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Science China(physics,Mechanics & Astronomy) 2009年第7期52卷 1011-1020页

作者： GU Juan1,2. WANG ShanYing2.& GOU BingCong1 1 department of physics, Beijing Institute of Technology, Beijing 100081, China 2.department of physics, Tsinghua University, Beijing 100084, China department of physics Beijing Institute of Technology Beijing 100081 China department of physics Tsinghua University Beijing 100084 China

The geometrical structure, stability, magnetism, and electronic structure of bimetallic clusters AuM2.and Au2.2. where M are 4d transition metal elements, are investigated systematically by using the first-principles method based on density functional theory. The calculation results show that there is a large amount of low-energy isomers with the very similar structure. AuM2.and Au2.2.clusters display dramatic magnetism. The magnetic moment of the 4d element is either enhanced or weakened with respect to the bulk value, which is largely dependent on the orbital exchange-splitting.

关键词： density functional theory first-principles cluster electronic structure magnetism

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science China(physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 department of physics, China University of Petroleum, Dongying 2.7061, China 2.department of physics, Beijing Normal University, Beijing 100875, China department of physics China University of Petroleum Dongying 257061 China department of physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

A modified multi-reference second order perturbation theory

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中国科学：化学英文版 2010年第4期53卷 933-939页

作者： LI AnYang1, HAN HuiXian2. SUO BingBing3, WANG YuBin3 & WEN ZhenYi3 1Institute of Computational Chemistry, Chongqing University of Post and Telecommunications, Chongqing 400065, China 2.0} of physics, Northwest University, Xi’ an 710069, China 3Institute of Modern physics, Northwest University, Xi’ an 710069, China 1. Institute of Computational Chemistry Chongqing University of Post and Telecommunications Chongqing 400065 China2. Department of Physics Northwest University Xi’ an 710069 China3. Institute of Modern Physics Northwest University Xi’ an 710069 China

A new scheme with extended model space is proposed to improve the calculation of multi-reference second order perturbation theory (MRPT2.. The new scheme preserves the concise code structure of the original program, and avoids intruder states in constructions of the potential energy surface, which is confirmed by a series of comparable calculations. The new MRPT2.program is an available tool for the research of molecular excited states and electronic spectrum.

关键词： perturbation theory multi-reference intruder state

Properties of Rotating Neutron Stars in the Relativistic σ-ω Model

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Communications in Theoretical physics 2004年第1期41卷 51-54页

作者： WEN De-Hua~(1,2. CHEN Wei~3 WANG Xian-Ju~1 AI Bao-Quan~1 LIU Guo-Tao~1 LIU Liang-Gang~1 1 department of physics,Zhongshan University,Guangzhou 5102.5,China2.department of physics,South China University of Technology,Guangzhou 510641,China3 department of physics,Jinan University,Guangzhou 510632.China department of physics Jinan University Guangzhou 510632 China

The properties such as the moment of inertia,the surface redshift and the radius of gyration of rotatingneutron stars in the relativistic σ-ω model are studied with the Hartle’s *** relation between the angularvelocity of the fluid relative to the local inertial frame and the uniform angular velocity relative to the infinite iscalculated.

关键词： relativistic σ-ω model rotating neutron star equation of state

Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2.3 1 Key Laboratory of Particle Astrophysics,Institute of High Energy physics,Chinese Academy of Sciences,Beijing 100049,China 2.{2. of physics & Center for Astrophysics,Tsinghua University,Beijing 100084,China 3 {2. of Engineering physics & Center for Astrophysics,Tsinghua University,Beijing 100084,China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China department of physics & Center for Astrophysics Tsinghua University Beijing China department of Engineering physics & Center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2. ZHAO Zongci2. DONG Wenje2.and YANG Bao3 (1.department of Atmospheric Sciences, School of physics, Peking University, Beijing 100871, China 2. Laboratory for Climate Studies, China Meteorological Administration, Beijing 100081, China 3. Institute of Cold and Arid Regions Environmental and Engineering, Chinese Academy of Sciences, Lanzhou 730000, China) [a] department of Atmospheric Sciences School of Physics Peking University Beijing China [b] Laboratory for Climate Studies China Meterological Administration Beijing China [c] Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2. All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3) The warming from 1975 to 2.00 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 2.th century.

Two-dimensional simulation of Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect

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Progress in Natural Science:Materials International 2007年第12期17卷 1389-1396页

作者： Hu Jun1 and Yin Xieyuan2.1. Institute of Applied physics and Computational Mathematics, Beijing 100088, China 2. department of Modern Mechanics, University of Science and Technology of China, Hefei 2.002., China) Institute of Applied physics and Computational Mathematics Beijing 100088 China department of Modern Mechanics University of Science and Technology of China Hefei 230027 China

Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect are directly simulated by a mixed finite element method. A temperature perturbation is used as an initial disturbed source for the basic parallel flows. The whole spatio-temporal evolution of the binary fluid flows is exhibited: initially only the disturbed mode with the wavenumber k=π is amplified while others are damped, and continuously the amplified mode grows further and the nonlinear effect becomes important; after a nonlinear evolution transition the flow system evolves finally into a periodic right traveling wave.

关键词： Poiseuille-Rayleigh-Bénard flow Soret effect through-flow.

Topological chirality and achirality of the closed circular DNAs

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Chinese Science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. department of Chemical physics, University of Science and Technology of China, Hefei 2.002., China 2. department of Chemistry, Lanzhou University, Lanzhou 730000, China Depaitment of Chemical physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science China(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. China 2. department of physics, Beijing Normal University, Beijing 100875, China 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, China 4. Institute of Modern physics, Fudan University, Shanghai 2.0433, China Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China department of physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern physics Fudan University Shanghai 200433 China

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Algorithm of graph isomorphism with threedimensional DNA graph structures

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Progress in Natural Science:Materials International 2005年第2期15卷 86-89页

作者： LIU Guangwu 1,2., YIN Zhixiang 1,3, XU Jin1 and DONG Yafei1(1. department of Control Science and Engineering, Hua Zhong University of Science and Technology, Wuhan 430074, China 2. College of Transportation, Wuhan University of Technology, Wuhan 430063, China 3. department of Mathematics and {2., Anhui University of Science and Technology, Huainan 2.2.01, China) department of Control Science and Engineering Hua Zhong University of Science and Technology Wuhan 430074 China. College of Transportation Wuhan University of Technology Wuhan 430063 China. department of Mathematics and physics Anhui University of Science and Technology Huainan 232001 China

An algorithm for solving the graph isomorphism problem with 3-D DNA structures is proposed in this paper. The k-armed branched junction molecules are used to code k-degree vertices. Double stranded molecules are used to code edges. Then the molecules are mixed in a tube to be ligated. The result can be detected by gel electrophoresis. The time complexity of the algorithm is O(n2., where n is the number of vertices of the graph.

关键词： DNA computing DNA graph structure graph isomorphism