Wavelength dispersive analysis

The chemical composition of the TS-NU-1 samples were determined by X-ray fluorescence, the samples were analyzed for SiOz, TiOz and AI2O3 by a lithium tetraborate fusion followed by XRF wavelength dispersive analysis (3070, Rigaku). 

A section of root was studied using wavelength dispersive analysis. The distribution of Pt, as studied using both the Ma and La lines show that the platinum is concentrated in the cortical layers of the root, with very little passing into the vascular system. 

I99OB0I] Sintering, optieal microscopy, SEM, wavelength dispersive analysis, EDX, X-ray diffraction, TEM, DTA > 1180°C, high-speed steels (HSS) with Cu-P or Fe-P alloys powders addition... 

Samples were analyzed using a Cameca MBX electron microprobe equipped with a Tracor Northern computer control system, and quantitative wavelength dispersive analysis was performed using a modified version of Sandia TASK8. 

An SEM is usually equipped with an X-ray detector (allowing energy dispersive analysis of X-rays, EDX or wavelength dispersive analysis, WDX). Thus, the characteristic signal X-ray emission of a particular element can be displayed on the imaging screen, and the distribution of different elements on a surface can be readily obtained. Figure 1.26 reveals the origin of particles on a polymer surface with the help of EDX. 

Both the wavelength dispersive and energy dispersive spectrometers are well suited for quaUtative analysis of materials. Each element gives on the average only six emission lines. Because the characteristic x-ray spectra are so simple, the process of allocating atomic numbers to the emission lines is relatively simple and the chance of making a gross error is small. 

The incoming electron beam interacts with the sample to produce a number of signals that are subsequently detectable and useful for analysis. They are X-ray emission, which can be detected either by Energy Dispersive Spectroscopy, EDS, or by Wavelength Dispersive Spectroscopy, WDS visible or UV emission, which is known as Cathodoluminescence, CL and Auger Electron Emission, which is the basis of Auger Electron Spectroscopy discussed in Chapter 5. Finally, the incoming... 

The electron-optical performance of the EPMA system is indistinguishable from that of a conventional scanning electron microscope (SEM) thus, EPMA combines all of the imaging capabilities of a SEM with quantitative elemental analysis using both energy- and wavelength-dispersive X-ray spectrometry. ... 

X-Ray Fluorescence analysis (XRF) is a well-established instrumental technique for quantitative analysis of the composition of solids. It is basically a bulk evaluation method, its analytical depth being determined by the penetration depth of the impinging X-ray radiation and the escape depth of the characteristic fluorescence quanta. Sensitivities in the ppma range are obtained, and the analysis of the emitted radiation is mosdy performed using crystal spectrometers, i.e., by wavelength-dispersive spectroscopy. XRF is applied to a wide range of materials, among them metals, alloys, minerals, and ceramics. 

Examples of using reference samples for calibration can be found in several chapters of the uses Methods for Geochemical Analysis (Baedecker 1987). Solid reference sample powders are used in cahbrating the dc arc emission, energy-dispersive X-ray and instrumental neutron activation analyses described, while acid-dissolved rock reference samples are used for IGP emission analyses and fused reference samples are used for wavelength-dispersive X-ray analyses. 

Taggart JE Jr, Lindsay JR, Scott BA, Vivit DV, Bartel AJ, Stewart K C (1993) Analysis of geological materials by wavelength-dispersive X-ray fluorescence spectrometry. In Badecker PA, ed. U.S. Geological Survey Bulletin 1770. Methods for Geochemical Analysis, pp E1-E19. 

Falcone, R., A. Renier, and M. Verita, M. (2002), Wavelength-dispersive X-ray fluorescence analysis of ancient glasses, Archaeometry 44(4), 531-542. 

Elemental analysis can also be performed on SEM samples using x-ray spectrometer attachments [55], The techniques are known as energy dispersive x-ray (EDX) analysis and wavelength dispersive x-ray (WDX) analysis and require installation of a detector in the sample chamber. 

Potts, P.J., Webb, P.C. and Watson, J.S. (1985). Energy-dispersive X-ray fluorescence analysis of silicate rocks comparisons with wavelength-dispersive performance. Analyst 110 507-513. 

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