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β-GaO films were grown on c-plane sapphire substrates at different substrate temperatures by metal-organic chemical vapor deposition. The effects of substrate temperature on transparence, optical band gap and photoluminescence of the films were studied systematically. With increasing the substrate temperature, the films structure was changed from amorphous to single orientation β-GaO. The β-GaO films exhibited excellent optical transparency in the ultraviolet and visible regions. The ultraviolet-blue photoluminescence was observed at room temperature. The temperature-dependent photoluminescence was also carried out and the relative intensity of the blue emission with respect to the ultraviolet emission decreased with increasing the measured temperature. The origin of luminescence was discussed. [ABSTRACT FROM AUTHOR]

LiNH2 decomposes to NH3 rather than N2 and H2 because of a severe kinetic barrier in NHx (x = 1, 2) coupling. In the presence of Ru, however, a drastic enhancement in N2 and H2 formation is obtained, which enables the LiNH2–Ru composite to act as a highly active catalyst for NH3 decomposition. Experimental and theoretical investigations indicate that Li creates a NHx-rich environment and Ru mediates the electron transfer facilitating NHx coupling. A strategy in catalytic material design is thus proposed. [ABSTRACT FROM AUTHOR]

BaZnMoO:Eu (0.1 ≤ x ≤ 0.7) red phosphors were synthesized at the temperature of 800 °C by solid-state reaction method in air atmosphere. The structures of the phosphors were characterized by X-ray diffraction and Raman spectra. Photoluminescence (PL) spectra were also used to investigate the photoluminescent properties of the phosphors. The experimental results indicated that the introduction of Ba enhanced the emission at 615 nm. The different Ba/Zn ratios of the molybdate phosphors caused the corresponding changes of photoluminescent properties. The variation of photoluminescent intensity with Ba concentration as well as with different excitation wavelengths was discussed systematically. BaZnMoO:Eu phosphors with the optimal compositions of x = 0.5 exhibited satisfactory and excellent PL and the intensity of the emission at 615 nm was about three times stronger than that of ZnMoO:Eu, which could be applied as red-emitting phosphors excited by ultra-violet and blue chips in white light-emitting diodes. [ABSTRACT FROM AUTHOR]

Abstract: The SiO2/ZrO2 and ZrO2/SiO2 bilayer films with good optical characteristics were prepared on glass substrates by sol–gel dip-coating method. The nanostructures on surfaces of the SiO2 monolayer film and ZrO2/SiO2 bilayer film were observed distinctly. The bilayer films had high transparency throughout the visible wavelength range. Under the same annealing conditions, the different optical properties of SiO2/ZrO2 and ZrO2/SiO2 bilayer films were studied. And interlayer annealing influenced the transmittance of SiO2/ZrO2 bilayer films obviously. But it almost had no effect on ZrO2/SiO2 bilayer films. [Copyright &y& Elsevier]

Abstract: TiO2 pillared montmorillonite synthesized by microwave irradiation, exhibited good photocatalytic degradation performance of methyl orange, whose pseudo first order reaction rate constant was nearly four times than that of conventional method, because of its enhanced crystalline, preferred anatase phase and improved porosity performance, which were analysed by X-ray diffraction (XRD), far Fourier transform infrared ray spectroscopy (FTIR) and nitrogen adsorption isotherms. [Copyright &y& Elsevier]

In this study, a mixture of poly(vinyl alcohol) (PVA) and chitosan oligosaccharides (COS) was electrospun with silver nanoparticles (AgNPs) to produce fibrous mats for use in wound healing. The AgNPs were reduced by COS prior to electrospinning or Ag(+) was reduced via ultraviolet irradiation in nanofibers. The morphologies of the PVA/COS/AgNO3 and PVA/COS-AgNP nanofibers were analyzed by scanning electron microscopy. Formation of the AgNPs was investigated by field emission transmission electron microscopy, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. We also evaluated the biocompatibility of the nanofibers, particularly their cytotoxicity to human skin fibroblasts and potential to cause primary skin irritation. The in vitro antibacterial activity and in vivo wound healing capacity of the nanofibers were also investigated. The nanofibers had a smooth surface with an average diameter of 130-192 nm. The diameters of the AgNPs were in the range of 15-22 nm. The nanofibers significantly inhibited growth of Escherichia coli and Staphylococcus aureus bacteria. PVA/COS-AgNP nanofibers accelerated the rate of wound healing over that of the control (gauze). The results of our in vitro and in vivo animal experiments suggest that PVA/COS-AgNP nanofibers should be of greater interest than PVA/COS/AgNO3 nanofibers for clinical use as a bioactive wound dressing.