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Electronic Structure of Doped Trans-Polyacetylene

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wuhan {1. Journal of Natural {2.s 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1.2. Zhuang Wei 2. wang Jun 2.1. {1. {2. Journals Press,{1. 430072.hubei,china 2. School of Physics and technology, {1. {2., {1. 430072.hubei,china wuhan {1. Journals Press Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C2.H2.)+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2.method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

Evaluation Method of Web Site Structure Based on Web Structure Mining

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wuhan {1. Journal of Natural {2.s 2003年第3A期8卷 791-796页

作者： Li Jun\|e 1., Zhou Dong\|ru 2.1. Computer Center,{2. {1., {2. 430072. hubei, china 2. School of Computer,{2. {1., {2. 430072. hubei,china wuhan {1. Computer Center Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The structure of Web site became more complex than before. During the design period of a Web site, the lack of model and method results in improper Web structure, which depend on the designer's experience. From the point of view of software engineering, every period in the software life must be evaluated before starting the next period's work. It is very important and essential to search relevant methods for evaluating Web structure before the site is completed. In this work, after studying the related work about the Web structure mining and analyzing the major structure mining methods (Page\|rank and Hub/Authority), a method based on the Page\|rank for Web structure evaluation in design stage is proposed. A Web structure modeling language WSML is designed, and the implement strategies for evaluating system of the Web site structure are given out. Web structure mining has being used mainly in search engines before. It is the first time to employ the Web structure mining technology to evaluate a Web structure in the design period of a Web site. It contributes to the formalization of the design documents for Web site and the improving of software engineering for large scale Web site, and the evaluating system is a practical tool for Web site construction.

关键词： web structure mining page\|rank web structure evaluation modeling language for web structure

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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science{1.(Technological sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3, wang Guilan1 & ZHENG Qiguang2.1. School of Material {1. and {2., Huazhong university of {1. and {2., wuhan 430074, china 2. Institute of Laser {2. and Engineering, Huazhong university of {1. and {2., wuhan 430074, china 3. Mechanical Engineering College,{1.} university of {2., wuhan 430068, china 1. School of Material science and {1. Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical Engineering College Hubei University of Technology Wuhan 430068 China 2. Institute of Laser technology and Engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Polarity for a Class of Levy Processes

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wuhan {1. Journal of Natural {2.s 2002年第4期7卷 394-398页

作者： Wu Chuan ju 1.2., Liu Lu qin 1.1. School of Mathematics and Statistics, wuhan {1., wuhan 430072. hubei, china 2. College of Urban Construction, wuhan university of science and technology, wuhan 430070, hubei, china wuhan {1. School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. of {2. and technology College of Urban Construction Wuhan Hubei China (GRID:grid.412787.f) (ISNI:***) wuhan {1. School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Polar set of Markov processes is an important concept in probabilistic potential theory, but it is not easy to judge the polarity of the sets. In this paper, we give some results which can be easily used to examine the polarity of the sets whenX t belongs to a special class of Levy processes. We also give a result about polar functions of symmetric stable processes.

关键词： Levy process subordinator (essentially) polar set polar function

Preparation of PLL-PEG-PLL and its application to DNA encapsulation

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science{1. Chemistry 2006年第4期49卷 357-362页

作者： YANG Zigang1. ZHOU Fen1. YUAN Jianjun1. MA Lixin2. ZHAI Chao2.& CHENG Shiyuan1.1. School of Chemistry and Materials science,{1. {2., wuhan 430062. china 2. School of Life science,{1. {2., wuhan 430062. china 1. School of Chemistry and Materials science Hubei University Wuhan 430062 China 2. School of Life science Hubei University Wuhan 430062 China

PLL-PEG-PLL was synthesized by deprotection of the amino group of PLL(Z)-PEG-PLL(Z). The properties of the polyion complex (PIC) micelles comprising of PLL-PEG-PLL and DNA were investigated. The results showed that the core of PIC was formed by PLL and DNA through electrostatic interactions, and PEG was shell of PIC, so PIC micelles in aque- ous medium were homogenous with no precipitation even under the neutral condition, and PIC had the characteristic of stability, which were very important in gene therapy. At the same time, the results showed PLL-PEG-PLL could condense DNA, longer PLL blocks were generally more effective at condensation, and the nuclease resistance of DNA was increased remarkably. PIC was spherical with diameter of 1.―35 nm, which could be easily taken up by cells. Transfection experiments in vitro showed that the DNA encapsulated could be expressed in the cell line SF9.

关键词： poly(L-Lysine), poly(ethylene glycol), block copolymer, DNA, polyion complex micelles (PIC).

Commission Strategy of the Auction House

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wuhan {1. Journal of Natural {2.s 2006年第3期11卷 507-510页

作者： wang Yan~ 1.2.1. College of Economics, Fudan {1., Shanghai 2.0433,{2. 2. School of Mathematics and Statistics, wuhan {1. , wuhan 430072. hubei,{2. College of Economics Fudan University 200433 Shanghai China School of Mathematics Statistics Wuhan University 430072 Wuhan Hubei China

In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders＇ equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.

关键词： auction commission proportion Bayesian equilibrium bidding strategy

Numerical simulations and experimental investigations on transverse effects of two-wave mixing in a photovoltaic photorefractive crystal

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science{1.(Physics,Mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1.2.LIU JinSong1.& {2. ShengLie1.1.{1. National Laboratory for Optoelectronics,School of Optoelectronic {2. and Engineering,Huazhong university of {2. and technology,{1. 430074,china 2.School of {2.,{1. university of technology,{1. 430070,china 1. wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. School of Science Wuhan University of Technology Wuhan 430070 China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution

The Role of Calcium in Microstructural Refinement of AZ91.Magnesium Alloy

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Journal of wuhan {1. of {2.(Materials science) 2006年第4期21卷 45-47页

作者：刘生发 School of Materials science and Engineering Wuhan University of Technology Wuhan 430070China

The effect of calcium addition on the microstructures of AZ91.magnesium alloy was investigated. It was found that a small amount of calcium in AZ91.allay produced a large decrease in the α- Mg grain size and the dispersed fine β-Mgt7 Alt2.phases. In addition, some Al4Ca particles were found to exist in the AZ91.alloy containing 0.5wt% Ca. EDS analysis and water-quenched technique revealed that the grain-refining mechanism of calcium for the AZ91.alloys was mainly attributed to the role of restricting growth of calcium in the primary α-Mg crystals.

关键词： AZ91.magnesium alloy calcium microstructural refinement

A Microenvironment, Rather than Chemical, Initiates the Cardiomyogenic Differentiation of Marrow Stromal Cells

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wuhan {1. Journal of Natural {2.s 2004年第4期9卷 513-521页

作者： LIU Wei-xin 1.2., SONG Jian 1. , WAN Yu 1. PAN Guo-dong 1., LIU Yu 1., CHENG Bang-chang 2.,CHEN Xi-chang 1.1. School of Medicine, wuhan {1., wuhan 430071. hubei,{12. 2. Renmin Hospital, wuhan {1., wuhan 430060, hubei,{12. wuhan {1. School of Medicine Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. Renmin Hospital Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. School of Medicine Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. Renmin Hospital Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

To investigate the potential of cardiomyogenic differentiation of rat bone marrow stromal cells (MSCs), they were exposed to 5-azacytidine tretments (single/repeat) at varying concentrations (3, 5, 1. μmol/L) and the fates of the cells were analyzed by immunocytochemistry, Western blot and the reporter gene of enhanced cyan fluorescent protein (ECFP) under the control of ventricular myosin light chain 2.(MLC2.) promoter. MSCs were also cocultured with cardiomyocytes for periods up to 1. days, the expression of cardiac myosin heavy chain (MHC) and troponin I (Tn I) proteins was analyzed. After the induction with 5-azacytidine, neither spontaneously bea{2. cells nor myotubes were found; MHC and Tn I proteins were also undetectable and no ECFP-positive MSCs were detected. But when cocultured with cardiomyocytes, spontaneously contrac{2. MSCs were observed and cardiac specific proteins could be detected. The results proved that the novel effects of 5-azacytidine on the cardiomyogenic differentiation of MSCs should be questioned and a direct intercellular communication with cardiomyocytes is necessary for MSCs to differentiate into cardiomyocytes. Key words cardiomyocyte - cell differentiation - stem cell CLC number Q 81..5 - R 542.2.2.Foundation item: Supported by the Natural {2. Foundation of hubei Province (2.02.B001.0)Biography: LIU Wei-xin (1.76-), male, Ph. D candidate, research direction: stem cell and cellular biology.

关键词： cardiomyocyte cell differentiation stem cell