Computer-controlled scanning electron

Kennedy, S. K., Walker, W and Forslund, B. (2002). Speciation and characterisation of heavy-metal contaminated soils using computer-controlled scanning electron microscopy. Environ. Forensics 3,131-143. 

Kim D. and Hopke P. K. (1988) Classification of individual particles based on computer-controlled scanning electron-microscopy data. Aerosol Sci. Technol. 9, 133-151. 

Gupta R. P., Wall T. F., Kajigaya I., Miyamae S. Tsumita, Y. (1998) Computer-Controlled Scanning Electron Microscopy of Minerals in Coal -Implications for Ash Deposition. Prog. Energy Combust. 5c/., 24, 523-43. 

It is common practice to make a distinction between the inorganic constituents of so-called "Eastern" and "Western" coals By definition. Western coals are those for which the CaO+MgO content exceeds the Fe203 content of the ash, while the reverse is true for Eastern coals [ 1 I The inorganic constituents in Eastern coals, which are principally bituminous in rank, are predominantly in the form of discrete mineral particles. Clay minerals (kaolinite, illite) are usually dominant, followed by quartz and pyrite. The range and typical values of the mineral distribution and ash chemistry of Eastern coals are shown in Table I. These data were determined from computer-controlled scanning electron microscopy (CCSEM), Mossbauer spectroscopy, and other measurements on over a hundred coals. 

Seaton A, Cherrie J, Dennekamp M, Donaldson K, Hurley JF, Tran CL (2005) The London underground dust and hazards to health. Occup Environ Med 62 355-362 Sitzmann B, Kendal M, Williams I (1999) Characterisation of airborne particles in London by computer-controlled scanning electron microscopy. Sci Total Environ 241 63-73 Vekemans B, Janssens K, Vincze L, Adams F, Van Espen P (1994) Analysis of X-ray spectra by iterative least squares (AXIL) new developments. X-Ray Spectrom 23 278-285 Zimmer AT, Biswas P (2001) Characterization of the aerosols resulting from arc welding processes. J Aerosol Sci 32 993-1008... 

Watt, J., 1998. Automated characterisation of individual carbonaceous fly-ash particles by computer controlled scanning electron microscopy analytical methods and critical review of alternative methods. Wat. Air SoU Pollut. 105 309-327. 

Kindratenko, V.V., Vanespen, P.J.M., Treiger, B.A. and Vangrieken, R.E. (1994). Fractal dimensional classification of aerosol particles by computer-controlled scanning electron microscopy. Environ. Sci. TechnoL, 28, 2197—2202. 

Among the variety of micro-analytical techniques used, electron probe X-ray micro-analysis (EPXMA) and computer controlled scanning electron microscopy with energy-dispersive X-ray detection (CC-SEM/EDX) are most commonly used. Both can be used in fully automated mode, and in combination with cluster analysis and/or multivariate techniques. They are ideally suited for the analysis of representative numbers (300-1000... 

The Physical Electronics 680 Nanoprobe employs a field emission electron gun, and this results in a spatial resolution of less than lOnm. Ion bombardment for depth profiling is available in the SAM, and both the electron beam and the ion beam are computer controlled so that depth profiles can be run automatically, and maps and line scan of Auger electron distributions can be generated. 

The AFM has a number of elements common to STM the piezoelectrc scanner for actuating the raster scan and z positioning, the feedback electronics, vibration isolation system, coarse positioning mechanism, and the computer control system. The major difference is that the tunneling tip is replaced by a mechanical tip, and the detection of the minute tunneling current is replaced by the detection of the minute deflection of the cantilever. 

For the detailed study of reaction-transport interactions in the porous catalytic layer, the spatially 3D model computer-reconstructed washcoat section can be employed (Koci et al., 2006, 2007a). The structure of porous catalyst support is controlled in the course of washcoat preparation on two levels (i) the level of macropores, influenced by mixing of wet supporting material particles with different sizes followed by specific thermal treatment and (ii) the level of meso-/ micropores, determined by the internal nanostructure of the used materials (e.g. alumina, zeolites) and sizes of noble metal crystallites. Information about the porous structure (pore size distribution, typical sizes of particles, etc.) on the micro- and nanoscale levels can be obtained from scanning electron microscopy (SEM), transmission electron microscopy ( ), or other high-resolution imaging techniques in combination with mercury porosimetry and BET adsorption isotherm data. This information can be used in computer reconstruction of porous catalytic medium. In the reconstructed catalyst, transport (diffusion, permeation, heat conduction) and combined reaction-transport processes can be simulated on detailed level (Kosek et al., 2005). 

Since the last edition (1978), technological developments, such as improved electron microscopy (since Ernst Ruska, 1931), chemical analysis by microprobe (since Raymond Castaing, 1951), scanning electron microscopy (since Oatley McMullan, 1952), automatic computer-controlled instrumentation and software for structure determination, have made it possible to carry out the chemical, structural, morphological and physical characterization of tiny particles of new minerals (on the scale of micrograms) within a few days or weeks computerized structural and morphological drawings can be produced within minutes. 

Recently Kaiser and collaborators have developed new possibilities by means of a computer-controlled system 4i,44). They have coupled a desk computer (Apple II) via an AD-converter to the signal output of a Camag-scanner. Additionally, the computer is connected to the control electronics of the scanning table of the densitometer. Thus the transmission of the raw measuring data and the computer-control of the automatic scan is possible. 

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