In recent years, the time-resolved X-ray diffraction technique has been established as an excellent tool for studying reaction dynamics and protein structural transitions with the aid of 100 ps X-ray pulses generated from third-generation synchrotrons. The forthcoming advent of the X-ray free-electron laser (XFEL) will bring a substantial improvement in pulse duration, photon flux and coherence...

X-ray Diffraction: A Practical Approach, C. Suryanarayana and M. Grant Norton, 1998. Plenum Press, New York and London. xiii + 273 pages. (hardback, $49.50, U.S. and Canada; $59.40, elsewhere).It is the aim of this text to teach undergraduates majoring in materials science the use of powder X-ray diffraction for materials characterization. Since it does not treat X-ray diffraction and crystallo...

Light microscopy has greatly advanced our understanding of nature. The achievable resolution, however, is limited by optical wavelengths to approximately 200 nm. By using imaging and labeling technologies, resolutions beyond the diffraction limit can be achieved for specialized specimens with techniques such as near-field scanning optical microscopy, stimulated emission depletion microscopy, an...

Fritillaria is a traditional Chinese herbal medicine for anti-tussive and expectorant use in China and some other Asian countries. The Fritillaria Chinese medicine material derived from different geographical origins is always difficult to discriminate each other. The objective of the study is to develop a nondestructive and simple method to identify five Fritillaria Chinese materia medica such...

Abstract: Previous studies have shown that X-rays are produced by electrically accelerating electrons produced by thermionic emission from a hot filament. The emitted electrons are then directed toward a crystal via collimator to study crystal properties. When the target material of the X-ray tube is bombarded with electrons accelerated from the cathode filament, two types of X-ray spectra are ...

“point” and “area” (originally film) detectors. The first X-ray diffraction experiment by Friedrich and Knipping [1] used film, but within the same year Bragg was using an ionization chamber mounted on a rotating arm [2]. The advantage of Bragg's X-ray detector was that it defined precisely the angle of the diffracted rays and, in general, gave more accurate intensity measurements. The advantag...

X-ray diffraction patterns from sperm-tail microtubules indicate that subunits with a 40 to 50 A packing diameter form filaments, alternately half-staggered, parallel to the tubule axis. A 12-or a 13-stranded structure fits best with the X-ray diagram. The strongest bonding is that between units within a longitudinal filament; the weaker lateral interactions are disrupted by drying. Microtubule...

in this research work the solid-solutions of (bi2o3)1-x (co2o3)x, [x= 0.05, 0.1] (1), (bi2o3)1-x (ho2o3) x, [x= 0.025, 0.05] (2), and (bi2o3)1-x-y (co2o3)x (ho2o3)y, [x=0.05] ; [y= 0.01, 0.02] (3) have been synthesized  using sol-gel method. the effects of transition metal oxides doping on the crystallization and phase transition of the bi2o3 were discussed by x-ray diffraction (xrd). the xrd p...

that particles are of less than 100nm in diameter called nano particles (nps) and there are in the world naturally like volcanic activity. in the present investigation a new mixed halomercurate nano particle compound was synthesised and characterized. triphenylphosphonium trichloromercorate (ii) [p(c6h5)3h]+[hgcl3]- nanoparticle was synthesi -zed by using triphenylphosphonium chloride reaction ...