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Effect of Cooling Rate on the Microstructure of ZA48 Alloy

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Journal of Wuhan University of Technology(materials Science) 2010年第5期25卷 811-813页

作者：王杰芳谢敬佩 School of physics and Engineering The Key Laboratory of Material Physics of the Ministry of Education of China Zhengzhou University The College of materials Science & Engineering Henan University of Science and Technology

The effect of cooling rate on the microstructure of ZA48 alloy was investigated. The alloy was prepared using a relatively simple technique, i e, rapid cooling of the melt in a steel wedge mould. The dependence of microstructure on the cooling rate （about 40 to 10^3 K/s） was determined by the secondary dendrite arm space size measurement, optical microscopy（OM）, and transmission electron microscopy （TEM）. It is found that the matrix structure over a large cooling rate is composed of α-Al dendrite and eutectoid （α＋η）, the size of α-Al dendrite decreases with increasing cooling rate. The relationship between the cooling rate and the secondary dendrite arm space size has been established. TEM shows that a large number of small and dispersed precipitations can be seen in the primary α phase of tip region. Electron diffraction pattern shows that the precipitate phase is Zn3Mg2.phase.

关键词： cooling rate microstructure secondary dendrite arm space size precipitation

Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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Science china(physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2.1. key laboratory of Beam Technology and {2. Modification of ministry of education, Beijing Normal University, Beijing 100875, china 2. physics Department, Beijing Normal University, Beijing 100875, china 3. china Institute of Atomic Energy, Beijing 102.13, china key laboratory of Beam Technology material Modification of ministry of education Beijing Normal University Beijing 100875 China physics Department Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(30Si,4n)2.0Hs, 2.8U(36S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(36S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Refraction of light in media

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 591-600页

作者： ZHANG Tao key laboratory of Beam Technology and {2. Modification of ministry of education, Institute of Low Energy Nuclear physics, Beijing Normal University, Beijing 100875, china Beijing Radiation Center, Beijing 100875, china key laboratory of Beam Technology material Modification of ministry of education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China

The roles of the magnetic field and electric field of the light are investigated when the light is refracted in the medium. The model of the electron cloud conductor is presented. Electron cloud in a molecule is treated as a conductor and the Faraday’s Law is applied to this conductor that is in the alternating magnetic field of the light. dBM/dt of the light gives rise to an alternating induced current on the electron cloud conductor, and the light exchanges energy, i.e. the refractive energy, with the elec- tron cloud conductor. Formulas of refractive index, which is the ratio of light speed in vacuum to that in the medium, are derived with this model. These formulas are tested with several mediums and Langevin’s diamagnetic susceptibility of helium gas, and the results are in good agreement with the measured data. The anisotropy and the nonlinearity of the refractive index are explained with the theory described in this work.

关键词： refractive index, light, speed, medium, propagation

First-principles calculations on implanted TiO_2.by 3d transition metal ions

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 838-842页

作者： HOU XingGang1,2. HUANG MeiDong1, WU XiaoLing2.& LIU AnDong2.1 Department of physics, Tianjin Normal University, Tianjin 300387, china 2.{2. laboratory of Beam Technology and material Modification of ministry of education, Beijing Normal University, Beijing 100875, china Department of physics Tianjin Normal University Tianjin 300387 China key laboratory of Beam Technology and {2. Modification of ministry of education Beijing Normal University Beijing 100875 China

3d transition metal (V, Cr and Fe) ions are implanted into TiO2.by the method of metal ion implantation. The electronic band structures of TiO2.films doped 3d transition metal ions have been analyzed by ab initio band calculations based on a self-consistent full-potential linearized augmented plane-wave method within the first-principle formalism. Influence of implantation on TiO2.films is examined by the method of UV-visible spectrometry. The results of experiment and calculation show that the optical band gap of TiO2.films is narrowed by ion implantation. The calculation shows that the 3d state of V, Cr and Fe ions plays a significant role in red shift of UV-Vis absorbance spectrum.

关键词： 3d transition metal ions implantation TiO2 FP-LAPW electronic structure

Two-dimensional thermoelasticity solution for functionally graded thick beams

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 451-460页

作者： Lü Chaofeng1, CHEN Weiqiu1 & ZHONG Zheng2.1. Department of Civil Engineering, Zhejiang University, Hangzhou 31002., china 2. key {2. of Solid Mechanics of ministry of education, School of Aerospace Engineering and Ap- plied Mechanics, Tongji University, Shanghai 2.0092. china Department of Civil Engineering Zhejiang University Hangzhou 310027 China key laboratory of Solid Mechanics of{2. School of Aerospace Engineering Applied Mechanics Tongji University Shanghai 200092 China

Two-dimensional thermoelasticity analysis of functionally graded thick beams is presented using the state space method coupled with the technique of differential quadrature. material properties vary continuously and smoothly through the beam thickness, leading to variable coefficients in the state equation derived from the elasticity equations. Approximate laminate model is employed to translate the state equation into the one with constant coefficients in each layer. To avoid numerical instability, joint coupling matrices are introduced according to the continuity conditions at interfaces in the approximate model. The differential quadrature procedure is applied to discretizing the beam in the axial direction to make easy the treatment of arbitrary end conditions. A simply-supported beam with exponentially varying material properties is considered to validate the present method. Numerical examples are performed to investigate the influences of relative parameters.

关键词： state equation differential quadrature approximate laminate model joint coupling matrices thermal stresses.

Simpler criterion and flexibility of operation complexity for perfectly teleporting arbitrary n-qubit state with 2.-qubit pure state

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 2069-2073页

作者： ZUO XueQin 1,LIU YiMin 2.ZHANG ZiYun 1,ZHANG Wen 1 & ZHANG ZhanJun 1 1 key laboratory of Optoelectronic Information Acquisition & Manipulation of{2. of china,School of physics & material Science,Anhui University,Hefei 2.0039,china 2.Department of physics,Shaoguan University,Shaoguan 512.05,china 1. key laboratory of Optoelectronic Information Acquisition & Manipulation of{2. of china School of Physics & Material Science Anhui University Hefei 230039 China2. Department of Physics Shaoguan University Shaoguan 512005 China

A criterion for whether a pure-state quantum channel consisting of 2. qubits averagely distributed between two nodes can be used for perfectly teleporting an arbitrary n-qubit state via Bell-state measurements is ***,a matrix is composed of the coefficients of the known channel state and whether the matrix is unitary decides the *** the criterion is apparently different from the usual standard entanglement criterion (USEC),its applicability is enlarged and verified by other measuring *** analyses have further simplified the resultant criterion,so that a much simpler criterion than the USEC is conclusively ***,the flexibility of operation complexity between the non-unitary measurements and the unitary reconstructions is explicitly exhibited.

关键词： quantum teleportation criterion flexibility of operation complexity measuring bases reconstruction

Perfect teleportation of an arbitrary three-qubit state with the highly entangled six-qubit genuine state

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 2059-2063页

作者： YIN XiaoFeng 1,LIU YiMin 2.ZHANG ZiYun 1,ZHANG Wen 1 & ZHANG ZhanJun 1 1 key laboratory of Optoelectronic Information Acquisition & Manipulation of{2. of china,School of physics & material Science,Anhui University,Hefei 2.0039,china 2.Department of physics,Shaoguan University,Shaoguan 512.05,china 1. key laboratory of Optoelectronic Information Acquisition & Manipulation of{2. of china School of Physics & Material Science Anhui University Hefei 230039 China2. Department of Physics Shaoguan University Shaoguan 512005 China

The perfect teleportation of an arbitrary three-qubit state with the highly entangled six-qubit genuine state introduced by Borras et al.(***.A: ***.40 (2.07) 13407) is *** appropriate measuring bases the sender can take and the corresponding unitary operations the receiver should execute in terms of the sender’s measurement outcome are explicitly *** flexibility between the measurement difficulty and the reconstruction difficulty is ***,discussions and comparisons between our scheme and the recent incomplete scheme (Choudhury et al,***.A: ***.42.(2.09) 115303) are made.

关键词： quantum teleportation highly entangled six-qubit genuine state measuring bases reconstruction operation flexibility

Synthesis of superheavy nuclei with ^(2.8)U target

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3 & BAO JingDong2.4 1 key laboratory of Beam Technology and {2. Modification of ministry of education,Beijing Normal University,Beijing 100875,china 2.Department of physics,Beijing Normal University,Beijing 100875,china 3 china Institute of Atomic Energy,Beijing 102.13,china 4 Center of Theoretical Nuclear physics,National laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china key laboratory of Beam Technology and {2. Modification of ministry of education Beijing Normal University Beijing 100875 China Department of physics Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 2.8U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112.and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 2.8U target

Collision dynamics of He@C_(60)+He@C_(60) at low energies

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Science china(physics,Mechanics & Astronomy) 2008年第7期51卷 765-772页

作者： ZHAO Qiang1,2. ZHANG FengShou1,2.3 & ZHOU HongYu1,2.1 key laboratory of Beam Technology and {2. Modification of ministry of education, Institute of Low Energy Nuclear physics, Beijing Normal University, Beijing 100875, china 2.Beijing Radiation Center, Beijing 100875, china 3 Center of Theoretical Nuclear physics, National laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, china 1. key laboratory of Beam Technology and {2. Modification of ministry of education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. Beijing Radiation Center Beijing 100875 China 3. Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

A semi-empirical molecular dynamics model is developed. The central collisions of C60+C60 and He@C60+He@C60 at different incident energies are investigated based on this model. It is found that the dimer structures have been produced at proper incident energies and these fullerene dimers could be formed by a self-assembly of C60 fullerene and He@C60. The He atom has a significant effect at higher incident energy and this embedded He atom can enhance the stability of the dimer structure.

关键词： C60 He@C60 collision molecular dynamics