Analytical methods scanning electron microscope

Current methods used to image MCM-41 include (1) analytical transmission electron microscopy (TEM) to determine structure, size, morphology, and local chemical composition (2) energy-dispersive X-ray spectroscopy (EDXS) in a scanning electron microscope (SEM) to determine chemical composition 5 and (3) electron energy loss spectroscopy (EELS) for elemental analysis.6... 

Energy-dispersive analysis of X-rays was the chosen analytical method because of its sensitivity to elements heavier than sodium, its capability of mapping elemental distribution, and its capacity for combination with a scanning electron microscope. EDS microanalysis has been reported to be suitable for the determination of mordant treatments on historical fibers (8-10) and has been used to characterize metal wrappings of combination yarns (11-13). EDS microanalysis has also been used to determine the composition of pseudomorphs and fibers in the process of mineral replacement (13, 14, 15). 

For a thorough assessment of different types of fibers, special analytical methods have to be used. The scanning electron microscope (SEM) is usually the equipment of choice for the characterization of asbestos fibers. Energy disperse X-ray analysis (EDX) enables asbestos fibers to detected even at very low concentrations. This procedure requires very expensive technology and can be performed only by highly skilled technicians. 

Surface Characterization. Several analytical methods were used in characterizing the modified polymer surfaces. Energy Dispersive X-ray (EDX) spectra and electron micrographs of the surfaces were obtained using a JEOL JSM-IC848 scanning electron microscope in order to confirm the presence of phosphorus and chlorine. 

To get mechanistic information, gravimetric measurements should always go together with metallographic and analytical investigations aimed at the smdy of the morphology and the composition of the corrosion products and the metal in the vicinity of the surface. For this, a scanning electron microscope equipped with an X-ray microanalysis system is particularly well suited. Transmission electron microscopy in conjunction with electron diffraction, and conventional X-ray diffraction methods are also frequently applied. Surface analysis methods such as XPS, AES and SIMS permit the study of the oxide-metal interface and of initial oxide growth. 

The large size of CPOs allows their direct observation. For this purpose, scanning tunneling microscopy (STM) is the best method [32,34]. Electron microscopic analysis is used for phthalocyanine 3 and its derivatives however, most of the porphyrin derivatives are decomposed by electron beam irradiation. Presently, although only a limited number of researchers are able to perform atomic-scale resolution measurement, this powerful analytical method is expected to be used widely in the future. The author reported a summary of STM studies on porphyrins elsewhere [34]. 

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