The x-ray standing wave method ~XSW! and high-resolution x-ray diffraction were used to study the structural perfection and polarity of GaN epitaxial thin film grown by hydride vapor phase epitaxy on the Si-face SiC substrate. The x-ray standing wave was generated inside the 300 nm thin film under the condition of Bragg diffraction from the film. Excellent crystalline quality of the GaN film wa...

A crucial issue in coherent x-ray diffraction imaging experiments is how to increase the signal-to-noise ratio when measuring relatively weak diffraction intensities from a nonperiodic object. A novel crystal guard aperture is described that makes use of a pair of multiple-bounce crystal optics to eliminate unwanted parasitic scattering background. This background is often produced by upstream ...

Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-...

in this research different types of al2o3 were used as supports to prepare catalysts for dehydrogenation of isobutane to isobutene. these supports were al2o3 from merck, axen and gamma al2o3 synthesized from al(oh)3. sn/pt/al2o3 catalysts were prepared by sequential impregnation, at first pt and then sn was deposited. characterization of catalysts was performed by x-ray powder diffraction (xrd)...

in the current paper,nanostructured nickel oxide (nio) were synthesized by co-precipitation method using nickel(ii) chloride hexahydrate (nicl2.6h2o) and sodium hydroxide (naoh) as starting material. structural, optical and magnetic properties of nanostructures were characterized by x-ray diffraction (xrd), scanning electron microscopy (sem), atomic force microscope (afm), uv–vis absorption; fo...

the nanocrystallization of co67fe4cr7si8b14 amorphous ribbons which prepared by planar flow melt spinning process (pfms) was investigated. crystallization of the ribbons was studied by differential thermal analysis (dta), x-ray diffraction (xrd) and transmission electron microscopy (tem). the dta result of amorphous ribbon at heating rate of 10˚c/min showedoccurrence of phase transitions in two...

our aim in this work is the synthesis and study optical and structural properties of gold nanoparticles.gold (iii) chloride trihydratewas taken as metal precursor, ascorbic acid at the presence of an appropriate amount of naoh as reducing agent and polyvinylpyrrolidonek-30 (pvp k-30) as a stabilizing and capping agent. the reaction was performed in high-speed stirring rate at room temperature.s...

Rare-earth co-doping in inorganic materials has a long-held tradition of facilitating highly desirable optoelectronic properties for their application to the laser industry. This study concentrates specifically on rare-earth phosphate glasses, (R2O3)x(R'2O3)y(P2O5)(1-(x+y)), where (R, R') denotes (Ce, Er) or (La, Nd) co-doping and the total rare-earth composition corresponds to a range between ...

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...