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Comparison of Structure and Properties among Various PAN Fibers for Carbon Fibers

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Journal of materials science & Technology 2005年第3期21卷 376-380页

作者： Dongxin HE, Chengguo WANG, Yujun BAI and Bo ZHU college of materials science and engineering, Shandong university, Jinan 250061, china college of materials science and engineering Shandong University Jinan 250061 China

To find out the high-quality polyacrylonitrile (PAN) fibers, some differences are sought by comparing domestic PAN fibers with the foreign ones. X-ray diffractometer (XRD), transmission electron microscope (TEM), Fourier transform infrared (FT-IR) spectrometer, elemental analyzer, tensile-testing machine and high-temperature differential scanning calorimeter (DSC) are used to characterize the individual microstructure, chemical structure, elemental content, mechanical properties and thermal properties. It is found that high-quality PAN fibers have high density, lower titre, higher or adequate tensile strength, and they also have better conglomeration structure, smaller crystal dimension with dispersive distribution, less microvoids and flaws.

关键词： Polyacrylonitrile (PAN) fiber Carbon fiber Structure Properties

Interactions of particles with solidifying front in Al_2O_(3P) /Al Si composites

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中国有色金属学会会刊：英文版 1999年第3期9卷 524-529页

作者： Wu Shusen(吴树森), Huang Naiyu(黄乃瑜),An Ping(安萍) college of materials science and engineering, Huazhong university of science and Technology, Wuhan 430074, P.R. china Huazhong Univ Sci & Technol Coll Mat Sci & Engn Wuhan 430074 Peoples R China

The behavior of ceramic particles at the solid/liquid interface and the distribution of particles in metallic matrix composites was studied with a zone unidirectional solidification method. Two kinds of partice dispersed composites, Al 2O 3P /Al 12.6%Si Sr and Al 2O 3P /Al 12.6%Si Sr Ca containing Al 2O 3 particles in volume fraction 2%～5% were used. In the Al 2O 3P /Al Si Sr composites, the particles were pushed by the solidifying front, and did not uniformly distribute in the solid. But in the Al 2O 3P /Al Si Sr Ca composites, the particles were engulfed by the solidifying front and uniformly distributed in the solid. The particles engulfing into the solid was realized only by Sr and Ca addition at the same time. As the interfacial energy between solid and particle was decreased in this case, the Al 2O 3 particles acted as the substrates of heterogeneous nucleation for the Si phases, which made the particles to be engulfed.

关键词： metallic matrix composites solidification particle size distributionDocument code: A

A new method to improve surface morphology of Ni-Fe-Mo-Co alloy electrode and its catalytic activity for HER

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Rare Metals 2007年第3期26卷 205-212页

作者： LUO Beiping REN Buye XU You ZHENG Yajie Department of Chemistry and Chemical engineering Hunan Institute of Science and Technology Yueyang 414000 China college of Metallurgical science and engineering Central South University Changsha 410083 China Research Institute of materials science South China University of Technology Guangzhou 510640 China

A new pretreatment method has been developed to improve the catalytic activity of the Ni-Fe-Mo-Co alloy electrode for hydrogen evolution reaction （HER）. The procedure involves pre-electrolyzing the Ni-Fe-Mo-Co alloy electrode in 30% KOH solution containing 10% potassium sodium tartrate at 70℃ for 2 h, until some of the Mo and Fe elements are leached out. The surface morphology of the Ni-Fe-Mo-Co alloy demonstrates a unique hive-like structure after the pre- treatment, which has the pore size in a nanometer range （about 50 nm）, a very large real surface area, and good stability. The results of the electrochemical studies show that compared to other similar electrode materials and the treated Ni-Fe-Mo-Co electrode by leaching method, the pre-treated Ni-Fe-Mo-Co electrode has a much lower overpotential and much higher exchange current density for HER. In addition, a long-term continuous electrolysis test with a current interruption shows that the Ni-Fe-Mo-Co alloy has excellent catalytic stability.

关键词： catalytic activity surface treatment Ni-Fe-Mo-Co alloy hydrogen evolution electrodeposition

EFFECTS OF TRACE Zr ON FATIGUE CRACK GROWTH RATE OF HIGH DAMPING Zn-Al ALLOY

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中国有色金属学会会刊：英文版 1996年第3期6卷 92-95页

作者： Zhou Shanchu Luo Binghui (Department of materials science and engineering,Central South university of Technology, changsha 410083) CENT S UNIV TECHNOL DEPT MAT SCI & ENGNCHANGSHA 410083PEOPLES R CHINA

ＥＦＦＥＣＴＳＯＦＴＲＡＣＥＺｒＯＮＦＡＴＩＧＵＥＣＲＡＣＫＧＲＯＷＴＨＲＡＴＥＯＦＨＩＧＨＤＡＭＰＩＮＧＺｎ－ＡｌＡＬＬＯＹ￥ＺｈｏｕＳｈａｎｃｈｕ；ＬｕｏＢｉｎｇｈｕｉ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓ... 详细信息

ＥＦＦＥＣＴＳＯＦＴＲＡＣＥＺｒＯＮＦＡＴＩＧＵＥＣＲＡＣＫＧＲＯＷＴＨＲＡＴＥＯＦＨＩＧＨＤＡＭＰＩＮＧＺｎ－ＡｌＡＬＬＯＹ￥ＺｈｏｕＳｈａｎｃｈｕ；ＬｕｏＢｉｎｇｈｕｉ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅ...

关键词： Zr Zn-Al alloy fatigue crack growth rate internal friction

Influence of nanometric CeO2 coating on high temperature oxidation of Cr

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Progress in Natural science:materials International 2007年第5期17卷 601-606页

作者： Jin Huiming , Zhang Linnan and Liu Xiaojun (materials Research Center, Department of Mechanical engineering, Yangzhou university, Yangzhou 225009, china college of materials science and engineering, North-East university, Shenyang 110014, china) [a]materials Research Center Department of Mechanical Engineering Yangzhou University Yangzhou China [b]college of materials science and engineering North-East University Shenyang China

Isothermal and cyclic oxidation behavior of chromium and its superficially applied nanometric CeO2 samples were studied at 900℃in air. Scanning electronic microscopy (SEM), transmission electronic microscopy (TEM) and high resolution electronic microscopy (HREM) were used to examine the morphology and micro-structure of oxide films. It was found that ceria addition greatly improved the anti-oxidation ability of Cr both in isothermal and cyclic oxidizing experiments. Acoustic emission (AE) technique was used in situ to monitor the cracking and spalling of oxide films, and AE signals were analyzed in time-domain and number-domain according to the related oxide fracture model. Laser Raman spectrometer was also used to study the stress status of oxide films formed on Cr with and without ceria. The main reason for the improvement in anti-oxidation of chromium was that ceria greatly reduced the growing speed and grain size of Cr2O3. This fine-grained Cr2O3 oxide film might have better high temperature plasticity and could relieve parts of compressive stress by means of creeping, and maintained the ridge character and relatively low internal stress level. Meanwhile, ceria application reduced the size and the number of interfacial defects, while remarkably enhanced the adhesive property of Cr2O3 oxide scale formed on Cr substrate.

关键词： oxidation stress CeO2 nanoparticle coating chromium.

ELECTRON DIFFRACTION PATTERNS ANALYSIS OF PRECIPITATES IN LD_(10) ALLOY

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中国有色金属学会会刊：英文版 1995年第3期5卷 119-123页

作者： Jin, Tounan Yin, Zhimin(Department of materials science and engineering,Central South university of Technology, changsha 410083) Central South Univ of Technology Changsha China

ＥＬＥＣＴＲＯＮＤＩＦＦＲＡＣＴＩＯＮＰＡＴＴＥＲＮＳＡＮＡＬＹＳＩＳＯＦＰＲＥＣＩＰＩＴＡＴＥＳＩＮＬＤ_（１０）ＡＬＬＯＹ￥Ｊｉｎ，Ｔｏｕｎａｎ；Ｙｉｎ，Ｚｈｉｍｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳ... 详细信息

ＥＬＥＣＴＲＯＮＤＩＦＦＲＡＣＴＩＯＮＰＡＴＴＥＲＮＳＡＮＡＬＹＳＩＳＯＦＰＲＥＣＩＰＩＴＡＴＥＳＩＮＬＤ_（１０）ＡＬＬＯＹ￥Ｊｉｎ，Ｔｏｕｎａｎ；Ｙｉｎ，Ｚｈｉｍｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒ?..

关键词： precipitate simulated diffraction pattern transformation matrix

Dynamic scheduling model of computing resource based on MAS cooperation mechanism

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science in china(Series F) 2009年第8期52卷 1302-1320页

作者： JIANG WeiJin1,2, ZHANG LianMei3 & WANG Pu4 1 School of Computer and Electronic engineering, hunan university of Commerce, changsha 410205, china 2 School of Information engineering, Xiangtan university, Xiangtan 411000, china 3 Electrical engineering college, Wuhan university, Wuhan 430072, china 4 School of Commerce, Central South university, changsha 410083, china 1. School of Computer and Electronic engineering Hunan University of Commerce Changsha 410205 China 2. School of Information engineering Xiangtan University Xiangtan 411000 China 3. Electrical engineering college Wuhan University Wuhan 430072 China 4. School of Commerce Central South University Changsha 410083 China

Allocation of grid resources aims at improving resource utility and grid application performance. Currently, the algorithms proposed for this purpose do not fit well the autonomic, dynamic, distributive and heterogeneous features of the grid environment. According to MAS （multi-agent system） cooperation mechanism and market bidding game rules, a model of allocating allocation of grid resources based on market economy is introduced to reveal the relationship between supply and demand. This model can make good use of the studying and negotiating ability of consumers＇ agent and takes full consideration of the consumer＇s behavior, thus rendering the application and allocation of resource of the consumers rational and valid. In the meantime, the utility function of consumer is given; the existence and the uniqueness of Nash equilibrium point in the resource allocation game and the Nash equilibrium solution are discussed. A dynamic game algorithm of allocating grid resources is designed. Experimental results demonstrate that this algorithm diminishes effectively the unnecessary latency, improves significantly the smoothness of response time, the ratio of throughput and resource utility, thus rendering the supply and demand of the whole grid resource reasonable and the overall grid load balanceable.

关键词： multi-agent system (MAS) resource scheduling model evolutionary game cooperation mechanism utility function

TiC－PHASE　DIFFUSION　LAYER　FORMATION　IN　TITANIUM　CLAD　STEEL　COMPOSITE　HAVING　AN　INTERMEDIATE　LAYER　OF　α－Fe

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中国有色金属学会会刊：英文版 1996年第2期6卷 76-80页

作者： Xia Changqing Jin Zhanpeng(Department of materials science and engineering,Central South university of Technology, changsha 410083) CENT S UNIV TECHNOL DEPT MAT SCI & ENGNCHANGSHA 410083PEOPLES R CHINA

ＴｉＣ－ＰＨＡＳＥＤＩＦＦＵＳＩＯＮＬＡＹＥＲＦＯＲＭＡＴＩＯＮＩＮＴＩＴＡＮＩＵＭＣＬＡＤＳＴＥＥＬＣＯＭＰＯＳＩＴＥＨＡＶＩＮＧＡＮＩＮＴＥＲＭＥＤＩＡＴＥＬＡＹＥＲＯＦα－ＦｅＸｉａＣｈａｎｇｑｉｎｇ；ＪｉｎＺ... 详细信息

ＴｉＣ－ＰＨＡＳＥＤＩＦＦＵＳＩＯＮＬＡＹＥＲＦＯＲＭＡＴＩＯＮＩＮＴＩＴＡＮＩＵＭＣＬＡＤＳＴＥＥＬＣＯＭＰＯＳＩＴＥＨＡＶＩＮＧＡＮＩＮＴＥＲＭＥＤＩＡＴＥＬＡＹＥＲＯＦα－ＦｅＸｉａＣｈａｎｇｑｉｎｇ；ＪｉｎＺｈａｎｐｅｎｇ（Ｄｅｐａｒｔｍｅｎ...

关键词： TiC-phase carbon activity stationary diffusion

EVOLUTION　OF　MICROSTRUCTURE　IN　OXIDATIVE　GROWTH　OF　Al_2O_3／Al　ALLOY　COMPOSITES

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中国有色金属学会会刊：英文版 1996年第3期6卷 122-126页

ＥＶＯＬＵＴＩＯＮＯＦＭＩＣＲＯＳＴＲＵＣＴＵＲＥＩＮＯＸＩＤＡＴＩＶＥＧＲＯＷＴＨＯＦＡｌ_２Ｏ_３／ＡｌＡＬＬＯＹＣＯＭＰＯＳＩＴＥＳ￥ＸｉａＣｈａｎｇｑｉｎｇ；ＪｉｎＺｈａｎｐｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａ... 详细信息

ＥＶＯＬＵＴＩＯＮＯＦＭＩＣＲＯＳＴＲＵＣＴＵＲＥＩＮＯＸＩＤＡＴＩＶＥＧＲＯＷＴＨＯＦＡｌ_２Ｏ_３／ＡｌＡＬＬＯＹＣＯＭＰＯＳＩＴＥＳ￥ＸｉａＣｈａｎｇｑｉｎｇ；ＪｉｎＺｈａｎｐｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄ...

关键词： oxide layer Al2O3/Al alloy composites oxygen activity