186,492 research outputs found
Evidence for [1s2p]3p shake-up channels in compounds and oxides of third-period elements
No full textX-ray photoemission spectra (XPS) of NaF, MgO, Al2O3, SiO2, InP, and NaH2PO4 collected using synchrotron radiation in the 1900-3400-eV energy range are reported. Accurate XPS spectra have been collected around the Na, Mg, Al, Si, and P 1s photoemission peaks including a region extending for a few hundred eV on the high-binding-energy side. Clear features associated with additional excitations of 2p electrons, more evident in low-Z elements, have been identified. The fine structure of these satellites, dominated by the lower-upper splitting, has been studied in different compounds as a function of the photon energy. Energy positions and splitting are consistent with theoretical predictions
Evidence for [1s2p]3p shake-up channels in compounds and oxides of third period elements
No full textTXM-Wizard: a program for advanced data collection and evaluation in full-field transmission X-ray microscopy
No full textAuthor-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Transmission X-ray microscopy for full-field nano imaging of biomaterials
No full textImaging of cellular structure and extended tissue in biological materials requires nanometer resolution and good sample penetration, which can be provided by current full-field transmission X-ray microscopic techniques in the soft and hard X-ray regions. The various capabilities of full-field transmission X-ray microscopy (TXM) include 3D tomography, Zernike phase contrast, quantification of absorption, and chemical identification via X-ray fluorescence and X-ray absorption near edge structure imaging. These techniques are discussed and compared in light of results from the imaging of biological materials including microorganisms, bone and mineralized tissue, and plants, with a focus on hard X-ray TXM at 64 40-nm resolution. \ua9 2010 Wiley-Liss, Inc.Peer reviewed: YesNRC publication: Ye
Synchrotron radiation-induced total reflection X-ray fluorescence analysis
No full textSynchrotron radiation-induced total reflection X-ray fluorescence (SR-TXRF)
analysis is a high sensitive analytical technique that offers limits of detection
in the femtogram range for most elements. Besides the analytical aspect,
SR-TXRF is mainly used in combination with angle-dependent measurements
and/or X-ray absorption near-edge structure (XANES) spectroscopy to gain
additional information about the investigated sample. In this article, we
briefly discuss the fundamentals of SR-TXRF and follow with several examples
of recent research applying the above-mentioned combination of techniques
to analytical problems arising from industrial applications and
environmental research
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Orientational Disorder In Amorphous-silicon Probed By Xanes (x-ray Absorption Near Edge Structure)
No full textThe difference between the K-edges XANES (X-ray Absorption Near Edge Structure) spectra of crystal and amorphous silicon is discussed. We show that the multiple scattering signal gives a large contribution to the total absorption in crystalline silicon in an energy range of about 70eV. The double scattering term probing the triplet distribution function gives the major contribution to the XANES. We show that the difference between the crystalline and amorphous absorption spectra is due mainly to the crystalline multiple scattering signal which is quenched in the amorphous spectrum. The suppression of the signal due to the triplet distribution function in the amorphous silicon is assigned to the large orientational disorder
Three-dimensional imaging of chemical phase transformations at the nanoscale with full-field transmission X-ray microscopy
No full text- …
