Gilles Berhault, A. Mehta, F. Manciu, R.R. Chianelli, P. Afanasiev 1 Institut de Recherches en Catalyse et Environnement de Lyon, IRCELYON, UMR 5256 CNRS – Université Lyon I, Villeurbanne, F-69626 (France) 2 Stanford Synchrotron Radiation Laboratory, Stanford University, Menlo Park, CA 94025 3 Materials Research Technology Institute, University of Texas at El Paso, El Paso, TX 79968 *Gilles.Ber...

ReO2 presents two crystalline variants, with monoclinic and orthorhombic structures. The former is metastable and irreversibly transforms to an orthorhombic structure above 460oC. The structure of the latter was determined from studies on monocrystalline samples, whereas for the monoclinic variant there are no single crystals available so far. It was found only one monoclinic variant and the st...

Why MgSO4·11H2O? Hydrous Mg-sulfate with 11 structural waters (11w hydrate), a new low temperature hydrated Mg-sulfate phase, was first reported in 2006 by Peterson & Wang [1]. They did a structural refinement using single-crystal XRD and suggested that the crystal molds in outcrops at Meridiani [2] could indicate melting and loss of the 11w hydrate. Chou et al. [3] proposed a phase boundary be...

This paper reports on some Round Robins conducted over the past twenty-five years. Although this review is not exhaustive, it outlines the objectives and the most frequent conclusions derived from the analysis of results. As the general follow up from these conclusions a proposal is here launched to establish an international network for the "Calibration Monitoring of the Diffractometers". INTR...

A new approach to sample handling for powder X-ray diffraction analysis is presented that allows characterization of poorly prepared samples. The technique relies on vibrations generated in a sample holder to create movement of the powdered sample in the absence of macroscopic movement of the sample holder itself. The major benefits over conventional sample handling strategies are: 1) the abili...

Institute of Exact Science, Federal University of Alfenas – UNIFAL, CEP 37130-000, Alfenas, MG, Brazil Department of Physics, Chemistry and Mathematics, Federal University of São Carlos – UFSCar, CEP 18052-780, Sorocaba, SP, Brazil Alan G. MacDiarmid Institute for Innovation and Business, National Nanotechnology Laboratory for Agribusiness – LNNA, Embrapa Agricultural Instrumentation, São Carlo...

The structure and thermostability of hyperfine amorphous Ni2B catalysts (HA-Ni2B) have been sttidied by EXAFS, XPD and DSC. The samples prepared by chemical reduction have been proved to be amorphous. The grain size is between 5 nm and 20 nm. A short-range order cluster is formed. The distances of Ni-B or Ni-Ni did not alter due to the change of the conditions but the coordination number of Ni ...

X-ray powder diffraction is one of the most potential characterization tools and a nondestructive technique for characterizing both organic and inorganic crystalline materials. The method previously used for measuring phase identification, quantitative analysis and to determine structure imperfections of samples from various disciplines such as geology, polymeric, environmental, pharmaceutical,...