Polarized measurements of oriented single crystals can be used to simplify the interpretation of X-ray absorption near edge structure (XANES) spectra by permitting a direct determination of the symmetry properties of a particular transition. We have utilized this technique to study the XANES spectra for several first-row transition metal complexes. Applications to the weak, ls+3d transition, to...

We present photoionization models accounting for both photoelectric and resonant absorption. Resonance absorption lines from C, O, Ne, Mg, Si S and Fe between 0.1 and 10 keV are treated. In particular we consider the complex of almost 60 strong Fe L absorption lines around 1 keV. We calculate profiles, intensities and equivalent widths of each line, considering both Doppler and natural broadeni...

We investigated the geometry of the iron ligand sphere of the native rabbit 15-lipoxygenase (15-LOX) by X-ray absorption spectroscopy using synchrotron radiation. The soybean LOX-1 was used as a reference compound because its iron ligand sphere is well characterized. For structural information the X-ray absorption spectra were evaluated using the Excurve Program (CCLRC Daresbury Laboratory, War...

A zeolite NaA (A-type zeolite of ca. 0.4 nm pore size; Linde Type A, LTA) membrane for the dehydration of alcohol was characterized by X-ray diffraction analysis (XRD). Also, the relationship between the X-ray absorption and the EtOH/H2O pervaporation (PV) dehydration performance (water selectivity and permeation flux) of the LTA membrane was first investigated. The LTA membranes used here were...

Currently the basis for standard X-ray computed tomography (CT) is absorption. A volumetric map of a specimen in three dimensions is generated from a set of absorption radiographs. The contrast of details strongly depends on a difference in absorption coefficient between the detail and the environment. However, when the absorption difference is low, sufficient contrast for a good quality X-ray ...

X-ray Absorption Spectroscopy (XAS) is a well-established analytical technique used extensively for the characterization of semiconductors in solid or liquid, crystalline or amorphous, bulk or nanoscale form. With this chapter, we provide a brief introduction to XAS, covering both theory and experiment, while we refer to more comprehensive texts for greater detail about this continually evolvin...

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X-ray PhotoElectron Emission Microscopy (X-PEEM) has found numerous applications in the surface microchemical analysis of materials science and biological specimens. We have reconfigured the MEPHISTO X-PEEM instrument, installed at the UW-Synchrotron Radiation Center, to measure true x-ray transmission spectra by converting transmitted photons to photoelectrons via a thin photocathode layer of ...

A rapid progress in the theoretical developments based on modulations of absorption cross section due to single and multiple scattering of an electron emitted from an inner shell by X-rays impinging on the target atom to understand the EXAFS and XANES in recent years and harnessing of the highly powerful synchrotron radiation source for the X-rays have bestowed immense capability on X-ray absor...

Presently seven nearby radio-quiet isolated neutron stars discovered in ROSAT data and characterized by thermal X-ray spectra are known. They exhibit very similar properties and despite intensive searches their number remained constant since 2001 which led to their name “The Magnificent Seven”. Five of the stars exhibit pulsations in their X-ray flux with periods in the range of 3.4 s to 11.4 s...