Gallium nitride crystals with definite faces have been fabricated by d.c. arc discharge using gallium and Hz + NH, as starting materials. Transmission electron microscope, selected area diffraction and X-ray diffraction investigation of the as-grown GaN Srystals show thtt the well faceted crystals are single crystalline GaN having a wnrtzite structure with lattice constants a, = 3.18 A and cu =...

The use of X-ray diffraction to identify crystals from the fluid obtained from a brain tap is illustrated. The procedure for making this type of analysis is described and a very brief description of X-ray diffraction process given. Photographs of the powder diffraction patterns are included, as well as a table giving the interplanar distances and relative intensities corresponding to the patter...

the x-ray charge density analysis of a hydroxynaphthoquinnne derivative was obtained by multipolar hansen-coppens formalism refinement through high resolution x-ray diffraction data at 100(1) k. the molecularproperties of the title compound resulted from the combined experimental and the quantum theory of atoms inmolecules (qtaim) studies. the topological properties of the covalent bonds and of...

the knoevenagel condensation of aromatic aldehydes with barbituric acid, dimedone and malononitrile occurred in the presence of bf3/nano-γ-al2o3 at room temperature in ethanol. this catalyst is characterized by powder x-ray diffraction (xrd), fourier transform infrared spectroscopy (ft-ir), thermal gravimetric analysis (tga), field emission scanning electron microscopy (fesem) and energy-disper...

The Advanced Photon Source (APS) at Argonne National Laboratory was used to obtain real-time, high-resolution x-ray diffraction measurements to determine the microscopic response of shock-compressed single crystals. Disk shaped samples were subjected to plane shock wave compression by impacting them with half-inch diameter, flat-faced projectiles. The projectiles were accelerated to velocities ...

generally arranged at a distance of 0.1 nm to 0.5 nm from one another. When such a substance is irradiated with X-rays having a wavelength roughly equivalent to the interatomic or intermolecular distance, the Xray diffraction phenomenon will take place. X-ray diffraction is widely used in the semiconductor field because it is nondestructive and yields crystal structure information relatively ea...

ruthenium dioxide nanoparticles (ruo2 ) with an average particle size of 50 nm are readily synthesized from rucl3.xh2o via the precipitation process in the presence of in-situ sodium octanoate as anionic surfactant. the phase composition, morphology, lattice parameters and size of nanoparticles in these products are characterized by fourier transform infrared spectroscopy (ft-ir), x-ray diffrac...

cotio3-clay nano-composites were synthesized via a conventional sol-gel method; the gel was calcinated at 500 - 800°c for 2 hours. the presence of rhombohedra phase of cotio3 in clay matrix was confirmed by xrd, ftir, sem. cobalt titanate-clay nano-composites were prepared with 5-20%(w/w) by sol-gel method. the spectra results were investigated at 20% (w/w) concentration .the optimum condition ...

the synthesis of nanocrystalline fe3al powder by mechanical alloying as well as the structural ordering of the synthesized fe3al particles during the subsequent thermal analysis were investigated. mechanical alloying was performed up to 100 hours using a planetary ball mill apparatus with rotational speed of 300 rpm under argon atmosphere at ambient temperature. the synthesized powders were cha...

in the present work, we report a suitable approach for the preparation of batio3 nanostructures via the hydrothermal condition using dolapix et85 as surfactant. the powders were investigated by x-ray diffraction (xrd), scanning election microscopy (sem), energy-dispersive x-ray spectroscopy (edax), field emission transmission electron microscopy (fetem), selected area electron diffraction (saed...