Synchrotron radiation XRF

In their reviews in the Journal of Analytical Atomic Spectrometry series. Atomic Spectrometry Update and Atomic Mass Spectrometry and X-Ray Fluorescence Spectrometry, Bacon etal. (1991, 1993) include various variants of X-ray fluorescence spectrometric techniques such as synchrotron radiation XRF microprobe (SRXRF-microprobe), X-ray microfluorescence (XRMF), total reflection XRF (TXRF), and synchrotron radiation XRF (SRXRF). This tradition continues in reviews in this journal dedicated to X-ray fluorescence spectrometry (Potts et al. 2001,... 

The analysis was performed by XRF method with SR. SRXRF is an instrumental, multielemental, non-destructive analytical method using synchrotron radiation as primary excitation source. The fluorescence radiation was measured on the XRF beam-line of VEPP-3 (E=2 GeV, 1=100 mA), Institute of Nuclear Physics, Novosibirsk, Russia. For quality control were used international reference standards. 

Two different experiments have been performed at ID18F (p-XRD and p-XRF) and ID21 (p-XRF and p-XANES) beamlines at the ESRF (European Synchrotron Radiation Facilities, Grenoble, France). 

Direct analysis 7.1 XRD, XRF, infrared spectroscopy (NIR and MIR), solid-state nuclear magnetic resonance (NMR), advanced spectroscopy using synchrotron radiation, neutron activation, fluorescence, and visible and electron microscopy... 

Inner electrons are usually excited by X-rays. Atoms give characteristic X-ray absorption and emission spectra, due to a variety of ionization and possible inter-shell transitions. Two relevant refined X-ray absorption techniques, that use synchrotron radiation, are the so-called Absorption Edge Fine Structure (AEFS) and Extended X-ray Absorption Fine Structure (EXAFS). These techniques are very useful in the investigation of local structures in solids. On the other hand, X-Ray Fluorescence (XRF) is an important analytical technique. 

SR-XRF synchrotron radiation X-ray fluorescence spectrometry SS solid sampling... 

X-ray fluorescence analysis has a long history as a standard technique for analysis of mm to cm specimens using a hot-cathode X-ray source. However, the X-ray flux from a hot-cathode source is too divergent (isotropic emission) to permit efficient focusing. Thus, the niche of the synchrotron X-ray beam is in microbeam applications of the XRF technique, the inherent collimation and polarization of synchrotron radiation is well suited to use in an XRF microprobe. Details of synchrotron radiation generation are given in an accompanying chapter (Sham and Rivers, this volume). 

Hunter DB, Bertsch PM, Kemner KM, Clark SB (1997) Distribution and chemical spedation of metals and metalloids in biota collected from contaminated environments by spatially resolved XRF, XANES, and EXAFS. Journal de Physique IV France 7 767-771 Ice GE (1996) Microbeam forming methods for synchrotron radiation. X-ray Spectrum 26 315-326 Jackson BP, Shaw-Allen P, Hopkins WA, Bertsch PM (2002) Trace element speciation in largemouth bass (Micropterus salmoides) from a fly ash settling basin by liquid chromatography-ICP-MS. Analytical and Bioanalytical Chemistry, in press... 

Synchrotron radiation also has many applications in geological sciences, particularly for determination of the local environment, geometry, and coordination of a specific element. Synchrotron sources can be used in XRF analysis, providing high-resolution elemental maps. Synchrotron-based X-ray investigations are frequently used to investigate the sorption of elements onto mineral or particle surfaces. 

Abbreviations AES, Auger emission spectrometry CRM, Certified reference material DL, Detection limit ED, Energy dispersive ESRF, European Synchrotron Radiation Facility EXAES, Extended X-ray absorption fine structure NEXAFS, Near edge X-ray absorption fine structure PCI, Phase contrast imaging RM, Reference material SR, Synchrotron radiation SRM, Standard reference material TXRF, Total reflection X-ray fluorescence XANES, X-ray absorption near edge structure XAS, X-ray absorption spectrometry XDM, X-ray diffraction microscopy XFCT, X-ray fluorescence computerized microtomography XPEEM, X-ray photoelectron microscopy XPS, X-ray photoelectron spectrometry XRD, X-ray diffraction XRF, X-ray fluorescence... 

The second major variant of the XRF technique, which in the last decade has received a lot of attention, both with respect to the methodological developments and regarding its applications in diverse fields, is micro-XRF (p-XRF). This microanalytical variant of bulk XRF is based on the localized excitation and analysis of a microscopically (now even submicroscop-ically) small area on the surface of a larger sample, providing information on the lateral distribution of major, minor, and trace elements in the material under study. The p-XRF can be exploited with laboratory X-ray sources but found its most important areas of application when combined with a synchrotron radiation (SR) source (Janssens et al. 2000). 

Experimental (dots) and simulated (solid curve) synchrotron radiation-X-ray fluorescence (SR-XRF) spectra obtained for the NIST SRM 1577b bovine liver standard, corresponding to 21 keV excitation at the European Synchrotron Radiation Facility (ESRF) ID18F end-station (Adapted from Vincze et al. 2004)... 

Kanngiesser et al. (2003) demonstrated the principle of localized detection and sample depth-scanning for synchrotron radiation-induced XRE Vincze et al. (2004) gave the full characterization of polycapillary-based confocal XRF and its applications for 3D trace-element analysis. 

Figure 1.10 Schematic flowchart for the two alternate workflows for high-throughput X-ray absorption spectroscopy (HT-XAS). Synchrotron radiation analysis consists of mapping the metal distribution using X-ray fluorescence (XRF), using XANES for metal speciation and using EXAFS for metal-site structural analysis of the metalloproteome. 2005 International Union of Crystallography.

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