ELECTRON DISPERSIVE X-RAY ANALYSIS

The shock-modified composite nickel-aluminide particles showed behavior in the DTA experiment qualitatively different from that of the mixed-powder system. The composite particles showed essentially the same behavior as the starting mixture. As shown in Fig. 8.5 no preinitiation event was observed, and temperatures for endothermic and exothermic events corresponded with the unshocked powder. The observations of a preinitiation event in the shock-modified mixed powders, the lack of such an event in the composite powders, and EDX (electron dispersive x-ray analysis) observations of substantial mixing of shock-modified powders as shown in Fig. 8.6 clearly show the first-order influence of mixing in shock-induced solid state chemistry. 

Wan] SEM-Electron Dispersive X-ray analysis Partial isothermal sections at 800°C, (Cu)/a phase boundaries at 900°C, (Cu)/y phase boundaries at 1000°C, (Cu)/y phase boundaries at 1200°C, (L)/y phase boundaries... 

Kiml, 2000Kim2] Pyrometry, optical microscopy, SEM -electron dispersive X-ray analysis 40 to 80 mass% Cu, 10 to 50 mass% Co, 10 to 50 mass% Fe, liquidus and solidus temperatures, melt separation temperatures... 

Wan] SEM - electron dispersive X-ray analysis of quenched samples 800 to 1000°C, a/(Cu) and y/iCu) phase boxmdaries... 

A scanning electron microscope can also be equipped with additional instmmentation for electron-excited x-ray analysis (9). In many systems, this is performed in the mode known as energy dispersive x-ray analysis (edx). Other common acronyms for this method are eds for energy dispersive spectroscopy or edax for energy dispersive analysis of x-rays. 

Scanning electron microscopy (thickness topography porosity barrier layers fracture sections) Energy dispersive X-ray analysis (EDX)... 

As illustrated by Eig. 4.13, an electron microscope offers additional possibilities for analyzing the sample. Diffraction patterns (spots from a single-crystal particle and rings from a collection of randomly oriented particles) enable one to identify crystallographic phases as in XRD. Emitted X-rays are characteristic for an element and allow for a determination of the chemical composition of a selected part of the sample. This technique is referred to as energy-dispersive X-ray analysis (EDX). 

Laser Ablation ICP Optical Emission Spectrometry ICP Mass Spectrometry Transmission Electron Microscopy with Energy-Dispersive X-Ray Analysis... 

The boron nitride obtained in this study was characterized by infrared spectroscopy, powder x-ray diffractometry and transmission electron microscopy. Trace elemental analyses were also performed by energy dispersive x-ray analysis and carbon arc emission spectroscopy. Representative spectra are displayed in Figures 2-4. 

In an article published in Analytical Chemistry in 2004, Keune and Boon [2004a] present the application of ToF-SIMS analysis to a paint cross-section. The sample used was from the panel painting The Descent from the Cross (Museo del Prado, Madrid) by the early Flemish painter Rogier van der Weyden (1399/1400 1464). Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX) and infrared microscopy were also used to complete and confirm the results. 

Transmission electron microscopy energy dispersive X-ray analysis has also been used to image intracellular Se granules present from Se bioreduction in bacteria. Reduction of selenite and the deposition of elemental Se in cell cytoplasm or in the extracellular space may be lead to promising bioremediation schemes.172... 

Buchan [92] has carried out a study using electron microscopy combined with energy dispersive X-ray analysis, to determine the location and nature of the stored phosphorus in activated sludge samples from seven different treatment plants in South Africa, which all show enhanced phosphorus removal. The results indicate that there is a biological mechanism of enhanced phosphorus uptake in activated sludge. 

K. F.J. (1968) Solid-state energy-dispersion spectrometer for electron-microprobe X-ray analysis. 

Figure 2. Schematic of a scanning electron microscope equipped for energy dispersive X-ray analysis...

Semiconducting thin films of CdSe were electrochemically deposited on Ti substrates [186,187]. The film electrodes were characterized with photoelectrochemical imaging, optical microscopy, and scanning electron microscopy (SEM)/energy-dispersive X-ray analysis. 

Energy-dispersive X-ray analysis (EDAX) using a scanning electron microscope confirmed the presence of sulfur and phosphorus in solid samples of the [l,2,3]triazolo[4,5-rf [l,3,2]thiazaphospholes 57 in the expected atomic ratio of 2 1 <1997CC2149>. 

The most frequently applied analytical methods used for characterizing bulk and layered systems (wafers and layers for microelectronics see the example in the schematic on the right-hand side) are summarized in Figure 9.4. Besides mass spectrometric techniques there are a multitude of alternative powerful analytical techniques for characterizing such multi-layered systems. The analytical methods used for determining trace and ultratrace elements in, for example, high purity materials for microelectronic applications include AAS (atomic absorption spectrometry), XRF (X-ray fluorescence analysis), ICP-OES (optical emission spectroscopy with inductively coupled plasma), NAA (neutron activation analysis) and others. For the characterization of layered systems or for the determination of surface contamination, XPS (X-ray photon electron spectroscopy), SEM-EDX (secondary electron microscopy combined with energy disperse X-ray analysis) and... 

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