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CMC surfaces in the hyperbolic 3.space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2.and LI Zhenqi 1, 3.1. Institute of Mathematics, fudan university, shanghai 2.043.,{2. 2. Department of Mathematics,Sichuan Union university, Chengdu 610064,{2. 3. Department of Mathematics, Nanchang university, Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China Department of Mathematics Sichuan Union University Chengdu China Department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3.1. Department of Physics, Lishui university, Lishui 3.0}000,{3. 2. Department of Physics, {2. Jiaotong university, {2. 2.003., china 3. Institute of High Energy Physics, Beijing 100049,{3. Department of Physics Lishui University Lishui 323000 China Department of Physics Shanghai Jiaotong University Shanghai 200030 China Institute of High Energy Physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Ultrafast excitation relaxation in light-harvesting complex LH2.from *** 601

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Science china Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2. LIU Yuan3. LIU Weimin2. GUO Junhua1, XU Chunhe3.& QIAN Shixiong2.1. School of Physics and Information Optoelectronics, Henan {3., Kaifeng 475001, china 2. Physics Department,{2., shanghai 2.043., china 3. shanghai Institute of Plant Physiology, Chinese Academy of Sciences, shanghai 2.003.0} china 1. School of Physics and Information Optoelectronics Henan University 475001 Kaifeng China 2. Physics Department Fudan University 200433 Shanghai China 3. shanghai Institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2.from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783.nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.3. ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.

Superconductivity of small metal grains

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3.1. Department of Physics, shanghai Normal university, shanghai 2.02.4, china 2. Department of Physics, Southwest Normal university, Chongqing 400715, china 3. Department of Computer and Electric Technology, shanghai Business School, shanghai 2.1400, china 1. Department of Physics Shanghai Normal University 200234 Shanghai China 2. Department of Physics Southwest Normal University 400715 Chongqing China 3. Department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

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 3.0058, china 2. Imaging Department 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.

New lower bounds of classical Ramsey numbers R(6,12., R(6,14) and R(6,15)

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Chinese Science Bulletin 1998年第10期43卷 817-818页

作者： LUO Haipeng 1, SU Wenlong 2.and LI Qiao 3.1. Guangxi Academy of Sciences, Nanning 53.03., china 2. Wuzhou First Middle School, Wuzhou 543.02. china 3. {2. Jiaotong university, {2. 2.003., china Guangxi Academy of Sciences Nanning China Wuzhou First Middle School Wuzhou China shanghai Jiaotong university Shanghai China

Three new cyclic graphs are constructed by using a computer, and the lower bounds of three Ramsey numbers obtained: R(6,12.≥2.4, R(6,14)≥2.8,R(6,15)≥3.8, which fill in three blanks in the table of bounds of Ram... 详细信息

关键词： Ramsey number lower bound cyclic graph.

Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

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Science china Chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2.& LI Ping3.1. Department of Chemistry, Tongji university, shanghai 2.0092.{2. 2. Department of Chemistry, shanghai university, shanghai 2.043.,{2. 3. Department of Food, Anhui Agricultural university, Hefei 2.003.,{2. 1. Department of Chemistry Tongji University 200092 Shanghai China 2. Department of Chemistry Shanghai University 200436 Shanghai China 3. Department of Food Anhui Agricultural University 230036 Hefei China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 60 nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.43. nm, c = 0.495 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.

CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2. XU Ye1,3. SHEN Zhiqiang1,3.& LI Jingjing1,2.1. shanghai Astronomical Observatory, Chinese Academy of Sciences, shanghai 2.003.,{2. 2. Graduate School of the Chinese Academy of Sciences, Beijing 10003.,{2. 3. Joint Institute for Galaxy and Cosmology, shanghai Astronomical Observatory and the university of Science and Technology of{2., shanghai 2.003.,{2. shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate School of the Chinese Academy of Sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the university of Science Technology of china Shanghai 200030 China

The 12.O (J=1-0), 13.O (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain Observatory. Of the observed 9 sources, 13.O cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2. masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 2.566+582. in the observing field of S152.S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2. maser simulta- neously.

关键词： star formation cloud core outflow H2. maser

Localization of genes for lateral branch and female sex expression and construction of a molecular linkage map in cucumber (Cucumis sativus L.) with RAPD markers

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Progress in Natural Science:Materials International 2005年第2期15卷 48-53页

作者： LI Xiaozun1*, PAN Junsong1*, WANG Gang1, TIAN Libo3. SI Longting3. WU Aizhong2.* and CAI Run1**(1. Agriculture and Biology School, shanghai Jiaotong university, shanghai 2.1101, china 2. shanghai Academy of Agricultural Science, shanghai 2.1106, china 3. Horticulture School, Shenyang Agricultural university, Shenyang 110161, china) Agriculture and Biology School Shanghai Jiaotong University Shanghai 201101 China. Horticulture School Shenyang Agricultural University Shenyang 110161 China. shanghai Academy of Agricultural Science Shanghai 201106 China

A cucumber (Cucumis sativus L.) molecular linkage map, including 79 random-amplified polymorphic DNAs (RAPD) and two genes , lb for lateral branch and f for female sex expression, is constructed from a cross between a line, S52. with weak lateral growing ability and staminate from Dabieshan Mountains area in china and another line, S06, with strong lateral growing ability and gynoecious from Europe. The map contains nine linkage groups and spans 1110.0 cM with an average distance of 13.7 cM between loci. The lb locus is located in a longer linkage group LG-2.and flanked by two markers, OP-Q5-1 and OP-M-2.2. at 9.3.cM and 15.9 cM, respectively. In the meantime, the RAPD loci, OP-Q5-2.and BC151, in a short linkage group were found to flank f at 13.7 cM and 13.4 cM, respectively. The construction of RAPD map has paved a way for further study of the genes for lateral branch, female sex expression and other agronomic traits in cucumber.

关键词： cucumber (Cucumis sativus L.) lateral branch gynoecy RAPD genetic mapping