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In2BiTaO7 was synthesized using the solid-state reaction method and its photocatalytic properties were investigated. The results of powder X-ray diffraction (XRD) indicated that the compound crystallizes in the pyrochlore-type structure, cubic system with space group Fd-3m. The lattice parameter is 10.6972(1) ?. In addition, the compound shows strong optical absorption in the visible region (λ > 420 nm) and the band gap of In2BiTaO7 was estimated to be about 2.47 eV. For the photocatalytic reaction, H2 or O2 evolution was observed from CH3OH/H2O or AgNO3 solution respectively with In2BiTaO7 as the photocatalyst under visible light irradiation, indicating that In2BiTaO7 is responsive to visible light for splitting water. Furthermore, the catalyst remained photoactive in the wavelength range up to 510 nm. Photocatalytic degradation of methylene blue (MB) dye over the compound was further investigated under visible light irradiation. The results showed that complete removal of aqueous MB could be achieved after irradiation for 135 min over In2BiTaO7. Furthermore, under visible light irradiation In2BiTaO7 showed markedly higher catalytic activity compared to P-25 for MB photocatalytic degradation.  相似文献   
34.
用氨基三氮唑硫代丙酸乙酯与取代苯甲醛反应,合成了6个新型的5-氨基-1H-1,2,4-三氮唑-3-硫代-2′-丙酸乙酯类Schiff碱,其结构经^1H NMR,IR,MS和元素分析表征。  相似文献   
35.
Carbon-supported catalysts were phosphonated using 2-aminoethylphosphonic acid, and the resulting catalysts with largely enhanced proton conductivity performed substantially better than the untreated counterparts in proton-exchange membrane fuel cells.  相似文献   
36.
用抗坏血酸将Ce(Ⅳ)还原为Ce(Ⅲ),以多聚磷酸钠作为增强剂,建立了铈的流动注射荧光分析法,考查了各种因素对测定Ce的影响.此方法线性范围为2.0×10-9~1.2×10-8 g·ml-1.采用流动注射微柱预分离富集测定了GBW07602标样和氨基酸微肥中的铈含量.测定结果与推荐值有良好的一致性.  相似文献   
37.
The photoluminescence of Co-Al-layered double hydroxide   总被引:1,自引:0,他引:1  
We report a new optical behaviour of pure Co-Al-layered double hydroxide (LDH).It was found that the Co-Al-LDH sample could emit fluorescence without any fluorescent substances intercalated.Its excitation spectrum shows a maximum peak near the wavelength 370nm,the maximum emission peak appears at 430 nm and the photoluminescence colour of the Co-Al-LDH sample is blue.This new optical property will be expected to extend the potential applications of LDHs in optical materials field.  相似文献   
38.
Chemical processing in the stratospheres of the gas giants is driven by incident vacuum ultraviolet (VUV) light. Ethane is an important constituent in the atmospheres of the gas giants in our solar system. The present work describes translational spectroscopy studies of the VUV photochemistry of ethane using tuneable radiation in the wavelength range 112 ≤ λ ≤ 126 nm from a free electron laser and event-triggered, fast-framing, multi-mass imaging detection methods. Contributions from at least five primary photofragmentation pathways yielding CH2, CH3 and/or H atom products are demonstrated and interpreted in terms of unimolecular decay following rapid non-adiabatic coupling to the ground state potential energy surface. These data serve to highlight parallels with methane photochemistry and limitations in contemporary models of the photoinduced stratospheric chemistry of the gas giants. The work identifies additional photochemical reactions that require incorporation into next generation extraterrestrial atmospheric chemistry models which should help rationalise hitherto unexplained aspects of the atmospheric ethane/acetylene ratios revealed by the Cassini–Huygens fly-by of Jupiter.

The vacuum ultraviolet photodissociation dynamics of ethane provide clues for modelling the atmospheric chemistry of the gas giants.  相似文献   
39.
The enthalpy change of formation of the reaction of hydrous dysprosium chloride with ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phen?H2O) in absolute ethanol at 298.15 K has been determined as (-16.12 ± 0.05) kJ?mol-1 by a microcalormeter. Thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy), rate constant and kinetics parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of the reaction have also been calculated. The enthalpy change of the solid-phase reaction at 298.15 K has been obtained as (53.59 ± 0.29) kJ?molt-1 by a thermochemistry cycle. The values of the enthalpy change of formation both in liquid-phase and solid-phase reaction indicated that the complex could only be synthesized in liquid-phase reaction.  相似文献   
40.
胡艾希  陈平  袁帅  周勇 《合成化学》2002,10(4):333-334
室温下,6-甲氧基-2-丙酰基萘和1,3-二溴-5,5-二甲基海因的溴化反应在醇溶剂中,反应速度快、转化率高,生成5-溴-6-甲氧基-2-丙酰基萘的收率高(98.59%)。  相似文献   
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