What is the meaning of “Nano” in Nanotechnology? Measurement “Weights and measures may be ranked among the necessaries of life to every individual of human society.” - John Quincy Adams, 1821 The International System of Units (SI) or Metric System • Provides a logical and interconnected framework for all measurements in science, industry, and commerce. • The unit of length in the metric system is the meter (m) – The meter was originally described as the a portion of the earth’s circumference. – Today the meter is described as the length of the path traveled by light in a vacuum during 1/299,792,458 of a second. – Measures for volume (liter) and mass (gram) are derived from the unit of length, thus relating basic units of the system to each other. The Metric System is a Decimal Based System • Units for a given quantity, such as length or mass, are related by factors of 10 and are expressed in a decimal system. • Prefixes, added to a unit name, create larger or smaller units by factors that are powers of 10. • Calculations involve moving the decimal point to the right or the left. Common Metric Prefixes • If you move to the right on the following chart, the decimal moves to the right. If you move to the left, the decimal moves to the left. • The bottom row shows 7 ways to express the distance of 1 meter. Factor 103 102 101 100 10-1 10-2 10-3 Common prefix kilo hecto deca meter, liter, or gram deci centi milli 0.001 0.01 0.1 1. 10. 100. 1000. Use the following metric prefixes when measuring very small quantities milli = 10-3 or 0.001 micro = 10-6 or 0.000 001 nano = 10-9 or 0.000 000 001 pico = 10-12 or 0.000 000 000 001 • Therefore 1 nanometer is one billionth of a meter or 1 meter is made up of a billion nanometers Use the following metric prefixes when measuring very large quantities kilo = 103 or 1,000 mega = 106 or 1,000,000 giga = 109 or 1,000,000,000 tera = 1012 or 1,000,000,000,000 Natural Phenomena Occur on Many Scales • Some phenomena are so small magnifying glasses or microscopes are used to view them. Others are so far away, powerful telescopes must be used. • We will start with a 109 meter viewing area and move to a 10-9 viewing area. • In each of the following pictures, the distance is measured from the left side to the right side of the picture. • The red box in the center of each picture represents the next scaled image (power of 10) to be shown. 109 meters or 1,000,000,000 meters This is the moon’s orbit around the Earth. 108 meters or 100,000,000 meters 107 meters or 10,000,000 meters 106 meters or 1,000,000 meters 105 meters or 100,000 meters Mountain range on the border of Switzerland and France. 104 meters or 10,000 meters Suburbs of Geneva on the Franco-Swiss border. 103 meters or 1,000 meters CERN facility (European Organization for Nuclear Research) on the Franco-Swiss border. 102 meters or 100 meters CERN facility. 101 meters or 10 meters Landscaping at CERN facility. 100 meter or 1 meter 10-1 meter or 0.1 meter 10-2 meter or 0.01 meter 10-3 meter or 0.001 meter A fly’s eye is made of many facets, resembling a honeycomb. 10-4 meter or 0.0001 meter A fly’s eye is made up hundreds of facets. Each facet has a lens with light sensitive cells underneath. This image was taken with an electron Microscope. 10-5 meter or 0.00001 meter In between the facets are bristles which give sensory input from the surface of the eye. 10-6 meter or 0.000001 meter The bristles are shown to be fluted. 10-7 meter or 0.0000001 meter Even more detail is shown of the bristle’s surface. 10-8 meter or 0.00000001 meter At the center of the cell is a tightly coiled molecule called DNA containing the genetic material needed to duplicate the fly. 10-9 meter or 0.000000001 meter DNA nucleotide building blocks. So what is Nanotechnology? • It is the understanding and control of matter at dimensions between 1 and 100 nanometers (billionths of a meter) where unique phenomena enable novel applications. – A nanometer is smaller than the wavelength of visible light and one hundred thousandth the width of a human hair! • It allows us to engineer functional materials, systems, and devices at the molecular scale.