We investigated the structure of SiO2 glass up to 172 GPa using high-energy X-ray diffraction. The combination of a multichannel collimator with diamond anvil cells enabled the measurement of structural changes in silica glass with total X-ray diffraction to previously unachievable pressures. We show that SiO2 first undergoes a change in Si-O coordination number from fourfold to sixfold between...

introduction: the aim of this study was to compare the chemical compounds of white proroot mineral trioxide aggregate (wmta) hydrated at different ph environments. methods and materials: mixed samples of wmta were kept in acidic (ph=5.4), neutral (ph=7.4) and alkaline (ph=9.4) environments for 48 h. then, x-ray diffraction (xrd) analysis was performed for both hydrated and powder forms of wmta....

oxide nanoparticles can exhibit unique physical and chemical properties due to their limited size and a high density of corner or edge surface sites. in this study, mgo nanoparticle was synthesized using mg(ch3coo)2 and hexamethylenetetramine as starting materials. the structure and optical properties of these particles are investigated by using x-ray diffraction (xrd), scanning electron micros...

the magnetite (fe3o4) – agar nanocomposite was prepared by co-precipitation of fe (iii) and fe (ii) ions for the first time. the obtained samples were characterized by x-ray diffraction, fourier-transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. ft-ir results confirm the formation of fe3o4 nanoparticles in agar matrix. the xrd results revealed th...

A noniterative method for retrieving the phase of a wave field from a diffraction intensity measurement in a coherent wave field is proposed. In this method, the phase can be calculated from analytic equations based on the properties of entire functions by use of Fourier transforms. This method requires only a single measurement of the intensity of a diffracted wave through an array filter of r...

in recent years many research works have been carried out on anti-corrosive nanocomposites coatings containing mineral reinforcements. the most important criteria in these attempts are polymerization method and the type of matrix and reinforcement of nanocomposites. in this regard, the physical and mechanical properties of the polymers in which a small amount of filler is used can be improved. ...

Multiple-wave Diffraction Anomalous Fine Structure (MDAFS), a new method combining the X-ray multiple-wave diffraction with diffraction anomalous fine structure (DAFS) technique, provides the long-range order structure information by measuring the multiple-wave diffraction profiles in the vicinity of an absorption edge. The real part of dispersion correction and fine structure function can be o...

A new design for implementation of x-ray diffraction experiments is proposed. The exploitation of the imaging plate technique opens new possibilities to carry out diffraction experiments. The detector chamber in Debye–Scherrer geometry equipped with an image plate takes advantage of this technology such as high resolution, high sensitivity, linearity in intensity, and linearity over the detecto...