Search

SrWO4 octahedrons, flowers, bundles, ellipsoids and dendrites had been successfully synthesized via surfactant-assisted method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photo-luminescent spectra techniques (PL) and fourier transrform infrared spectrometer (FTIR). By through various comparison experiments, it can be found that some related experimental parameters including the reagent concentration, [Sr2+]/[WO42-] molar ratio (R), aging temperature and the pH value had great influences on morphology of the products.

Ca(MoO4)x(WO4)(1-x) solid solution microcrystallines were synthesized by hydrothermal method at 120 ℃; the crystal structure, surface morphology and room temperature photoluminescence properties of the as-synthesized microcrystallines were investigated by through X-ray diffraction (XRD), scanning electron micrograph (SEM), Fourier transform infrared spectroscopy (FT-IR) and fluorescence analysis (FA), respectively. Our results show that the obtained Ca(MoO4)x(WO4)(1-x)microcrystallines are single-phase scheelite structure with tetragonal symmetry. The grain size of the Ca(MoO4)x(WO4)(1-x) microcrystallines gradually increases with the increasing x (except x=0) and their agglomeration also becomes serious with x increasing. Under excited by 245 nm or 280 nm ultraviolet light (UV-light) at room temperature, the emission spectra of the Ca(MoO4)x(WO4)(1-x) microcrystallines vary slightly from 410nm to 490nm with increasing x. Whereas the emission intensity of Ca(MoO4)x(WO4)(1-x) microcrystallines changed markedly, and it increases with the increasing x (x＞0).

In-situ Al3Ti /A356 composites were synthesized by direct melt reaction method in Al-K2TiF6 system. The preparation techniques was discussed and the effects of Si, Mg, La (0.30%), Ce (0.30%) and multiple rare earth (0.15% La + 0.15%Ce) addition on microstructures of Al3Ti /A356 composites were investigated by X-ray diffraction and scanning electron microscope. The results show that the morphology and size of Al3Ti reinforcement are influenced significantly by Si, Mg and the optimal preparation process is composition with latter Si, Mg alloying. The Al3Ti precipitations during solidification process are restrained by 0.30% La addition or 0.30% Ce addition and lead in the uniform of Al3Ti size and morphology. The radial growth of Al3Ti is strongly restrained by rare earth composite addition, and the main morphology is slender-spherical like.

Along with the increasing number of Chinese automobiles in cities, the vehicle management becomes a difficult issue. The effective management on vehicle is to identify the vehicle. RFID technology can be used for the access control management, which can serve an effective way to identify the vehicles, making access control management of the security protection more effective and intellective[1] . Access Control System based on RFID protocol is proposed, and then introduces a model of system and gives a brief description of each component of the model, A detailed explanation about the implementation of each model is given.