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Model for Unidirectional Movement of Axonemal and Cytoplasmic Dynein Molecules

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Acta Biochimica et Biophysica Sinica 2006年第10期38卷 711-724页

作者： Ping XIE* Shuo-Xing DOU Peng-Ye WANG laboratory of Soft matter {2.,beijing national laboratory for condensed matter {2.,institute of physics,chinese academy of sciences,beijing 100080,China laboratory of Soft matter {2. Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of SciencesBeijing 100080 China

A model for the unidirectional movement of dynein is presented based on the structuralobservations and biochemical experimental results *** this model,the binding affinity of dynein formicrotubule (MT) is independent of its nucleotide state and the change between strong and weak MT-bindingis determined naturally by the variation of relative orientation between the stalk and MT,as the stalk rotatesfollowing nucleotide-state *** the enigmatic communication from the adenosine triphosphate(ATP)-binding site in the globular domain to the far MT-binding site in the tip of the stalk,which is aprerequisite in conventional models,is not *** the present model,the previous experimentalresults such as the effect of ATP and adenosine diphosphate (ADP) bindings on dissociation of dynein fromMT,the movement of single-headed axonemal dyneins at saturating ATP concentration,the load dependenceof step-size for the movement of two-headed cytoplasmic dyneins and the dependence of stall force on ATPconcentration can be well explained.

关键词： dynein mechanism mechanochemistry molecular motor

Research progress in the inner surface modification of metal tubes by plasma processing

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Progress in Natural Science:Materials International 2006年第11期16卷 1119-1126页

作者： ZHANG Guling~ 1,2.**, WU Xingfang~1, GU Weichao~2. CHEN Guangliang~2. FENG Wenran~2. NIU Erwu~2. LI Li~2. L Guohua~2. CHEN Huan~2. FAN Songhua~2. LIU Chizi~2.and YANG Size~2.1. School of Material Science and Engineering, University of Science and Technology beijing, beijing 100083, China 2. beijing national laboratory for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, China) School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China beijing national {2. for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The recent progress in inner surface hardening of tubes by plasma processing is summerized. Several techniques of inner surface plasma source ion implantation and deposition are introduced, and their advantages and disadvantages are discussed. The basic principles, technical features and new progress of inner surface plasma source ion implantation methods for metal tubes, which were developed in our laboratory, are described in detail. And perspectives of the future technical development for inner surface ion implantation of tubes are presented.

关键词： PSII metal tubes inner surface surface modification.

Oxygen pressure dependent electro-resistance in La_(0.9)Sr_(0.1)MnO_3 thin films grown by laser molecular beam epitaxy

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Science China(physics,Mechanics & Astronomy) 2008年第3期51卷 232-236页

作者： OUYANG SiHua1,2.WANG ChunChang2.LIU GuoZhen2.HE Meng2. JIN KuiJuan2.DANG ZhiMin1 & L HuiBin2. College of Materials Science and Engineering,beijing University of Chemical Technology,beijing 10002.,China {2.,institute of physics,chinese academy of sciences,beijing 100080,China College of Materials Science and Engineering Beijing University of Chemical Technology Beijing China beijing national {2. for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing China

We report here studies on the influence of oxygen pressure on the electroresis-tance behavior of La0.9Sr0.1MnO3 thin films fabricated by laser molecular beam epi-taxy. It was found that the film deposited at lower oxygen pressure shows larger c-axis parameter,higher resistance,and more distinct electroresistance. These results reveal that the electroresistance of manganite thin films can be tuned by the conditions of film fabrication.

关键词： La0.9Sr0.1MnO3 thin film electroresistance effect laser molecular beam epitaxy

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 {2. for condensed matter physics, institute of physics,chinese academy of sciences,beijing,100190,China beijing national {2. for condensed matter 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

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science China(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China 2. Center for condensed {2. physics, institute of physics, chinese academy of sciences, beijing 100080, China 3. BSRF, institute of High Energy physics, chinese academy of sciences, beijing 100039, China Key laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao China Center for condensed matter {2. Institute of Physics Chinese Academy of Sciences Beijing China BSRF Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Single-molecule studies of DNA by molecular combing

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Progress in Natural Science:Materials International 2007年第5期17卷 493-499页

作者： Liu Yuying, Wang Pengye and Dou Shuoxing (College of Science, China Agricultural University, beijing 100083, China laboratory of Soft {2. physics, beijing national laboratory for condensed {2. physics, institute of physics, chinese academy of sciences, beijing 100080, China) College of sciences China Agricultural University Beijing 100083 China laboratory of Soft matter {2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China beijing national {2. for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Molecular combing is a powerful method for aligning a large array of DMA molecules onto a surface. It is a process whereby DNA molecules are stretched and aligned on a glass surface by the force via fluid flow. The ability to comb up to several hundred DNAs on a single cover slip allows for a statistically significant number of measurements to be made. These features make molecular combing an attractive tool for genomic studies, such as DNA replication, DNA transcription, DNA-protein interaction and so on. In this review article, we discuss the molecular combing principle, method and its applications.

关键词： DNA molecule molecular combing DNA-protein interaction.

The size effect on transport properties of colossal magnetoresistance materials La_(0.67)Ca_(0.33)MnO_3

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Science China(physics,Mechanics & Astronomy) 2008年第3期51卷 251-257页

作者： LI PeiGang1,2.LEI Ming1,2.GUO YanFeng2.GUO Xi2.CHEN LeiMing2. TANG WeiHua1,2.SONG PengYun3 & CHEN JinPing3 1 Department of physics,Center for Optoelectronics Materials and Devices,Zhejiang Sci-Tech University,Hangzhou 310018,China 2.national {2. for condensed matter physics,institute of physics,chinese academy of sciences,beijing 100080,China 3 Department of physics,Peking University,beijing 100875,China Department of physics Center for Optoelectronics Materials and Devices Zhejiang Sci-Tech University Hangzhou China national laboratory for {2. matter physics Institute of Physics Chinese Academy of Sciences Beijing China Department of physics Peking University Beijing China

High quality La0.67Ca0.33MnO3 (LCMO) film was deposited via a novel pulsed electron deposition technique on SrTiO3(100) single crystal substrate. The micro-bridge with different widths was fabricated by using electron beam lithography (EBL) technique and their transport properties were studied. For the micro-bridges with width of 2.and 1.5 μm,the insulator-to-metal transition temperature (TP) keeps un-changed compared with the film. For the micro-bridges with width of 1 μm,the TP shifts towards the lower temperature by 50 K. When the width decreases down to 500 nm,the insulator-to-metal transition disappears. The magnetoresistance be-havior of these micro-bridges was studied,and the results show that the low field magnetoresistance (LFMR) decreases and the high field magnetoresistances (HFMR) keep almost unchanged as the width of micro-bridge is reduced.

关键词： colossal magnetoresistance pulsed electron deposition electron beam lithography electrical transport properties

Superconductivity at 36 K in gadolinium-arsenide oxides GdO_(1-x)F_xFeAs

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Science China(physics,Mechanics & Astronomy) 2008年第6期51卷 719-722页

作者： CHENG Peng, FANG Lei, YANG Huan, ZHU XiYu, MU Gang, LUO HuiQian, WANG ZhaoSheng & WEN HaiHu national laboratory for Superconductivity, {2., chinese academy of sciences, beijing 100190, China beijing national laboratory for condensed matter physics, {2., chinese academy of sciences, beijing 100190, China national laboratory for Superconductivity Institute of Physics Chinese Academy of Sciences Beijing China beijing national {2. for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing China

In this paper we report the fabrication and superconducting properties of GdO1-xFxFeAs. It was found that when x is equal to 0.17, GdO0.83F0.17FeAs is a su-perconductor with the onset transition temperature Tcon ≈ 36.6 K. Resistivity anomaly near 130 K was observed for all samples up to x = 0.17, and such a phenomenon is similar to that of LaO1-xFxFeAs. Hall coefficient indicates that GdO1-xFxFeAs is conducted by electron-like charge carriers.

关键词： iron-based superconductor high-temperature superconductor

Pairwise entanglement and local polarization of Heisenberg model

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Science China(physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： XI XiaoQiang1,2. ZHANG Tao3, YUE RuiHong3,4 & LIU WuMing2.1 Department of Applied Mathematics and physics, Xi’an institute of Post and Telecommunications, Xi’an 710061, China {2., institute of physics, chinese academy of sciences, beijing 100080, China 3 institute of Modern physics, Northwest University, Xi’an 710069, China 4 Department of physics, Ningbo University, Ningbo 3152.1, China Department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an China beijing national {2. for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing China institute of Modern physics Northwest University Xi’an China Department of physics Ningbo University Ningbo China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2.for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3412.(for odd-qubit chain) or 0.3491 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement