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991.
Keying Guo Zhifeng Liu Yun Wang Yufeng Zhao Yuchen Xiao Jianhua Han Yajun Li Bo Wang Ting Cui 《International Journal of Hydrogen Energy》2014
The ZnO/SrTiO3 nanomaterials were fabricated by a chemical conversion hydrothermal method in order to utilize the high electron transfer rate of one-dimensional ZnO nanorods and photocatalytic activity of SrTiO3. The technological parameters, such as TiO2 sol concentration, TiO2 sol dipping cycle, Sr(NO3)2 concentration and reaction temperature, were investigated in the synthetic process and the reaction mechanism of the ZnO/SrTiO3 nanomaterials was proposed. A photocurrent density of 7.53 mA/cm2 was obtained for the as-prepared ZnO/SrTiO3 photocatalyst, attributed to its improved absorption spectrum and appropriate nanostructure, which indicates a potential application in photoelectrochemical water splitting. 相似文献
992.
Baoling Cui Desheng Chen Canfei Wang Zuchao Zhu Yingzi Jin Yuzhen Jin 《热科学学报(英文版)》2013,22(6):586-591
To investigate the influence of impeller type on the performance and inner flow of centrifugal pump, the numeri- cal simulation and experimental research were carried out on the same centrifugal pump with straight-blade and curved-blade open impeller. Based on SIMPLEC algorithm, time-averaged N-S equation and the standard k-e turbulence model, the numerical results are obtained. The pressure distribution in the different type impellers is uniform, while the low pressure area in straight-blade inlet is larger. The vortexes in the passage of impeller exist in both cases. Relative to curved-blade impeller, there are larger vortexes in most of the flow passages except the passage near the tongue in straight-blade impeller. Also some small backflow regions are found at the blade inlet of two impellers. The characteristic curves achieved by numerical simulation basieaUy agree with those by experiment, and straight-blade open impeller centrifugal pump has a better hydraulic performance. 相似文献
993.
Xiaofeng Cui Guiyuan Jiang Ming Zhu Zhen Zhao Luchao Du Yuxiang Weng Chunming Xu Dekai Zhang Quanlai Zhang Yuechang Wei Aijun Duan Jian Liu Jinsen Gao 《International Journal of Hydrogen Energy》2013
Solar driven semiconductor photocatalytic water splitting to produce hydrogen is an extremely charming process by storing photon energy in chemical bonds. In the present study, composite semiconductor TiO2/CdS was structured into uniform and porous double-shelled hollow sphere with cocatalyst platinum selectively loaded onto the internal wall. The SEM, TEM, STEM, XRD, BET and EDS elemental distribution etc. were employed to evidence the formation of the targeted photocatalyst. It was demonstrated that the material has a high efficiency of visible-light-driven hydrogen evolution (296 μmol·h−1/10 mg) with an apparent quantum efficiency (QE) of 14.5% at wavelength of 420 nm. Comparative experiment analysis and time-resolved infrared absorption study suggested that the high photocatalytic activity of the catalyst is attributed to the vectorial electron transfer (CdS → TiO2 → Pt) and the spatial separation of reduction and oxidation active surfaces achieved by the special morphology. 相似文献
994.
Zhe Zhao Li Liu Xiaomin Zhang Weiming Wu Baofeng Tu Daan Cui Dingrong Ou Mojie Cheng 《International Journal of Hydrogen Energy》2013
High- and low- temperature behaviors of La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) cathode for solid oxide fuel cells operating under CO2/H2O-containing atmosphere are investigated. LSCF shows different stability against CO2 and H2O at high and low temperature. LSCF has excellent electrochemical performance and high stability against the corrosion of CO2 and H2O at 750 °C due to weak reactivity of LSCF with CO2. LSCF shows a serious degradation at 600 °C under operation with O2–CO2(2.83%)–H2O(2.64%), which is ascribed to the impeded oxygen activation and oxygen surface diffusion by surface carbonates and SrCO3 phases on LSCF surface. Under CO2(5%)–H2O(2.81%)–He, LSCF reacts with CO2 to yield SrCO3 phases in 400–680 °C, and H2O aggravates the chemical reaction between CO2 and LSCF. Taking into account of SrCO3 phase formation on LSCF, LSCF cathode is stable under operation with O2–CO2(2.83%)–H2O(2.64%) in 680–800 °C, whereas it is unstable below 680 °C. LSCF can be subject to degradation caused by CO2 and H2O in air during long-term operation below 680 °C. 相似文献
995.
In this article, PtAg alloy nanoislands/graphene hybrid composites were prepared based on the self-organization of Au@PtAg nanorods on graphene sheets. Graphite oxides (GO) were prepared and separated to individual sheets using Hummer's method. Graphene nano-sheets were prepared by chemical reduction with hydrazine. The prepared PtAg alloy nanomaterial and the hybrid composites with graphene were characterized by SEM, TEM, and zeta potential measurements. It is confirmed that the prepared Au@PtAg alloy nanorods/graphene hybrid composites own good catalytic function for methanol electro-oxidation by cyclic voltammograms measurements, and exhibited higher catalytic activity and more stability than pure Au@Pt nanorods and Au@AgPt alloy nanorods. In conclusion, the prepared PtAg alloy nanoislands/graphene hybrid composites own high stability and catalytic activity in methanol electro-oxidation, so that it is one kind of high-performance catalyst, and has great potential in applications such as methanol fuel cells in near future. 相似文献
996.
997.
新型厌氧反应器COD去除影响因素研究 总被引:3,自引:0,他引:3
以模拟高浓度有机废水为研究对象,采用新型厌氧反应器对COD去除影响因素进行了为期4个月的试验研究,考察了污泥负荷、水力停留时间(HRT)、容积负荷、进水COD、VFA、出水SS等因素对COD去除的影响。结果表明,影响COD去除的主要因素是污泥负荷、HRT和容积负荷,次要因素是进水COD、VFA和出水SS,当反应器内COD污泥负荷在0.297 2~0.464 7 kg.kg-1.d-1之间、HRT=7 h时,COD的去除效率维持在72%~90%。 相似文献
998.
Shu-lin Xiao Xu Du Li Qin Cui-hong He Guang-hua Cui 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(6):1384-1390
Two one-dimensional Cd(II) coordination polymers constructed by ribbon-like molecules, {[Cd(L1)2(NO3)]·NO3} n (1) (L1 = 1,3-bis(5,6-dimethylbenzimidazol-1-yl)benzene) and [Cd(L2)2(NO3)2] n (2) (L2 = 1,3-bis(benzimidazol-1-yl)benzene) have been obtained through assembly of the two structurally similar flexible bis(benzimidazole)-based ligands and cadmium nitrate tetrahydrate. The cadmium(II) centers display different coordination environments with trigonal-bipyramidal geometry in 1, and a octahedral geometry in 2. Weak C–H···O interactions in 1 result in a two-dimensional supramolecular layer; two π–π interactions are present in 2 forming a three-dimensional supramolecular network structure. The solid state fluorescence properties of 1 and 2 were investigated. 相似文献
999.
以溴碳苯丙乳液为基料,配以聚磷酸铵、三聚氰胺、季戊四醇等助剂,配制了超薄型钢结构防火涂料;解决了现有钢结构防火涂料阻燃时效短的弊端,并对基料的阻燃机理进行了简单的探讨。自制超薄型钢结构防火涂料的各项技术指标均达到或超过了《钢结构防火涂料通用技术条件》中规定的指标。 相似文献
1000.