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Journal of university of Science and Technology beijing 2001年第2期8卷 126-128页

作者： Yanjun li, Weimin Mao, Zisheng Zhen, Xueyou Zhong (Material Science and Engineering School, university of Science and Technology {2., beijing 100083, China) Univ Sci & Technol beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China

The microstructural evolution and apparent viscosity of hypereutectic Al-2.%Si alloy during semi-solid state shearing were studied with a Searte type viscometer. When the alloy melt was continuously stirred from 72. degreesC to eutectic temperature, the primary Si crystals were gradually changed from elongated platelets to near-spherical shapes. It was found that some nondendritic a-phase formed when the melt was stirred below 585 degreesC. The experiment showed that the semi-solid stirring had strong effect on inhibiting the anisotropic growth of Si crystals during solidification. The apparent viscosity of the alloy melt increased slowly with the decreasing of temperature before the formation of nondendritic alpha -phase, which caused the dramatic increase of apparent viscosity.

关键词： hypereutectic Al-Si alloy solidification structures apparent viscosity

Cathodic electrolysis method of depositing cerium conversion films on industrial pure aluminum

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Rare Metals 2002年第2期21卷 95-100页

作者： ZHANG Wei, li Jiuqing, WU Yinshun, SHEN Defeng, and HE JianpingDepartment of Surface Science & Corrosion Engineering, university of Science and Technology {2., beijing 100083, China Department of Surface Science & Corrosion Engineering University of Science and Technology Beijing 北京 100083

Two two-step techniques, called TS2.TS7 and TS3/TS7, respectively,have been developed to form cerium conversion films on the surface ofindustrial pure aluminum. The tested material was cathodicallyelectrolyzed in the al- kaline solution containing cerium salt, anduniform films containing cerium were obtained after the two-steptreatment. It is found that the films obtained by TS2.TS7 and TS3/TS7techniques are about 4.0 and 3.0 um in thickness, respectiv- Ely. Thematerial has better corrosion resistance in the chloride solutionafter the two-step electrolysis treatent compar- Ed with the one-steptreated and naked specimens.

关键词： aluminum alloy rare earth conversion film cathodic electrochemicaldeposition

Reduction of Coercivity of Fe-N Soft Magnetic Film by Heat Treatment

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Journal of Materials Science & Technology 2003年第5期19卷 491-494页

作者： Dan li, Yousong GU, Xiangrong CHANG, Fushen li, lijie QIAO and Zhongzhuo TIANDepartment of Materials Physics, university of Science & Technology beijing, beijing 100083, China Department of Materials Physics University of Science and Technology Beijing Beijing 100083 China

2.0 nm thick Fe-N magnetic thin films were deposited on glass substrates by RF sputtering. The as-deposited films have high saturation magnetization but their coercivity is also higher than what is needed Therefore it is very important to reduce coercivity. The samples were vacuum annealed at 2.0℃ under 12.00 A/m magnetic field. When the N content was in the range of 5-7 at. pct, the thin films consisted of α' +α' after heat treatment and had excellent soft magnetic properties of 4πMs=2.4 T, HC 2.m, and Hc increased as thickness increased. In order to reduce the Hc, the sputtering power was raised from 2.0 W to 1000 W to reduce the grain size. 2.m Fe-N thin films were vacuum annealed under the same condition, when the N content was in the range of 5.9-8.5 at. pct, the thin films kept its excellent magnetic properties of 4πMs=2.2.T, HC <80 A/m. The properties of the films meet the need of a recording head material used in the dual-element GMR/inductive heads.

关键词： Fe-N Soft magnetic film Coercivity

Characterization and Comparison of Conducting Polyaniline Synthesized by Three Different Pathways

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Journal of Wuhan university of Technology(Materials Science) 2011年第6期26卷 1068-1072页

作者：董超芳 Corrosion & Protection Center University of Science and Technology Beijing Key Laboratory for Corrosion and Protection of Ministry of Education

The conducting polyaniline （PANI） prepared by three chemical oxidative polymerization pathways including microemulsion, emulsion and aqueous solution methods were studied and compared. Their structures, morphologies and properties were characterized using FT-IR, XRD, TEM and TGA. PANI particles formed in aqueous solution have a smallest size and doping HCl enables to increase their conductivity. In contrast, PANI particles prepared by emulsion method have the highest thermal stability and conductivity and more ordered morphology. Rather different from these two methods, microemulsion approach allows forming nanocomposite PANI with tube-like nanostructure.

关键词： nano materials polymers polyaniline

Services Discovery for Distributed Network Measurement

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计算机工程 2002年第S1期28卷 28-32页

作者： li Wei, QIAN Depeili Yunchun, SHI Nayan(Dept. of Computer Science &Technology,{2. university of Aeronautics &Astronautics,{2. 100083,China) Dept. of Computer Science &Technology Beijing University of Aeronautics &AstronauticsBeijing 100083China

More and more distributed applications are deployed around interconnected network, which makes it necessary for network measurement services to address the scalability and robustness requirements. This paper discusses a service discovery forintegrated network measurement architecture (INMA), including finding the location of measurement agent, the path of the measurement and the network attributes of the end-to-end path or host. It also describes the functions of the major building blocks used to construct the measurement architecture.

关键词： Service discovery Network measurement Directory server

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： li Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. Department of Mathematics, beijing Normal {2., beijing 100875, China 2. Department of Mathematics, Neijiang Teacher's College, Neijiang 641112. China) beijing Normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators

Study on Microstructure and Property of H13 Die Steel with Nitrogen

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稀有金属材料与工程 2011年第S3期40卷 234-236页

作者： Chen Yulai, liu Biao, Zhao Peng, Tang Di, li Jingyuan {2. of Science and Technology beijing, beijing 100083,China Univ Sci & Technol Beijing 100083 Peoples R China

Composition segregation and microstructure nonuniform of H13 steel have been obviously improved though adding nitrogen element. The microstructure and property of H13 steel with nitrogen contents of 0.02.% and 0.085% are studied under various quenching and tempering states. Dual quenching that is quenching between 1000-1010 ℃ twice is employed in order to increase the tensile strength and hardness of coupons. The temperature and time are explored for improving the toughness under optimal quenching treatment. For extrusion die steel, the tensile strength can reach a satisfactory level and impact toughness are met the requirements of NADCA at the temperature.

关键词： H13 steel nitrogen chemical composition mechanical property

Synthesis and thermodynamic analysis of nano-La2.3

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Progress in Natural Science:Materials International 2007年第7期17卷 838-844页

作者： liu lili~(1,2. Tang Jie~2.li Yuxiang~1 Zhang Mei~(1**) Wang Xidong~(1,3) (1.Department of Physical Chemistry,university of Science and Technology beijing,beijing 100083,China 2.National Institute for Materials Science,Segen 1-2.1,Tsukuba 305-0047,Japan 3.College of Engineering,beijing university,beijing 100871,China) [a]Department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]National Institute Materials Science Tsukuba Jpan [c]College of Engineering Beijing University Beijing China

The thermodynamic parameters of La（NO3）3and La（OH）3are evaluated and the thermodynamics of nano-La2.3syn- thetic process is *** the base of thermodynamic analysis,La2.3nano-powders are prepared by the sol-gel method and the experi- ment scheme is designed by an orthogonal *** dry-gelatin is analyzed with differential thermal analysis/thermo-gravimetric analy- sis（TGA-DTA）and X-ray diffraction *** microstructure of nano-La2.3powders is observed by transmission dectron micro- *** synthetic parameters affecting the average grain size and dispersivity of nano-La2.3particles are experimentally examined and *** the results indicate that nano-La2.3particles well-dispersed are obtained and the average grain size is in the range of 2.—50 nm.

关键词： nano-La2.3 sol-gel thermodynamic analysis

Theoretical study on the reaction mechanism of (CH3)3CO(.) radical with NO

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Science China Chemistry 2004年第4期47卷 289-294页

作者： ZHAO Hongmei1,2. liU Kun1, SUN Chengke1 & li Zonghe1 1. Department of Chemistry, {2. Normal university, {2. 100875, China 2. Department of Chemistry, Beihua university, Jilin 132.13, China 1. Department of Chemistry Beijing Normal University 100875 Beijing China 2. Department of Chemistry Beihua University 132013 Jilin China

The reaction mechanism of (CH3)3CO? radical with NO is theoretically investigated at the B3LYP/6-31G* level. The results show that the reaction is multi-channel in the single state and triplet state. The potential energy surfaces of reaction paths in the single state are lower than that in the triple state. The balance reaction: (CH3)3CONO(CH3)3CO?+NO, whose potential energy surface is the lowest in all the reaction paths, makes the probability of measuring (CH3)3CO? radical increase. So NO may be considered as a stabilizing reagent for the (CH3)3CO? radical.

关键词： (CH3)3CO. radical DFT reaction mechanism NO

ZrO_2.and ZrO_2.Y_2._3 coatings deposited by double pulsed plasma arc

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Chinese Science Bulletin 2002年第3期47卷 252-254页

作者： YU Weiping, li Fan & MENG lin{2. university of Aeronautics and Astronautics, beijing 100083, China beijing university of Aeronautics and Astronautics Beijing China

A novel surface technique has been developed to produce ZrO2.and ZrO2.Y2.3 coatings on the surface of alloys by using double pulsed plasma arc to react with a so-lution film containing nano-oxide particles. These coatings exhibit smooth surface and excellent adhesion with substrate. The morphologies of the ceramic coatings and phases were analyzed. It was shown that the oxidation resistance of 18-8 stainless steel was markedly improved by applying ZrO2.and ZrO2.Y2.3 coatings.

关键词： double pulsed plasma arc ceramic coatings high temperature oxidation.