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Journal of materials science & Technology 2000年第5期16卷 543-545页

作者： Guohui ZHU, Weimin MAO+ and Yongning YU (department of Metal materials, university of science and Technology beijing, beijing 100083, china) department of Metal materials University of Science and Technology Beijing Beijing 100083 China

The orientation distribution of recrystallization grains formed during annealing, as well as their misorientation relationship to the deformation matrix in cold rolled FeCo alloy have been investigated. It was found that most of the recrystallization nuclei were located near the boundary area with rather random orientations, and their misorientation angles to the deformation matrix were generally very high. However a few nuclei were also observed inside the deformation grains, to which they had very similar orientations. Therefore the misorientation angles between the nuclei and the deformation matrix were generally very low. The orientation and the misorientation distributions of the nuclei have very strong influence on the recrystallization process which could result in a very weak recrystallization texture. The corresponding mechanism is discussed.

关键词： In Nucleation of Cold Rolled FeCo Alloy during Annealing and Its Influence on the Formation of Recrystallization Texture

An equality on Hochschild homology groups

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Chinese science Bulletin 1997年第8期42卷 624-627页

作者： ZHANG Pu and LIU Shaoxue1. department of Mathematics, university of science and Technology of china, Hefei 230026, china 2. department of Mathematics, beijing normal university, beijing 100875, china department of Mathematics University of Science and Technology of China Hefei China department of Mathematics Beijing Normal University Beijing China

LET A be finite-dimensional algebra over field k,and Ae the enveloping algebra of A,i.e.Ae=A kAop,where Aop is the opposite algebra of *** A-bimodule has a natural left Ae-module structure as follows:

关键词： finite-dimensional algebra Hochschild homology groups dimensions.

A Discussion on Evolution of Microstructures and Influence Factors during Continuous Rolling of Compact Strip Production

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Journal of materials science & Technology 2004年第3期20卷 274-278页

作者： Hongbo DONG Yonglin KANG Hao YU department of materials Processing and Controlling, university of science and Technology beijing, beijing 100083, china Dept. of Mat. Proc. and Control Univ. of Sci. and Technol. Beijing Beijing 100083 China

The evolution of microstructures and influence factors of ultrathin hot strips of low carbon steel produced by compactstrip production (CSP) techniques were investigated. The steel blocking samples of CSP six-passes were obtained,and microstructures at the different positions of workpiece for each pass were studied. At the same time, anexplicit finite element technique was used to reveal the continuous rolling process. By combining experiment resultswith simulation analysis, the effects of plastic strain, temperature, precipitation and interval time on evolution andrefinement of crystal grains have been investigated. The results are useful for the development of high strength hotstrips.

关键词： CSP Microstructure Strain Temperature Precipitation

Central limit theorem for the occupation time of catalyticsuper-Brownian motion

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Chinese science Bulletin 1998年第24期43卷 2035-2040页

作者： HONG Wenming department of Mathematics, beijing normal university, beijing 100875, china Corresponding address: Institute of Mathematics, Shantou university, Shantou 515063, china department of Mathematics Beijing Normal University Beijing China

The catalytic super_Brownian motion has been considered. If both the catalytic medium process Q and CSBM started with Lebesgue measure λ, the central limit theorem for occupation time of CSBM has been obtained in dim... 详细信息

关键词： branching rate functional Brownian collision local time catalytic super_Brownian motion occupation time central limit theorem.

Relationship among Parameters Evaluating Stress Corrosion Cracking

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Journal of materials science & Technology 2000年第5期16卷 504-508页

作者： Wuyang CHU+, Lijie QIAO and Yanbin WANG (department of materials Physics, university of science and Technology beijing, beijing 100083, china) department of materials Physics University of Science and Technology Beijing Beijing 100083 China

The threshold stress, σc, for sulfide stress corrosion cracking (SCC) of seven pipeline steels and five other steels, the critical stress, Sc, for seven pipeline steels and two drill rod steels with various strengths and the susceptibility to SCC, IRA or σf(SCC)/σf, for four pipeline steels, two drill rod steels and five other steels were measured. The results showed that there are no definite relationships among σc, Sc and IRA or σf(SCC)/σ*** threshold stress for hydrogen induced cracking (HlC) during charging with loading in the H2S04 solution, σc(H), decreased linearly with logarithm of the concentration of diffusible hydrogen c0, i.e., σc(H)=A-B Inco for four pipeline steels. σc(H) obtained with a special cathodic current ic, which was corresponding to the diffusible hydrogen concentration during immersing in the H2S solution, were consistent with /c for sulfide SCC for four pipeline steels. Therefore, σc for sulfide SCC can be measured using dynamically charging in the H2SO4 solution with the special cathodic current ic.

关键词： SCC Relationship among Parameters Evaluating Stress Corrosion Cracking HIC

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2 1 department of Physics, china university of Petroleum, Dongying 257061, china 2 department of Physics, beijing normal university, beijing 100875, china department of Physics China University of Petroleum Dongying China department of Physics Beijing Normal University Beijing China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Singularity detection of the rabbit electrocardiogram:An evolutionary spectral method

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Progress in Natural science:materials International 2009年第10期19卷 1317-1326页

作者： Xinyuan Liua,Dingwu He a,Liuqing Pei b,Suming Zhanga a School of Electronics engineering and Computer science,Peking university,beijing 100871,china b College of Information science and engineering,beijing normal university,beijing 100875,china School of Electronics engineering and Computer science Peking University Beijing 100871 China College of Information science and engineering Beijing Normal University Beijing 100875 China

The time-frequency characteristics of the spectral density of non-stationary signals(NSS) in the neighborhood of an instant time point can be determined using the evolutionary spectral *** experimental rabbit model involving ligation of the left anterior descending coronary artery to simulate the physiology of early phase myocardial ischemia(EPMI) has been previously ***,EPMI derived from left coronary artery stenosis is the main symptom of coronary heart diseases including acute myocardial ***,we propose a new algorithm for estimating the evolutionary spectral density functions,which is an effective approach to determine the instantaneous frequency spectra(IFS) of NSS under the uncertainty principle in the time-frequency *** localization singularity information in the data recorded from a living system could be detected by means of the ***(ECG) data recorded from experimental rabbits were analyzed with the new *** showed that the Q’s value of the evolutionary spectral quality number of the QRS-complex data was the characteristic parameter of ECG,and there was a matched connection between the time-frequency characteristics of QRS-complex data and the myocardial ischemia symptoms of the *** results provide valuable information regarding features of the EPMI for use in clinical diagnoses.

关键词： Non-stationary signals Electrocardiogram(ECG) Evolutionary spectrum Instantaneous frequency spectrum(IFS) Myocardial ischemia

Pointwise estimates for the maximal multilinear singular integral operators

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science china Mathematics 2005年第12期48卷 1696-1706页

作者： HU Guo’en, LI Dengfeng & LU Shanzhen department of Applied Mathematics, university of Information engineering, P. O. Box 1001 -747, Zhengzhou 450002, china College of Mathematical and Information sciences, Henan university, Kaifeng 475001, china department of Mathematics, beijing normal university, beijing 100875, china department of Applied Mathematics University of Information Engineering Zhengzhou 450002 China College of Mathematical and Information sciences Henan University Kaifeng 475001 China department of Mathematics Beijing Normal University Beijing 100875 China

Two pointwise estimates relating the maximal multilinear singular integral operators and some classical maximal operators are established. These pointwise estimates imply the rearrangement estimate and the BLO(Rn) est... 详细信息

关键词： multilinear singular integral,maximal operator,BMO (Rn),BLO (Rn).

Shrinkage Behaviour of Spheroidal Graphite Cast Iron in Green and Dry Sand Molds for the Benchmarking of Solidification Simulation

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Journal of materials science & Technology 2001年第6期17卷 610-614页

作者： Wenzhen LI and Baicheng LIU department of Mechanical engineering, Tsinghua university, beijing 100084, china Jiarong LI beijing Institute of Aeronautical materials, beijing 100095, china [Manuscri Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China

The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroids graphite cast iron castings were discussed. Finally, two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.

关键词： Shrinkage Behaviour of Spheroidal Graphite Cast Iron in Green and Dry Sand Molds for the Benchmarking of Solidification Simulation Graphite Simulation Cast

Proof of inseparable prime C~*-algebras A with RR(A)=0 being primitive C~*-algebras

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Chinese science Bulletin 1999年第8期44卷 688-690页

作者： ZHANG Lunchuan and MA Jipudepartment of Mathematics , beijing normal university , beijing 100875, china department of Mathematics , Nanjing university, Nanjing 210093, china department of Mathematics Beijing Normal University Beijing China department of Mathematics Nanjing University Nanjing China

First, that prime C~* -algebras with countable primitive ideals are all primitive C*-algebras is proved. Then the proof that prime C~* -algebras with property RR(A) = 0 are all primitive C~*-algebras is given.

关键词： prime C~*-algebras primitive C~*-algebras hereditary C~*-algebras open projection and close projection.