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Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science china Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2. WANG Jin3, WU Yishi1, YUAN Gu3, AI Xicheng1, WANG Li4 & ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, Chinese Academy of Sciences, beijing 1.0080,{2. 2. School of Life Science and Technology, beijing institute of Technology, beijing 100081,{2. 3. College of Chemistry and Molecular Engineering, Peking University, beijing 1.0080,{2. 4. center for condensed matter {12., institute of physics, Chinese Academy of Sciences, beijing 1.0080,{2. Correspondence should be addressed to Ai Xicheng and Zhang Jianping State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China School of Life Science and Technology Beijing Institute of Technology Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China center for condensed {2. physics Institute of Physics Chinese Academy of Sciences Beijing China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32.ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

High-pressure synthesis and properties of CeO_2.ZrO_2.solid solution

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Chinese Science Bulletin 2001年第10期46卷 801-806页

作者： XU Dapeng, WANG Quanyong, LU Zhe, LIU Zhiguo, ZHANG Gongmu & SU Wenhui1. Department of physics, Jilin University, Changchun 13002. china 2. International {2. for Materials physics, Chinese Academy of Sciences, Shenyang 110015, china 3. {2. for condensed matter and Radiation physics, china {2. of Advanced Science and Technology (World Laboratory), beijing 1.0080, china Department of physics Jilin University Changchun China International center for Materials physics Chinese Academy of Sciences Shenyang China center for condensed {2. and Radiation physics China Center of Advanced Science and Technology (World Laboratory) Beijing China

Using nanoparticles of CeO2.and ZrO2.prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2.solid solution (c-Ce0.5Z0.5O2. has been synthesized under 3.1 GPa at 1073 K for the first time. The structure of the c-Ce0.5Zr0.5O2.has not been changed before and after annealing at 773 K for 1 h. Only an unknown EPR signal (g =1.990) has been observed in the c-Ce0.5Zr0.5O2.and not varied after annealing at 773 K for 1 h, which exhibited that there exists no Ce3+ in the c-Ce0.5Zr0.5O2.and the Ce4+ has not been reduced into Ce3+ after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (a =1.2.10-5 S/cm at 82. K, σ=2.1 ×10-3 S/cm at 112. K) is the same as that of CeO2. but smaller than that of Y2.3-stabilized ZrO2. A marked curvature at T = 82. K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 82. K is lower than that above 82. K, and the reason has been discussed.

关键词： CeO2.ZrO2 nanocrystalline high-pressure and -temperature solid-state reaction solid solution.

A 3.9 V polyanion-type cathode material for Li-ion batteries

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Progress in Natural Science:Materials International 2011年第3期21卷 211-215页

作者： Lei LIU,Bin ZHANG,Xue-jie HUANG beijing National Laboratory for condensed {2. physics, institute of physics,Chinese Academy of Sciences,beijing,100190,china beijing National Laboratory for condensed {2. physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

Monoclinic phase LiFeSO4F was synthesized by a simple fast solid state reaction from the mixture of FeSO4·7H2. and LiF pulverized by high energy ball milling.m-LiFeSO4F was confirmed by GITT measurement to be a 3.9 V polyanion-type cathode materials for Li-ion *** electrochemical activity can be enhanced by addition of carbon.A discharge capacity of 105 mA·h/g (70%of theoretical value) was achieved for a m-LiFeSO4F/CNT *** separation behavior during lithium extraction and insertion was observed by ex-situ XRD test.

关键词： LiFeSO4F polyanion cathode Li-ion battery

Existence of solutions for the dynamic equation of ferrimagnets

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Progress in Natural Science:Materials International 2007年第11期17卷 1279-1283页

作者： Zeng Ming1, Guo Boling2.and Cheng Caozong1(1. College of Applied Sciences, beijing University of Technology, beijing 10002.,{2. 2. center for Nonlinear Studies, institute of Applied physics and Computational Mathematics, beijing 100088,{2.) College of Applied Sciences Beijing University of Technology Beijing 100022 China center for Nonlinear Studies Institute of Applied Physics and Computational Mathematics Beijing 100088 China

Ferrimagnet is a kind of basic and important multi-sublattice magnet material. It has attracted more and more attention of physicists and mathematicians. Many results of solitons and numerical computations on this topic have appeared. In this article, the dynamic equation for an isotropic ferrimagnet with two non-equivalent sublattices is studied, existence of weak solutions in multi dimension case is proved through the penalized method, the uniqueness and smoothness of the solution in one dimension case are also obtained by the relation between this equation and hyperbolic equation.

关键词： ferrimagnet weak solutions penalized method finite difference method

Magnetic Field Effects on Quantum-Dot Spin Valves

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Communications in Theoretical physics 2009年第3期51卷 555-562页

作者： GAO Jin-Hua,~1 SUN Qing-Feng,~1 and XIE Xin-Cheng~(1,2.1 beijing National Lab for condensed {2. physics and institute of physics, Chinese Academy of Sciences,beijing 1.0080, china2.Department of physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA beijing National Lab for condensed {2. physics and institute of physics Chinese Academy of Sciences Beijing 100080 China Department of physics Oklahoma State University Stillwater Oklahoma 74078 USA

We study the magnetic field effects on the spin-polarized transport of the quantum dot (QD) spin valve inthe sequential tunneling regime. A set of generalized master equation is derived. Based on that, we discuss the collinearand noncollinear magnetic field effects, respectively. In the collinear magnetic field case, we find that the Zeeman splittingcan induce a negative differential conductance (NDC), which is quite different from the one found in previous *** has a critical polarization in the parallel arrangement and will disappear in the antiparallel configuration. In thenoncollinear magnetic field case, the current shows two plateaus and their angular dependence is analyzed. Althoughsometimes the two current plateaus have similar angular dependence, their mechanisms are different. Our formalism isalso suitable for calculating the transport in magnetic molecules, in which the spin splitting is induced not by a magneticGeld but by the intrinsic magnetization.

关键词： spin value spintronics quantum dot

Atomic force microscopy studies of SrTiO_(3)(001)substrates treated by chemical etching and annealing in oxygen

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 459-468页

作者： WANG Xu1, FEI Yiyan1, LU Huibin1, JIN Kui-juan1, ZHU Xiangdong1,3, CHEN Zhenghao1, ZHOU Yueliang1 & YANG Guozhen1 1. beijing National Laboratory for condensed {2. physics,institute of physics,Chinese Academy of Sciences,beijing 1.0080,china 2. Department of physics,University of California, Davis,California,USA beijing National Laboratory for condensed {2. physics Institute of Physics Chinese Academy of Sciences Beijing China Department of physics University of California Davis USA

The SrTiO3 (001) substrates treated by chemical etching in NH4F-buffered HF solution and annealing in oxygen ambient have been studied by an atomic force microscopy (AFM). The SrTiO3 substrates with TiO2.termineted and atomically smooth surfaces and single unit cell steps have been obtained. The surface morphologies of SrTiO3 substrates strongly depend on the treated conditions and the quality of the substrates.

关键词： SrTiO3, AFM, surface morphology, surface defects.

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3 1. china institute of Atomic Energy, {2. 102.13, china 2. center of Nuclear Theoretical physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 730000, china 3. institute of Theoretical physics, Chinese Academy of Sciences, beijing 1.0080, china Correspondence should be addressed to Rong Jian (email: jrong@***) china institute of Atomic Energy Beijing China center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China institute of Theoretical physics Chinese Academy of Sciences Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research center, institute of Atmospheric {2., Chinese Academy of Sciences, beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the Chinese Academy of Sciences, beijing 100049, china Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the Chinese Academy of Sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

New quantum tunneling steps in Mn_(11)Cr/Mn_(12. mixed crystal

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1769-1771页

作者： ZHOU YuRong1,LI YanRong1,FAN ZhenJun2.& WANG YunPing1 1beijing National Laboratory for condensed {2. physics,institute of physics,Chinese Academy of Sciences,beijing 100190,china 2.chool of Materials Sciences and Technology,china University of Geosciences,beijing 430074,china beijing National Laboratory for condensed {2. physics Institute of Physics Chinese Academy of Sciences Beijing China School of Materials Sciences and Technology China University of Geosciences Beijing China

Magnetic properties of Mn11Cr and Mn12.mixed crystal at low temperature are studied.A new set of quantum tunneling steps discovered in magnetization curves suggests that there may exist another kind of single molecula... 详细信息

关键词： quantum tunneling molecular magnet magnetization curve