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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 XianBao1,3 1 College of Science, china Three Gorges university, Yichang 443002, china 2 school of physics and technology, wuhan university, wuhan 430072, china 3 Institute of Particle physics, Central china Normal university, wuhan 430070, china 1. College of Science China Three Gorges University Yichang 443002 China 2. school 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

Application of PowerBuilder User Objects in Developing Distributed Programs

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wuhan university Journal of Natural Sciences 2001年第4期6卷 822-825页

作者： Wang Li\|fu 1, Li Hua\|ming 2 1. Human Source Department, wuhan Telecom Industry Group Co. Ltd., wuhan 430074, china 2.school of physics and technology, wuhan university,wuhan 430072,china wuhan Telecom Industry Group Co. Ltd. Human Source Department Wuhan China wuhan university School of Physics and Technology Wuhan China (GRID:grid.49470.3e) (ISNI:***)

User Objects are the basement in developing distributed PowerBuilder applications. There are two kinds of PowerBuilder objects: visual objects and non-visual objects. Usually we use non-visual objects to perform the PowerBuilder distriuted application. This paper introduces the method of developing PowerBuilder distributed application program, mainly discusses the application of nonvisual objects when developing PowerBuilder distributed application programs.

关键词： Key words PowerBuilder user object shared object remote object server push

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催化热解C_2H_2制备螺旋形碳晶须

武汉大学学报（理学版） 2004年第5期50卷 559-562页

作者：郭定和范湘军湖北大学物理与电子技术学院湖北武汉430062 武汉大学物理科学与技术学院湖北武汉430072

以Ni粉为催化剂,在高温下催化热解乙炔(C2H2),制备出了螺旋形碳晶须材料.实验结果表明:催化热解乙炔(C2H2)制备螺旋形碳晶须的最佳温度范围为450～600℃,恒温时间为60～70min,气体流量比分别为ρ(C2H2)∶ρ(Ar)=7∶6,ρ(C2H2)∶ρ(Ar)=2... 详细信息

以Ni粉为催化剂,在高温下催化热解乙炔(C2H2),制备出了螺旋形碳晶须材料.实验结果表明:催化热解乙炔(C2H2)制备螺旋形碳晶须的最佳温度范围为450～600℃,恒温时间为60～70min,气体流量比分别为ρ(C2H2)∶ρ(Ar)=7∶6,ρ(C2H2)∶ρ(Ar)=25∶3及ρ(C2H2)∶ρ(Ar)∶ρ(H2)=3∶4∶7.经透射电镜、扫描电镜、X射线衍射仪分析表明,螺旋形碳晶须的螺径为130～1000nm,螺距为100～350nm,晶须直径在100nm左右,晶须长度达几百微米.在加入氢气的情况下,出现了少量的直径在500nm左右的管状碳晶须.将螺旋形碳晶须放入Ar气中,850℃温度下经历1h,成分结构未变,结晶性更好.

关键词：催化热解晶体生长制备螺旋形碳晶须乙炔气体流量

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聚乙炔的CH面外振动红外光谱研究

武汉大学学报（理学版） 2002年第5期48卷 601-603页

作者：任大志张卫王军武汉大学期刊社湖北武汉430072 武汉大学物理科学与技术学院湖北武汉430072

采用从头计算方法 ,计算了反式和顺式聚乙炔的氢原子在垂直于聚乙炔分子面方向振动的红外光谱计算表明 ,Gibson等用红外吸收实验所测得的谱线的确是聚乙炔的CH面外振动产生的谱线经 10 0℃长时间加热后 ,顺式聚乙炔变为反式聚炔 ,... 详细信息

采用从头计算方法 ,计算了反式和顺式聚乙炔的氢原子在垂直于聚乙炔分子面方向振动的红外光谱计算表明 ,Gibson等用红外吸收实验所测得的谱线的确是聚乙炔的CH面外振动产生的谱线经 10 0℃长时间加热后 ,顺式聚乙炔变为反式聚炔 ,但波数为 74 0cm- 1 的谱线仍保留 5

关键词： CH面外振动聚乙炔派尔斯相变红外光谱从头计算顺式结构反式结构

A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU school of Economics and Management,wuhan university,wuhan 430072,china school of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

A Multi-Soliton Solution of the DNLS Equation Based on Pure Marchenko Formalism

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wuhan university Journal of Natural Sciences 2010年第1期15卷 36-42页

作者： ZHOU Guoquan school of physics and technology,wuhan university,wuhan 430072,Hubei,china school of physics and technology Wuhan University Wuhan China

By means of some algebraic techniques,especially the Binet-Cauchy formula,an explicit multi-soliton solution of the derivative nonlinear Schrdinger equation with vanishing boundary condition is attained based on a pure Marchenko formalism without needing the usual scattering data except for given N simple poles. The one-and two-soliton solutions are given as two special examples in illustration of the general formula of multi-soliton solution. Their effectiveness and equivalence to other approaches are also demonstrated. Meanwhile,the asymptotic behavior of the multi-soliton solution is discussed in detail. It is shown that the N-soliton solution can be viewed as a summation of N one-soliton solutions with a definite displacement and phase shift of each soliton in the whole process(from t →∞ to t → +∞ ) of the elastic collisions.

关键词： soliton derivative nonlinear Schrdinger (DNLS) equation nonlinear equation Marchenko equation

Ferroelectric properties of Bi_(3.4)Ho_(0.6)Ti_3O_(12) thin films prepared by sol-gel method

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Science china(Technological Sciences) 2008年第9期51卷 1439-1444页

作者： FU ChengJu1, HUANG ZhiXiong1, LI Jie2 & GUO DongYun3 1 school of Materials Science and technology, wuhan university of technology, wuhan 430070, china 2 school of Mechanical Engineering, Chongqing university of Science and technology, Chongqing 400050, china 3 Department of physics, wuhan university, wuhan 430072, china school of Materials Science and technology Wuhan University of Technology Wuhan 430070 China school of Mechanical Engineering Chongqing University of Science and Technology Chongqing 400050 China Department of physics Wuhan University Wuhan 430072 China

We have prepared the Ho-substituted bismuth titanate (Bi3.4Ho0.6Ti3O12, BHT) thin films on Pt/Ti/SiO2/Si substrates using sol-gel method. The crystal structure and morphology of the films were characterized using X-ray diffraction and atomic force microscopy. The BHT film shows a single phase of Bi-layered Aurivillius structure and dense microstructure. The 2Pr and 2Ec of the 600-nm-thick BHT film were 38.4 μC/cm2 and 376.1 kV/cm, respectively at applied electric field 500 kV/cm. The dielectric constant and dielectric loss are about 310 and 0.015 at a frequency of 1 MHz, respectively. The Pr value decreased to 93% of its pre-fatigue values after 4.46×109 switching cycles at 1 MHz frenquency, and the BHT film shows good in-sulating behavior according to the test of leakage current.

关键词： Bi3.4Ho0.6Ti3O12 thin film sol-gel method ferroelectric property fatigue dielectric constant

Nonlinear Refractive Index and Absorption Coefficient of Single-Shell Semiconductor Carbon Nanotube

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wuhan university Journal of Natural Sciences 2003年第3A期8卷 833-836页

作者： Lu Ni,Xiong Gui\|guang  school of physics and technology, wuhan university, wuhan 430072, Hubei, china wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The nonlinear refractive index and absorption coefficient of single\|shell semiconductor carbon nanotubes(CN s ) are calculated based on the two\|band approximation and Genkin\|Mednis approach. The results of nonlinear refractive index and absorption coefficient reach the order of 10 -8 and 10 -4 cm 2\5W -1 separately, which indicates that CN s have wonderful nonlinear optical properties. Taking into account the temperature effect and overlapping of σ and π orbits, the effect of relaxation term and chiral angle is discussed. The results show that the smaller the relaxation term, the larger the nonlinear absorption coefficient and refractive index. At the same time, CN s with different chiral angles have different results due to their different energy gap.

关键词： nonlinear refractive index nonlinear absorption coefficient relaxation chiral angle

Weak martingale Hardy spaces and weak atomic decompositions

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Science china Mathematics 2006年第7期49卷 912-921页

作者： HOU Youliang & REN Yanbo school of Mathematics and Statistics, wuhan university, wuhan 430072, china Department of Mathematics & physics, Henan university of Science and technology, Luoyang 471003, china 1. school of Mathematics and Statistics Wuhan University Wuhan 430072 China 2. Department of Mathematics & physics Henan University of Science and Technology Luoyang 471003 China

In this paper we define some weak martingale Hardy spaces and three kinds of weak atoms. They are the counterparts of martingale Hardy spaces and atoms in the classical martingale Hp-theory. And then three atomic decomposition theorems for martingales in weak martingale Hardy spaces are proved. With the help of the weak atomic decompositions of martingale, a sufficient condition for a sublinear operator defined on the weak martingale Hardy spaces to be bounded is given. Using the sufficient condition, we obtain a series of martingale inequalities with respect to the weak Lp-norm, the inequalities of weak (p ,p)-type and some continuous imbedding relationships between various weak martingale Hardy spaces. These inequalities are the weak versions of the basic inequalities in the classical martingale Hp-theory.

关键词： martingale, weak Hardy space, weak atom, atomic decomposition.