Scanning electron microscope components

The considerable stabilizing effect observed at low % PS, possibly is related to the compatibility of the components in the blends. From scanning electron microscopic studies, it is clear that all compositions, a two phase... 

Figure 4- Scanning electron microscope micrographs of zeolitic components...

Metal location is but one of a number of applications for scanning electron microscope studies in catalysis. Other applications are the study of the morphology of platinum-rhodium gauzes used in the oxidation of ammonia and the poisoning of catalysts, in which the scanning electron microscope results show the location of poisons such as compounds containing sulfur, phosphorus, heavy metals, or coke relative to the location of the catalytic components. 

Figure 16.4 Basic components of a scanning electron microscopic suitable for FDR detection.

There are also catalyst formulations which have highly dispersed metals which are deliberately heterogeneously distributed on a support. If the microscopist is aware of the situation, he can take precautions in the sample preparation. This type of sample is the worst possible case to analyze because not only does the analyst have a complex mixture of components to sort out, but the analysis statistics are very poor. Consequently, additional time is usually required to survey the catalyst particles in order to establish a consensus of how it was constructed. Specialized specimen preparation such as ultramicrotoming and scraping the exterior of a sphere or extrudate may alleviate some of the interpretation problems. Additional aid may be solicited from a scanning electron microscope wherein an elemental distribution of a polished cross section of the catalyst sphere or extrudate can be made. 

Figure 7.9 is a diagrammatic cross-section of a scanning electron microscope. The components used to obtain a focused electron beam at the sample constitute the electron column. This must be maintained under a secondary vacuum. 

Scanning electron microscopes and energy dispersion X-ray analysis techniques have been used (169) to examine the distribution and location of the components of water-based preservatives applied to wood. Subsequently, the selective penetration of anions into the cell wall with the cations remaining in the cell lumen has been shown iron oxide pigments were completely deposited at the wood surface. 

Chemical analysis a sodium thiosulfate volumetric method for Cu, x-ray fluorescence for Zn, carbon and sulfur analysis (LECO CS-344) and a benzidine hydrochloride precipitation method for S04 X-ray diffraction for the measurement of Cu crystallite size and bulk component analysis scanning electron microscope (Phillip SEM-5Q5) XPS spectrometer (KRATOS XSAM 800). 

Fig. 4.2 An scanning electron microscope (SEM). Major components include the sample vacuum...

Compositional Characterization. The composition of the bulk samples was not determined since the components to these refractories were not considered sufficiently volatile to distort the nominal stoichiometry. Micro-analysis of the materials was performed in an effort to determine the homogeneity of the product crystals. These EDAX (Energy Dispersive X-ray Analysis) studies were performed by use of a Phillips model 505 scanning electron microscope. Microscopic investigation of the macrostructure of the ceramic were also performed using this instrument. 

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