Superelastic NiTi (51.0 at.% Ni) specimens reinforced with 0, 10 and 20 vol.% TiC particles were deformed under uniaxial compression while neutron diffraction spectra were collected. The experiments yielded in-situ measurements of the thermoelastic stress-induced transformation. The evolution of austenite/martensite phase fractions and of elastic strains in the reinforcing TiC particles and the...

The discovery of ligands that bind specifically to a targeted protein benefits from the development of generic assays for high-throughput screening of a library of chemicals. Protein powder diffraction (PPD) has been proposed as a potential method for use as a structure-based assay for high-throughput screening applications. Building on this effort, powder samples of bound/unbound states of sol...

PbMg1/3Nb2/3O3 (PMN) powder was prepared by citrate organic solution, and barium titanate (BT) seed particles were added to encourage the perovskite phase formation. Sintering was followed using the constant heating rate mode of a dilatometer, and it was observed that the seed concentration affected the PMN shrinkage rate and crystal structure. The study of the lattice parameters of the samples...

Dealumination of NH(4)-Y zeolite during steaming to 873 K was investigated with in situ, time-dependent, synchrotron radiation XRPD and in situ Al K-edge XAS. Water desorption is complete at 450 K, and ammonium decomposition occurs between 500 and 550 K. Only a small fraction of Al(3+) species (5%) leaves the framework during heating from 710 to 873 K; these species occupy site I' inside the so...

The crystal structure of Pigment Red 254 [P.R. 254, C18H10Cl2N2O2; systematic name: 3,6-bis-(4-chloro-phen-yl)-2,5-di-hydro-pyrrolo-[3,4-c]pyrrole-1,4-dione] was solved from laboratory X-ray powder diffraction data using the simulated annealing method followed by Rietveld refinement because the very low solubility of the pigment in all solvents impedes the growth of single crystals suitable for...

The photoluminescence of Ca(2)SiS(4):Eu powders was investigated in detail as a function of europium concentration (from 0.1% Ca substitution to the fully substituted Eu(2)SiS(4)). At low europium dopant concentration (<10%) the powders crystallize in an orthorhombic structure and the emission spectrum is dominated by two broad emission bands, at 564 and 660 nm. The emission can be tuned from y...

The crystal structure of an oscillatory zoned erythrite sample from Aghbar mine, Bou Azzer, Morocco, was refined using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data, Rietveld refinement, space group C2/m, and Z = 2. The crystal contains two sets of oscillatory zones that appear to have developed during epitaxial growth. The unit-cell parameters obtained are a = 10.24799(3) ...

Reference x-ray powder patterns and the crystal structures of the lanthanide com-determined by the x-ray Rietveld refinement technique. A structural trend was confirmed for this series of compounds. The compounds with smaller ionic radii are isostructural to the orthorhombic " green phase " (BaY2CuO5). The lattice parameters for compounds with R = Tm to Sm range from R is seven-fold coordinated...

Introduction: Imaging spectroscopy is one of the most powerful methods to characterize the surface of Mars, either from orbit or in situ using rovers. These observations have shown that iron chemistry and mineralogy dominates most of the surface processes. We have described in [1] a laboratory experiment in which elemental iron particles have been exposed to weathering in a simulated (CO 2 + H ...

Equal channel angular rolling (ECAR) is a severe  plastic deformation (SPD) technique which has been used to produce metal sheets with ultra-fine grain structure. In the present work, the relationships between the mechanical properties and microstructure of samples during the ECAR process have been investigated. The Rietveld method was applied to analyze the X-ray diffraction pattern and to det...