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Science china(physics,Mechanics & Astronomy) 2007年第3期50卷 303-310页

作者： WU YueLiang Institute of theoretical physics, Chinese Academy of Sciences, Beijing 100080, china Institute of theoretical physics Chinese Academy of Sciences Beijing China

With the hypothesis that all independent degrees of freedom of basic building blocks should be treated equally on the same footing and correlated by a possible maximal symmetry, we arrive at a 4-dimensional space-time unification model. In this model the basic building blocks are Majorana fermions in the spinor repre- sentation of 14-dimensional quantum space-time with a gauge symmetry GM4D = SO(1,3)×SU(32)×U(1)A×SU(3)F. The model leads to new physics including mirror particles of the standard model. It enables us to issue some fundamental questions that include: why our living space-time is 4-dimensional, why parity is not con- served in our world, how the stability of proton is, what the origin of CP violation is and what the dark matter can be.

关键词： gauge symmetry space-time symmetries beyond standard model and unification

Mechanisms of the pancake vortex and vortex line movement in the high T_c superconductors Bi_2Sr_2CaCu_2O_8+δ and La_(1.93)Sr0.0_7CuO_4+δ

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Science china(physics,Mechanics & Astronomy) 2007年第2期50卷 240-248页

作者： WANG WeiXian1,ZHOU Fang2,TAN Shun1,WU Huan1 & ZHANG YuHeng1 1 national High Magnetic Field laboratory,University of Science and Technology of china,Hefei 230026,china 2 national laboratory for Superconductivity,lnstitute of physics and the center for Condensed Matter physics,Chinese Academy of Sciences,Beijing 100080,china national High Magnetic Field laboratory University of Science and Technology of China Hefei China national laboratory for Superconductivity Institute of Physics and the Center for Condensed Matter Physics Chinese Academy of Sciences Beijing China

In the strict sense, it is not very clear why with magnetic field increasing, the normal-superconductive (NS) transition becomes broad for Bi2Sr2CaCu208+δ(Bi2212) while the NS transitions are almost parallel for La193Sroo7Cu04+δ(La214). In this paper, R-T relations are measured by the six-probe method. We propose a moving mechanism of the pancake vortex and vortex line for Bi2212. The theoretical curves fit the experiment data well.

关键词： superconductivity superconductive pancake vortex dynamics

X-ray flares of γ-ray bursts: Quakes of solid quark stars?

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Science china(physics,Mechanics & Astronomy) 2009年第2期52卷 315-320页

作者： XU RenXin1 & LIANG EnWei2 1 School of physics and State Key laboratory of nuclear physics and Technology, Peking University, Beijing 100871, china 2 Department of physics, Guangxi University, Nanning 530004, china School of physics and State Key laboratory of nuclear physics and Technology Peking University Beijing China Department of physics Guangxi University Nanning China

A star-quake model is proposed to understand X-ray flares of both long and short γ-ray bursts (GRBs) in a solid quark star regime. Two kinds of central engines for GRBs are available if pulsar-like stars are actually (solid) quark stars, i.e., the SNE-type GRBs and the SGR-type GRBs. It is found that a quark star could be solidified about 103 to 106 s later after its birth if the critical temperature of phase transi- tion is a few Metga-electron-volts, and then a new source of free energy (i.e., elastic and gravitational ones, rather than rotational or magnetic energy) could be possible to power GRB X-ray flares.

关键词： γ-rays bursts: X-rays neutron stars elementary particles

化学非平衡夸克-胶子物质中等质量双轻子的产生

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物理学报 2003年第11期52卷 2831-2835页

作者：贺泽君龙家丽马国亮马余刚张家驹刘波中国科学院上海原子核研究所中国科学院高能物理研究所北京100039

研究了正在进行化学平衡的富重子夸克胶子物质的双轻子产生 ,发现由于产生在RHIC能量的化学非平衡的富重子夸克胶子物质冷却慢和高的初始温度 ,导致中等质量双轻子产生重大增强 .因此 ,中等质量双轻子的增强可以是夸克胶子物质形... 详细信息

研究了正在进行化学平衡的富重子夸克胶子物质的双轻子产生 ,发现由于产生在RHIC能量的化学非平衡的富重子夸克胶子物质冷却慢和高的初始温度 ,导致中等质量双轻子产生重大增强 .因此 ,中等质量双轻子的增强可以是夸克胶子物质形成的信号 .同时 ,这个增强能补偿由于初始夸克化学势增加引起的双轻子抑制 ,因而双轻子产额的抑制不再是夸克胶子物质产生的信号 .

关键词：化学非平衡夸克-胶子物质双轻子热粲夸克夸克化学势夸克碰撞热力学平衡

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有限温度下Na4团簇的异构化

原子与分子物理学报 1999年第1期16卷 33-38页

作者：王锋张丰收柯学志朱志远兰州重离子加速器国家实验室原子核理论研究中心中国科学院近代物理研究所中国科学院上海原子核所

在紧密结合分子动力学模型基础上，对Ｎａ４的两种异构体Ｄ２ｈ和Ｃ２ｖ的结构性质随温度的变化进行了系统性研究。发现在低温时（温度Ｔ＜１００Ｋ），这两种异构体具有明显的不同；在较高温度时（温度Ｔ≥１００Ｋ），能够发现Ｃ２ｖ... 详细信息

在紧密结合分子动力学模型基础上，对Ｎａ４的两种异构体Ｄ２ｈ和Ｃ２ｖ的结构性质随温度的变化进行了系统性研究。发现在低温时（温度Ｔ＜１００Ｋ），这两种异构体具有明显的不同；在较高温度时（温度Ｔ≥１００Ｋ），能够发现Ｃ２ｖ和Ｄ２ｈ两种异构体之间的转变；在更高温度时（温度Ｔ＝４００Ｋ），这两种异构体Ｃ２ｖ和Ｄ２ｈ都处于液态。

关键词： Na4团簇异构化紧密结合分子动力学模型

Modeling the intracellular dynamics for Vif-APO mediated HIV-1 virus infection

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Chinese Science Bulletin 2010年第22期55卷 2329-2340页

作者： WANG Yi1,2 & LAI LuHua1,3 1 center for theoretical Biology, Peking University, Beijing 100871, china 2 School of physics, Peking University, Beijing 100871, china 3 BNLMS, State Key laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, china center for theoretical Biology Peking University Beijing China School of physics Peking University Beijing China BNLMS State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing China

The viral infectivity factor (Vif) was found to be essential for controlling HIV-1 virus infectivity. It targets cellular antiviral proteins in APOBEC family (APO) to trigger its fast degradation and inhibits APO packaging into nascent virion. In the present study, we propose a mathematical model to quantitatively study the intracellular dynamics of these typical virus-host interactions. Four sets of published experimental data were compared with simulation results to justify the model. Systematic parameter sensitivity and perturbation analysis showed that parameters related to APO are crucial to the infectivity of newly synthesized HIV-1 virus. Interestingly, we discovered that the synthesis rate of the viral structure protein Gag and the required number per nascent virion are optimized to achieve high virion production with minimal level of packaged APO, and large portion of model parameters are beneficial to virus only within a relatively small range. Furthermore, minor variations in several parameters related to viral protein Tat, the activator of viral RNA synthesis, were found to induce switch-like behaviors on both incorporated Vif and APO. These findings may provide new insights for understanding the high mutation rate of HIV-1 virus and its latency, as well as help identify key targets for therapeutic design.

关键词：病毒感染载脂蛋白 HIV 细胞内动力学抗病毒蛋白建模介导

Scheme for Entanglement Concentration of Unknown Multiparticle Greenberger-Horne-Zeilinger or W Class States

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Communications in theoretical physics 2007年第12期48卷 1025-1028页

作者： SONG Wei Hefei national laboratory for Physical Sciences at Microscale and Department of Modern physics,University of Science and Technology of china,Hefei 230026,china Hefei national laboratory for Physical Sciences at Microscale and Department of Modern physics University of Science and Technology of China Hefei 230026 China

We present,two schemes for concentrating unknown nonmaximally entangled Greenberger Horme-Zeilinger(GHZ) or W class *** first scheme for concentrating the nonmaximally entangled GHZ state is based on linearoptical *** second scheme for concentrating the W class states can be applied to a wide variety of atomic *** of our schemes are not postselection ones and are within the current technologies.

关键词： entanglement concentration GHZ class states W class states

Structural and mechanical properties of amorphous carbon films deposited by the dual plasma technique

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Journal of University of Science and Technology Beijing 2008年第5期15卷 622-626页

作者： Yaohui Wang,Xu Zhang,Xianying Wu,Huixing Zhang,and Xiaoji Zhang Key laboratory of the Ministry of Education of china for Beam Technology and Material Modification,Institution of Low Energy nuclear physics,Beijing Normal University Beijing Radiation center,Beijing 100875,china Key laboratory of the Ministry of Education of china for Beam Technology and Material Modification Institution of Low Energy Nuclear Physics Beijing Normal University Beijing Radiation center Beijing 100875 China

Direct current metal filtered cathodic vacuum arc （FCVA） and acetylene gas （C2H2） were wielded to synthesize Ti-containing amorphous carbon films on Si （100）. The influence of substrate bias voltage and acetylene gas on the microstructure and mechanical properties of the films were investigated. The results show that the phase of TiC in the （111） preferential crystallographic orientation exists in the film,and the main existing pattern of carbon is sp2. With increasing the acetylene flow rate,the contents of Ti and TiC phase of the film gradually reduce; however,the thickness of the film increases. When the substrate bias voltage reaches -600 V,the internal stress of the film reaches 1.6 GPa. The micro-hardness and elastic modulus of the film can reach 33.9 and 237.6 GPa,respectively,and the friction coefficient of the film is 0.25.

关键词： metal containing amorphous carbon amorphous carbon films filtered arc acetylene flow rate bias voltage structure and properties

The principle of relativity, kinematics and algebraic relations

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2,3, WU HongTu4 & ZHOU Bin5 1Institute of theoretical physics, Chinese Academy of Sciences, Beijing 100190, china 2Institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049, china 3theoretical physics center for Science Facilities, Chinese Academy of Sciences, Beijing 100049, china 4Department of Mathematics, Capital Normal University, Beijing 100048, china 5Department of physics, Beijing Normal University, Beijing 100875, china Institute of theoretical physics Chinese Academy of Sciences Beijing China Institute of High Energy physics Chinese Academy of Sciences Beijing China theoretical physics center for Science Facilities Chinese Academy of Sciences Beijing China Department of Mathematics Capital Normal University Beijing China Department of physics Beijing Normal University Beijing China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

Constraints of f(R) gravity in Palatini approach with observational Hubble data

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Science china(physics,Mechanics & Astronomy) 2011年第8期54卷 1378-1383页

作者： ZHAI ZhongXu & LIU WenBiao Department of physics, Institute of theoretical physics, Beijing Normal University, Beijing 100875, china Department of physics Institute of Theoretical Physics Beijing Normal University Beijing China

We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2/2 to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.41) by OHD only and (Ωm0, n) = (0.23, 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.

关键词： f(R) gravity OHD CMB BAO accelerating expansion dark energy