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Photodecomposition of H_2. to H_2.over Cd_xZn_(1-x)S composite photocatalysts

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Rare Metals 2009年第2期28卷 137-141页

作者： Bai, Xuefeng Wu, Dan Wang, Peng School of Municipal and environmental engineering Harbin Institute of Technology Harbin 150090 China Heilongjiang institute of Petrochemistry Harbin 150040 China School of Chemistry and Material Science Heilongjiang University Harbin 150080 China

A series of CdxZn1-xS (x = 0.1-0.9) photocatalysts were prepared by coprecipitation. They could form solid solution semiconductors with hexagonal phase in agreement with pure CdS by characterization of XRD. The photophysical properties of CdxZn1-xS photocatalysts were measured by UV-Vis diffuse reflectance spectrum and surface photovoltage spectroscopy (SPS). The band gap energy gradually reduced with the increasing of x value in CdxZn1-xS,and when x = 0.7,the Cd0.7Zn0.3S photocatalyst had the strongest sur...

关键词： hydrogen production photodecomposition composite photocatalyst solid solution semiconductor

Microstructure and Tensile Properties of Yttria Coated-Alumina Particulates Reinforced Aluminum Matrix Composites

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Journal of Materials Science & technology 2005年第1期21卷 68-70页

作者： Zhiqiang YU, Gaohui WU, Longtao JIANG and Dongli SUNSchool of Materials Science and engineering, harbin institute of technology,{2., chinaPresent address: department of Materials Science, Fudan University, Shanghai 2.0433, chinaPh.D., to Sch. of Mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

The liquid-phase coating method was used to deposit Y2.3 ceramic on the surface of α-Al2.3. The coated-Al2.3p/6061AI composites were produced using squeeze casting technology. The microstructure and tensile properties of the composites were analysed and studied. The results showed that the coated AI2.3 particles are able to disperse homogeneously in the aluminum liquid. The microstructure of the composites is more even in comparison with that of as-received powders. The tensile testing indicated that mechanical properties of the coated-AI2.3p/6061AI composites are better than those of uncoated particles. In the composite with 30% volume fraction, the tensile strength, yield strength as well as elongation is increased by 2..8%, 38.4% and 10.3%, respectively. The SEM analysis of fracture indicated that the dimples of the coated-Al2.3p/6061Al composites are more even.

关键词： Submicron alumina powders Rare-earth oxide coating Microstructure Mechanical properties Aluminum matrix composite

Self-healing of engineered cementitious composites at simulated summer conditions

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Rare Metals 2007年第S1期26卷 267-273页

作者： LEPECH M.D department of Civil and environmental {2. University of MichiganAnn ArborMI 48109-2125USA

Self-healing of engineered cementitious composites(ECC) subjected to a cyclic drying and wetting regime simulated summer outdoor environment was investigated in this *** tension tests were used to generate multiple cracks in ECC specimens deformed to varying tensile *** quantify self-healing,resonant frequency measurements were conducted throughout drying-wetting cycles followed by tensile testing of self-healing ECC *** was found that through self-healing the resonant frequency of ECC can recover 81% to 90% of initial values while showing a distinct rebound in stiffness of cracked ECC after *** specimens pre-loaded to high levels of strain between 2. and 3%,the tensile strain after self-healing can recover from 1.8% to 2.2..Also,the effects of temperature during cyclic regime can lead to an increase in the ultimate strength of the material while slightly decreasing the strain-hardening capacity of ECC due to further hydration of unreacted cement and fly ash.

关键词： ECC self-healing cyclic drying and wetting resonance frequency tensile stress tensile strain

Novel Harmonic Free Single Phase Variable Inductor Based on Active Power Filter Strategy

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Novel Harmonic Free Single Phase Variable Inductor Based on ...

Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

CES/IEEE 5th International Power Electronics and Motion Control Conference

作者： Mu Xianmin Wang Jianze Ji Yanchao Wei Xiaoxia and Fu Xiangyun Electrical engineering department of{2. harbin 150001 Heilongjiang P.R.china Electrical engineering department Harbin Institute of Technology Harbin Heilongjiang China

ISBN: (纸本)1424404487;9781424404483

＜正＞This paper presents a variable inductor for single phase system which employs a new control method based on active power filter schemes. The novel variable inductor combines an active power filter circuit and a control circuit. The active power filter circuit is based on a single phase inverter with four controllable switches, a standard H-bridge inverter. The AC side of the inverter is connected to an aid harmonic elimination winding of the variable inductor. Its DC side is connected to a filter capacitor and the secondary winding of variable inductor through the control circuit based on BUCK circuit. The inverter switches are controlled to shape the current through the filter inductor such that the primary current is in the same shape as the input voltage, and in the same time supply the active power consumer of control circuit. The controller is based on a conceptually simple control scheme, the energy balance concept. The advantages of new variable inductor are simplicity of control circuits, low cost and good response. In theory, the harmonic current component of the variable inductor is zero. The feasibility of this theory is verified by using Matlab/Simulink simulation results.

关键词： variable inductor harmonic elimination PWM converter energy balance

来源： cnki会议评论

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cnki会议

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Science china(Technological Sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3, LOU Decheng1, GAO Zhanjun4, LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3 & MA Mingzhen1,2.1. Key Laboratory of Metastable Materials Science & technology of Hebei, Yanshan University, Qinhuangdao 066004, china 2. National Key Laboratory for Precision Hot Processing of Metals,{2., harbin 150001, china 3. College of Mechanical engineering, Yanshan University, Qinhuangdao 066004, china 4. Chinese Academy of engineering, Beijing 100038, china 1. Key Laboratory of Metastable Materials Science & technology of Hebei Yanshan University 066004 Qinhuangdao China 2. College of Mechanical engineering Yanshan University 066004 Qinhuangdao China 3. Chinese Academy of engineering 100038 Beijing China 4. National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology 150001 Harbin China

Mechanical properties of the Zr41Ti14Cu12.5Ni10Be2..5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-32.0 machine at 345 and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr41Ti14Cu12.5Ni10Be2..5 bulk amorphous alloy, mechanical properties, compressive deformation.

Arylamine N-acetyltransferases: a new inhibitor of apoptosis in HepG2.cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第9期9卷 701-706页

作者： Yu-bin JI1,2. Shi-yong GAO1,2.(1Postdoctoral Research Station of the institute of Materia Medica, Center for Life Sciences and environmental Sciences, {2. University of Commerce, {2. 150076, china) (2.OE engineering Research Center of Natural Anticancer Drugs, {2. University of Commerce, {2. 150076, china) Postdoctoral Research Station of the institute of Materia Medica Center for Life Sciences and Environmental Sciences Harbin University of Commerce Harbin 150076 China MOE engineering Research Center of Natural Anticancer Drugs Harbin University

Objective: To explore how arylamine N-acetyltransferases (NATs) is related to cell apoptosis. Methods: NAT activity in apoptotic HepG2.cells was measured using high performance liquid chromatography (HPLC); the apoptosis rate of HepG2.cells acted upon by an NAT inhibitor was measured using flow cytometry. Results: NAT activity was lowered in apoptotic HepG2.cells; apoptosis rate induced by camptothecin (CAM) increased after inhibition of NAT activity in HepG2.cells. Conclusion: NAT can inhibit apoptosis in HepG2.cells.

关键词： Arylamine N-acetyltransferases (NATs) Apoptosis HepG2 Camptothecin (CAM)

Performance prediction and flow analysis in the vaned distributor of a pump turbine under low flow rate in pump mode

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中国科学：技术科学英文版 2010年第12期53卷 3302-3309页

作者： YIN JunLian1, LIU JinTao1, WANG LeQin1, JIAO Lei1, WU DaZhuan1 & QIN DaQing2.1 institute of Chemical Machinery, department of Chemical and Biological {2., Zhejiang University, Hangzhou 31002., china 2.harbin institute of Large Electrical Machinery, harbin 150001, china 1. institute of Chemical Machinery Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China2. Harbin Institute of Large Electrical Machinery Harbin 150001 China

The main goal of this work is to investigate the possible different flow patterns existing in pump turbine under off-design conditions in pump mode. Numerical simulations by solving the Navier-Stokes equation, coupled with the "SST k-ω" turbulence model, were carried out. Flow characteristics were assumed to be stalled in the appropriate region of ?ow rate levels of Q/QD=0.15–0.61. The simulation result was compared with experimental data and they showed good agreement. Consequently, velocity fields in three axial locations in stay vanes and guide vanes were analysed in details. It was shown that "jet-wake" flow pattern exists near the band, which changes little in the whole shape with flow rate increasing; to the middle location of vanes, reverse flow begins to appear on the interface between the runner and guide vanes, which will disappear gradually as the flow rate increases; massive reverse flow is captured near the crown, whose intensity will be weakened as the flow rate increases. Ultimately, it was found that the special head-flow profile can be ascribed to the special hydraulic loss characteristics of the stay vanes and guide vanes.

关键词： pump turbine flow simulation stalled flow guide vane

STUDY ON COATING MECHANISM OF DIAMOND FILM ON CUTTING TOOL AND ITS APPLICATION

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Chinese Journal of Mechanical engineering 2000年第1期13卷 25-29页

作者： Yao Yingxue Zhang Hongzhi Huang Shutao Yuan Zhejun (department of Mechanical engineering,{2.) 哈尔滨工业大学黑龙江哈尔滨

The deposition mechanism of diamond film on cutting tools and the state of the interface between film and substrate are studied theoretically and experimentally. Methods for controlling diamond crystalline state and improving adhesion of diamond films to substrates are proposed to improve the quality of diamond-coated tools. Experiments are performed by cutting Al-Si18% alloy and SiCp/Al composite with diamond coated tool. The results indicate that the life of coated tools is 90 times higher than that of non-coated tools. Wear mechanism of diamond-coated tools is also studied.

关键词： Coating tool Diamond Chemical vapor deposition

KEYHOLE IMAGE PROCESSING OF VARIABLE POLARITY PLASMA ARC WELDING BASED ON WAVELET TRANSFORM

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Chinese Journal of Mechanical engineering 2001年第1期14卷 62-66+73页

作者： Liu Zhonghua Wang Qilong Zhu Jiaqi Welding department, harbin institute of technology 哈尔滨工业大学黑龙江哈尔滨

In order to realize the feedback control for variable polarity plasma arc welding (VPPAW) formation in the welding process, the geometrical sizes of the keyhole image must be extracted. With the properties of multiscale edge through the wavelet theory, the edge points were detected by getting the maximum modules of the gradient vector in the dircetion towards which the gradient vector points in the image plane. At coarse scales, the local maxima of modules have different positions and only detected the sharp edge. At fine scale, there are many maxima created by the image noise. The best scale where the edges are well discriminated from noises is discussed by the multiscale transform. At last, a new method of peak analysis for threshold selection is provided. It is based on the wavelet transform which provides a multiscale analysis of the information of the histogram. Many experiments show these ways are effective for the keyhole image to get the geometry parameters of the keyhole in the real time VPPAW image processing.

关键词： PAW Variable polarity Keyhole Image