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A Study on Dynamic Response of Cable-Seabed Interaction

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Journal of Shanghai Jiaotong university(Science) 2009年第4期14卷 443-449页

作者：王飞黄国樑邓德衡涂兴华 Merchant Marine College Shanghai Maritime University State Key Laboratory of Ocean Engineering Shanghai Jiaotong University

A numerical method is developed to investigate the dynamic response of cable-seabed interaction in this paper. The motion of cable is described by the Lumped Parameter Method, while the seabed, unlike the prevailing simplified model of elastic foundation, is modeled as an irregular continuous rigid surface with rebound and friction existing, and the forces exerted by the seabed consist of normal counterforce and isotropic tangential Coulomb friction resistance. To describe the detailed dynamic response, two coefficients are introduced by analogy with the theory of rigid body collision with friction. The cable-seabed kinematic and dynamic contact conditions are formulated subsequently, and are used to incorporate the seabed effect into the cable dynamics to produce a set of ordinary differential governing equations. In this paper, we employ 4th order Runge-Kutta method to solve these equations. Several simulation cases are presented to illustrate the seabed effect. The results show that friction and impact have a prominent influence on the statics and dynamics of the cable.

关键词： towed cable numerical simulation seabed interaction impact with friction

Dynamical Behavior of Core ^3He Nuclear Reaction-Diffusion Systems and Sun＇s Gravitational Field

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Transactions of Tianjin University 2005年第1期11卷 30-34页

作者：杜九林申洪 School of Sciences Tianjin University Tianjin 300072 China Department of physics Gannan Teachers College Ganzhou 330047 China

The coupling of the sun's gravitational field with processes of diffusion and convection exerts a significant influence on the dynamical behavior of the core 3He nuclear reaction-diffusion system. Stability analyses of the system are made in this paper by using the theory of nonequilibrium dynamics. It is showed that, in the nuclear reaction regions extending from the center to about 0.38 times of the radius of the sun, the gravitational field enables the core 3He nuclear reaction-diffusion system to become unstable and, after the instability, new states to appear in the system have characteristic of time oscillation. This may change the production rates of both 7Be and 8B neutrinos.

关键词： stellar nuclear reaction solar neutrino problem astrophysical hydrodynamics

Further research on high-spin structure in ^(1.1.Lu

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Science china({1.,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1.2.YU ShaoYing1.2.4,SHEN CaiWan1.5,LI XiaoWei6 & CHEN YongShou3,4 1.School of Science,Huzhou teachers College,Huzhou 31.000,china 2.College of Mathematics,{2. and Information Engineering,Zhejiang Normal University,Jinhua 32.000,china 3 china Institute of Atomic Energy,Beijing 1.2.1.,china 4 Institute of Theoretical {2.,Chinese Academy of Sciences,Beijing 1.0080,china 5 Center of Theoretical Nuclear {2.,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china 6 Department of {2.,Chifeng University,Chifeng 02.001.china School of Science Huzhou Teachers College Huzhou 313000 China College of Mathematics Physics Information Engineering Zhejiang Normal University Jinhua 321000 China china Institute of Atomic Energy Beijing 102413 China Institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China Department of physics Chifeng University Chifeng 024001 China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2.in 1.1.u. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i1./2.also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

Microstructure evolution of single crystal copper wires in cold drawing

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Science china(Technological Sciences) 2007年第6期50卷 736-748页

作者： CHEN Jian1.2. YAN Wen1.2. WANG XueYan2.& FAN XinHui2.1.Department of Applied physics, Northwestern Polytechnical University, Xi’an 71.072. china 2.School of Material Science and Chemical Engineering, Xi’an Technological University, Xi’an 71.032. china 1. Department of Applied physics Northwestern Polytechnical University Xi’an 710072 China 2. School of Material Science and Chemical Engineering Xi’an Technological University Xi’an 710032 China

The deformation microstructure evolution of single crystal copper wires produced by OCC method has been studied with the help of TEM, EBSD; OM. The results show that there are a small number of dendrites; twins in the undeformed single crystal copper wires. However, it is difficult to observe these dendrites in deformed single crystal copper wires. The structure evolution of deformed single crystal copper wires during drawing process can be divided into three stages. When the true strain is lower than 0.94, macroscopic subdivision of grains is not evident,; the microscopic evolution of deformed structure is that the cells are formed; elongated in drawn direction. When the true strain is between 0.94; 1.96, macroscopic subdivision of grains takes place,; the number of microbands located on {111}; cell blocks is much more than that with the true strain lower than 0.94. When the true strain is larger than 1.96, the macroscopic subdivision of grains becomes more evident than that with the true strain between 0.94; 1.96,; S-bands structure; lamellar boundaries will be formed. From EBSD analysis, it is found that part of 100 texture resulting from solidifying is transformed into 111; 112.due to shear deformation, but 100 texture component is still kept in majority. When the true strain is 0.94, the misorientation angle of dislocation boundaries resulting from deformation is lower than 14°. However, when the true strain arrives at 1.96, the misorientation angle of some boundaries will be greater than 50°,; the peak of misorientation angle distribution produced by texture evolution is located in the range between 2.°; 30°.

关键词： single crystal copper wires, deformation structure, electron backscattering diffraction, transmission electron microscopy

Constructing super Gabor frames:the rational time-frequency lattice case

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Science china Mathematics 2010年第12期53卷 3179-3186页

作者： LI ZhongYan 1.& HAN DeGuang 2. 1.Department of Mathematics and {1., North china Electric Power University, Beijing 1.2.06, china 2.Department of Mathematics, University of Central Florida, Orlando, FL 32.1., USA 1. Department of Mathematics and physics North China Electric Power University Beijing 102206 China2. Department of Mathematics University of Central Florida Orlando FL 32816 USA

For a time-frequency lattice Λ = A Z d × B Z d , it is known that an orthonormal super Gabor frame of length L exists with respect to this lattice if and only if |det( AB) | = 1.L . The proof of this result involves various techniques from multi-lattice tiling and operator algebra theory, and it is far from constructive. In this paper we present a very general scheme for constructing super Gabor frames for the rational lattice case. Our method is based on partitioning an arbitrary fundamental domain of the lattice in the frequency domain such that each subset in the partition tiles R d by the lattice in the time domain. This approach not only provides us a simple algorithm of constructing various kinds of orthonormal super Gabor frames with flexible length and multiplicity, but also allows us to construct super Gabor (non-Riesz) frames with high order smoothness and regularity. Several examples are also presented.

关键词： super Gabor frame orthonormal super frame full rank lattice tiles

An unconstrained optimization method using nonmonotone second order Goldstein's line search

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Science china Mathematics 2007年第10期50卷 1389-1400页

作者： Wen-yu SUN~(1.) Qun-yan ZHOU~(1.2. ~1.School of Mathematics and Computer Science,Nanjing Normal University,Nanjing 2.0097,china ~2.Department of Basic Courses,Jiangsu teachers University of Technology,Changzhou 2.3001.china 1. School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China 2. Department of Basic Courses Jiangsu Teachers University of Technology Changzhou 213001 China

In this paper, an unconstrained optimization method using the nonmonotone second order Goldstein's line search is proposed. By using the negative curvature information from the Hessian,the sequence generated is shown to converge to a stationary point with the second order optimality conditions. Numerical tests on a set of standard test problems confirm the efficiency of our new method.

关键词： nonmonotone method, direction of negative curvature, line search, descent pair,unconstrained optimization

Controlled synthesis and magnetic properties of Fe_3O_4 walnut spherical particles and octahedral microcrystals

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Science china(Technological Sciences) 2008年第11期51卷 1911-1920页

作者： JIAO Hua1.2.& YANG HeQing1.1.Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, Xi’an 71.062. china 2.Department of Chemistry and Chemical Engineering, Weinan teachers University, Wei nan 71.000, china Key Laboratory of Macromolecular Science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi’an 710062 China Department of Chemistry and Chemical Engineering Weinan Teachers University Wei nan 714000 China

Magnetite Fe3O4 walnut spherical particles and octahedral microcrystals were suc- cessfully synthesized from K4 [Fe (CN) 6], K3 [Fe (CN) 6] and NaOH reagents via a simple hydrothermal process. And the uniform morphology of octahedral micro- crystals was obtained in the presence of ethylene glycol. The morphology and structure of products were characterized by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the Fe3O4 walnut spherical particles and octahedral microcrystals were single crystals with the face-center cubic structure and with size distributions from 2.2.to 8.6 μm and 1.6 to 1.0}5 μm, respectively. Their magnetic properties were detected by a vibrating sample magnetometer at room temperature. The walnut spherical parti- cles exhibited a ferromagnetic behavior with the coercive force (Hc), saturation magnetization (Ms) and remanent magnetization (Mr) being 1.0.57 Oe, 97.634 and 1.0}05 emu/g, respectively. For the octahedral microcrystals they were 75.2. Oe, 1.1.90 and 6.69 emu/g, respectively. Different sizes of walnut spherical particles were controlled synthesized through adjusting the NaOH concentration. It was found that ethylene glycol molecules have a significant effect on the formation of Fe3O4 octahedra. A possible mechanism was also proposed to account for the growth of these Fe3O4 products

关键词： a hydrothermal route Fe3O4 walnut spherical particles octahedral microcrystals magnetic property

新型超导材料MgCNi_3的电子结构与超导电性研究

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物理学报 2004年第3期53卷 922-926页

作者：陈丽李华山东大学物理与微电子学院

用MS Xα方法研究了非氧化物超导材料MgCNi3的电子结构 .研究结果显示 ,态密度分布曲线的主峰靠近Fermi面 ,主要来自于Ni的d电子的贡献 .用T(T =Co ,Mn ,Cu)替代MgCNi3中的部分Ni形成化合物MgCNi2.T ,替代使Ni的价电子数减小 ,价态发生... 详细信息

用MS Xα方法研究了非氧化物超导材料MgCNi3的电子结构 .研究结果显示 ,态密度分布曲线的主峰靠近Fermi面 ,主要来自于Ni的d电子的贡献 .用T(T =Co ,Mn ,Cu)替代MgCNi3中的部分Ni形成化合物MgCNi2.T ,替代使Ni的价电子数减小 ,价态发生变化 ,Fermi面处态密度N(EF)减小 .计算结果表明 :无论是电子掺杂 (Cu)还是空穴掺杂 (Co ,Mn) ,MgCNi3的超导电性都被抑制 ;Mn掺杂比Co掺杂更快地抑制超导电性。

关键词：超导材料电子结构态密度超导电性镍碳镁材料 Fermi面电子掺杂空穴掺杂

Calculation of triaxial superdeformation in ^(1.4)Hf

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Science china({1.,Mechanics & Astronomy) 2007年第5期50卷 553-557页

作者： YU ShaoYing1.2.4, LI XiaoWei2. SHEN CaiWan1.5 & CHEN YongShou3,4 1.School of Science, Huzhou teachers College, Huzhou 31.000, china 2.College of Mathematics, {2. and Information Engineering, Zhejiang Normal University, Jinhua 32.000, china 3 china Institute of Atomic Energy, Beijing 1.2.1., china 4 Institute of Theoretical {2., Chinese Academy of Sciences, Beijing 1.0080, china 5 Center of Theoretical Nuclear {2., National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, china 1. School of Science Huzhou Teachers College Huzhou 313000 China 2. College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321000 China 4. Institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China 5. Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China 3. china Institute of Atomic Energy Beijing 102413 China

A two-dimensional Total Routhian Surface (TRS) calculation with the fixed hexa- decapole deformation ε4 = 0.03 was carried out for several configurations of 1.4Hf. Results indicate that the shell corrections have an important contribution to the formation of triaxial superdeformation in 1.4Hf and some possible configuration assignments are made to the 4 TSD bands experimentally found in 1.4Hf.

关键词： Total Routhian Surface (TRS), triaxial superdeformation, configuration