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The microstructures, phase transformations, mechanical properties and shape memory effect of Ti-20Zr-10Nb-xAl (x=1, 2, 3, 4 at%) alloys were investigated. The X-ray diffraction results show that the alloys are composed of a single martensitic α″-phase and that the corresponding unit cell volume decreases with increasing Al content. The reverse martensitic transformation start temperature ( A s ) of the Ti-20Zr-10Nb-Al alloy is 534 K and decreases with increasing Al content. The addition of Al results in solid solution strengthening and grain refinement strengthening, thus improving the mechanical properties and the shape memory effect of the Ti-20Zr-10 Nb-xAl alloys. The Ti-20Zr-10Nb-3Al alloy shows the greatest shape memory strain (3.2%) and the largest tensile strain (17.6%) as well as a very high tensile strength (886 MPa). [ABSTRACT FROM AUTHOR]

In order to prepare the PbTiO3 coating with high density and excellent piezoelectric properties on all kinds shape surface, the PbTiO3 coating was prepared by supersonic plasma spraying. The microstructure and mechanical properties were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectrograph (XPS). The dielectric constant and dissipation constant of the PbTiO3 coating were tested. The results show that the coating has a single ferroelectric phase with perovskite structure, and its surface is smooth and dense. In the course of spraying, about 50% PbTiO3 is decomposed into PbO and TiO2 at high temperature. The ferroelectric hysteresis is weak and the ferroelectric hysteresis loop is not completely closed, which indicates that the defects, such as pores and cracks, exist in the coating. Although the defects are inevitable, the PbTiO3 coating with ferroelectric and piezoelectric properties is successfully prepared. [ABSTRACT FROM AUTHOR]

Abstract: SiO2-coated Ca2BO3Cl:Eu2+ phosphors were prepared by the sol–gel method in order to enhance the chemical and thermal stabilities of Ca2BO3Cl:Eu2+ phosphor. The phase structures, microstructures and luminescence properties were studied by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectrometer, respectively. The emission intensity of SiO2-coated Ca2BO3Cl:Eu2+ phosphor decreased a little compared to that of the uncoated phosphor. The moisture resistances of the phosphors were comparatively examined by the aging treatment experiment in the water, and the thermal stability was studied by the temperature dependent photoluminescence spectra. The results indicated that SiO2 coating on the surface of the phosphor particles improved the moisture-resistance and thermal stability to a large extent. [Copyright &y& Elsevier]

Abstract: The structure of 20GaF3–15InF3 –20CdF2–15ZnF2–20PbF2–10SnF2 glass (GICZPS) was studied by EXAFS and XRD. The results indicate that Ga3+ is more stable than In3+ in the GICZPS glass network, and Zn2+ is the glass modifier, the coordination number of which is 6. [Copyright &y& Elsevier]

Abstract: One dimensional bifunctional magnetic-photocatalytic CNTs/Fe3O4–ZnO nanohybrids were synthesized by one-pot polyol sequential process. The as synthesized products were characterized by X-ray diffraction, Fourier transform infrared spectrometer, transmission electronic microscope, energy dispersive spectrometer, physical properties measurement system and UV–Vis absorption spectroscopy. The results exhibit the ZnO forms heterogenerously on the surface of CNTs/Fe3O4 and the nanohybrids display superparamagnetic behavior at room temperature. Photocatalytic studies verify the as-prepared sample have high photocatalytic activity toward the photodegradation of methyl orange in solution. In addition, the photocatalyst can be recycled using magnetic field and maintain high photocatalytic activity. [Copyright &y& Elsevier]

The porous Ag 3 PO 4 architectures (PAs) were synthesized by a facile self-sacrificial route through the simultaneous acid-etching and anion exchange reactions between Ag 2 CO 3 and H 3 PO 4 at room temperature. The resulting samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–vis diffuse reflectance spectroscopy. The Ag 3 PO 4 PAs exhibited superior photocatalytic activity for the degradation of methyl orange (MO) under visible light irradiation, which were much higher than that of solid Ag 3 PO 4 counterpart. This study could provide a general approach for the synthesis of other porous semiconductors from carbonate precursor. [ABSTRACT FROM AUTHOR]