SEM-EDX techniques

The decrease of 90% in the ash content could be explained by the removal of individual mineral phases in all particle sizes. Removal of organic sulfur was corroborated by a direct SEM-EDX technique. 

Two different thermal methods were used for the analysis of the high-temperature behavior of the various ash san5>Ies, i.e., simultaneous DTA/TGA using a NETSCH STA 429 friermal analysis instrument, and sintering tests performed in a simple muffle furnace, both in combination with a SEM/EDX technique for the elemental analysis of the thermally treated ash samples, using a JEOL 6300 scaiming microscope. 

The objective of the analysis of the thermally modified ash samples from the above two treatments by the SEM-EDX technique was to identify the main elements participating in the formation of the transformed ash structure and possibly obtain a better understanding of the phenomenon, by a correlation of the SEM-EDX results (presented in Tables 4-6) with the elemental analysis of the biomass ash (Table 2). 

Summary The question of the nature of the catalytically active copper species in Rochow contact masses has been investigated using the SEM/EDX technique. The results do not support the hypothesis of active ri-CusSi, but they provide more direct evidence for the existence and the catalytic action of X-ray amorphous Cu-Si surface species, i.e., extremely dispersed particles or even two-dimensional species like Cu Si surface compounds, which we proposed recently. The investigation of zinc-promoted and non-promoted contact masses on basis of the pure and technical-grade silicon showed that the mode of operation of the famous Rochow promoter zinc can be understood rather as a moderation than as a real acceleration. By moderating the initial reaction rate, the promoter enables a sufficiently high stationarity of the reaction. 

In the following, the present knowledge about these points, inclusive our own recent experiences, will shortly be outlined once more, and it will be shown what we could learn about active copper species and zinc promoter action by combining catalytic tests with the spatially resolving SEM/EDX technique. 

Non-promoted and zinc-promoted Rochow contact masses on the basis of pure and of technical-grade silicon were investigated by catalytic tests and by the spatially resolving SEM/EDX technique. 

Methods of analysis for GSR have evolved along with the instrumentation available for elemental analysis. Prior to the advent of scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) techniques, (flame and graphite furnace) atomic absorption was the principal analytical technique employed. Suspected GSR was collected with the use of wipes or swabs moistened with 1% nitric acid, and the residue collected was introduced into the instrument. Less frequently used were neutron activation analysis (NAA), anodic stripping voltammetry, and photoluminescence techniques. ICP methods (AES and MS) appear promising, but have not been widely used to date for GSR. 

Room-Temperature Ionic Liquid-Based SEM/EDX Techniques for Biological Specimens and in situ Electrode Reaction... 

In this present study, we basically showed dependence of the number of reduced cobalt metal surface atoms on dispersion of cobalt oxides along with the presence of rutile phase in titania. Both XRD and SEM/EDX results (not shown) revealed good distribution of cobalt oxides over the titania support. However, it can not differentiate all samples containing various ratios of rutile/anatase phase. Thus, in order to determine the dispersion of cobalt oxide species on titania, a more powerful technique such as TEM was applied with all samples. The TEM micrographs for all samples are shown in Figure 1. The dark spots represented cobalt oxides species present after calcination of samples dispersing on titania consisting various... 

M.T. Domenech Carbo, M.J. Casas Catalan, A. Domenech Carbo, R. Mateo Castro, J.V. Gimeno Adelantado, F. Bosch Reig, Analytical Study of Canvas Painting Collection from the Basilica de la Virgen de los Desamparados using SEM/EDX, FT IR, GC and Electrochemical Techniques, Fresenius Journal of Analytical Chemistry, 369,571 575 (2001). 

Electron paramagnetic resonance spectroscopy (EPR) (also called electron spin resonance spectroscopy, ESR) has been scarcely applied in the field of art and art conservation. Some work can be found in which EPR is used as complementary technique to SEM-EDX, NMR, and mass spectrometry (MS) for studying free radicals occurring in polymerization, pyrolytic, oxidative, and other radical degradative processes in artwork, as well as in the characterization of varnishes and oleoresinous media [42]. 

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... 

Depth profiles of matrix elements on Mn- and Co-perovskite layers of fuel cathodes have been measured by LA-ICP-MS in comparison to other well established surface analytical techniques (e.g., SEM-EDX).118 On perovskite layers at a spatial resolution of 100p.m a depth resolution of 100-200 nm was obtained by LA-ICP-MS. The advantages of LA-ICP-MS in comparison to other surface analytical techniques (such as XPS, AES, SIMS, SNMS, GD-OES, GDMS and SEM-EDX) are the speed, flexibility and relatively low detection limits with an easy calibration procedure. In addition, thick oxide layers can be analyzed directly and no charging effects are observed in the analysis of non-conducting thick layers. 

The interaction of cesium ions with feldspars at 150°C and 200°C has been studied in distilled water, granite groundwater and saline solution Pollucite, CsAlSi206, was identified by infrared spectroscopy, and was formed as a cubic crystalline phase. Surface analytical techniques (XPS, SAM, SIMS and SEM/ EDX) show Cs to be sorbed onto the mineral surfaces and alteration products. The mechanism of pollucite formation and its relevance to cesium transport/ retardation in the near field of a nuclear waste-disposal vault is discussed. 

Within this technique, we include EDX (energy dispersive x-ray analysis), WDX (wavelength dispersive x-ray analysis), and XRF (x-ray fluorescence analysis). In all of these, x-rays emitted from a sample are analyzed. In one case, they are created by bombarding the sample with x-rays (XRF), and in the others, they are created by high energy electron beam as in an SEM (EDX, WDX). 

A. Zeichner, H. A. Foner, M. Dvorachek, P. Bergman, and N. Levin, Concentration Techniques for the Detection of Gunshot Residues by Scanning Electron Microscopy/Energy Dispersive X-Ray Analysis (SEM/EDX), Journal of Forensic Sciences 34, no. 2 (March 1989) 312. 

The ability to detect organic constituents in FDR from ammunition with single-based propellant was the ultimate goal. If this proved impossible, the investigation would at least clarify the situation and improve the detection method for NG, which could serve as a useful complementary technique to SEM/EDX. If particles in the indicative category were accompanied by NG, it would substantially raise the significance level of such particles. 

The analytical methods currently used by this laboratory are chromatography (GC/TEA HPLC/PDME) for explosive residues and the particle analysis method (SEM/EDX) for FDR. The latter method involves the detection and identification of individual FDR particles therefore any sampling technique must be nondestructive. 

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