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Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth Sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1.2.& LU Yang1.3 1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, {1. 2. Graduate school of the Chinese Academy of Sciences, Beijing 1.0039, {1. 3. Unite Center for Astro-geodymics Research, Chinese Academy of Sciences, shanghai 2.0030, {1. 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. Graduate {1. of the Chinese Academy of Sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01. derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01. model and the global MSSH. The spectral features of the QSST esti-mated by GGM01. and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01. fast Fourier transform, spectral analysis

Simulation of Thermodynamics and Kinetics for KR Desulphurization

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Journal of Iron and Steel Research International 2011年第S2期18卷 98-106页

作者： XU An-jun1. ZHANG Mao-lin2. ZHANG Hui-ning1. LI An-dong3 (1. {1. of Metallurgical and Ecological engineering, University of Science and Technology Beijing, Beijing 1.0083,{2. 2. Steel-Making and Continuous Casting engineering Institute, Capital engineering and Research Incorporation Limited, Beijing 1.01.6,{2. 3. Stainless Steel Company, Baosteel Group, shanghai 2.1.00,{2.) Univ Sci & Technol Beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China Capital Engn & Res Inc Ltd Steel Making & Continuous Casting Engn Inst Beijing 100176 Peoples R China Stainless Steel Co Baosteel Grp Shanghai 201900 Peoples R China

This paper seeks to optimize parameters, reduce the cost of desulphurization and the consumption of operation about KR pretreatment of hot metal at the Stainless Steel Company, Baosteel Group. Based on the theoretical analysis of physical chemistry in metallurgy, simulation experiments of the KR desulphurization of hot metal were conducted in a laboratory and the composition of the desulphurization was optimized, by means of chemical analysis, DSC, SEM and EDS. The water modeling displays the fluid flow characteristics of KR desulphurization. Combination of the techniques and production at the Stainless Steel Company, Baosteel Group, the optimized parameters of the process are put forward.

关键词： desulphurization of hot metal KR, desulphurization thermodynamics water model

Synthesis and Characteristics of an Aspartame Analogue,L-Asparaginyl L-3-Phenyllactic Acid Methyl Ester

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 385-389页

作者： Hu TAO1. Da-Fu CUI1. and You-Shang ZHANG1.2. 1.nstitute of Biochemistry and Cell Biology, {1. Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate school of the Chinese Academy of Sciences, {1. 2.0031. china Institute of Protein Research, tongji University, {1. 2.0031. china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China Institute of Protein Research Tongji UniversityShanghai 200031 China

An aspartame analogue, L-asparaginyl L-3-phenyllactic acid methyl ester was synthesized with aspartic acid replaced by asparagine and peptide bond replaced by ester bond. The aspartic acid of aspartame could be replaced by asparagine as reported in the literature. In this analogue, the hydrogen of amide group could still form a hydrogen bond with the oxygen of ester bond and the ester bond was isosteric with peptide bond. However, the product was not sweet, showing that the peptide bond could not be replaced by ester bond. The peptide C-N bond behaves as a double bond that is not free to rotate and the C, O, N and H atoms are in the same plane. The replacement of peptide bond by ester bond destroyed the unique conformation of peptide bond, resulting in the loss of sweet taste.

关键词： artificial sweetener aspartame derivative peptide bond

Global optimization of tool path for five-axis flank milling with a cylindrical cutter

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Science china(Technological Sciences) 2009年第8期52卷 2449-2459页

作者： DING Han1.& ZHU LiMin2.1.State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, {1. 2.school of Mechanical {2., shanghai Jiao Tong University, shanghai 2.02.0, {1. State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China school of Mechanical {1. Shanghai Jiao Tong University Shanghai 200240 China

In this paper, optimum positioning of cylindrical cutter for five-axis flank milling of non-developable ruled surface is addressed from the perspective of surface approximation. Based on the developed interchangeability principle, global optimization of the five-axis tool path is modeled as approximation of the tool envelope surface to the data points on the design surface following the minimum zone criterion recommended by ANSI and ISO standards for tolerance evaluation. By using the signed point-to-surface distance function, tool path plannings for semi-finish and finish millings are formulated as two constrained optimization problems in a unified framework. Based on the second order Taylor approximation of the distance function, a sequential approximation algorithm along with a hierarchical algorithmic structure is developed for the optimization. Numerical examples are presented to confirm the validity of the proposed approach.

关键词： five-axis flank milling tool path optimization tool axis trajectory surface surface approximation distance function minimax optimization

Multi-channel radar array design method and algorithm

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Science china(Information Sciences) 2010年第7期53卷 1470-1480页

作者： SU Yi1., ZHU YuTao1. YU WenXian2. XU HongBo1.& LEI WenTai1.1.1. of Electronic Science and engineering, National University of Defense Technology, Changsha 41.073, {2. 2.0} of Electric, Information and Electrical engineering, shanghai Jiao Tong University, shanghai 2.02.0, {2. 1. school of Electronic Science and {1. National University of Defense Technology Changsha 410073 China2. School of Electric Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China

The array design of radar antenna is no more a new problem at all. Nevertheless, the array design of multi-channel radar, especially that of MIMO (multiple-input multiple-output) radar, is a new problem. The performance of space diversion and spatial sampling of target scattering are dependent on the array design of MIMO radar, and consequently, which in turn will determine the performances of target parameter estimation, DOA, and imaging. In this paper, commencing with target scattering model, T/R signal model of MIMO radar, and spatial sampling ability for this system are analyzed. Conceptually, under the far field condition, spatial convolution principle determines the array design theory. Based on this idea, array design method and also algorithm are proposed in this paper.

关键词： MIMO-radar antenna arrays DOA estimation spatial sampling imaging algorithm

Rietveld Quantitative Analysis of Carbides Precipitation in Normalized-tempered 2.2.Cr-1.o-0.2.V Steel

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 922-926页

作者：张永涛张汉谦 school of Materials Science and {1. Shanghai Jiaotong University Research Institute Baoshan Iron & Steel Co.Ltd.

The quantitative determination of the mass fractions of precipitates in steels is very difficult using traditional materials characterization techniques. The Rietveld full-pattern fitting algorithm was introduced to solve this problem. The precipitated multicomponents’ mass fraction of M3C, MC, M7C3 and M2.C6 were evaluated precisely and relatively quickly. It is found evolution of carbides apparently occurs during tempering at high temperatures, and a two-step transformation mechanism is proposed for M7C3 during early tempering treatment. The method is an effective way on the investigation of precipitation kinetics, which may play a promising role in propertities’ enhancement and design of the heat-resistant steels.

关键词： 2.2.Cr-1.o-0.2.V steel rietveld quantitative analysis precipitates

Codes From Strongly Regular (α,β)-reguli

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Journal of shanghai Jiaotong university(Science) 2008年第4期13卷 491-494页

作者：李秀丽 Department of Mathematics Shanghai Jiaotong University

Strongly regular (α,β)-reguli are a class of incidence structures with given conditions which were introduced by Hamilton and Mathon. We introduce two classes of codes constructed from strongly regular (α,β)-regul... 详细信息

关键词： two-weight codes strongly regular (α,β)-reguli

Predicting bioconcentration factor values of organic pollutants based on medv descriptors derived QSARs

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Science china Chemistry 2007年第5期50卷 587-592页

作者： CUI ShiHai1,2. YANG Jing1, LIU ShuShen2.3 & WANG LianSheng2.1 College of Chemistry and Environment, Nanjing Normal University, Nanjing 2.0097, china 2.State Key Laboratory of Pollution Control and Resources Reuse, school of the Environment, Nanjing University, Nanjing 2.0093, china 3 Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and engineering, tongji University, shanghai 200092, china 1. College of Chemistry and Environment Nanjing Normal University Nanjing 210097 China 2. State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China 3. Key Laboratory of Yangtze Aquatic Environment Ministry of Education College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The molecular electronegativity-distance vector (MEDV) is employed todescribe the chemical structure of organic *** linear relationships between themolecular descriptors and BCF values are developed by best subset regression and partial leastsquare regression *** main structural factors influencing the bioactivities are -CH2.-X,-Cnot 2.and q2.(LOO) present good estimation ability and stabilityof *** prediction power for external samples is validated by the model developed from thetraining set.

关键词： POPs, BCF, MEDV, QSAR

The protection effect of β-CD on DNA damage induced by ultrafine TiO_2

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Science china Chemistry 2007年第2期50卷 272-275页

作者： ZHU RongRong,WANG ShiLong,SUN XiaoYu,ZHANG Rui & YAO SiDe school of Life Science and Technology,{1. University,{2.,china 1. school of Life Science and Technology Tongji University Shanghai 200092 China

Under the photocatalysis of 365 nm ultraviolet radiation,ultrafine TiO2.caused the oxidative damage of Teasy plasmid DNA. The damage was determined by gel-electrophoresis. Then,a different dose of β-CD was added to the reaction,and the damage was restrained. The rate of damage restraining reached 97% when the mass of β-CD was 4 times as that of TiO2. Through UV scan and IR spectroscopy,it was found that the Ti-O of ultrafine TiO2.was bound with -OH of β-CD cavum and the -OH on the surface of ultrafine TiO2.disappeared,so the formation of ?OH was controlled. The ultrafine TiO2.has been widely used,but it was determined to be carcinogenic by some research. The protection effect of β-CD to DNA in the molecular level takes a new look on the surface modification of nano particles to decrease the toxic effect.

关键词： β-CD ultrafine TiO2 plasmid DNA oxide damage bond reaction damage restrain