying cultural heritage science to conservation.

There are two broad approaches in this area: assessing existing and potential treatments for cul-‐ tural objects, such as solvents and adhesives, and determining how environment—a suite of external factors that includes light, heat, pollution, and hu-‐ midity—affect the stability and longevity of those objects.

Like cultural heritage scientists, conservators face severe restrictions on the work they do to stabilize or repair cultural objects. Their methods must be reversible—that is, any repairs must be readily identified and removed or undone. Sam-‐ pling of objects must be minimal or nonexistent, and conservators must not alter the appearance of a work in unanticipated ways when they apply coatings, solvents, or consolidants. As a result, the methods for cleaning and preserving works of art have changed little in the last century. For exam-‐ ple, the use of organic solvents to remove varnish layers has been the most widely employed method since it was introduced in the nineteenth century.

But in some cases, the most well-‐intended treat-‐ ments can be ineffective or potentially damaging. needed to assess these treatments, determine why they did not work, and devise altogether new strategies.

In the case of varnish removal, for example, new techniques have begun to emerge, guided and refined in some cases by cultural heritage scien-‐

Fig. 5 –Marco Leona of The Metropolitan Museum of Art uses a handheld monitor to measure ultraviolet light levels affecting Oceanic art. (Photo: The Metropolitan Mu- seum of Art) tists. Gels, resin soaps, and lasers have been brought to the problem. Further refinements and new techniques often come from advances in sci-‐ entific research—either through increased under-‐ standing of the objects themselves or research dedicated to devising new treatments for them.

However, conservators, restorers, and curators usually turn to scientists for help on specific pro-‐ jects—the ones they are working on at the mo-‐ ment. Because of this, most scientifically developed solutions are driven empirically, by the needs of the moment, rather than theoretically.

The triage approach to problem solving will not advance the field of cultural heritage science and may impair the ability of cultural heritage scien-‐ tists to help conservators.


16

Cultural heritage objects are unique, heteroge-‐ neous, and complex, so a treatment strategy spe-‐ cifically designed for one may create serious problems when applied to another. Addressing this issue requires a rethinking of the manner in which new treatments are developed. Working from sound scientific principles and new research, scientists can help develop innovative ways to clean and stabilize objects and, using modeling, even anticipate the consequences of specific con-‐ servation treatments or storage or display condi-‐ tions. This would allow modifications and refinements to be made theoretically, shifting cur-‐ rent strategies for the treatment and care of cul-‐ tural heritage away from the pure empiricism.

There is a powerful need for cooperation and education regarding the scientific challenges of assessing old treatments and devising new ones— between conservators, curators, cultural heritage scientists, and scientists in other disciplines.


There are several areas in which increased under-‐ standing of physical and chemical processes will have a major impact on the treatment of our mate-‐ rial cultural heritage. Cultural heritage scientists and conservators can then use this basic informa-‐ tion to develop general strategies that are flexible enough to apply to unique objects with distinctive problems.

•

Dynamic Imaging and Sensors – Real-‐time chemical and spectroscopic imaging, and


17

ultrasensitive chemical sensors, can be used to monitor stability of an object, the effects of treatment, environmental condi-‐ tions, and molecules on the surface that signal unseen or subthreshold deteriora-‐ tion, perhaps related to a conservation treatment.

•

Solvents – A traditional technique for cleaning or restoring paintings, solvents can be improved, perhaps by incorporating them in new delivery mechanisms, such as ionic liquids, gels, or sols. Further study will include the effects of solvents on the metal-‐organic frameworks that are present in paint films and crusts on stones.

•

Reversible Adhesion – Conservators use a variety of adhesives to repair broken ob-‐ jects such as those made of glass, ceramic shards, fossils, and other materials, and improved adhesives will be both stable and completely reversible.

•

Transport Phenomena – Clarifying how components move in bulk through an ob-‐ ject will help cultural heritage scientists understand how they influence surface re-‐ actions that might affect performance or appearance.

•

Material Degradation Processes – A major goal of conservation is returning material strength to objects. Creating new and bet-‐ ter ways of doing this relies on the founda-‐ tional science of the processes of degradation—specifically those that cause fissure and crack formation, loss of tensile strength, embrittlement, and friability.

A DVANCES N EEDED

The advances necessary to improve the way that cultural heritage scientists and conservators work together to improve existing conservation treat-‐ ments and derive new ones center around a key shift in scientific approach—using theory and a fundamental understanding of materials and proc-‐ esses to drive innovation, rather than the empiri-‐ cal, triage approach that may create techniques with limited or unpredictable applicability. Rather than having conservators bring specific objects and problems to cultural heritage scientists, con-‐ servators and scientists can work together to bring scientific rigor and advances to the traditions of the practice of conservation.

An example of this approach comes from the study of material degradation processes and how they influence and initiate various breakdowns in an object’s stability. The new field of materiom-‐ ics—the study of the material properties of bio-‐ logical tissues or proteins and their effect on macroscopic function—provides a good model for how to relate properties, across a large scale range, to the function of complex composite mate-‐ rials, such as cultural heritage objects. It presents a means by which to apply, theoretically and scien-‐ tifically, the findings of materials science to the behavior of works of art and their treatment.

Another interesting angle on this idea is Mate-‐ rials by Design ® , a method, pioneered by G.B. Ol-‐ son of Northwestern University, of designing materials to meet multiple performance require-‐ ments. In cultural heritage science, this might mean creating a material with specific optical characteristics, mechanical robustness, and the ability to adhere reversibly to a cultural heritage object. The technique may replace the time-‐ consuming, trial-‐and-‐error, experimental method of developing new materials by integrating physi-‐ cal materials science, processing science, applied mechanics, quantum physics, mechanical engi-‐ neering, and solid-‐state chemistry. It requires a strong foundation in computational materials sci-‐ ence. The Materials by Design ® process begins with the identification of the performance re-‐ quirements, and then incorporates both structural properties and processing-‐structure relationships to meet them. Often the different properties re-‐ quired of the material, known as subsystems, in-‐ teract and conflict—for example, an adhesive with the right material strength may not look the way it needs to—so priorities have to be established to reach appropriate compromises. Currently, there are computational design tools for all the length scales needed for robust materials design and as-‐ sessment of thermodynamic stability. However, the process lacks a complete database of the pa-‐ rameters necessary for work on cultural heritage materials.

Understanding the environmental conditions that cause or exacerbate degradation, as well as the stability and effects of treatment, is another critical area in which cultural heritage scientists can provide direct support to conservators and curators. It is in this area that advancements in real-‐time, ongoing spectroscopic imaging can help


18

predict deterioration caused by pollutants by as-‐ sessing precisely how objects change under vary-‐ ing environmental conditions. Supplemented with mathematical modeling, this can be a powerful tool for understanding the basics of the breakdown of cultural objects and how conservation can arrest those processes—even when the effects of degra-‐ dation cannot be observed in other ways, also known as subthreshold changes.

Furthermore, better chemical imaging and monitoring, like the techniques discussed in the first Grand Chal-‐ lenge, which operate at micro-‐ and macro-‐ scales, with high resolution and a large field of view, are essential for the ongoing monitoring of treatments once they have been com-‐ pleted.

In addition to closely watching frameworks. Understanding this degradation process, the reactions that follow it, how solvents affect it, and how molecules move through an ob-‐ ject are critical to understanding why a painting or other object breaks down and how it can be cleaned safely.

For adhesion, key scientific advances must be made in the science of making adhesives that are both stable and reversible—that is, like all conser-‐ vation treatments, they must be able to be re-‐ moved completely from a piece, preventing the original from being permanently al-‐ tered. Innovations in this field could change the way conservators reas-‐ semble ceramic shards, fossils, and glass works, or how they reattach flakes of paint. And if enough options are made available, re-‐ treated and un-‐ treated objects, the science of the mate-‐ rials of cultural heri-‐ tage also can be used, with cooperation between disciplines, and between museums

Fig. 6 – Columbia University conservation scientist George Wheeler conducted extensive tests on sample blocks of marble to assess adhesives and a pinning system to repair a damaged, life-size sculpture. A scale model of the sculpture is visible at the lower right. (Photo: The

Metropolitan Museum of Art) and academic institutions, to improve the treat-‐ ments themselves. Two of the primary conserva-‐ tion interventions on works of art are cleaning, often using the same solvents and solutions that have been used for decades, and adhesion, used to reassemble broken objects or strengthen weak search into reversi-‐ ble adhesion also might lead to meth-‐ ods for temporarily stabilizing works for transport or ex-‐ hibition.

There are several other advances needed in the field of applying cultural heritage science directly to conservation treat-‐ ment. For example, materials scientists are study-‐ ing the chemical and physical factors that initiate and halt the aggregation of nanoparticles, which sometimes occurs when photographs, stained ones.

New delivery mechanisms for solvents, includ-‐ ing ionic liquids, gels, or sols, are one avenue of research. Another is understanding how solvents themselves affect the metal-‐organic frameworks in layers of paint—such as inorganic, metallic pig-‐ glass, or ceramic glazes are treated by conserva-‐ tors. Another topic that requires additional work is the understanding of the effects of the thin film of water—from the humidity in the air—that forms on the surface and in fissures of objects. Analysis of the reactions this water-‐film causes, and how ments with an organic binding agent—or as crusts on stone or ceramics that form as a result of bio-‐ logical activity. Degradation of these materials cre-‐ ates small molecules such as oxalic acid that migrate through objects—the same molecules that bond with metal ions to form metal-‐organic they are affected by conservation treatment, are ongoing. Ultrafine electrodes are one possible so-‐ lution that would be very useful in monitoring cor-‐ rosion. Please see Appendix A for additional recommendations from the workshop breakout sessions.


19

E

DUCATION AND

B

ROADER

I

MPACT

C ultural heritage science, by its very nature, builds bridges. As a field of scientific inquiry, it brings together chemistry, materials sci-‐ ence, and other specialized disciplines. But its ing and dissemination strategies, and overall benefits to society. As a single group, the work-‐ shop participants discussed these topics with re-‐ spect to cultural heritage science. practice reaches far beyond the scientific commu-‐ nity, across the aisle to archaeology, art conserva-‐ tion, art history, and the humanities. Cultural heritage science is not just at the interface be-‐ tween science and art—it is at their nexus.

Because of the connection of cultural heritage science with beloved works of art and intriguing bits of our shared past, the field broadens the ap-‐ peal of science as a whole, bringing science

E NHANCEMENT OF E DUCATION

Cultural heritage science advances discovery, in-‐ spires learning, and can reach populations that might not otherwise be exposed to science. Cul-‐ tural heritage research, when incorporated in high school and undergraduate chemistry curricula, engages students by showing tangible examples of how scientific inquiry can im-‐ pact our under-‐ to many people who might never come into contact with it, or may even ac-‐ tively distrust it.

Art and art con-‐ servation is a means by which to introduce students of every level to science and get them excited. In addition, cul-‐ standing of history, archae-‐ ology, and soci-‐ ety. In addition, the multidisci-‐ plinary nature of cultural heritage research en-‐ courages com-‐ plex problem solving and un-‐ derstanding of how theoretical models apply or do not apply to tural objects can bring science to the general

Fig. 7 – Northwestern University undergraduate Ariel Knowles and professor

Katherine Faber plan experiments using a plaster replica of a Shang Dynasty

(ca. 1600–ca. 1050

B

.

C

.) stone figurine. (Photo: Northwestern University) public in novel ways. Within the sciences, cultural heritage re-‐ search provides a means by which to encourage

“real-‐world” cases. At the graduate level, cultural heritage science courses are listed under both chemis-‐ try/materials science and art conservation, teach-‐ inter-‐ and multidisciplinary collaboration, and can drive innovation, in no small part because of the demands and constraints with which cultural heri-‐ tage scientists must contend. Finally, the inherent value of cultural heritage lends a criticality to this realm of scientific endeavor dedicated to its pres-‐ ervation and the knowledge about the past it can provide.

The NSF assesses the potential of proposed re-‐ search to provide broader impacts in four general areas: education, research and education infra-‐ structure, scientific and technological understand-‐ ing scholars at early stages in their careers the value of interaction across disciplines. Finally, at the postdoctoral level, the interdisciplinary nature of this research is ideal for cultivating research partnerships between academic and cultural insti-‐ tutions, and provides greater training opportuni-‐ ties for transferable skills.

The broad appeal of cultural heritage science also engages students who might not otherwise pursue careers in science. The enormous diversity of cultural heritage materials, for example, may appeal to students from a wide variety of ethnic,


20

geographic, and cultural backgrounds. Anecdotal evidence from conservation training, high school outreach, and intern programs indicates that stu-‐ dents who have been exposed to science through cultural heritage are likely to continue in science.

This effect, while intuitive, needs to be confirmed

and quantified.

E NHANCEMENT OF R ESEARCH AND E DUCATION

I NFRASTRUCTURE

Because of its interdisciplinary nature, cultural heritage science has tremendous potential to en-‐ hance facilities, instrumentation, and partnerships between researchers at different institutions. In particular, it brings together seemingly unrelated disciplines, such as the physical sciences, history, and art. The development of dedicated research centers would allow such partnerships to expand beyond the academic world to include researchers


21

from museums, national laboratories, and indus-‐ try. The instrumentation for the analysis of works of art preferably is noninvasive, nondestructive, portable, quick, and easy to use, meaning that it can have wide application. The development of regional mobile laboratories equipped with port-‐ able instrumentation would further enable diverse partnerships, making scientific resources available to smaller cultural heritage institutions through cooperative agreements.

E NHANCEMENT OF S CIENTIFIC AND T ECHNOLOGICAL

U NDERSTANDING

Compared to other scientific disciplines, cultural heritage research offers the opportunity to com-‐ municate its results through a wider range of me-‐ dia and approaches—to members of the scientific community, researchers in associated disciplines, and the general public. Publication of important findings in peer-‐reviewed scientific journals is of course important. It brings results directly to the scientific community and creates a research record for future inquiry. Web-‐based searches of the sci-‐ entific literature have greatly increased access to this information, but because cultural heritage re-‐ search also impacts the work of art historians, conservators, and curators, it is imperative also to present it at interdisciplinary conferences and symposia. Finally, through museums, galleries, and other cultural institutions, cultural heritage sci-‐

ence has access to a unique route to a broader audience. Scientists in this field can engage di-‐ rectly with the general public through gallery dis-‐ plays, exhibition publications, or public lectures.

These activities have the potential to introduce science to a large audience that is probably pri-‐ marily engaged with art, and thereby increase public awareness of the ways science can contrib-‐ ute to our understanding of the world and the past.

B ENEFITS TO S OCIETY

Cultural heritage research benefits society in many ways. At a basic level, by increasing knowledge of and helping to preserve our shared cultural heri-‐ tage, the field contributes to a critical need that impacts everyone—in ways both edifying and emotional. The study of the mechanisms of long-‐ term material degradation may provide new and more sustainable strategies for the exhibition, storage, and long-‐term care of cultural heritage materials. And the development of new techniques and materials can provide conservators with bet-‐ ter tools to preserve precious works of art for fu-‐ ture generations. At a scientific level, the development of new instrumentation that can per-‐ form analyses noninvasively, at high resolution and across multiple scales, can stimulate technol-‐ ogy transfer to related disciplines to benefit soci-‐ ety through improved industrial processes and other mechanisms. The investigation of historic materials also has the potential to increase our understanding of past cultures and societies, and perhaps reveal lost technologies that can provide insight into modern problems.


22

T

C

ULTURAL

H

ERITAGE

R

ESEARCH

F

UNDING IN

E

UROPE

here are considerable differences between the United States and Europe in the way that scientific research on cultural heritage is carried out. Here, most researchers in the field specialized centers. Much of the funding has come through the Environment Directorate of the Direc-‐ torate-‐General for Research, in addition to several programs under the European Cooperation in the are based in museums, libraries, or other institu-‐ tions dedicated to the conservation of cultural heritage. By contrast, in Europe, most researchers are based in academia. As a result, few museums in

Europe have their own scientific research labora-‐ tories. At the same time, substantial funding from the European Union has made this an attractive and sustainable field of inquiry for universities.

Since 1986, under the Framework Programme

1, the European Union has, through a variety of programs and mechanisms, provided considerable support to cultural heritage science, including re-‐ search infrastructure backing, research grants, human resources development, and the creation of

Field of Scientific and Technical Research Pro-‐ gramme (COST) . Founded in 1971, COST is an in-‐ tergovernmental framework that coordinates nationally funded research on a Europe-‐wide level.

In addition to the European Union programs, there are also limited funding opportunities at the na-‐ tional level in many countries, especially for equipment, PhD fellowships, and sometimes small national or bilateral projects. The European Com-‐ mission has set up an organization to coordinate the funding of these more distributed cultural heritage projects—the NET-‐HERITAGE European network on Research Programme applied to the

Protection of Tangible Cultural Heritage.

Fig. 8 – The CHARISMA mobile laboratory in Europe has made advanced analytical tools available to a wide range of cultural institutions that would otherwise not be able to conduct cultural heritage science. (Photo: Luca Sgamellotti)


23

Two cases provide strong examples of the strategies followed by the European Union: the series of cultural heritage research projects funded through the Environmental Technologies and Pol-‐ lution Prevention Unit of the Environment Direc-‐ torate (a division of the Directorate-‐General for

Research), and the various projects funded across

Europe after the first call for proposals of the

Framework Programme 7 (2007–13). In the latter case, particular attention will be paid to the

CHARISMA project, which resulted in the creation of a mobile analytical laboratory and a network to facilitate and coordinate access to large analytical resources across the continent.

From 1986 to 2006, under the Framework

Programmes 1 through 6, the European Union Di-‐ rectorate-‐General for Research sponsored, through its Environment Directorate, more than

120 separate projects involving 500 partners.

Most of the efforts under the first four Framework

Programmes, starting from the very first project,

Effects of Air Pollution on Historic Buildings (1986–

90), dealt with the impact of pollution on built heritage, though some subprojects addressed or-‐ ganic materials and development of new tech-‐ niques. Framework Programmes 5 and 6 expanded the scope of this supported research to include the impacts of environmental pollution, particulates, and global climate change on cultural heritage; the deterioration of indoor and outdoor cultural heri-‐ tage materials; the development of innovative, nondestructive analytical methods; the transfer of innovative technologies; and new conservation materials and methodologies.

The total expenditure for this expansion alone

(1998–2006) topped €50 million (over $70 mil-‐ lion). One project carried out during this period,

LightCheck ® , resulted in the successful develop-‐ ment and marketing of new disposable light indi-‐

cators for monitoring conditions in museums. The three-‐year project involved seven partners from five European Union countries and cost a total of

€1.5 million, (around $2 million).

The first call for proposals under Framework

Programme 7 saw 11 projects funded, involving

138 partners across the continent, for a total of

€30.2 million (over $40 million). These programs are structured around four thematic areas: Coop-‐ eration, Ideas, People, and Capacities. These areas support, respectively, transnational cooperation, investigator-‐driven “frontier research,” mobility of young researchers within Europe, and building and enhancing research capacity throughout

Europe. Cultural heritage projects were submitted and funded in all four thematic areas. A particu-‐ larly interesting one is Cultural Heritage Advanced

Research Infrastructures: Synergy for a Multidisci-‐ plinary Approach to conservation (CHARISMA), a project with 21 partners and €7.6 million (over

$10 million) in funding. CHARISMA represents the evolution of two other projects (totaling €4.2 mil-‐ lion, or over $6 million), LabSTECH and Eu-‐

ARTECH, funded in Framework Programmes 5 and

6, respectively. The goal of CHARISMA is to make advanced analytical equipment widely available to researchers at universities and cultural heritage laboratories. The result amounts to a transnational research center, spread across an infrastructure network for research on cultural heritage across Europe.

There are a number of ways in which the

European model of funding and cooperation might help guide the development of this discipline in the

United States, resulting in more funding, more ac-‐ cess to advanced equipment, and more interaction between cultural heritage institutions and univer-‐ sities. The NSF can play a central role in this process.


24

R

ESOURCES

N

EEDED FOR

A

DVANCING

C

HEMISTRY AND

M

ATERIALS

R

ESEARCH IN

C

ULTURAL

H

ERITAGE

A lthough the workshop focused primarily on the Grand Challenges and identifying major enabling research areas and specific re-‐ search needs in cultural heritage science, the final search is also needed to explore completely novel ideas and to nurture partnerships around common themes that require specialized expertise.

unified session of the workshop addressed the more general resources that will be necessary to encourage a quantum leap in the ability to study, understand, preserve, and protect cultural heri-‐ tage assets. The discussion was lively, and also spurred a spirited follow-‐up exchange on email among workshop participants, who identified the following themes as critical to this goal.

F LEXIBLE G RANT M ECHANISMS

Because of the interdisciplinary nature of the field, scientific research in cultural heritage hardly fits into a single box, such as chemistry, materials sci-‐ ence, archaeology, or art history. Therefore, it of-‐ ten has been difficult to find appropriate targets for research proposals in this area. Grant review-‐ ers and program officers must be aware of this complexity and offer flexible research grants that acknowledge the interdisciplinary nature of the field. This workshop and report are crucial early steps in this direction.

N EW C OLLABORATIVE A PPROACHES TO R ESEARCH

Grants should support three to five years of re-‐ search involving partners from academia, cultural institutions, national laboratories, and industry.

This type of sustained collaboration is the only way to advance the boundaries of scientific dis-‐ covery in this area, and will lead to the successful implementation of solutions for complex prob-‐ lems. In addition, seed funding for exploratory re-‐

D EVELOPMENT OF R ESEARCH I NFRASTRUCTURES

Instrument development grants will be necessary to advance all of the research areas highlighted in this report, from innovative methods of materials and structural characterization, to measurement of materials deterioration, to monitoring of strength-‐ ening and repair treatments. Instrument acquisi-‐ tion grants, which have historically been granted to museums and cultural institutions, will continue to be extremely important.

H UMAN R ESOURCES D EVELOPMENT

Human resources development and a creative ex-‐ change of ideas will be necessary, and can be achieved through the support of joint postdoctoral

fellowships, as well as international collaborations and exchanges of researchers.

C REATION OF C ENTERS OF E XCELLENCE

The workshop participants made a very strong call for the creation of specialized centers of excellence for cultural heritage science, ideally equipped with mobile laboratories. Such centers would be able to work at the leading edge of scientific discovery and foster cooperation and continuing exchange and engagement between academia, industry, na-‐ tional labs, and cultural heritage institutions. This could be achieved through workshops, web-‐based initiatives, focused symposia, and hosting of visit-‐ ing scholars and fellows.


25

C

ONCLUSIONS

C ultural heritage objects contain valuable in-‐ formation about both the art and science of the cultures that created them—knowledge that we can access and that tells us something

We believe this is the most critical result of the workshop: the creation of the core of a new re-‐ search community. The dialogues begun here must continue and the collaborations initiated at the about ourselves. Curiosity about our history spurs the scientific imagination and drives cultural heri-‐ tage science, including the development of new analysis methodologies and a deeper understand-‐ ing of materials properties. In this pursuit we chase more than scientific achievement; we chase a renewed appreciation of who we are and the debt we owe to artists and scientists of the past.

Scientific research inspired by the desire to learn more about our physical cultural heritage requires robust scientific thought and the development of state-‐of-‐the-‐art instrumental and analytical meth-‐ ods. Revealing the secrets of these precious arti-‐ facts and artworks while also learning how to preserve them demands innovative thinking.

The participants in this workshop—forty-‐two scientists from all areas of chemistry and materials science, representing colleges, universities, na-‐ tional laboratories, art museums, and cultural heritage institutions—agreed on the importance and urgency of scientific research on cultural heri-‐ tage. The challenges they explored offer consider-‐ able opportunities for fundamental research, promise to stimulate the development of new ma-‐ terials and advanced technologies, and can broaden and enliven the way science is taught. The participants engaged in a series of lively discus-‐ sions, exchanging ideas and insights and sowing the seeds of future collaborations. It is significant that every research idea discussed at the work-‐ shop was accompanied by the desire to establish a forum where scientists active in cultural heritage

research could meet their peers in academic insti-‐ tutions and involve them in their work.

workshop must be supported. To understand the lessons and messages of the scientific study of cul-‐ tural heritage, we need scientists who can place the findings in the appropriate context of the broad sweep of other fields. This is no easy task.

Disparate findings and results must be collated if we are to answer profound and important ques-‐ tions. Museum-‐based scientists often have strong empirical knowledge about the chemistry of com-‐ plicated chemical systems and are adept at obser-‐ vations related to surface chemistry, chemistry of composites, and changes in materials properties over time scales that are not familiar to bench chemists. Museum-‐based scientists also enjoy bet-‐ ter access to the history of science and art, which provides context to their findings. Scientists at universities, on the other hand, have access to more diverse suites of analytical equipment, apply theoretical underpinnings in their work, and are in a position to collaborate with scientists in other fields more easily.

Now is the time to merge these approaches and transform the traditional empirical approach of cultural heritage research into a deeper, branched, and layered field of inquiry, in which scientists in academia are encouraged to collabo-‐ rate with their peers in cultural heritage institu-‐ tions. Only in this manner can we successfully advance our understanding of cultural heritage and increase our ability to preserve it through ba-‐ sic and applied work in chemistry and materials science.


26

G RAND C HALLENGE 1

A PPENDIX A

A

DDITIONAL

R

ECOMMENDATIONS

F

ROM

B

REAKOUT

S

ESSIONS

In addition to the specific areas of optoelectronics and sensors, and x-‐ray optics/synchrotron techniques described in detail in Grand Challenge 1, there is a need to enhance our fundamental understanding of complex systems at the mo-‐ lecular level, both in static and dynamic conditions. Measurements of surface, subsurface, and bulk components and processes must be made over multiple time and length scales and concentrations. Specific research needs discussed by the workshop participants include:

• Development of probes based on below-‐breakdown threshold surface desorption to help detect loosely bound species in complex systems. Employing a focused laser beam (with energy below plasma threshold) and a mass “sniffer” will enable the detection of compounds evolved from the surface of an object. The advan-‐ tage of this approach, which involves photochemical bond-‐breaking with thermal energy ejection, is that it will allow deterioration monitoring and reactivity studies and offer characterization of the original compo-‐ nents, deterioration products, and species absorbed from environment without damage to an object.

•

Hyperspectral imaging in the visible, reflected near-‐ and mid-‐infrared (IR), and thermal IR to provide mate-‐ rial and structure information through molecular mapping at the large scale. By using standard spectra that can be processed to reduce the dataset and are compatible with existing databases, researchers will be able to achieve a comprehensive examination of an entire surface, highlighting common materials prior to point analysis.

•

Advances in large-‐scale atomic force microscopy (AFM) with enhanced Z range, by enlarging existing instru-‐ mentation and holding the scanning head over large areas. This would allow large objects with high topogra-‐ phy to be mapped, while simultaneously providing nanoscale information about structure and about deterioration processes that are either fully developed or only in incipient stages.

• Hyphenated techniques, such as Raman, terahertz, and nuclear magnetic resonance (NMR) spectroscopies.

Such strategies will provide chemical imaging and increased depth profiling over an entire object. Develop-‐ ment of other types of concurrent probes, such as modular microprobes employing spectroscopy and imaging with scanning arrays would extract chemical, structural, and elemental information from the same volume by enabling in situ multi-‐time-‐scale analysis with geospatial referencing capabilities. The portability and speed of noncontact analysis for this approach are highly desirable.

•

One-‐dimensional NMR, which would be able to map moisture movement in masonry by noninvasive profiling of very deep layers in situ

G RAND C HALLENGE 2

Research needs in the area of material degradation and aging were discussed at the workshop and include but are not limited to:

•

Deconvolution of simultaneously active mechanisms in deterioration processes by combining experimental and theoretical approaches. By using analytical chemistry to identify predominant mechanisms, in combina-‐ tion with cyclic and combinatorial approaches to experimental predictions, accompanied by theoretical mod-‐ eling, it will be possible to identify the predominant mechanisms and thus control accelerants.

• Contributions to the fundamental development of deterioration science

•

Development of a chip for rapid, real time, on-‐demand quantification of pollutants and environmental factors in macro-‐ and microenvironments (exhibition and storage spaces), both adventitious and coming from the work and their cases, to achieve better care of artwork

•

Development of a real-‐time laser-‐scanning spectroscopic techniques to detect distribution of pollutants in the environment around an art object, or off-‐gassed from exhibition, display, storage, packing materials, or the object itself, to obtain better awareness of the dynamics of the art-‐containing environment

• Improvement in the fundamental understanding of failure mechanisms, including both mechanical properties and chemical degradation of artworks, with special attention to the synergistic chemistries, such as exploring the evolution of components in an object over time. Through theoretical multiscale modeling, computational simulation, and experiments (including case studies and standards), the relationship between bulk, surface,


27

and synergistic effects and the environment during long-‐term degradation needs to be further explored, lead-‐ ing to the development of testable models and robust predictive capabilities.

•

Better understanding of the rate-‐determining processes in the surface interaction between objects (outdoor works and monuments) and the environment, so as to learn to mitigate them. Development of model sys-‐ tems/surrogates, derived from theoretical modeling to delay sampling, to relate to samples obtained from cultural heritage

• Development of a broad understanding of how study probes and treatments affect objects of cultural heritage through a combination of theory and experiment, to arrive at true nondestructive techniques and new stan-‐ dards for conservation of cultural heritage assets

• Characterization, with high sensitivity, of surface oxidation reactions for inorganic/organic composites

•

Development of an advanced, molecular-‐level understanding of transport phenomena of deterioration prod-‐ ucts, in conjunction with the detailed characterization of amorphous reactants and products. This may be achieved by using surface based-‐techniques (photoelectron spectroscopy, auger, photoluminescence, and others) on aged artworks and through the synthesis of model systems with the addition of organics. This ap-‐ proach would lead to the identification of vulnerable systems, and more focused and effective recommenda-‐ tions for display and preventive conservation, with wide applicability to systems within the field of cultural heritage science, but also high performance organic/inorganic composites and quantum dots, which are often dispersed in an organic matrix.

• Advancement of our fundamental understanding of the interfacial interaction between growing crystals and confining surfaces as observed, for example, with salt or ice in stone. An approach to addressing this need may involve atomic force measurements (AFM, macroscopic methods) and a combination of modeling (mo-‐ lecular dynamics) and modification of the stone‘s porosity with surface treatments. This will in turn allow a greater understanding of the nature of disjoining forces; the behavior of liquids in thin films; and the stresses in pores of stone, brick, and mortars, as well as the development of methods for protecting stone from salt and ice. Such important advances will lead to improved preventive treatments and permit the evaluation of risk of damage to original or repair materials.

G RAND C HALLENGE 3

Breakout session recommendations concerning materials stabilization, strengthening, monitoring, and repair include:

•

Improved quantitative monitoring of objects during cleaning, treatment, and storage. By measuring phenom-‐ ena such as polymer swelling during solvent cleaning, dimensional changes associated with temperature and

RH fluctuations during storage, and general chemical challenges, the evolution of objects can be followed ac-‐ curately, and true measures of conservation approaches obtained.

•

Targeted delivery of solvents and reagents. The use of encapsulated reagents, nanoemulsions, and procedures such as surface-‐energy-‐driven solvent intake (a process in which localized pressure can increase the solvent uptake at a determined location) would enable nano-‐ and microscale control of reactions. The approach would lead to improved treatment of complex objects though a better understanding of chemical and physical variables in cleaning and consolidation processes.

•

Developing new conservation materials as more stable replacements for traditional materials. One of the ma-‐ jor challenges in introducing new materials in the conservator’s toolbox is the reluctance to abandon materi-‐ als whose handling properties are well known and highly appreciated. Much has been done to identify suitable substitutions for picture varnishes. However, the development of new synthetic materials to substi-‐ tute for traditional consolidants and adhesives must include detailed studies of their viscoelastic properties.

The design phase should describe and quantify what constitutes desirable handling and characteristics, and investigate the relations between handling characteristics and other properties such as cohesive strength and thermal and light stability.

•

In parallel with the development of new varnishing, retouching, and consolidation materials, the use of new cleaning agents such as ionic liquids, gels, sols, and supercritical CO

2

should be investigated. Their use not only could lead to tunable and scalable cleaning approaches, but also would advance the development of green conservation methods.

•

Investigation and quantification of the concept of reversibility. A two-‐pronged approach featuring computa-‐ tional modeling of cleaning and consolidation procedures and the comparison—through extensive analytical investigations—of successful and less satisfactory treatments would allow clear definition of the operational parameters in conservation. An additional check would be provided by the rare cases in which objects come down with little or no intervention. The approach would provide a true scientific approach for cleaning methods.


28

•

Monitoring of subthreshold events. The use of surface characterization techniques, such as light scattering, in-‐ terferometry, ellipsometry, and imaging ellipsometry would allow the detection of microscopic changes in an object, delivering a digital health care record for an object. A particular case is that of cracks and craquelure.

Currently, these are only investigated when at an advanced stage. A “measurement and monitoring” approach would enable conservators to evaluate the state and progress of object under strain. Modeling the strain field should allow the determination of the environmental conditions leading to slower cracks and craquelure de-‐ velopment. Investigating rheology and tackiness can help determine the right amount of interaction in a sys-‐ tem. Studying direction and growth of crack systems would allow the diagnosis of the evolution of the system and help limit its progress toward failure. Another way to monitor subthreshold events is to understand the effects of incipient chemical reactions. These can be investigated in minute fissures on all substrates using ul-‐ tramicroelectrochemistry. Certain reactions may be discovered to be bellwethers for initiation of bulk chemi-‐ cal processes and material degradation.

•

Development of conservation materials with designed functionality, such as appearance, adhesion, perme-‐ ability, thermal match, wear resistance, and sustainability. By computational materials design and modifica-‐ tion of existing molecules, new conservation materials with the desired characteristics can be obtained. The approach would allow the development of a toolbox of materials for conservation uses.

• Development of protective coatings for monuments and outdoor sculpture. The coatings should be acid, frost, salt, and soil resistant, and photochemically stable. A possible approach to the development of coatings for stone, clay, adobe, or concrete monuments and sculpture is the study of water-‐permeable synthetic analogues of mineral phases. The ideal coating should be compatible with the stone characteristics, invisible, and offer adequate protection from environmental damage.

• Differentiation and evaluation of different factors in the performance of adhesives. A particular case is differ-‐ entiating mechanical and chemical interaction in adhesives for mineral structures. This is a fundamental step in evaluating materials for stone consolidation in art and architectural settings. The challenge would require modeling adhesion for high-‐surface-‐area, porous materials. The use of surface techniques such as secondary ion mass spectrometry can measure the energy necessary to remove molecules from mineral surfaces and characterize performance at the microscale.

•

Development of improved strategies for the treatment of delicate substrates. A particular case is that of laser cleaning: the use of femtosecond lasers coupled to surface-‐sensitive real-‐time analytical instrumentation can deliver significant improvements over current (mechanical and chemical) approaches, as ultrafast lasers eliminate thermal damage.


29

C O -C HAIRS

Marco Leona

The Metropolitan Museum of Art

Department of Scientific Research

1000 Fifth Avenue

New York, NY 10028

Phone: 212-‐396-‐5476

Fax: 212-‐396-‐5466 marco.leona@metmuseum.org

A PPENDIX B

W

ORKSHOP

P

ARTICIPANTS

Richard Van Duyne


Chemistry Department

2145 Sheridan Rd.

Evanston, IL 60208-‐3113

Phone: 847-‐491-‐3516

Fax: 847-‐491-‐7713 vanduyne@northwestern.edu

S TEERING C OMMITTEE

Barbara Berrie


Scientific Research Department

Sixth and Constitution Avenue NW

Washington, DC 20565

Phone: 202-‐842-‐6448

Fax: 202-‐6886

b-‐berrie@nga.gov

Francesca Casadio

The Art Institute of Chicago


111 South Michigan Avenue

Chicago, IL 60603-‐6110

Phone: 312-‐857-‐7647

Fax: 312-‐541-‐1959 fcasadio@artic.edu

Richard R. Ernst

ETH Zürich

Laboratorium für Physikalische Chemie

Wolfgang-‐Pauli-‐Str. 10

8093 Zürich, Switzerland

Phone: +41 44 632 43 64

Fax: +41 44 632 12 57

Richard.Ernst@nmr.phys.chem.ethz.ch

Katherine T. Faber




2220 Campus Drive

Evanston, IL 60208

Phone: 847-‐491-‐2444 k-‐faber@northwestern.edu

Antonio Sgamellotti

Università degli Studi di Perugia

Dipartimento di Chimica

Via Elce di Sotto, 8

06123 Perugia, Italy

Phone: +39 075 585 5504

Fax: +39 075 585 5624 sgam@thch.unipg.it

Karen Trentelman

The Getty Conservation Institute

1200 Getty Center Drive, Suite 700

Los Angeles, CA 90049

Phone: 310-‐440-‐6262

KTrentelman@getty.edu

Paul Whitmore

Carnegie Mellon University

Art Conservation Research Center

700 Technology Drive

Pittsburgh, PA 15219

Phone: 412-‐268-‐6854

Fax: 412-‐268-‐1782 pw1j@andrew.cmu.edu


30

P ARTICIPANTS

Ruth Ann Armitage

Eastern Michigan University


Ypsilanti, MI 48197

Phone: 734-‐487-‐0290 rarmitage@emich.edu

Christa Brosseau

Chemistry Department

2145 Sheridan Rd.


Phone: 847-‐467-‐6970

Fax: 847-‐491-‐7713 c-‐brosseau@northwestern.edu

John Delaney





Phone: 202-‐842-‐6708

Fax: 202-‐6886

j-‐delaney@nga.gov

J. Thomas Dickinson

Washington State University

Department of Physics and Astronomy

PO Box 642814

Pullman WA 99164-‐2814

Phone: 509-‐335-‐4914

Fax: 509-‐335-‐7816 jtd@wsu.edu

David Dillard

Virginia Tech

Department of Engineering

Science and Mechanics

219 A Norris Hall, MC: 0219

Blacksburg. VA 24061

Phone: 540-‐231-‐4714

Fax: 540-‐231-‐4574

dillard@vt.edu

Carl Dirk

University of Texas at El Paso


Materials Science and Engineering Program

500 W. University Ave.

El Paso, TX 79968-‐0513

Phone: 915-‐747-‐7560

Fax: 915-‐747-‐5748

cdirk@utep.edu


Vicky Grassian

University of Iowa


305 Chemistry Bldg.

Iowa City IA 52242-‐1294

Phone: 319-‐335-‐1392

vicki-‐grassian@uiowa.edu

Gene S. Hall

Rutgers University

Chemistry and Chemical Biology Department

10 Taylor Road

Piscataway, NJ 08854

Phone: 732-‐445-‐2590

Fax: 732-‐445-‐5312

hall@rutchem.rutgers.edu gene@genehall.com

Eric Hansen

Library of Congress

Preservation Research and Testing Division

101 Independence Ave. SE

Washington, DC 20540-‐4560

Phone: 202-‐707-‐1028

Fax: 202-‐707-‐1525

ehan@loc.gov

Kenza Kahrim

Università degli Studi di Perugia

Dipartimento di Chimica

Via Elce di Sotto, 8

06123 Perugia, Italy

Phone: +39 075 585 5504

Fax: +39 075 585 5624 kenzakahrim@hotmail.com

Ioanna Kakoulli

University of California, Los Angeles

Cotson Institute of Archeology

A410 Fowler Building

Los Angeles, CA 90095-‐1510

Phone: 310-‐794-‐4915

Fax: 310-‐206-‐4723 kakoulli@ucla.edu

Narayan Khandekar

Harvard University Art Museum

Straus Center for Conservation

485 Broadway

Cambridge, MA 02138

Phone: 617-‐495-‐4591

Narayan_khandekar@harvard.edu

31

Tami Lasseter Clare

Portland State University

Assistant Professor of Chemistry

PO Box 751

Portland, OR 97207

Phone: 503-‐725-‐2887

claret@pdx.edu

John Lombardi

City University of New York – City College


138th Street at Convent Avenue

New York, NY 10031

Phone: 212-‐650-‐6032

Fax: 212-‐650-‐6848 lombardi@sci.ccny.cuny.edu

Christopher Maines





Phone: 202-‐842-‐6055 fax: 202-‐842-‐6886 c-‐maines@nga.gov

Jennifer Mass

Winterthur Museum and Country Estate

Scientific Research and Analysis Laboratory

Route 52

Winterthur, DE 19735

Phone: 302-‐888-‐4808

Fax: 302-‐888-‐4838 jmass@winterthur.org

Blythe McCarthy

Smithsonian Institution

Freer Gallery of Art and the

Arthur M. Sackler Gallery

PO Box 37021, MRC 707


Phone: 202-‐633-‐0372

Fax: 202-‐633-‐9474

MccarBl@si.edu

Chris McGlinchey

The Museum of Modern Art


11 West 53rd Street

New York, NY 10019

Phone: 212-‐708-‐9821

Fax: 212-‐408-‐6425

Chris_mcglinchey@moma.org


Apurva Mehta

Stanford University

Stanford Linear Accelerator

2575 Sand Hall Road, Mailstop 0069

Menlo Park, CA 94025 mehta@SLAC.Stanford.edu

Gary Messing

Pennsylvania State University



121 Steidle Bldg.

University Park, PA 16802

Phone: 814-‐865-‐2262 messing@ems.psu.edu

Royce Murray

University of North Carolina at Chapel Hill


Campus Box 3290

Chapel Hill, NC 27599-‐3290

Phone: 919-‐962-‐6296

Fax: 919-‐962-‐2388

rwm@email.unc.edu

Dale Newbury

National institute of Standards and Technology

100 Bureau Drive, Stop 1070

Gaithersburg, MD 20899-‐1070

Phone: 301-‐975-‐3921

dale.newbury@nist.gov

Samir S. Patel

Senior Editor

Archaeology Magazine

36-‐36 33 rd Street, Ste. 301

Long Island City, NY 11106

Phone: 718-‐472-‐3050 x17 samir@archaeology.org

Hannelore Roemich

New York University Institute of Fine Arts

1 East 78th Street

New York, NY 10075

Phone: 212-‐992-‐5890

Fax: 212-‐992-‐5851

Hr34@nyu.edu

George Schatz



2145 Sheridan Road


Phone: 847-‐491-‐5657

schatz@chem.northwestern.edu

32

George Scherer

Princeton University

Chemical Engineering Department

Eng. Quad. E-‐319

Princeton, NJ 08544 USA

Phone: 609-‐258-‐5680

scherer@princeton.edu

Maurizio Seracini

University of California, San Diego

Center for Interdisciplinary Science for Art,

Architecture and Archaeology

9500 Gilman Drive #0436

La Jolla, CA 92093-‐0436

Phone: 858-‐534-‐7034 mseracini@ucsd.edu

D. Peter Siddons

Brookhaven National Laboratory

National Synchrotron Light Source

75 Brookhaven Avenue

Bldg 535, Room A-‐130

Upton, NY 11973-‐5000

Phone: 631-‐344-‐2738 siddons@bnl.gov

Mary Striegel

National Center for Preservation

Training and Technology

645 University Parkway

Natchitoches, LA 71457

Phone: 318-‐356-‐7444 x256

Fax: 318-‐356-‐9119 striegelm@nsula.edu

Tom Tague

Bruker Optics Inc.

19 Fortune Drive

Manning Park

Billerica, MA 01821–3991

Phone: 978-‐439-‐9899 x5110

tjt@brukeroptics.com

Pamela Vandiver

University of Arizona



1133 E. James E Rogers Way

Tucson, AZ 85721

Phone: 520-‐400-‐2270 vandiver@mse.arizona.edu

Richard Weiss

Georgetown University


37th and O Streets NW


Phone: 202-‐687-‐6013

Fax: 202-‐687-‐6209 weissr@georgetown.edu

George Wheeler

Columbia University

Graduate School of Architecture Planning &

Preservation

Historic Preservation Program

1172 Amsterdam Avenue

New York, NY 10027

Phone: 212 854 3973

Gw2130@columbia.edu

Y. Lawrence Yao

Columbia University

Mechanical Engineering Department

248 S. W. Mudd, Mail Code: 4703

New York, NY 10027

Phone: 212-‐854-‐2887

Fax: 212-‐854-‐3304 yly1@columbia.edu


33

A PPENDIX C

W

ORKSHOP

S

CHEDULE

M ONDAY , J ULY 6, 2009

Freer Gallery of Art and Arthur M. Sackler Gallery, Meyer Auditorium,

Smithsonian Institution, Washington, D.C.

6:15–6:30 pm Welcome and Opening Remarks

Julian Raby , Director, Freer Gallery of Art and Arthur M. Sackler Gallery Smith-‐ sonian Institution

Arden L. Bement Jr.

, Director, National Science Foundation

Angelica Zander Rudenstine , Program Officer, Museums and Art Conservation,

Andrew W. Mellon Foundation

6:30–7:00 pm Keynote Address: At the Interface between Science and Art

Richard Ernst , Professor Emeritus of Physical Chemistry, Eidgenössische Techni-‐ sche Hochschule (ETH), Zürich

7:00–7:30 pm Cultural Heritage Science

Marco Leona , David H. Koch Scientist in Charge, The Metropolitan Museum of Art

7:30 pm

T UESDAY , J ULY 7, 2009

Reception, Courtyard

Gallery 1 Meeting Room, Hilton Hotel, Arlington, Virginia

8:00–8:30 am Breakfast

8:30–9:00 am Introduction to the workshop and presentation of Grand Challenges (

Faber , Northwestern University)

Katherine T.

9:00–10:00 am Introduction to Grand Challenge 1 ( Francesca Casadio , Art Institute of Chicago):

Materials and Structural Characterization of Cultural Heritage (followed immedi-‐ ately by breakout sessions)

10:00–10:30 am

10:30–10:45 am

10:45–11:45 am

Presentation of Grand Challenge 1 quadrant slides

Coffee break

Introduction to Grand Challenge 2 ( Paul Whitmore , Carnegie Mellon University):

Understanding Material Degradation and Aging (followed immediately by breakout sessions)

11:45 am–12:15 pm Presentation of Grand Challenge 2 quadrant slides


34

12:15–1:45 pm

1:45–2:45 pm

2:45–3:15 pm

3:15–3:30 pm

3:30–4:30 pm

4:30–5:30 pm

Box lunch and presentation: The European Experience ( Hannelore Roemich ,

New York University Institute of Fine Arts, and Antonio Sgamellotti , Università de-‐ gli Studi di Perugia)

Introduction to Grand Challenge 3 ( Barbara Berrie , National Gallery of Art): Mate-‐ rials Stabilization, Strengthening, Monitoring, and Repair (followed immediately by breakout sessions)

Presentation of Grand Challenge 3 quadrant slides

Coffee break

General Discussion: Scientific research in cultural heritage and its impact on science, education, and society

General Discussion: The Grand Challenges


35