nanoanalysisNanoanalysis refers to techniques for determining the atomic structures of materials, especially crystals. The technology is similar to that used for microanalysis, except it is done on a nanometer scale. (One nanometer is 10 -9 meter, or a millionth of a millimeter.) With any instrument used for nanoanalysis, there is a limit to the resolution (the diameter of the smallest object that can be resolved). This is true when the instrument works directly with electromagnetic radiation such as infrared (IR), ultraviolet (UV), visible light, or X rays, and also when the instrument employs high-speed subatomic particles such as electrons or ions. There is a minimum wavelength associated with any medium of observation. Objects whose diameters are less than this wavelength defy observation. In general, as the wavelength becomes shorter, the required particle or wave energy increases. This motivates scientists involved with nanoanalysis to seek ever-more-powerful machines with which to observe samples. The electron microscope is commonly used for nanoanalysis. There are two basic types that lend themselves to this application: the scanning electron microscope (SEM) and the high-voltage transmission analytical electron microscope. Also useful in nanoanalysis are X-ray and UV diffraction, IR microscopy, mass spectrometry, ion-beam machines, and precision optical microprobes.
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| Last updated on:
Sep 21, 2005 |
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WORD OF THE DAY... |
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netbook
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