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Instruments microscopy

Davies, R. "Laboratory Instrumentation Microscopy Pollution Analysis", Series II, Vol. Ill, Microscopy - Pollution Analysis, International Scientific Comm., 1977 p. 100-120B. [Pg.397]

AFM measures the spatial distribution of the forces between an ultrafme tip and the sample. This distribution of these forces is also highly correlated with the atomic structure. STM is able to image many semiconductor and metal surfaces with atomic resolution. AFM is necessary for insulating materials, however, as electron conduction is required for STM in order to achieve tiumelling. Note that there are many modes of operation for these instruments, and many variations in use. In addition, there are other types of scaiming probe microscopies under development. [Pg.310]

In addition to covering Raman microscopy, this book has a wealth of information on Raman instrumentation in general. Elving P J and Winefordner J D (eds) 1986 Fourier Transform Infrared Spectroscopy (New York Wiley)... [Pg.1178]

A completely new method of determining siufaces arises from the enormous developments in electron microscopy. In contrast to the above-mentioned methods where the surfaces were calculated, molecular surfaces can be determined experimentally through new technologies such as electron cryomicroscopy [188]. Here, the molecular surface is limited by the resolution of the experimental instruments. Current methods can reach resolutions down to about 10 A, which allows the visualization of protein structures and secondary structure elements [189]. The advantage of this method is that it can be apphed to derive molecular structures of maaomolecules in the native state. [Pg.129]

Typically, no with specialized instruments (e.g., low-energy electron microscopy), 150 A... [Pg.20]

If elemental or compound data are required, the material needs to be mounted for the appropriate analytical instrument. For example, if light microscopy shows a... [Pg.62]

The classical polarizing light microscope as developed 150 years ago is still the most versatile, least expensive analytical instrument in the hands of an experienced microscopist. Its limitations in terms of resolving power, depth of field, and contrast have been reduced in the last decade, in which we have witnessed a revolution in its evolution. Video microscopy has increased contrast electronically, and thereby revealed structures never before seen. With computer enhancement, unheard of resolutions are possible. There are daily developments in the X-ray, holographic, acoustic, confocal laser scanning, and scanning tunneling micro-... [Pg.68]

John C. Russ. Computer Assisted Microscopy. Plenum Press, New York, 1990. A highly readable account of the applications of computers to SEMs and other imaging instruments. [Pg.84]

The STEM instrument itself can produce highly focused high-intensity beams down to 2 A if a field-emission source is used. Such an instrument provides a higher spatial resolution compositional analysis than any other widely used technique, but to capitalize on this requires very thin samples, as stated above. EELS and EDS are the two composition techniques usually found on a STEM, but CL, and even AES are sometimes incorporated. In addition simultaneous crystallographic information can be provided by diffraction, as in the TEM, but with 100 times better spatial resolution. The combination of diffraction techniques and analysis techniques in a TEM or STEM is termed Analytical Electron Microscopy, AEM. A well-equipped analytical TEM or STEM costs well over 1,000,000. [Pg.119]

Cathodoluminescence (CL), i.e., the emission of light as the result of electron-beam bombardment, was first reported in the middle of the nineteenth century in experiments in evacuated glass tubes. The tubes were found to emit light when an electron beam (cathode ray) struck the glass, and subsequendy this phenomenon led to the discovery of the electron. Currendy, cathodoluminescence is widely used in cathode-ray tube-based (CRT) instruments (e.g., oscilloscopes, television and computer terminals) and in electron microscope fluorescent screens. With the developments of electron microscopy techniques (see the articles on SEM, STEM and TEM) in the last several decades, CL microscopy and spectroscopy have emerged as powerfirl tools for the microcharacterization of the electronic propenies of luminescent materials, attaining spatial resolutions on the order of 1 pm and less. Major applications of CL analysis techniques include ... [Pg.149]

D. B. Williams. Practical Analytical Electron Microscopy in Materials Science. Philips Electronic Instruments, Mahwah, NJ, 1984. Concise textbook on CBED, EDS, and EELS with a pronounced how-to flavor. [Pg.173]

S. J. Pennycook. EMSA Bulletin. 19, 67, 1989. A summary of compositional imaging using a high-angle annular dark-field detector in a field emission STEM instrument published by the Electron Microscopy Society of America, Box EMSA Woods Hole, MA 02543. [Pg.174]

The techniques, instrumentation and underlying theory of optical microscopy for materials scientists have been well surveyed by Telle and Petzow (1992). One of the last published surveys including metallographic techniques of all kinds, optical and electronic microscopy and also techniques such as microhardness testing, was a fine book by Phillips (1971). [Pg.217]

The impact of electron-optical instruments in materials science has been so extreme in recent years that optical microscopy is seen by many young research workers as faintly fuddy-duddy and is used less and less in advanced research this has the unfortunate consequence, adumbrated above, that the beneficial habit of using a wide range of magnifications in examining a material is less and less followed. [Pg.217]

Microscopy. A broad definition of microscopy is the observation and measurement of optical parameters with any instrument that uses energy sources such as photons, electrons or X-rays to... [Pg.143]

In order to obtain higher magnification than is possible with light microscopy, by a ratio of 1000 to 1, instruments employing magnetically... [Pg.144]

Both heated stages [224] and ambient temperature gas environments [225,226] have been developed for use in electron microscopy and both are combined [227,228] in the controlled atmosphere instrument. Pressures of up to 30 kPa and temperatures up to 1500 K have been used in studies of a wide variety of solid—gas and catalytic reactions [ 229]. [Pg.26]


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See also in sourсe #XX -- [ Pg.694 , Pg.695 ]




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Microscopy Instrumentation

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