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N^+离子注入Ti-4Al-2.合金的表面分析研究

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四川大学学报（自然科学版） 2004年第4期41卷 784-787页

作者：邓炯封向东吴继红王治国祖小涛四川大学物理系成都610064 电子科技大学物理电子学院应用物理系成都610054

作者采用 3× 1 0 1 7/cm2.和 8× 1 0 1 7/cm2.两种注量对Ti 4Al 2.合金样品进行了N+离子注入 ,N离子能量 75keV ,在注入过程中样品温度控制在 2.0 0℃以下 .对注入前后的样品进行了X射线衍射 (XRD)以及光电子能谱 (XPS)分析 .由XRD... 详细信息

作者采用 3× 1 0 1 7/cm2.和 8× 1 0 1 7/cm2.两种注量对Ti 4Al 2.合金样品进行了N+离子注入 ,N离子能量 75keV ,在注入过程中样品温度控制在 2.0 0℃以下 .对注入前后的样品进行了X射线衍射 (XRD)以及光电子能谱 (XPS)分析 .由XRD衍射谱表明 ,离子注入后有新相TiN和TiO2.生成 .由XPS宽程扫描谱表明 ,注入后样品表面主要为Ti,C ,N和O .对Ti2.p和N1s的XPS窄程扫描谱也证明 ,离子注入后致使合金近表面形成了TiN和TiO2..

关键词： Ti-4Al-2.合金离子注入 XRD XPS

Special Issue for the 50th Anniversary of the Founding of University of electronic science and {2. of china

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Journal of electronic science and {2. of china 2006年第3期4卷 I0001-I0002页

作者： Journal of electronic science and {2. of china

The special issue of this Journal has been organized for the celebration of the 50th anniversary of the founding of University of electronic science and {2. of china （UESTC）.

关键词： Special Issue for the 50th Anniversary of the Founding of University of electronic science and {2. of china

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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science china Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1 SU Chun~2.& ZENG Yong~1 1. School of Management and School of Applied Mathematics,University of electronic science and {2. of china,Chengdu 610054,china 2. Department of Statistics and Finance,University of science and {2. of china,Hefei 2.002.,china 1. School of Management and School of Applied Mathematics University of Electronic Science and Technology of China 610054 Chengdu China 2. Department of Statistics and Finance University of Science and Technology of China 230026 Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

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 Engineering, Northwestern Polytechnical University, Xi’an 710072. china 2. College of Materials science and Engineering, Henan University of science and technology, Luoyang 471003, china 1. College of Materials science and Engineering Northwestern Polytechnical University 710072 Xi’an China 2. College of Materials science and Engineering 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.

Experimental study on fire smoke movement in a multi-floor and multi-room building

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science china(Technological sciences) 2005年第3期48卷 292-304页

作者： ZHONG Maohua 1, 2., LI Peide 2., LIU Tiemin 1 , WEI Xing 1, 2.& LIAO Guangxuan 2.1. National Center of Safety science and technology, State Administration of Work Safety, Beijing 10002., {2. 2. State Key Laboratory of Fire science, University of science and technology of {2., Hefei 2.002., {2. 1. National Center of Safety science and technology State Administration of Work Safety 100029 Beijing China 2. State Key Laboratory of Fire science University of Science and Technology of China 230026 Hefei China

Fire smoke movement of multi-floor and multi-room (MFMR) fire was studied at the model test building in State Key Laboratory of Fire science (SKLFS). The ingredient, temperature, air pressure difference and air velocity of smoke were measured and analyzed. Meanwhile, the hazard of smoke ingredient to exposed occupants was analyzed based on the national standard, Occupational Exposure Limit for Hazardous Agents in the Workplace (GBZ2.2.02.. The experimental results showed that the maximum temperature difference in MFMR fire was located along the vertical height from the fire source. With the spreading and diffusion of smoke, the temperature of smoke layer would tend to be no difference. In the fire of woodpile and kerosene, the main smoke ingredients such as SO 2., CO and CO 2.would first exceed human’s average physiological limit, while smoke ingredients such as NO and NO 2.would come behind. Because of the higher fluctuation range and frequency of air pressure difference of smoke in multi-layer building fire, the fire smoke would spread around everywhere of the passageway and made the human evacuation more difficult.

关键词： multi-floor and multi-room,fire experiment,smoke spread,smoke toxicity.

Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application science and technology, Harbin University of science and technology, Harbin 150080, china 2. Department of Precision Instruments, Tsinghua University, Beijing 100084, china) School of Application science and technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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science china Chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2.& HU Weixiao1 1. Department of Pharmaceutical science, Zhejiang University of technology, Hangzhou 310032. {2. 2. Department of Applied Chemistry, Zhejiang Institute of science and technology, Hangzhou 310033, {2. 1. Department of Pharmaceutical science Zhejiang University of Technology 310032 Hangzhou China 2. Department of Applied Chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

Real estate appraisal system based on GIS and BP neural network

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中国有色金属学会会刊：英文版 2011年第S3期21卷 626-630页

作者： LIU Xiao-sheng1, DENG Zhe1, WANG Ting-li2.1. School of Architecture and Survey Engineering, Jiangxi University of science and technology, Ganzhou 341000, {2. 2. School of Applied science, Jiangxi University of science and technology, Ganzhou 341000, {2. [a] School of Architecture and Survey Engineering Jiangxi University of Science and Technology Ganzhou 341000 China [b] School of Applied science Jiangxi University of Science and Technology Ganzhou 341000 China

For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2.08. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system.

关键词： BP neural network GIS hedonic price real estate appraisal

Structure and Magnetic Properties of Ni-doped ZnO Powder

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Journal of Wuhan University of technology(Materials science) 2010年第5期25卷 770-773页

作者：高放赵俊 Department of electronic science and {2. Huazhong University of Science and Technology

Ni-doped ZnO nanopowder （Zn0.98Ni0.2.） was synthesized by improved coprecipitation method. The average particle size of the powder was estimated to be 50 nm. The powder was then processed by thermal treatment. Samples were annealed at 1 073, 1 2.3, and 1 473 K, respectively. The solubility of NiO in ZnO and the lattice parameters of ZnO both increased with the temperature. The magnetic property of the doped samples was examined, and hysteresis loops were got. The results showed all the samples were ferromagnetic, while powder processed at 1 2.3 K for 4 h got a highest saturation magnetization （Ms） of 0.0457 emu/g. Also, magnetic properties were related to the grain size of the powder.

关键词： ferromagnetism diluted magnetic semiconductor Ni-doped ZnO coprecipitation solid state reaction