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Science China(Technological Sciences) 2006年第2期49卷 172-187页

作者： LIU Rangsu1, LIU Fengxiang1, DONG Kejun1, ZHENG Caixing1, LIU Hairong2. PENG Ping2.& LI Jiyong3.1. department of Physics,{2., changsha {3. China 2. department of Material Science and Engineering,{2., changsha {3. China 3. department of chemistry,{2., changsha {3. China department of Physics Hunan University

A molecular dynamics simulation study has been performed for a large systemconsisting of 100000 liquid metal Al atoms to investigate the formation and magic numbercharacteristics of the cluster configurations formed during the rapid solidification processes. Thecluster-type index method (CTIM) has been adopted to describe various types of clusterconfigurations. The results indicate that the icosahedral clusters (12.0 12.0) and theircombinations play the most important role in the rnicrostructure transitions during solidificationprocesses; for the cluster configurations of different levels formed by various combinations withdiffering numbers of basic clusters, their size distributions possess obvious magic number sequencewhich is in turn as 13.13., 19(2.), 2.-2.(2.), 3.-3.(3.), 3.-40, 43.44, 48..., (those in bracket arethe corresponding value in liquid state); the magic numbers correspond to the peak value positionsof the cluster numbers for corresponding level formed with various combinations by 1, 2. 3. 4, 5, 6,7, ...basic clusters, respectively. This magic number sequence is in good agreement with theexperimental results obtained by Harris et al. At the same time, this simulation study also gives ascientific and reasonable explanation to these experimental results.

关键词： liquid metal, solidification processes, cluster configuration, magic numbers, computer simulation.

Effect of static magnetic field on activity of immobilized α-amylase

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Chinese Science Bulletin 1997年第2期42卷 127-130页

作者： YAN Liushui, ZHU Yuanbao, HE-Shuang’e and CAO Zhixiang1 department of Chemical Engineering, Nanchang Institute of Aeronautical Technology, Nanchang 3.003., China 2. department of chemistry and Chemical Engineering,{3., changsha 410082. China department of Chemical Engineering Nanchang Institute of Aenwututical Techndogy Nanchang China department of chemistry and Chemical Engineering Hunan University Changsha China

BIOLOGICAL effect of magnetic field is one of the three major subjects of contemporary biomagnetism, and is also the basis of applied biomagnetism. In order to explore magnetic biological effects, the influence of various sorts of magnetic field on many living systems as well as their different constructural levels has been extensively studied. However, only a few studies with in vitro enzyme have been reported, and few researches concerning the influence of magnetic field on immobilized enzyme reactions have been published. This note describes

关键词： static magnetic field immobilized α-amylase enzyme activity oscillatory behaviour.

Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

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Science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong department of Applied Physics, hunan university, {2. {3. China College of Materials Science and Engineering, hunan university, {2. {3. China College of chemistry and Chemical Engineering, hunan university, {2. {3. China department of Applied Physics Hunan University Changsha 410082 China College of Materials Science and Engineering Hunan University Changsha 410082 China College of chemistry and Chemical Engineering Hunan University Changsha 410082 China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12.0 12.0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

Study on H atoms diffusion and adsorption properties of MgH_2.V systems

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Science China(Technological Sciences) 2008年第7期51卷 979-988页

作者： ZHOU DianWu1,2. LIU JinShui3.& PENG Ping3.1 State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,{2., changsha 410082. China 2.College of Mechanical and Automatic Engineering,{2., changsha 410082. China 3.College of Materials Science and Engineering,{2., changsha 410082. China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University College of Mechanical and Automatic Engineering Hunan University College of Materials Science and Engineering

Based on experimental results that VH0.81/MgH2.interface was found during the process of mechanically milling MgH2.5at.%V nanocomposite, H atoms diffusion and adsorption properties of MgH2.V systems have been investigated by using a first-principles plane-wave pseudopotential method based on the density functional theory. The results are as follows. When VH/MgH2.interface is formed due to V alloying MgH2.phase, the vacancy formed by H atoms near VH phase region is more stable than that without V alloying, while vacancy near MgH2.phase region is less stable than that without V alloying. During the process of H atoms diffusion after V alloying, the max migration barrier energy of H atoms in MgH2.V systems is reduced compared with that of MgH2.phase, which means that H atoms diffuse easily. When H diffuses into VH from MgH2.across VH/MgH2.interface, among three substitutions such as the replacement of H for V vacancy, or interstitial site or V atoms, the replacement of H for V vacancy has the strongest diffusion ability, next interstitial site, and finally V atoms site. As far as H adsorbed on different surfaces of VH phase is concerned, physical adsorption is carried out more easily than chemical adsorption, and the behavior of H atoms adsorbed on the surface near VH phase region can be found more easily than that near MgH2.phase region.

关键词： plane-wave pseudopotential theory magnesium hydride diffusion adsorption

Molecular dynamics simulation of thermal stability of nanocrystalline vanadium

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Science China(Technological Sciences) 2006年第4期49卷 400-407页

作者： WEI Mingzhi1, XIAO Shifang1, YUAN Xiaojian2.& HU Wangyu1,2.1. Material Science and Engineering College, hunan university, changsha {2. China 2. {3. of Applied Physics, hunan university, changsha {2. China Material Science and Engineering College Hunan University department of Applied Physics Hunan University

The microstructure and thermal stability of nanocrystalline vanadium with an average grain size ranging from 2.86 to 7.50 nm are calculated by means of the analytic embedded-atom method and molecular dynamics. The grain boundary and nanocrystal- line grain atoms are differentiated by the common neighbor analysis method. The results indicate that the fraction of grain boundary increases with the grain size decreasing, and the mean energy of atoms is higher than that of coarse crystals. The thermal-stable tem- peratures of nanocrystalline vanadium are determined from the evolution of atomic energy, fraction of grain boundary and radial distribution function. It is shown that the stable tem- perature decreases obviously with the grain size decreasing. In addition the reasons which cause the grain growth of nanocrystalline vanadium are discussed.

关键词： nanocrystalline, embedded-atom method, molecular dynamics, thermal stability.

Research on Uncertainties in Evaluation Indicator System for Ecological Residential Community

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湖南大学学报（自然科学版） 2009年第S1期36卷 177-181页

作者： JIAO Sheng1,GUAN Chen-yin2.ZENG Guang-ming3.LIU Jian-long1,Zhou Jian-fei3.1.College of Architecture,{2. university,changsha,{2. 410082.China 2.Beijin School,{2. university of Commerce,changsha,{2. 4102.9,China 3.College of Environmental Science and Engineering,{2. university,changsha,{2. 410082.China) College of Architecture Hunan University Changsha 410082 China Beijin School Hunan University of Commerce Changsha 410209 China College of Environmental Science and Engineering Hunan University Changsha 410082 China

In the process of evaluating,the weights of indicators are firstly determined by AHP and Delphi methods;and the values of indicators are normalized by grey correlative coefficient method.A suit of means were put forward,by which a qualitative and quantitative evaluation indicator system suitable for the situation of China and uncertainties can be *** idiographic and operable methods and process were *** the principle of elasticity,hiberarchy and maneuverability,a three-layer evaluation indicator system was established by AHP in Jiuyi ecological residential community,which includes 5 subsystems and 2. *** weights of indicators are measured by AHP and expert estimate and their best indicators values up to par were determined by fuzzy mathematics and *** whole evaluation indicator system not only has an active and practical effect on estimating ecological residential community,but also guides ecological residential community planning.

关键词： ecological residential community evaluation indicator system ecological risk evaluation uncertainty fuzzy mathematics grey correlative coefficient

SYNTHESIS　OF　1－（2.AMINOETHYL）　PIPERAZINE　RESIN　AND　ITS　ADSORBABILITYFOR　NOBLE　METALLIC　IONS

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中国有色金属学会会刊：英文版 1995年第1期5卷 57-62页

作者： Yuan Xingzhong(Institute of Enviromental Protection , hunan university, changsha {2. Chen Yiyong({3. of chemistry , Hangzhou university , Hangzhou 3.002.) hunan UNIV INST ENVIRONM PROTECTCHANGSHA 410082PEOPLES R CHINA HANGZHOU UNIV DEPT CHEMHANGZHOU 310028PEOPLES R CHINA

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关键词： aminoethyl) piperazine resin(AEPZR) adsorption noble metallic ions

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science China(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2. ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. department of chemistry, Qingdao university, Qingdao 2.6071, China 2. department of chemistry, Tsinghua university, Beijing 100084, China 3. department of Physics, Qingdao university, Qingdao 2.6071, China department of Physics Qingdao University

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

An index-split Bloom filter for deep packet inspection

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Science China(Information Sciences) 2011年第1期54卷 23-37页

作者： HUANG Kun1 & ZHANG DaFang1,2.1School of Computer and Communication,hunan university,{2. {3.China 2.School of Software,hunan university,{2. {3.China School of Computer and Communication Hunan University School of Software Hunan University

Deep packet inspection(DPI)scans both packet headers and payloads to search for predefined *** link rates and traffc volumes of Internet are constantly growing,DPI is facing the high performance challenge of how to achieve line-speed packet processing with limited embedded *** recent trie bitmap content analyzer(TriBiCa)suffers from high update overhead and many false positive memory accesses,while the shared-node fast hash table(SFHT)suffers from high update overhead and large memory *** paper presents an index-split Bloom filter(ISBF)to overcome these *** a set of off-chip items,an index of each item is split apart into several groups of constant bits,and each group of bits uses an array of on-chip parallel counting Bloom filters(CBFs)to represent the overall off-chip *** an item is queried,several groups of on-chip parallel CBFs constitute an index of an off-chip item candidate for a ***, we propose a lazy deletion algorithm and vacant insertion algorithm to reduce the update overhead of ISBF, where an on-chip deletion bitmap is used to update on-chip parallel CBFs,not adjusting other related off-chip *** ISBF is a time/space-effcient data structure,which not only achieves O(1)average memory accesses of insertion,deletion,and query,but also reduces the memory *** results demonstrate that compared with the TriBiCa and SFHT,the ISBF significantly reduces the off-chip memory accesses and processing time of primitive operations,as well as both the on-chip and off-chip memory sizes.

关键词： network security packet processing deep packet inspection hash table Bloom filter

Piezoelectric transmission spectroelectrochemistry with a normal piezoelectric quartz crystal as an optically-transparent electrode

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Chinese Journal of chemistry 1994年第5期12卷 425-431页

作者： XIE, Qing-Ji PANG, Xiao-Yong NIE, Li-Hua YAO, Shou-Zhuo department of chemistry and Chemical Engineering,{2., {3., hunan 410082. China department of chemistry and Chemical Engineering Hunan University Changsha Hunan 410082 China

Piezoelectric transmission spectroelectrochemistry (PTSEC), i.e., the combination of electrochemistry and spectroelectrochemistry (SEC) with electrochemical quartz crystal microbalance (EQCM) technique is reported by using a normal piezoelectric quartz crystal (PQC) as an optically-transparent electrode (OTE). A theoretical relationship between the PQC response and the spectroelectrochemical response is derived and used to estimate the apparent molar absorptivity of the absorbing species deposited on the OTE on the PQC surface. The complex of copper with aspartic acid is used to test this new PQC-SEC technique. Results show that the combination of three such diverse techniques provides a very useful methodology for studying electrode processes and electrode surface characteristics in situ.

关键词： Piezoelectronic transimission spectroelectrochemistry optically-transparent electrode electrochemical quartz crystal microbalance copper aspartic acid.