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Acta Mathematica Sinica,English Series 1999年第1期15卷 1-10页

作者： Weiping lidepartment of Mathematics,Oklahoma State University,Stillwater,Oklahoma 74078-0613,USA Department of Mathematics Oklahoma State University Stillwater USA

Using a kind of Mayer-Vietoris principle for the symplectic Floer homology of knots,we compute the symplectic Floer homology of the square knot and granny knots.

关键词： Knot Knot Cobordism Maslov Index Floer Homology

NOVEL METHOD OF REALIZING THE OPTIMAL TRANSMISSION OF THE CRANK-AND-ROCKERMECHANISM DESIGN

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Chinese Journal of Mechanical Engineering 2003年第1期16卷 31-33页

作者： Fang Shijie Li lidepartment of Mechanical Engineering,yantai University,yantai 264005, China Department of Mechanical Engineering Yantai University Yantai 264005

A novel method of realizing the optimal transmission of the crank-and-rockermechanism is presented. The optimal combination design is made by finding the related optimaltransmission parameters. The diagram of the optimal transmission is drawn. In the diagram, therelation among mini-mum transmission angle, the coefficient of travel speed variation, theoscillating angle of the rocker and the length of the bars is shown, concisely, conveniently anddirectly. The method possesses the main characteristic. That it is to achieve the optimaltransmission parameters under the transmission angle by directly choosing in the diagram, accordingto the given requirements. The characteristics of the mechanical transmission can be improved togain the optimal transmission effect by the method. Especially, the method is simple and convenientin practical use.

关键词： Crank-and-rocker mechanism Optimal transmission angle Coefficient oftravel speed variation

Synthesis of TiN/AlON composite ceramics

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Journal of University of Science and Technology Beijing 2003年第1期10卷 49-53页

作者： Xidong Wang, Lichun Gao, Guobao Li, and Wenchao lidepartment of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China Dept. of Phys. Chem. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The synthesis process of TiN/AlON composite ceramics was studied, the thermodynamics, mechanical properties and micro-structures of TiN/AlON have also been investigated. The TiN/AlON composite ceramics has been synthesized by both hot-pressing and pressureless sintering. The characterizations of the material synthesized were analyzed with XRD (X-ray diffraction) and TEM (transmission electronic microscope). The density and toughness strength of TiN/AlON are 3.57g/cm3 and 4.74MPa.m1/2, respectively. The bending strength was measured at both room temperature and high temperatures and the results are 399 MPa (room temperature), 406 MPa (1 073 K), 417 MPa (1 273 K) and 323 MPa (1 573 K). Pattern Recognition (PR) and Artificial Neural Network (ANN) were used to optimize the parameters and to predict the expected values. A proper parameter for pressureless sintering of TiN/AlON has been obtained and testified, the parameters are temperature (1 978 K), AlN / (AlN + Al2O3) ratio (0.22), MgO (4.7%) and TiO2 (7.2%).

关键词： synthesis TiN AlON composite ceramics

Effect of Zinc on Bone Metabolism in Fetal Mouse Limb Culture

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Biomedical and Environmental Sciences 2002年第4期15卷 323-329页

作者： LI YUN AND YU ZENG-lidepartment of Nutrition and Food Hygiene, Huaxi School of Public Health, Sichuan University, Chengdu 610041. China Department of Nutrition and Food Hygiene Huaxi School of Public Health Sichuan University Chengdu 610041 China

Objective To determine the effects of zine-deficiency and zine-excess on hone metabolism. Methods We developed the culture model of fetal mouse limbs (16th day) cultivated in self-made rotator with continuing flow of mixed gas for six days in vitro. The cultured limbs were examined by the techniques of 45Ca tracer and X-roentgenography. Results The right limbs cultivated had longer bone length, higher bone density than the left limbs uncultivated from the same embryo; and histologically, the right limbs had active bone cell differentiation, proliferation, increased bone trabecula. clearly calcified cartilage matrix, and osteogenic tissue. Compared with the control group, the zinc-deficient group and zine-excess (Zn2+ l20) μmol/L) group contained less osteocalcin (BGP) and 45Ca content, and lower AKP activity; whereas zine-normal (Zn2+ 45 μmol/L and Zn2+ 70 μmol/L) groups contained more BGP and 45Ca contents, and higher AKP (alkaline phosphatase) activity. Conclusion Both zine-deficiency and zine-excess can alter bone growth and normal metabolism. The results indicate that the culture model of fetal mouse limbs (16th day) in vitro can be used as a research model of bone growth and development.

关键词： Zinc excess Zinc deficiency Bone metabolism Organic culture

REVISED k-ε TURBULENCE MODEL IN ELECTROMAGNETIC CONTINUOUS CASTING OF MELT

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 395-400页

作者： H.F. Huo and B.K. lidepartment of Thermal Engineering, School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China. Dept. of Thermal Eng. Sch. of Mat. and Metall. Northeastern Univ. Shenyang 110004 China

The research is motivated by the ongoing the electromagnetic continuous casting of molten metal. The revised k-ε model considering the effect of magnetic field application was derived. The specific model equations for the electromagnetic braking were used to calculate the velocity distribution in the continuous casting mold of steel. The results show that the revised k-ε model considering the effect of magnetic field application tends to suppress the production of turbulence and difference between the conventional and revised k-e model is small.

关键词： revised k-ε turbulence model electromagnetic continuous casting magnetic field

Finite Groups Acting 2-Transitively on Their Sylow Subgroups

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Acta Mathematica Sinica,English Series 1999年第1期15卷 131-144页

作者： Caiheng lidepartment of Mathematics,the University of Western Australia,Nedlands,WA,6907,AustraliaJie WangDepartment of Mathematics,Peking University,Beijing 100871,P.R.China Department of Mathematics the University of Western Australia Nedlands Australia Department of Mathematics Peking University Beijing P. R. China

In this paper we have completely determined:(1)all almost simple groups which act 2-transitively on one of their sets of Sylow p-subgroups.(2)all non-abelian simple groups T whose automorphism group acts 2-transitively on one of the sets of Sylow p-subgroups of T.(3)all finite groups which are 2-transitive on all their sets of Sylow subgroups.

关键词： Finite group Sylow subgroup 2-transitive action

Computer simulation of strain-induced morphological transformation of coherent precipitates

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Journal of University of Science and Technology Beijing 2003年第4期10卷 55-60页

作者： Yuhong Zhao, Zheng Chen, and Xiaoling lidepartment of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China Northwestern Polytech Univ Dept Mat Sci & Engn Xian 710072 Peoples R China

The coherent elastic strain-induced morphological transformation of a binarycubic model alloy was simulated with different strain energy parameters. The microscopic diffusionequation was combined with the theory of microscopic elasticity. The results show that when thestrain energy is neglected, the randomly distributed equiaxed particles are obtained with isotropiccharacteristic. It is coarsening that follows the Ostwald ripening mechanism: smaller particlesdwindle and larger particles grow; when the elastic strain is considered, plate precipitates tend toalign along the elastically soft directions with anisotropic characteristic. The particlesgrow in the soft directions and coarsen further; particles dwindle in out of the soft *** the coarsening of the particles localized in the same row or column follows the rule: smallerparticles shrink and larger ones grow.

关键词： elastic strain energy coherent precipitate model alloy and computersimulation

STRUCTURAL AND ELECTRONIC EFFECTS OF TiO2 IN CuO-ZnO/Al2lO3-TiO2 CATALYST

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Journal of Energy Chemistry 1994年第2期 173-180页

作者： LIU Jia yanG Xi-Yao PANG lidepartment of Chemistry , Peking University Beijing 100871

The modification effects of TiOtowards Cu or CuO in supportedCuO-ZnO/AlO-TiOcatalyst were studied by XPS,TPD and test *** showed that TiOadditive improved the dispersity of CuO or Cu in *** showed that the reduction temperature（Tr）of CuO in CuO-ZnO/AlO-TiOincreased with the content of *** showed that the Eb valueof Cu in TiOcontaining catalyst（Eb=993.7 eV） was larger than that inTiOfree catalyst（Eb=932.9 eV）.These indicate that TiOdisplayed elec-tronic effect on *** structural effect improving the dispersity of Cuand electronic effect weakening the bond strength of Cu-S in catalyst caused theS-resistance of CuO-ZnO /AlO-TiOcatalyst greatly improved.

关键词： CuO AI TiO ZnO Al

A Coalitional Power Value for Set Games

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 417-424页

作者： Hao Sun, Sheng-gui Zhang, Xue-liang lidepartment of Applied Mathematics, Northwestern Polytechnical University, Xi’an 710072. China Department of Applied Mathematics Northwestern Polytechnical University Xi’an 710072 China

We propose the concept of a coalitional power value for set games, and present its axiomatic characterization of global effciency, equal treatment property and coalitional power monotonicity. The coalitional power val... 详细信息

关键词： Set games value axiomatic characterization