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science china(Physics,{2.s & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2.HE Deyan2.LIU Jun2. MA Jiantai3 1. Key Laboratory of Opto-electronic technology and Intelligent Control, Ministry of Education,{2. Jiaotong university,{2. 730070, china 2. School of Physical science and technology,{2. university,{2. 730000, china 3. School of Chemistry and Chemistry {12.,{2. university,{2. 730000, china 1. Key Laboratory of Opto-electronic technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University 730070 Lanzhou China 2. School of Physical science and technology Lanzhou University 730000 Lanzhou China 3. School of Chemistry and Chemistry engineering Lanzhou University 730000 Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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science china(Physics,{2.s & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2. TANG Jun 2., ZHANG AiHua 3 & JIA Ya 2.1 Department of Physics, lanzhou university of {2., lanzhou 730050, china 2.Department of Physics, Central china Normal university, Wuhan 430079, china 3 college of Electrical and Information engineering, lanzhou university of {2., lanzhou 730050, china 1. Department of Physics Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

D(β)-vertex-distinguishing total coloring of graphs

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science china Mathematics 2006年第10期49卷 1430-1440页

作者： ZHANG Zhongfu,LI Jingwen,CHEN Xiang’en,YAO Bing, WANG Wenjie & QIU Pengxiang Institute of Applied Mathematic, lanzhou Jiaotong university, lanzhou 730070, china college of Mathematics and Information science, Northwest Normal university, lanzhou 730070, china college of Information and Electrical engineering, lanzhou Jiaotong university, lanzhou 730070, china Institute of Applied Mathematic Lanzhou Jiaotong University Lanzhou 730070 China college of Mathematics Information science Northwest Normal University Lanzhou 730070 China college of Information Electrical engineering Lanzhou Jiaotong University Lanzhou 730070 China

A new concept of the D(β)-vertex-distinguishing total coloring of graphs, i.e., the proper total coloring such that any two vertices whose distance is not larger than β have different color sets, where the color set of a vertex is the set composed of all colors of the vertex and the edges incident to it, is proposed in this paper. The D(2.-vertex-distinguishing total colorings of some special graphs are discussed, meanwhile, a conjecture and an open problem are presented.

关键词： graph, total coloring, D(β)-vertex-distinguishing total coloring, D(β)-vertexdistinguishing total chromatic number.

Development of Expert Controller for Plasma Spraying Process

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材料热处理学报 2004年第5B期25卷 783-786页

作者： LIChun-xu CHENKe-xuan LIHe-qi LIDe-wu EducationMinistryKeyLab.ofAdvancedProcessingtechnologyforNon-ferrousMaterials LanzhouUniversityofScience＆TechnologyLanzhouChina collegeofMaterialsscienceand{2. LanzhouUniv.ofScience＆TechnologyLanzhouChina

Aiming at the plasma spraying process control, the control system model is developed on the basis of analyzing control parameters and coating properties and their correlation, and the corresponding control method and regulations are also given. With the developed expert controller for plasma spraying process, stable spraying can be realized using ordinary spraying powder and the coating of compaction, homogeneity and high bonding strength can be obtained.

关键词：等离子喷涂控制器粉末熔炼镀层厚度

On adjacent-vertex-distinguishing total coloring of graphs

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science china Mathematics 2005年第3期48卷 289-299页

作者： ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang college of Mathematics and Information science, Northwest Normal {2., lanzhou 730070, china Department of Computer, lanzhou Normal college, lanzhou 730070, china Institute of Applied Mathematics, lanzhou Jiaotong {2., lanzhou 730070, china college of Information and Electrical engineering, lanzhou Jiaotong {2., lanzhou 730070, china Institute of Applied Mathematics, Chinese Academy of sciences, Beijing 100080, china 1. college of Mathematics and Information science Northwest Normal University 730070 Lanzhou China 2. Department of Computer Lanzhou Normal College 730070 Lanzhou China 3. Institute of Applied Mathematics Lanzhou Jiaotong University 730070 Lanzhou China 4. college of Information and Electrical engineering Lanzhou Jiaotong University 730070 Lanzhou China 5. Institute of Applied Mathematics Chinese Academy of Sciences 100080 Beijing China

In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number... 详细信息

关键词： graph, proper total coloring, adjacent-vertex-distinguishing total coloring, adjacent-vertex-distinguishing total chromatic number.

Topological chirality and achirality of the closed circular DNAs

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Chinese science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. Department of Chemical Physics, university of science and {2. of china, Hefei 2.002., china 2. Department of Chemistry, lanzhou university, lanzhou 730000, china Depaitment of Chemical Physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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science china Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3 & YE Xianren2.1. Resources and Environmental School, lanzhou university, lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of sciences, lanzhou 730000, china 3. college of Resources science & technology, Beijing Normal university, Beijing 100875, china 1. Resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. college of Resources science & {2. Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3He from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. college of Materials science and {2., Northwestern Polytechnical university, Xi’an 710072. china 2. college of Materials science and {2., Henan university of science and technology, Luoyang 471003, china 1. college of Materials science and {2. Northwestern Polytechnical University 710072 Xi’an China 2. college of Materials science and {2. Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Improvements on radiation-hardened performance of static induction transistor

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science china(Information sciences) 2010年第5期53卷 1089-1096页

作者： WANG YongShun 1 , LUO XianLiang 1 , LI HaiRong 2., WANG ZiTing 1 , WU Rong 1 , ZHANG CaiZhen 2.& LI SiYuan 2.1 School of electronic and Information engineering,{2. Jiaotong university,{2. 730070, china 2.Institute of Microelectronics, School of Physical science and technology,{2. university,{2. 730000, china 1. School of electronic and Information engineering Lanzhou Jiaotong University Lanzhou 730070 China2. Institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou 730000 China

The radiation-hardened performances of static induction transistor (SIT) have been studied in depth in this paper. The effects of radiation of electron beam on the I-V characteristics, carrier distribution and potential distribution in the channel of SIT have been represented. A large number of electron-hole pairs are generated in the depletion region of reversely biased gate-channel PN junction. The radiation-generated electrons drift towards the drain region at high positive potential, while generated holes flow into gate region biased to the lowest potential. With the accumulation of holes in gate region, the gate potential is boosted, resulting in a decrease in the height of potential barrier in channel, and an increase in drain current. I-V characteristics of SIT in the presence of radiation have been theoretically derived, and compared with experimental results. With the increase in thickness of epitaxial layer, the radiation-hardened capability of SIT is continuously improved until the optimum thickness of 2. μm is reached. The optimum matching relationship among geometric, material and technological parameters has been represented to acquire excellent radiation-hardened performances of SIT.

关键词： static induction transistor radiation-resistant potential barrier electron beam radiationgenerated carriers