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Fuzzy Pattern Recognition in Atlas and Images of the Unevenness of Carbide in Tool Steel

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Journal of university of science and Technology {2. 2001年第3期8卷 234-236页

作者： Hui Zhang, Angui Li, Zhigang Zhang, Li Jiang Applied science school, {2. of science and Technology beijing, beijing 100083. china Univ Sci & Technol beijing App Sci Sch Beijing 100083 Peoples R China

Fuzzy pattern recognition has been employed to identify some atlas and images of the unevenness of carbide in tool steel. Three models have been constructed. These models were based on fuzzy mathematics theory, as well as fuzzy pattern recognition method. Distribution rule of the unevenness of eutectic carbide in ledeburite steel is proposed in these models respectively.

关键词： fuzzy mathematics fuzzy and pattern recognition characteristic specimen

Force Parameter Model of 3-Roll Mills for Continuous Cold Rolling Wires

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International Journal of Minerals,Metallurgy and materials 1999年第4期13卷 292-295页

作者： Baolong Zheng1 Li Sun2.Ruichen An2.Jin Wang1 Weichang Zhu1(l material science and Engineering {2., university of science and Technology beijing, beijing 100083. china2.Tangshan iron and Steel Co. Ltd., Tangshan 063000, china) material science and Engineering {2. University of Science and Technology Beijing Beijing 100083 China Tangshan Iron and Steel Co. Ltd. Tangshan 063000 China

Based on experimental data, the mathematical model of rolling force parameters of 3-roll mills was studied. The structure ofthe model was theoretically set up and the coefficients were determined by static analysis of the data. The torque in continuous rollingwas measured, and the characteristics and efficiency of 3-roll mills are investigated.

关键词： 3-roll mill force mathematical model cold rolling wire

Refinement of packet size in low carbon bainitic steel by special thermo-mechanical control process

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Journal of university of science and Technology {2. 2004年第3期11卷 221-224页

作者： Chengjia Shang Xuemin Wang Shanwu Yang Xinlai He materials science and Engineering {2., university of science and Technology beijing, beijing 100083. china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The packet size of bainitic steel can be refined by a specialrelaxation-precipitation-control phase transformation (RFC) technology. When processed by RPCprocess, the low carbon bainitic steel composes of two kinds of main intermediate transformationphases. One is ultra-fine lath-like bainitic ferrite and the lath is less than 1μm in width andabout 6 μm in length; the alignment of laths forms a refined packet, and the size of packets isabout 5-7 μm in length and about 3-4μm in width. The other is acicular structure. The morphologyand distribution of these acicular structures are influenced by relaxation process, the thin andshort acicular structures cut the prior austenite grain and refine the bainitic packet size. For theoptimum relaxation time, the packet size can be refined to the finest. The mechanical propertiesare influenced by relaxation time and the 800 MPa grade low carbon bainitic steel with excellenttoughness can be obtained by RPC process.

关键词： packet size refinement bainitic steel RPC process

A new theorem to synchronization of unified chaotic systems via adaptive control

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Journal of university of science and Technology {2. 2003年第6期10卷 72-75页

作者： Lequan Min and Jianyi JingApplied science school, {2. of science and Technology beijing, beijing 100083. china Univ Sci & Technol beijing Appl Sci Sch Beijing 100083 Peoples R China

Chaos synchronization has been applied in secure communication, chemicalreaction, biological systems, and information processing. A new theorem to synchronization ofunified chaotic systems via adaptive control is proposed. The constructive theorem provides thedesign scheme for adaptive controller such that a respond system can synchronize with respect to anuncertain drive system. One example for discontinuous chaotic system is proposed to illustrate theeffectiveness and feasibility.

关键词： uncertain chaotic system adaptive control synchronization Chua's circuit

Kinetics of Evaporation of Zn and Pb from Carbon-bearing Pellets Made of Dust Containing Zn-Pb-Fe Oxides

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International Journal of Minerals,Metallurgy and materials 2000年第3期14卷 178-183页

作者： Weiqing Chen, Dongyan Wang, Rongzhang Zhou, Zongcai Lin (Metallurgy school, university of {2. and Technology beijing, beijing 100083. china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

The influence of reduction temperature, size of coal powder and the carbon content on the evaporation rates of Zn and Pb in pellets made of ZnO-PbO-FeO bearing dust has been investigated between 1100-1300℃. The evaporation rate of Zn and Pb obtained from the experiments has been analyzed with kinetic models. The results show that the control step for evaporation of Zn is reduction reaction of ZnO by CO at the interface，and that the evaporation rate of Pb is controlled by the volatilization of reduction products, i.e. liquid lead. The overall apparent activation energies of Zn and Pb evaporation from the pellet are 79.42.J/mol and 88.74kJ/mol respectively.

关键词： Zn-Pb-bearing dust carbon-containing pellet evaporation kinetics

Magnetic properties and structure of very thin permalloy films

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Journal of university of science and Technology {2. 2004年第3期11卷 225-229页

作者： Guanghua Yu Haifeng Li Tao Yang Fengwu Zhu materials science and Engineering {2., university of science and Technology beijing, beijing 100083. china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

In order to study the magnetic properties and structure of very thinpermalloy films, Ni_(81)Fe_(19) films of 12.nm in thickness were prepared by different instrumentsat an ultrahigh base vacuum and a lower base vacuum. The anisotropic magnetoresistance coefficients(ΔR/R) of Ni_(81)Fe_(19) (12.nm) films reached 1.6 % and 0.6 %, and the coercivities were 12. and334 A/m, respectively. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were usedto study the structure and surface chemical state. The experimental results show that the filmsprepared at the ultrahigh base vacuum have a smoother surface, a bigger grain size and a denserstructure with fewer defects than those prepared at the lower base vacuum.

关键词： NiFe film anisotropic magnetoresistance (AMR) coercivity structure

Stability on Finite Time interval andTime-Dependent Bifurcation Analysis ofDuffing's Equations

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Communications in Nonlinear science and Numerical Simulation 1999年第4期4卷 268-271页

作者： Cuncai HUA Qishan LU(school of science, {2. university of Aeronautics and Astronautics, {2. 100083.china) school of science Beijing Univ. Aero. and Astronaut. Beijing 100083 China

IntroductionInPhysics,MechanicsandEngineering,ChemistryandLifescienceetc.,thereealstbfforcationproblemsm***etimepassingthrought... 详细信息

IntroductionInPhysics,MechanicsandEngineering,ChemistryandLifescienceetc.,thereealstbfforcationproblemsm***etimepassingthrought...

关键词： stability on finite time interval time-dependent bifurcation Duffing’s equa-tion

Numerical Modeling of NO Formation during Packed-bed Combustion of Coke Granules

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International Journal of Minerals,Metallurgy and materials 2000年第4期14卷 261-268页

作者： Chunbao Xu, Shengli Wu, Daqiang Cang (Metallurgy school, university of {2. and Technology beijing, beijing 100083. china Institute for Chemical Reaction {2., Tohoku university, Japan) Metallurgy school University of Science and Technology Beijing Beijing 100083 China Institute for Chemical Reaction science Tohoku University Japan

A comprehensive kinetic model of NO formation during coke combustion in packed-bed in presence of noncombustible particles was developed. The detailed homogeneous gas-phase chemistry (including 102.chemical reactions), heterogeneous gas-solid chemistry (including 11 reactions) of coke combustion and NO formation, and the heat and mass transfer were taken into account in the present model. The governing equations which are strongly coupled, non-linear and unsteady with 2. unknowns in total, were dispersed into differential equations with the finite differential method. Meanwhile, all the differential equations were numerically solved to give the time-histories and space-distributions oftemperatures of the bed and gas phase as well as the concentrations of all the gaseous species. By comparison, the experimental data were explained well by the calculated results. Based on the kinetic and mathematical model, the effects of O2.content of inlet gas, the initial chemical analysis of coke, bed-temperature and local reductive atmosphere (CO/O2. on NO formation during packed-bed coke combustion were numerically discussed. It was found that coke samples with a higher initial content of [N] and volatile matters, combusted under a suitable O2.containing atmosphere produced less NO emission. The reactions between CO and NO, catalyzed by high temperature surface of coke particles may be responsible for efficient reduction of NO.

关键词： kinetic model NO formation combustion packed-bed coke Metallurgy

Electrochemical Study of Hypophosphite

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International Journal of Minerals,Metallurgy and materials 1998年第1期12卷 23-25页

作者： Yuguo Yang Dongbai Sun Dongbai Sun Dejun Yang (materials science and Engineering {2., university of science and Technology beijing, beijing 100083. china) materials science and Engineering {2. University of Science and Technology Beijing Beijing 100083 China

Electrochemical behavior of hypophosphite was studied with cyclic voltammogram in acidic solution(pH = 4.6) at 80℃. Two anodic peaks were observed on gold electrode at - 0.44V and - 0.59 V (SCE),respectively, and no corresponding cathodic peaks were obtained. The one at - 0.44 V wits ascribed to the oxidation oftautomeric form of hypophosphite, the other at - 0.59 V was due to the oxidation of absorbed form of hypophosphite. The two oxidation reactions were believed to be the electron source of nickel ion reduction in electrolessnickel processes.

关键词： cyclic voltammogram electroless nickel plating gold electrode hypophosphite