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HIGH STRAIN RATE SUPERPLASTICITY IN A SiC_w/2.2.Al COMPOSITE MADE BY SQUEEZE CASTING

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Acta metallurgica Sinica(English Letters) 1998年第4期11卷 275-280页

作者： X.J.Xu D. Zhang Z.L. Shi C.Z.Zhao and R.J. Wu (state key {2. of metal Matrir Composites, Shanghai Jiaotong university, Shanghai 2.0030, china) Shanghai Jiaotong Univ Shanghai China

In this paper,the superplastic characteristics of the beta-SiC whisker reinforced 2.2.aluminum composite, fabricated by squeeze casting and hot-rolling after extrusion were investigated. The compsite had a fine grain size of about 2.m, and exhibited a strain rate sensitivity of about 0.35 and a maximum elongation of 350% at an initial strain rate of 1.1×10-1s-1 at 803K. In addition, the superplastic deformation mechanisme of the composite were also examined.

关键词： high strain rate superplasticity aluminum matrix composite squeeze casting

H_2.production with low CO selectivity from photocatalytic reforming of glucose on metal/TiO_2.catalysts

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Science china Chemistry 2008年第2期51卷 97-100页

作者： WU GuoPeng1,2. CHEN Tao2. ZHOU GuoHua 2. ZONG Xu2.& LI Can2.1 laboratory of Plasma Physical Chemistry, Dalian university of Technology, Dalian 11602., {2. 2.state key laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 11602., {2. laboratory of Plasma Physical Chemistry Dalian University of Technology Dalian China state key {2. of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian China

H2.with low CO concentration is produced via photocatalytic reforming of glucose (as a representative of biomass component) on metal/TiO2.catalyst (metals: Pt, Rh, Ru, Ir, Au, Ni, Cu). It is shown that the loaded metals generally enhance the rate of H2.production, while they depress the CO selectivity. Both H2.production and CO selectivity are strongly dependent on the kind of deposited metals on TiO2. For example, Rh/TiO2.catalyst is found to be most active for H2.production while with the most extremely low CO concentration from the photocatalytic reforming of glucose.

关键词： photocatalysis H2 production CO selectivity glucose metal (Rh Pt Ru Ir Au Cu or Ni)/TiO2

Synthesis and High Pressure Study on Ca_(1-x)Ln_xSiO_3

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Journal of Materials Science & Technology 1995年第4期11卷 307-309页

作者： Jinghai YANG Juyuan ZHANG Yizhi GENG (Institute of Solid state Physics, Siping Normal College, Siping, 136000, china)Bin YAO (state key Lab. for RSA, Institute of metal research, Chinese Academy of Sciences, Shenyang, 110015, china) Siping Normal Coll Siping China

In this paper, for the first time, Ca1-xLnxSiO3 (Ln=Y. La, x=0.1, 0.2. was synthesized with three methods of high temperature (HT) under atmospheric pressure (AP), high temperature (HT) combined with high pressure (HP) and sol-gel method. The sample obtained at the stable range of 4.3-5.0 GPa pressure and 1050-1100℃ temperature with HT and HP method has a cubic perovskite structure, which has the minimum lattice parameter of 0.3535 nm so far,the sample with triclinic structure was obtained by sintering at atmosphere, and the sample synthesized with sol-gel method has monoclinic structure. SEM analysis shows that rare earth ions take the lattice site of Ca, but the distribution of rare earth ions in the samples synthesized with HT and HP is not homogeneous.

关键词： Synthesis and High Pressure Study on Ca La SiO x)LnxSiO3

The crystal structure of a novel basket binuclear silver (Ⅰ) cryptate

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Chinese Journal of Chemistry 1994年第2期12卷 190-192页

作者： YU, Shu-Yan LUO, Qin-Hui SHEN, Meng-Chang ZHANG, Zheng Coordination Chemistry state key {2., nanjing university, nanjing, Jiangsu 2.0008, chinaHUANG, Xiao-Ying WU, Qiang-JinFuzhou state key {2. of Structural Chemistry, Fuzhou, Fujian 350002. china

The metal complexes of polyaza cryptand have attracted much attentionowing to their special structure, unusual photo-chemical, electrical and catalyticproperties. Recently, Lehn and Nelson synthesized successively a series ofcryptands and crypatates with high yield by (2.3) schiff-base condensation of tris(2.aminoethyl)amine and aryl dialdehyde. But so far, little work about the analogueswith larger cavities and flexible chains condensed by tris (3-aminopropyl) amine (abbr.

关键词： Silver cryptate binuclear crystal structure basket-type.

Adsorption and corrosion inhibition behavior of imidazole on cobalt electrodes studied by SERS and electrochemical methods

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Science china Chemistry 2005年第6期48卷 497-503页

作者： GU Wei1, LIU Guokun2. REN Bin2. WU Deyin2. GU Renao1 & TIAN Zhongqun2.1. Department of Chemistry, College of Chemistry and Chemical Engineering, Suzhou university, Suzhou 2.5006, china 2. {2. key laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen university, Xiamen 361005, china Department of Chemistry College of Chemistry and Chemical Engineering Suzhou University Suzhou China state key {2. for Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China

The interaction of imidazole with Co electrodes in an electrochemical system was studied by surface-enhanced Raman scattering (SERS) and electrochemical methods. The SER spectra of Co in an imidazole solution as a function of the applied potential were analyzed and the assignment of the Raman bands was made. It was found that there were three kinds of sur-face species on the Co surface in different potential regions and they were interchangeable de-pending on the potential. In a relatively negative potential region (?1.2.to ?0.9 V), imidazole was adsorbed on the surface and its orientation might change from a vertical configuration via the N-end of the pyridine ring to a tilted configuration via the C2.N3 double bond. In a more positive potential region (?0.8 to ?0.7 V), the SERS signal from the adsorbed imidazole weakened and finally disappeared, meanwhile the signal from the Co and imidazole complex strengthened gradually. At the open circuit potential (?0.6 V), we detected very strong bands from the Co ox-ides. By comparing the Tafel curves of the Co electrode in the solution without and with imidazole, we found that imidazole has a marked effect on the corrosion inhibition of the Co electrode. This result demonstrates that we may be able to reveal the complicated interaction of surface species with metal surface at the molecular level by combining the SERS and electrochemical methods.

关键词： cobalt, imidazole, inhibition, surface-enhanced Raman spectroscopy, Tafel plot.

Preparation of Ultrafine Si Powders from SiH_4 by Laser-induced Gas Phase Reaction

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Journal of Materials Science & Technology 1995年第1期11卷 71-74页

作者： Yali LI Yong LIANG Kesheng XIAO Fen ZHENG and Zhuangqi HU(state key {2. of Rapidly Solidified Nonequlibrium Alloys, Institute of metal research,Chinese Academy of Sciences, Shenyang, 110015, china)

High quality ultrafine Si powders have been synthesized from SiH4 by laser induced gas phase reaction. The powders prduced under different synthesis conditions have mean particle size of 10-12.nm in diam. with narrow particle size distribution, and free of hard *** powders are polycrystalline with the ratio of mean grain to particle diameter being between 0.3-0.7. The size of the powder increases with increasing laser power and reaction pressure,but decreases with increasing silane gas flow rate and the addition of Ar diluent. Grain sizes drop distinctly with the rise of the addition of Ar gas and laser power, but change little with the gas flow rate and reaction temperature. The formation of Si particles under different synthesis conditions is discussed

关键词： Si Preparation of Ultrafine Si Powders from SiH4 by Laser-induced Gas Phase Reaction Figure

Fatigue Crack Propagation Behavior of TiNi_(50.6)Shape Memory Alloy

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Journal of Materials Science & Technology 2001年第4期17卷 403-408页

作者： Guangbin RAO, Jianqiu WANG, We KE and Enhou HAN The state key {2. of Corrosion and Protection, Institute of M-tal research, Chinese Academy of Sciences,Shenyang 110016, china Inst. of metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The fatigue crack propagation behavior of TiNi50.6 shape memory alloy was studied. The ex- periment results showed that the crack propagation properties of this alloy display difference and similarity in comparison with common metallic materials. Because of the stress concentra- tion there was stress induced martensite transformation (SIMT) near the crack tip though the nominal stress was lower than the threshold stress of SIMT. The position and the amount of SIMT was in situ observed by a quester remote measurement system (QRMS). The observation results showed that the position of SIMT was beside the crack tip and was not in the plastic zone of common metallic materials (in front of the crack tip). The SIMT zone at an angle of about 45°to the direction of the crack propagation, like a butterfly,appeared in the loading process, disappeared in the unloading process and grew larger with the increase of K. The crack propagation rate(da/dN) followed the linear law in lg-lg plot. Observation of the crack surface showed fatigue striation clearly. The relationship between the site and the size of the plastic zone and the SIMT zone is discussed and a model is given to explain both the similarity and the difference of the crack propagation property of TiNi50.6 to common metal materials.

关键词： Fatigue Crack Propagation Behavior of TiNi Shape Memory Alloy

Microstructure and Phase Stability of Plasma Sprayed Sc_2._3-Y_2._3-ZrO_2.TBCs

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稀有金属材料与工程 2011年第S4期40卷 151-154页

作者： Li Q L1,Liu H F1,2.Yang W H1,Li S Q1,Chen H J1,31National key laboratory of Science and Technology on Power Beam Processes,Beijing Aeronautical Manufacturing Technology {2. Institute,Beijing 10002.,china 2.4} key laboratory of Powder metallurgy,Central South university,Changsha 410083,china 3state key laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan university of Technology,Wuhan 430063, china. Beijing Aeronaut Mfg Technol Res Inst Natl Key Lab Sci & Technol Power Beam Proc Beijing 100024 Peoples R China Cent S Univ State Key Lab Powder Met Changsha 410083 Peoples R China Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430063 Peoples R China

Scandia,yttria-stabilized zirconia (Sc2.3-Y2.3-ZrO2. powder for plasma spraying was synthesized by chemical co-precipitation *** morphology and phase stability of plasma sprayed 6.8mol%Sc2.3-1.2.ol%Y2.3-ZrO2.thermal barrier coatings (TBCs) were *** of the coatings were heated at 1400℃ for 500 hours and then examined by X-ray *** was found that the Sc2.3-Y2.3-ZrO2.coatings showed excellent phase stability to retain single tetragonal t' phase structure and did not undergo a tetragonal-to-monoclinic phase transition upon cooling.

关键词： thermal barrier coatings Scandia yttria-stabilized zirconia microstructure phase stability

MODELING AND INTEGRATED CONTROL FOR A metal PUSHING BELT CONTINUOUSLY VARIABLE TRANSMISSION SYSTEM

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Chinese Journal of Mechanical Engineering 2001年第4期14卷 336-341页

作者： Hu Jianjun, Qin Datong, Sun Dongye (state key {2. of Mechanical Transmission,Chongqing university) 重庆大学机械传动国家重点实验室重庆

By the bond graph theory,a bond graph analysis model of continuously variable transmission is established On the basis of improving the ratio change response and reducing the engine torque response lag in normal control,a new synthetic control algorithm is developed By analyzing the engine driving torque characteristics and the transmission inertia torque while ratio is changed under transient condition,the compensation value for engine driving torque is presented The simulation result shows that by this compensation control algorithm the engine torque response lag can be reduced and the driving torque response can be improved effectively.

关键词： Continuously variable transmission Modeling Control