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The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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Science China(Physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1.2.& YUAN XianBao1.{1.1.College of Science, China Three Gorges University, Yichang 44{1.02. China 2.{2. of Physics and Technology, Wuhan University, Wuhan 4{1.072. China {1.Institute of Particle Physics, Central China Normal University, Wuhan 4{1.070, China 1. College of Science China Three Gorges University Yichang 443002 China 2. {1. of Physics and Technology Wuhan University Wuhan 430072 China 3. Institute of Particle Physics Central China Normal University Wuhan 430070 China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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Science China(Information Sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1.2.LI Gang {1.& GENG HuanTong 1.1.school of Computer and Software,Nanjing University of Information Science & Technology,Nanjing 2.0044,China 2.Network Information Center,Nanjing University of Information Science & Technology, Nanjing 2.0044,China {1.school of Mathematics and Physics,Nanjing University of Information Science & Technology,Nanjing 2.0044,China 1. school of Computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. Network Information Center Nanjing University of Information Science & Technology Nanjing 210044 China3. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 1. representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 1. instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

Organic Solvents Mediate Self-assembly of GAV-9 Peptide on Mica Surface

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 285-289页

作者： Hai LI~(1.3. Feng ZHANG~1.Yi ZHANG~1. Jianhua HE~1.Jun HU~(1.{1. 1.Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai {1.1.00,China {1.Bio-X Life Sciences Research Center.College of Life Science and Biotechnology,Shanghai Jiaotong University,Shanghai {1.003.,China 3.Graduate school of the Chinese Academy of Sciences,Beijing 1.0049,China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800 China Graduate school of the Chinese Academy of SciencesBeijing 1.0049 China Bio-X Life Sciences Research Center College of Life Science and Biotechnology Shanghai Jiaotong UniversityShanghai 200030 China

Self-assembly of peptides into fibrils and other morphologies has attracted much attention inmany fields,especially in nanofabrication,pathology and *** this paper,self-assembly of GAV-9peptide in organic solvents,ethanol and acetone,was investigated using atomic force microscopy(AFM)and attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR).The results indicatedthat GAV-9 self-assembled into various nanostructures in both solvents after deposited and evaporated *** with β-sheet conformation were observed in both solvents when the peptide concentrationwas higher than 2.0 μ***,ordered fibrils with β-sheet conformation were formed in ethanol,butnot in acetone,with a peptide concentration ranging from 7 μM to 2. μ*** attribute the formation ofvarious nanostructures to the different physicochemical properties of the polar organic solvents on the self-assembly of GAV-9 peptide.

关键词： self-assembly GAV-9 peptide organic solvents ATR-FTIR AFM

Comprehensive Control on Microstructures and Properties of Medium Carbon V-N Microalloyed Steel Seamless Oil-Well Tubes of Hot-Rolling Non-Quenched/Tempered

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Journal of Iron and Steel Research International 2011年第S1期18卷 696-700页

作者： LIU Sheng-xin 1.2.LIU Guo-quan 2.CHEN Yong 1.ZHANG Yong-gang 3.HUANG Jian-kai 3.(1.{2. of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450002.Hennan China 2.{2. of Materials Science and Engineering,University of Science and Technology Beijing,1.0083.China 3.Wuxi Seamless Steel Tube Company Ltd,Wuxi 2.402.,Jiangsu China) Zhengzhou Univ Sch Mat Sci & Engn Zhengzhou 450002 Hennan Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Wuxi Seamless Steel Tube Co Ltd Wuxi 214026 Jiangsu Peoples R China

The relationship between microstructures and mechanical properties of a medium carbon V-N microalloyed steel used for N80 seamless oil-well tubes of hot rolling non-quenched/tempered (non-Q and T) was *** results have shown that volume percentages of upper bainite,modified bainite and ferrite have a decisive influence on impact energies of steel *** the total volume percentage of bainite is larger than 5%,the impact energy of tubes can not satisfy with the industrial ***,if the total volume percentage of bainite is smaller than 5%,then the impact energy of steel tubes enhances with volume percentage of ferrite *** final microstructures have closely relation with tube billet quality,controlled cooling temperature after tube rolling and cooling method after *** quality of medium carbon V-N microalloyed steel for non-Q and T oil-well tubes can be produced through comprehensive control of microstructures and mechanical properties in sub-procedures,especially for tube billet quality and controlled cooling parameters.

关键词： medium carbon V-N microalloyed steel N80 grade seamless oil-well tube microstructure mechanical property

Two-Sublattice Thermodynamic Model on Carbonitride Precipitation in Microalloyed Steels Bearing Nb-V-Ti

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Journal of Iron and Steel Research International 2011年第S1期18卷 271-277页

作者： XIANG Song 1.3.LIU Guo-quan {1.(1.school of Materials and Metallurgy,Guizhou University,Guiyang 550003.Guizhou,China {1.school of Materials Science and Engineering,University of Science and Technology,Beijing,Beijing 1.0083.China 3.The Key Laboratory for Mechanical Behavior and Microstructure of Materials,Guizhou Province,Guiyang 550003.Guizhou,China) Guizhou Univ Sch Met & Mat Guiyang 550003 Guizhou Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Key Lab Mech Behav & Microstruct Mat Guiyang 550003 Guizhou Peoples R China

Based on the two sublattice model of the regular solution,one being metal atom sublattice and another being interstitial atom sublattice,a thermodynamic model for the precipitates of niobium carbonitride,vanadium carbonitride and titanium carbonitride was established to study the starting-temperature of precipitates and the austenite compositions at given temperature in a low carbon *** calculation results show that starting-temperature of the precipitation of niobium carbonitride,vanadium carbonitride and titanium carbonitride are 1.00℃,92.℃ and 1.1.0℃,respectively,the mole fraction of carbonitride precipitates is 8.65×1.-4 in the 0.05{1.-0.002.N-1.2.Mn-0.008S-0.0{1.Al-0.046Nb-0.008Ti0.02.V-Fe *** the N content is from 0.002.% to 0.0056%,the starting-temperature of the precipitation of the titanium carbonitride changes from 1.1.0℃ to 1.{1.℃.And the C content is from 0.05{1. to 0.07%,the startingtemperature of the precipitation of the titanium carbonitride hardly changes,but the atomic fraction of niobium in the carbonitride obviously increases.

关键词： microalloyed steel carbonitride precipitation two sublattice model thermodynamics

Secure multi-party computation protocol for sequencing problem

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Science China(Information Sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1.2.SHI GuiHua 1.& YAO ZhengAn {1.1.school of Mathematics and Information Science,Guangzhou University,Guangzhou 51.006, China 2.tate Key Laboratory of Information Security, Institute of Software Science,Chinese Academy of Sciences,Beijing 1.0080,China {1.school of Mathematics and Computational Science,Sun Yat-Sen University,Guangzhou 51.2.5,China 1. school of Mathematics and Information Science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100080 China3. School of Mathematics and Computational Science Sun Yat-Sen University Guangzhou 510275 China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1./2.participants, and an active adversary that can corrupt at most t 3.*** simplest sequencing problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

On the number of B_(π')-characters in a nilpotent π-block

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Science China Mathematics 2008年第1期51卷 1-4页

作者： HAI JinKe~(1.) & ZHU YiXin~2.1.{1. of Mathematical Sciences, Qingdao University, Qingdao 2.6071. China 2.{1. of Mathematical Sciences, Capital Normal University, Beijing 1.00{2., China school of Mathematical Sciences Qingdao University Qingdao 266071 China school of Mathematical Sciences Capital Normal University Beijing 100037 China

Brouéand Puig set the definition of nilpotent p-blocks, stated the existence of such blocks, and then proved that there is a unique Brauer character in a nilpotent p-block. The present paper, based on the works of Slattery and Robinson, generalizes the above idea to theπ-block theory of aπ-separable group, defines the nilpotency of aπ-block, and proves that there is a unique B_(π')-character in a nilpotentπ-block.

关键词： π-separable groups π-blocks π-subpairs nilpotentπ-blocks

The contribution of cis-regulatory elements to head-to-head gene pairs' co-expression pattern

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Science China(Life Sciences) 2009年第1期52卷 74-79页

作者： HAO Pei1.2.YU Yao2.3.ZHANG XiaoYan4,TU Kang2.FAN HaiWei2.& ZHONG Yang1.1.school of Life Sciences,Fudan University,Shanghai 2.043.,China 2.Bioinformatics Center,Key Lab of Systems Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 2.003.,China 3.Shanghai Center for Bioinformation Technology,Shanghai 2.02.0},China 4 school of Life Sciences,Tongji University,Shanghai 2.0092.China 1. school of Life Sciences Fudan University Shanghai 200433 China 2. Bioinformatics Center Key Lab of Systems Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China 3. Shanghai Center for Bioinformation Technology Shanghai 200235 China 4. school of Life Sciences Tongji University Shanghai 200092 China

Transcription regulation is one of the most critical pipelines in biological process,in which cis-elements play the role as gene expression *** attempt to deduce the principles underlying the co-expression of "head-to-head" gene pairs by analyzing activities or behaviors of the shared cis-elements.A network component analysis was performed to estimate the impact of cis-elements on gene promoters and their activities under different *** discoveries reveal how biological system uses those regulatory elements to control the expression pattern of "head-to-head" gene pairs and the whole transcription regulation system.

关键词： transcription regulation cis-elements "head-to-head" gene pairs

Influence of Mg5Ga2.compound on microstructures and electrochemical properties of Mg-5%Hg-2.%Ga alloy

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Progress in Natural Science:Materials International 2011年第1期21卷 73-79页

作者： Yan FENG~1.Ri-chu WANG~1.Chao-qun PENG~1.Hui-ping TANG~2.Hai-yan LIU~2.1.school of Materials Science and Engineering,Central South University,Changsha 41.083.China 2.Northwest Institute for Non-ferrous Metals Research,Xi'an 71.01.,China [a] school of Materials Science and Engineering Central South University Changsha 410083 China [b] Northwest Institute for Non-ferrous Metals Research Xi'an 710016 China

The Mg-5%Hg-2.%Ga（mole fraction） alloy was *** at 57{1.67{1.K for different times was carried out to ensure the fine dispersion of the *** electron microscopy（SEM）,X-ray diffractometry（XRD） and energy spectrum analysis（ESA） were employed to characterize the microstructures and phases of the Mg-5%Hg-2.%Ga *** electrochemical and corrosion behaviors of the above alloy were studied by potentiodynamic,galvanostatic and electrochemical impedance spectroscopy（EIS） *** relationship between the Mg5Ga2.ompound and the electrochemical properties of the Mg-5%Hg-2.%Ga alloy was *** results demonstrate that the heat treatment at 57{1.67{1.K for 2. h accelerates the growth of the intergranular eutectic Mg-Mg5Ga2.nd the heat treatment for 2.0 h prompts the transition of eutectic to dispersed linear Mg phase and *** transition enhances the electrochemical activity and corrosion resistance of the Mg-5%Hg-2.%Ga *** the galvanostatic tests with current density of 1.0 mA/cm2.the most negative potential,-1.991.V, occurs in the sample aged for 2.0 *** largest corrosion current density of 44.{1. mA/cm2.ccurs in the sample aged for 2. h.

关键词： Mg-Hg-Ga alloys anodic behavior Mg5Ga2.phase intergranular corrosion