in this work, sol-gel processing was used to synthesize the fluorohydroxyapatite (nano-fha, ca10(po4)6(oh)2−xfx) nanopowders. the advantages of the sol-gel method over other methods are precise control of composition, low processing temperature, and better homogeneity. calcium nitrate tetrahydrate, phosphorous pentoxide and tetrabuthylammonium fluoride were used, respectively, as p, ca, and f p...

pure barium zirconate nanopowders were successfully prepared in wet-chemistry synthesismethod, using barium stearate and tetra-n-butyl zirconate as ba, zr sources and stearic acid ascomplexing reagent. the gel was calcined at 800 and 900 °c in air. results of thermal analysisare given, including both dtg and tg. fourier transform infrared spectrometry (ftir), x-raydiffraction (xrd), transmissio...

The study of crystals at atomic level by electrons - electron crystallography - is an important complement to X-ray crystallography. There are two main advantages of structure determinations by electron crystallography compared to X-ray diffraction: (i) crystals millions of times smaller than those needed for X-ray diffraction can be studied and (ii) the phases of the crystallographic structure...

X-ray diffraction was demonstrated from shock-compressed polycrystalline metals on nanosecond time scales. Laser ablation was used to induce shock waves in polycrystalline foils of Be, 25-125 microm thick. A second laser pulse was used to generate a plasma x-ray source by irradiation of a Ti foil. The x-ray source was collimated to produce a beam of controllable diameter, which was directed at ...

The effects of black tea polyphenol extract (BTPE) on the retrogradation of starches from different plant sources were studied using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). DSC analysis shows that the gelatinization temperature of maize starch and starches from different rice varieties increased with increasing BTPE level. After storage at 4 °C, BTPE at a concentrat...

X-ray diffraction patterns from two-dimensional (2-D) protein crystals obtained using femtosecond X-ray pulses from an X-ray free-electron laser (XFEL) are presented. To date, it has not been possible to acquire transmission X-ray diffraction patterns from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permit a new method ...

Amyloid fibril deposition is central to the pathology of Alzheimer's disease. X-ray diffraction from amyloid fibrils formed from full-length Abeta(1-40) and from a shorter fragment, Abeta(11-25), have revealed cross-beta diffraction fingerprints. Magnetic alignment of Abeta(11-25) amyloid fibrils gave a distinctive X-ray diffraction texture, allowing interpretation of the diffraction data and a...

A bone has a hierarchical structure as shown in Fig. 1 [1]. Macroscopic bone properties are dependent on the microstructure and properties of structural elements. The bone is a composite material that consists of hydroxyapatite particles in a matrix of collagen fiber. Borsato et al. [2] measured the strain of hydroxyapatite by X-ray diffraction and obtained clear evidence of the stress concentr...

We report the first image of an intact, frozen hydrated eukaryotic cell using x-ray diffraction microscopy, or coherent x-ray diffraction imaging. By plunge freezing the specimen in liquid ethane and maintaining it below -170 degrees C, artifacts due to dehydration, ice crystallization, and radiation damage are greatly reduced. In this example, coherent diffraction data using 520 eV x rays were...

A compact scanning force microscope has been developed for in situ combination with nanofocused X-ray diffraction techniques at third-generation synchrotron beamlines. Its capabilities are demonstrated on Au nano-islands grown on a sapphire substrate. The new in situ device allows for in situ imaging the sample topography and the crystallinity by recording simultaneously an atomic force microsc...