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About: Analyser is a(n) research topic. Over the lifetime, 2122 publication(s) have been published within this topic receiving 18613 citation(s).
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Journal ArticleDOI
Abstract: A general framework is presented for the quantitative analysis of surfaces by X-ray photoelectron spectroscopy (XPS or ESCA). The approach starts by considering analysis using reference data recorded on the same instrument and under identical conditions as the analysed sample. Matrix factors are evaluated and the quantification for adsorbed layers and sputter profiles discussed. More popularly reference data are not recorded each time but are taken from the published literature. In this case the angular anisotropy term and analyser transmission functions need to be known. These are discussed and the analyser transfer functions of commercial spectrometers are presented in detail. Nine published reference data sets are assessed to test their correlation with the theoretical predictions. Theree sets are found to give moderate agreement but agree more closely with each other in their divergence from the theory for particular elements. This divergence enables a peak intensity factor to be defined which quantifies the intensity lost from a peak due to shake-up events, etc. With this factor and the analyser transfer functions quantification can be made to an accuracy of 10% in all instruments from a single reference data set.

340 citations

Journal ArticleDOI
TL;DR: Diffraction enhanced imaging is a new, synchrotron-based, x-ray radiography method that uses monochromatic, fan-shaped beams, with an analyser crystal positioned between the subject and the detector, and has the potential for use in clinical radiography and in industry.
Abstract: Diffraction enhanced imaging (DEI) is a new, synchrotron-based, x-ray radiography method that uses monochromatic, fan-shaped beams, with an analyser crystal positioned between the subject and the detector. The analyser allows the detection of only those x-rays transmitted by the subject that fall into the acceptance angle (central part of the rocking curve) of the monochromator/analyser system. As shown by Chapman et al, in addition to the x-ray attenuation, the method provides information on the out-of-plane angular deviation of x-rays. New images result in which the image contrast depends on the x-ray index of refraction and on the yield of small-angle scattering, respectively. We implemented DEI in the tomography mode at the National Synchrotron Light Source using 22 keV x-rays, and imaged a cylindrical acrylic phantom that included oil-filled, slanted channels. The resulting 'refraction CT image' shows the pure image of the out-of-plane gradient of the x-ray index of refraction. No image artefacts were present, indicating that the CT projection data were a consistent set. The 'refraction CT image' signal is linear with the gradient of the refractive index, and its value is equal to that expected. The method, at the energy used or higher, has the potential for use in clinical radiography and in industry.

257 citations

Book ChapterDOI
Abstract: The Cluster Ion Spectrometry (CIS) experiment is a comprehensive ionic plasma spec-trometry package on-board the four Cluster spacecraft capable of obtaining full three-dimensional ion distributions with good time resolution (one spacecraft spin) with mass per charge composition determination. The requirements to cover the scientific objectives cannot be met with a single instrument. The CIS package therefore consists of two different instruments, a Hot Ion Analyser (HIA) and a time-of-flight ion Composition and Distribution Function analyser (CODIF), plus a sophisticated dual-processor-based instrument-control and Data-Processing System (DPS), which permits extensive on-board data-processing. Both analysers use symmetric optics resulting in continuous, uniform, and well-characterised phase space coverage. CODIF measures the distributions of the major ions (H+, He+, He++, and O+) with energies from -0 to 40 keV/e with medium (22.5°) angular resolution and two different sensitivities. HIA does not offer mass resolution but, also having two different sensitivities, increases the dynamic range, and has an angular resolution capability (5.6° × 5.6°) adequate for ion-beam and solar-wind measurements.

241 citations

Journal ArticleDOI
Abstract: This paper presents the methods and techniques used in the recently developed JKMRC/FEI Mineral Liberation Analyser (MLA). The MLA system consists of a specially developed software package and a standard modern SEM fitted with an energy dispersive spectrum (EDS) analyser. The on-line program of the MLA software package controls the SEM, captures sample images, performs necessary image analysis and acquires EDS x-ray spectra unattended. Typically, 40 to 100 images (containing 4000 to 10,000 particles) are acquired for each sample block and a dozen blocks (of 30 mm in diameter) are measured overnight. The MLA off-line processing program transforms raw particle image with x-ray data into particle mineral maps and calculates bulk and liberation data from particle mineral maps.

238 citations

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Topic's top 5 most impactful authors

Martin P. Seah

5 papers, 410 citations

Mohamed M. El-Gomati

4 papers, 9 citations

Ian Keith Ludlow

3 papers, 33 citations

C.J. Carlile

3 papers, 34 citations

Konstantin Mikhailovitch Pavlov

3 papers, 48 citations