نتایج جستجو برای: ray diffraction

تعداد نتایج: 327749  

1998
S. A. Stepanov E. A. Kondrashkina

A generalized dynamical theory has been developed that extends previous models of x-ray diffraction from crystals and multilayers with vertical strains to the cases of grazing incidence and/or exit below the critical angle for total specular reflection. This provides a common description for extremely asymmetric diffraction, surface ~‘‘grazing-incidence’’!, and grazing Bragg-Laue diffraction, t...

Journal: :international journal of nano dimension 0
s. khorrami department of chemistry, north tehran branch, islamic azad university, tehran, iran. f. gharib department of chemistry,shahid beheshti university,tehran, iran. g. mahmoudzadeh department of chemistry, north tehran branch, islamic azad university, tehran, iran. s. sadat sepehr department of chemistry, north tehran branch, islamic azad university, tehran, iran. s. sadat madani department of chemistry, north tehran branch, islamic azad university, tehran, iran. n. naderfar department of chemistry, north tehran branch, islamic azad university, tehran, iran. s. manie

sol–gel auto-combustion is a unique combination of the combustion and the chemical gelation processes. in this work, nanosize (d) powders with compositions of znfe2o4 were synthesized by sol–gel combustion method. the puffy, porous brown powders as-combusted was calcined at the temperature of 750–1000◦c for 4 h. these powders are characterized by x-ray diffraction and scanning electron microsco...

Journal: :شیمی کاربردی 0
سید رضا عظیمی پیرسرائی حسن اصیلیان مهابادی احمد جنیدی جعفری زهره فرهمند کیا جعفر تاران

the characterizations of natural diatomite from birjand deposit (iran) were studied such as chemical compositions, specific surface area, total pore volume, pore size distribution and xrd. the diatomite that was treated only with sulfuric acid displayed a larger surface area, expanded total pore volume and increased pore size in comparison with both washed natural diatomite with deionized water...

Journal: :international journal of environmental research 2015
s. gitipour m.a. hosseinpour n. heidarzadeh p. yousefi a. fathollahi

in this research, hydraulic and sorption behavior of geosynthetic clay liners (gcls) withordinary and modified clay exposed to crude oil were studied. both modified and ordinary bentonites wereinvestigated to evaluate crude oil adsorption efficiency on the liners. because soil permeability exposed tocrude oil is a major parameter in measuring the contaminants migration in soils, the permeabilit...

Journal: :journal of nanostructures 2012
m. jafar-tafreshi f. bustanafruz m. fazli

aluminum sulfate nano structures have been prepared by solution combustion synthesis using aluminum nitrate nonahydrate (al(no3)3.9h2o) and ammonium sulfate ((nh4)2so4). the resultant aluminum sulfate nano structures were calcined at different temperatures to study thermal  decomposition of aluminum sulfate. the crystallinity and phase of  the as-synthesized and calcined samples were characteri...

2010
Katharina Fucke

A review. Diffraction methods are a powerful tool to investigate the crystal structure of organic compounds in general and their hydrates in particular. The laboratory standard technique of single crystal X-ray diffraction gives information about the molecular conformation, packing and hydrogen bonding in the crystal structure, while powder X-ray diffraction on bulk material can trace hydration...

1998
Jianshu Cao Kent R. Wilson

Time-resolved X-ray diffraction patterns can be inverted to obtain photoinduced dynamics without resorting to additional and often unknown information (e.g., potential energy surfaces), as required in optical probe experiments. In order to interpret ultrafast X-ray diffraction measurements, we consider several time scales in X-ray experiments involving elastic versus inelastic scattering, quant...

Journal: :Physics in medicine and biology 1997
D Chapman W Thomlinson R E Johnston D Washburn E Pisano N Gmür Z Zhong R Menk F Arfelli D Sayers

Diffraction enhanced imaging is a new x-ray radiographic imaging modality using monochromatic x-rays from a synchrotron which produces images of thick absorbing objects that are almost completely free of scatter. They show dramatically improved contrast over standard imaging applied to the same phantom. The contrast is based not only on attenuation but also the refraction and diffraction proper...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید