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Effect of solution concentration on the structured order and optical properties of short-chain polyene biomolecules

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Science China(physics,Mechanics & Astronomy) 2010年第9期53卷 1646-1650页

作者： OUYANG ShunLi1,2,SUN ChengLin1,2,ZHOU Mi1,2,LI DongFei2,WANG WeiWei1,2,QU GuanNan1,LI ZuoWei1,2,GAO ShuQin1 & YANG JianGe3.1 State Key Laboratory of Superhard Materials,Jilin University,Changchun 13.012,China 2 College of physics,Jilin University,Changchun 13.023.China 3.The ordnance Engineering department,Air Force Aviation University,Changchun 13.022,China 1. State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China2. College of Physics Jilin University Changchun 130023 China3. The ordnance Engineering Department Air Force Aviation University Changchun 130022 China

We have measured the Raman spectra and UV-Vis absorption spectra of linear polyene biomolecules(β-carotene and lycopene) in CS2 at low concentrations(10-6-10-10 mol/L).With decreasing concentration,all the carbon-carbon vibrations form a coherent mode in ordered β-carotene and lycopene due to extended π-conjugation that gives strong electron-phonon coupling,which leads to an anomalous experimental *** observed an extremely high Raman scattering cross section(RSCS) and the Raman activities in β-carotene and lycopene are characterized by intensive overtones and ***,the UV-Vis absorption bands become narrower.

关键词： molecular structured order Raman spectroscopy Raman scattering cross section

Effect of Spontaneous Emission on Both Atomic Dynamics and Momentum Transfer of an Atomcavity System

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Chinese Journal of Lasers 1999年第4期8卷 3-5页

作者： YI Xuexi 1 WANG Haijun 2 BA Xinwu 2 WANG Jianwei 3. ( 1 Institute of Theoretical physics, Northeast Normal University, Changchun 13.024, China 2 department of Chemistry, Hebei University, Baoding 071000, China 3.department of 东北师范大学理论物理所吉林长春 130024 河北大学化学系河北保定 071000 河北大学化学系河北保定喀什师范学院物理系新疆喀什 844000

The dynamics of an atom coupling to a quantized cavity field have been studied. The atom is treated as a two level system with a spontaneous emission rate. The transition probabilities have been given for both adiabatic and non adiabatic situations. For a special Λ type atom with dark state, the problem of momentum transfer is discussed in details. The influence of spontaneous emission on validity of the adiabatic approximation is also discussed.

关键词： atomic dynamic momentum transfor quantized cavity

Nuclear Effect on Gluon Distribution Function and Associate Production of J/Ψ and y with Large P_T in High Energy p-Fe Collision

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Chinese journal of nuclear physics 1995年第3期17卷 205-208页

作者： Zhang Shu~2 He Zhe-min~(1,2) Peng Hong-an~(1,3. Duan Chun-gui~21 CCAST(World Laboratory)P.O.Box 873.,Biejing 1000802 physics department,Hebei Normal University,Shijiazhuang,0500163.physics department,Peking University,Beijing 100871 Hebei Normal Univ Shijiazhuang China

With three theoretical models of nuclear effects on gluon distribution functions,the differentialcross sections and the total cross sections for associate production of J/ψ and γ with large P_T in high energyp-Fe co... 详细信息

关键词： Gluon distribution function Nuclear effect J/Ψ production

Formation of bulk ferromagnetic nanostructured Fe_(40)Ni_(40)P_(14)B_6 alloys by metastable liquid spinodal decomposition

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Science China(Technological Sciences) 2009年第7期52卷 1919-1922页

作者： LI Qiang1,2 1 School of physics Science and Technology, Xinjiang University, Urumqi 83.046, China 2 department of physics, The Chinese University of HongKong, Shatin N.T., HongKong, China School of physics Science and Technology Xinjiang University Urumqi 830046 China department of physics The Chinese University of HongKong Shatin N.T. HongKong China

Nanostructured Fe40Ni40P14B6 alloy ingots of 3.5 mm in diameter could be synthesized by a metastable liquid state spinodal decomposition method. For undercooling T> 260 K, the microstructure of the undercooled specimen had exhibited liquid state spinodal decomposition in the undercooled liquid state. The microstructure could be described as two intertwining networks with small grains dispersed in them. For undercooling T>290 K, the overall microstructure of the specimen changed into a granular morphology. The average grain sizes of the small and large grains are 3. nm and 80 nm, respectively. These prepared samples are soft magnets with saturation magnetization Bs 0.744 T.

关键词： nanomaterials magnetic materials solidification bulk nanostructured alloy Fe40Ni40P14B6 metastable liquid spinodal decomposition

Some invariant properties of ordered information systems under homomorphism

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Science China(Information Sciences) 2010年第9期53卷 1816-1825页

作者： WANG ChangZhong1*,CHEN DeGang2 & HU QingHua3.1department of Mathematics,Bohai University,Jinzhou 121000,China 2department of Mathematics and physics,North China Electric Power University,Beijing 102206,China 3.ower Engineering,Harbin Institute of Technology,Harbin 150001,China 1. department of Mathematics Bohai University Jinzhou 121000 China2. Department of Mathematics and Physics North China Electric Power University Beijing 102206 China3. Power Engineering Harbin Institute of Technology Harbin 150001 China

In this paper,some properties of ordered information systems under homomorphism are *** concept of a consistent function with respect to dominance relations is first introduced and its properties are ***,some main invariant properties of dominance relations under relation mappings are *** is proven that attribute reductions in the original ordered information system and its image system are equivalent under the condition of *** means of the results,we can get the smaller image system that has the same reducts as a given massive ordered information system.

关键词： consistent function dominance relation ordered information system homomorphism reduction

Noether-type theory for discrete mechanico-electrical dynamical systems with nonregular lattices

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Science China(physics,Mechanics & Astronomy) 2010年第9期53卷 1687-1698页

作者： FU JingLi1,CHEN LiQun2 & CHEN BenYong3.1 Institute of Mathematical physics,Zhejiang Sci-Tech University,Hangzhou 3.0018,China 2 department of Mechanics,Shanghai University,Shanghai 200072,China 3.Faculty of Mechanical-Engineering & Automation,Zhejiang Sci-Tech University,Hangzhou 3.0018,China 1. Institute of Mathematical physics Zhejiang Sci-Tech University Hangzhou 310018 China2. Department of Mechanics Shanghai University Shanghai 200072 China3. Faculty of Mechanical-Engineering & Automation Zhejiang Sci-Tech University Hangzhou 310018 China

We investigate Noether symmetries and conservation laws of the discrete mechanico-electrical systems with nonregular *** operators of discrete transformation and discrete differentiation to the right and left are introduced for the *** on the invariance of discrete Hamilton action on nonregular lattices of the systems with the dissipation forces under the infinitesimal transformations with respect to the time,generalized coordinates and generalized charge quantities,we work out the discrete analog of the generalized variational *** this formula we derive the discrete analog of generalized Noether-type identity,and then we present the generalized quasi-extremal equations and properties of these equations for the *** also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the *** we use an example to illustrate these results.

关键词： Noether symmetry variational formula quasi-extremal equation conservation law discrete mechanico-electrical dynamical system

Ground state properties of La isotopes in reflection asymmetric relativistic mean field theory

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Science China(physics,Mechanics & Astronomy) 2009年第10期52卷 1574-1578页

作者： WANG Nan1 & GUO Lu2 1 College of physics,Shenzhen University,Shenzhen 518060,China 2 department of physics,Faculty of Science,University of Tokyo,Tokyo 113.003.,Japan College of physics Shenzhen University Shenzhen 518060 China department of physics Faculty of Science University of Tokyo Tokyo 113-0033 Japan

The ground state properties of La isotopes are investigated with the reflection asymmetric relativistic mean field(RAS-RMF) *** calculation results of binding energies and the quadrupole moments are in good agreements with the *** calculation results indicate the change of the quadrupole deformation with the nuclear mass *** "kink" on the isotope shifts is observed at A = 13. where the neutron number is the magic number N = *** is also found that the octupole deformations may exist in the La isotopes with mass number A ～ 145-155.

关键词： reflection asymmetric relativistic mean field(RAS-RMF) theory nuclear deformation binding energy

Symmetries and exact solutions of discrete nonconservative systems

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Science China(physics,Mechanics & Astronomy) 2010年第9期53卷 1699-1706页

作者： FU JingLi1,LI XiaoWei2,LI ChaoRong1,ZHAO WeiJia3.& CHEN BenYong4 1 Institute of Mathematical physics,Zhejiang Sci-Tech University,Hangzhou 3.0018,China 2 department of physics,Shangqiu Normal University,Shangqiu 476000,China 3.department of Mathematics,Qingdao University,Qingdao 266071,China 4 Faculty of Mechanical Engineering & Automation,Zhejiang Sci-Tech University,Hangzhou 3.0018,China 1. Institute of Mathematical physics Zhejiang Sci-Tech University Hangzhou 310018 China2. Department of Physics Shangqiu Normal University Shangqiu 476000 China3. Department of Mathematics Qingdao University Qingdao 266071 China4. Faculty of Mechanical Engineering & Automation Zhejiang Sci-Tech University Hangzhou 310018 China

Based on the property of the discrete model entirely inheriting the symmetry of the continuous system,we present a method to construct exact solutions with continuous groups of transformations in discrete nonconservative *** Noether's identity of the discrete nonconservative system is *** symmetric discrete Lagrangian and symmetric discrete nonconservative forces are defined for the *** quasi-extremal equations of discrete nonconservative systems are *** conserved quantities are derived with symmetries associated with the continuous *** have also found that the existence of the one-parameter symmetry group provides a reduction to a conserved quantity;but the existence of a two-parameter symmetry group makes it possible to obtain an exact solution for a discrete nonconservative *** examples are discussed to illustrate these results.

关键词： discrete nonconservative system symmetry conserved quantity quasi-extremal equation exact solution

Fracture Mechanics,Crack Propagation and Microhardness Studies on Flux Grown ErAlO_3.Single Crystals

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Journal of Materials Science & Technology 2000年第4期16卷 405-410页

作者： K.K.Bamzai and P.N.Kotru (department of physics, University of Jammu, Jammu 180006, India) B.M Wanklyn (department of physics, Clarendon Laboratory, Oxford University, Oxford OX1 3.U, U.K.) department of physics University of Jammu Jammu 180006 India department of physics Clarendon Laboratory Oxford University Oxford OX1 3PU United Kingdom

Results on fracture mechanics and crack propagation have been obtained, making use of Vickers microhardness studies on two different crystallographic planes [(110) and (001)] of flux grown erbium aluminate crystals in the load ranging from 10-100 g. The variation of microhardness with load which is best explained by Hays and Kendall's law leads to the load independent values of hardness. Classification of cracks is dealt with and it is reported that the transition from Palmqvist to median types of cracks occurs at higher loads. The values of fracture toughness (K_C), and brittleness index (B_i) are calculated using median types of cracks.

关键词： Fracture Mechanics Crack Propagation and Microhardness Studies on Flux Grown ErAlO3.Single Crystals