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Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3)MnO_3 system

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Science china(physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2.,YAN GuoQing 1,3 ,CAI ZhiRang 1 ,PI Li 2.,ZHANG Bei 2.&TONG Wei 2.1 department of physics,Suzhou College,Suzhou 2.4000,{2. 2.Structure Research Laboratory,university of Science and Technology of china,Hefei 2.002.,{2. 3 National Laboratory of Solid State Microstructures,physics department,Nanjing university,Nanjing 2.0093,{2. 1. department of physics Suzhou College Suzhou 234000 China 2. Structure Research Laboratory University of Science and Technology of China Hefei 230026 China 3. National Laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural Science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2. Wu Yigen3 and Guo Shengli3(1. College of Life Sciences, Zhejiang university, Hangzhou 310058, china 2. Imaging {2. of Tongji Hospital of Tongji university, Shanghai 2.0065, china 3. College of Mathematics and physics, Nanjing university of Information Science and Technology, Nanjing 2.0044, china) College of Life Sciences Zhejiang University Hangzhou 310058 China Imaging department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

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 Ministry of Education of china,School of physics & Material Science,Anhui {2.,Hefei 2.0039,china 2.department of physics,Shaoguan {2.,Shaoguan 512.05,china 1. Key Laboratory of Optoelectronic Information Acquisition & Manipulation of Ministry of Education 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

Local electronic structure and magnetic properties of 3d transition metal doped GaAs

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Science china(physics,Mechanics & Astronomy) 2008年第5期51卷 470-480页

作者： LIN He1 & DUAN HaiMing2. department of Chemistry,Institute of Applied Chemistry,Xinjiang university,Urumqi 830046,{2. 2.0} of physics,Xinjiang university,Urumqi 830046,{2. 1. department of Chemistry Institute of Applied Chemistry Xinjiang University Urumqi 830046 China 2. department of physics Xinjiang University Urumqi 830046 China

The local electronic structure and magnetic properties of GaAs doped with 3d transition metal (Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were studied by using discrete variational method (DVM) based on density functional theory. The calculated result indicated that the magnetic moment of transition metal increases first and then decreases, and reaches the maximum value when Mn is doped into GaAs. In the case of Mn concentration of 1.4%, the magnetic moment of Mn is in good agreement with the experimental result. The coupling between impure atoms in the system with two impure atoms was found to have obvious variation. For different transition metal, the coupling between the impure atom and the nearest neighbor As also has different variation.

关键词： diluted magnetic semiconductor density functional theory 3d transition metal cluster model electronic structure

STUDY ON THE MISCIBILITY OF DYNAMICALLY VULCANIZED EPDM/PP BLEND BY POSITRON ANNIHILATION SPECTROSCOPY

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Chinese Journal of Polymer Science 2000年第2期18卷 123-128页

作者： Tao Jiang Xue-liang Jiang Shi-yuan Cheng Yi-qun Dai Shao-jie Wang Bo Wang Faculty of Chemistry & Material, hubei university, Wuhan 430062.{2. department of physics, Wuhan university, Wuhan 430072.{2. hubei Univ Fac Chem & Mat Wuhan 430062 Peoples R China Wuhan Univ Dept Phys Wuhan 430072 Peoples R China

Positron annihilation spectroscopy (PAS) was utilized to investigate the relationship between the free-volume hole properties and miscibility of dynamically vulcanized EPDM/PP blend. The results showed that the noncrystalline region of PP and EPDM in the blend was partially miscible and the miscibility of the blend became worse when the weight percent of EPDM was <50%. This was also demonstrated by DMTA and mechanical properties of the blends with various compositions.

关键词： EPDM PP dynamic vulcanization miscibility PAS

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 Ministry of Education of china,School of physics & Material Science,Anhui {2.,Hefei 2.0039,china 2.department of physics,Shaoguan {2.,Shaoguan 512.05,china 1. Key Laboratory of Optoelectronic Information Acquisition & Manipulation of Ministry of Education 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

Stochastic bi-resonance induced by external noise for Ca^2. signaling in hepatocytes

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Science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2.HOU Zhonghuai1 & XIN Houwen1 1.department of Chemical physics,{2. of Science and Technology of china,Hefei 2.002.,china 2.College of physics and Electronic Information,Anhui Normal {2.,Wuhu 2.1000,china 1. department of Chemical physics University of Science and Technology of China 230026 Hefei China 2. College of physics and Electronic Information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2. oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2. oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

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 Material Modification of Ministry of Education, Beijing Normal university, Beijing 100875, china 2. {2. 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.

Virtualities of quark and gluon in QCD vacuum

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1439-1447页

作者： ZHOU LiJuan1, QIN SongMei2. WU Qing3 & MA WeiXing4 1 Collaboration Group of Hadron physics and Non-perturbative QCD Study, Guangxi university of Tech- nology, Liuzhou 545006,{2. 2.department of physics, Guangxi university, Nanning 540003,{2. 3 department of physics, Qingdao university, Qingdao 2.6071,{2. 4 Institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049,{2. 1. Collaboration Group of Hadron physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China 2. department of physics Guangxi University Nanning 540003 China 3. department of physics Qingdao University Qingdao 266071 China 4. Institute of High Energy physics Chinese Academy of Sciences Beijing 100049 China

The non-local vacuum condensates of quantum chromodynamics (QCD) describe the distributions of quarks and gluons in the non-perturbative QCD vacuum state. Physically, this means that vacuum quarks and gluons have a nonzero mean-squared momentum in the vacuum, called virtuality. The quark virtuality is given by the ratio of the local quark-gluon mixed vacuum condensate to the quark local vacuum condensate. The gluon virtuality is expressed by gluon vacuum condensates and four-quark vacuum condensates. We study the two virtualities by solving Dyson-Schwinger Equations and calculating quark and gluon vacuum condensates. Our theoretical results for quark virtuality are in good agreement with many other theoretical model predictions such as QCD sum rules and lattice QCD calculations. Our calculation on gluon virtuality is initial and the results are quite interesting.

关键词： quark gluon virtuality QCD vacuum condensate non-perturbative QCD