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Chinese Journal of Biomedical Engineering 2000年第3期 135-140页

作者： ZHANG Zuo sheng 1,PENG Hu 1,WEI Yong mei 2[WT4”BZ] 1.Institute of Biomedical Engineering of USTC,Hefei 230026,China 2.Physics Department of Fuyang Teachers College[WT5hz]

The fractal dimension property of 40hz event related potentials(ERPS) is studied for tests of Chinese word short term memory recognition, mental arithmetic calculation and short term memory capacity. By comparison it is found that there is a remarkable difference in the fractal dimensions of 40hz ERPS for different cognitive tasks. Meanwhile, for the identical cognitive process, there is a distinct hemispheric difference in fractal dimension property of 40hz ERPS, which indicates that there exists a noticeable difference in the property of brain dynamical between the two hemispheres under different cognitive tasks.

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A ESTIMATE OF THE RATE OF ENTROPY DISSIPATION OF HIGH RESOLUTION MUSCL TYPE GODUNOV SCHEMES

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Journal of Computational Mathematics 1999年第4期17卷 369-378页

作者： Tang, hz Zhao, N Chinese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Nanjing Univ Aeronaut & Astronaut Dept Aerodynam Nanjing 210016 Peoples R China

In this paper, following the paper [7], we analysis the 'sharp' estimate of the rate of entropy dissipation of the fully discrete MUSCL type Godunov schemes by the general compact theory introduced by Coquel-LeFloch [1, 2], and find: because of small viscosity of the above schemes, in the vincity of shock wave, the estimate of the above schemes is more easily obtained, but for rarefaction wave, we must impose a 'sharp' condition on limiter function in order to keep its entropy dissipation and its convergence.

关键词： hyperbolic conservation laws MUSCL type Godunov schemes entropy dissipation shock wave rarefaction wave

Studies on the reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanates and the synthesis of corresponding derivatives

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Chinese Journal of Chemistry 1996年第5期14卷 467-471页

作者： Zhao, GF Yang, hz NANKAI UNIV NATL KEY LAB ELEMENTOOGAN CHEMINST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

The reaction of 3-substituted-4-hydroxy-2H-1,2-benzothiazine 1,1-dioxides with aryl isocyanate under different equivalents of strong base NaH was studied. Seventeen of new derivatives were obtained whose structures we... 详细信息

关键词： benzothiazine dioxides reaction aryl isocyanate synthesis

Oxidative Rearrangement via Oxycerication with Ce(IV) Salt

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Chinese Chemical Letters 2000年第10期11卷 849-850页

作者： Wang, B Ma, hz Univ Northwest Dept Chem Xian 710068 Peoples R China

A mild and reliable procedure for the preparation of alpha-arylpropanoic acids from arylpropanone by Ce(IV) salt oxidative rearrangement is discribed.

关键词： oxidative rearrangement a-arylpropanoic acids Ce(IV) salt

Stepwise Oxidation of Ketene Dithioacetal

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Chinese Chemical Letters 2001年第10期12卷 865-868页

作者： Chen, K Yang, hz Nankai Univ Inst Elementoorgan Chem State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China

Stepwise oxidation of ketene dithioacetal is found and the different oxidation products changed with the amount of oxidant, temperature and reaction time.

关键词： oxidation reaction ketene dithioacetal hydrogen peroxide

Reliability Analysis for Offshore Platform Structural Systems

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China Ocean Engineering 1997年第1期12卷 1-10页

作者： Deng, hz Sun, Q NORTHWESTERN POLYTECH UNIV DEPT AIRCRAFT ENGNXIAN 710072PEOPLES R CHINA

A system reliability estimation method for spatial jacket platforms is developed in this paper. The jacket platform is modeled into three-dimensional assembly of spatial beam and plate elements in Finite Element Method (FEM). The limit failure states correspond to collapse of a series of structural members which are identified by engineering design criteria. In this paper the following aspects are taken into account: the punching shear and buckling failures in member failure modes for the tubular joints and tubular columns respectively; incremental loading approach for establishment of the safety margin equations of system failure; the algorithm of enumerating significant failure modes for the structural systems and other concepts, such as the false failure mode and the virtual limit state. The final work is devoted to the reliability analysis for a practical jacket platform presently put into operation on the Bohai Sea. The computed results shows that method suggested in this paper is feasible and effective for the evaluation of the system reliability of offshore platforms.

关键词： offshore structures system reliability analysis spatial jacket platform

ROLLING DEFORMATION LAW OF ALUMINIUM ALLOY CLAD SHEET

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中国有色金属学会会刊：英文版 1999年第2期9卷 77-81页

作者： Zhou, hz Wang, LY Huang, GJ SW Aluminium Fabricat Plant Chongqing 401326 Peoples R China Chongqing Univ Dept Met & Mat Engn Chongqing 400044 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＡｌＳｉ／ＡｌＭｎｔｒｉｌａｙｅｒｂｒａｚｅｄｃｌａｄａｌｕｍｉｎｉｕｍｓｈｅｅｔｉｓｔｈｅｍａｉｎｍａｔｅｒｉａｌｆｏｒｍａｋｉｎｇｅｖａｐｏｒａｔｏｒａｎｄｃｏｏｌｅｒｉｎｔｈ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＡｌＳｉ／ＡｌＭｎｔｒｉｌａｙｅｒｂｒａｚｅｄｃｌａｄａｌｕｍｉｎｉｕｍｓｈｅｅｔｉｓｔｈｅｍａｉｎｍａｔｅｒｉａｌｆｏｒｍａｋｉｎｇｅｖａｐｏｒａｔｏｒａｎｄｃｏｏｌｅｒｉｎｔｈｅａｉｒｃｏｎｄｉｔｉｏｎｅｒｏｆ...

关键词： aluminium alloyclad sheetrolling deformationdeformation lawcan be divided into 3 stages: free (slip or nonrestraining) deformation stage partial restraining (partial clad) deformation stage full restraining (full clad) deformation stage.

Sub-high Rate Directional Solidification

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Journal of Materials Science & Technology 1998年第1期14卷 9-14页

作者： Fu, hz Geng, XG Li, JG Zhang, J Northwestern Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China

The main features of morphology evolution of crystal growth during near rapid directional solidification were reviewed and the concept of effective constitutional supercooling was proposed. On the basis of interface stability theory combined with experiments, the behaviour of transition from dendrites to fine cells was quantitatively described, and the transition from cells to plane front of absolute stability was also examined.

关键词： Rapid solidification

Structure Based Library Approach to Photosynthesis Inhibitors:The Solid Phase Synthesis of Hydro-Uracils and Thiouracils

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Chinese Chemical Letters 1998年第2期9卷 139-142页

作者： Yu, AM Yang, hz Zhang, ZP Nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China Nankai Univ State Key Lab Funct Polymer Mat Adsorpt & Separat Tianjin 300071 Peoples R China

A general method for the solid phase synthesis of hydro-uracils and thiouracils is described. Resino ester 2 reacts with various primary amines to give secondary amines 3, which are converted to the resino ureas (thioureas) 4 by treatment with isocyanates (isothiocyanates). Preparation of the hydro-uracils and thiouracils 5 is achieved by acidic cyclization-cleavage from the resin. The synthesis is designed to be amenable for structure based library approach to photosystem II D1 protein inhibitors.

关键词： solid phase synthesis hydro-uracils and thiouracils photosynthesis inhibitors

The　Structure　of　Sophoridine　N－oxide　from　Inner　Mongolian　Sophora　Alopecuroides　L

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Chinese Chemical Letters 1996年第11期7卷 1013-1015页

作者： Zhang, W Mo, RG Xu, hz INNER MONGOLIA UNIV DEPT CHEMHOHHOT 010021PEOPLES R CHINA

Sophoridine N -oxide (A) was isolated from the seeds of Inner MongolianSophora alopecuroides L. Its structure was characteraized. Deoxygenation of A gave sophoridine whereas N-oxidation of sophoridine gave two N-oxide... 详细信息

关键词： Inner oxide Mongolian Sophoridine Structure Alopecuroides