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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 HuiBin21 College of Materials Science and Engineering,beijing University of Chemical Technology,beijing 100029,china 2 beijing national laboratory for condensed matter physics,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 laboratory 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

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 laboratory 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.

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 beijing national laboratory for condensed matter physics, 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 315211, china Department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an China beijing national laboratory 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

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 physics,beijing national laboratory for condensed matter physics,institute of physics,chinese academy of sciences,beijing 100080,china laboratory of Soft matter physics 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

Anomalous Hall effect in perpendicular CoFeB thin films

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chinese physics B 2014年第4期23卷 9-17页

作者：朱涛 institute of physics and beijing national laboratory for condensed matter physics Chinese Academy of Sciences

Our recent research achievements in the perpendicular magnetic anisotropy （PMA） properties of the CoFeB sand- wiched by MgO and tantalum layers are summarized. We found that the PMA behaviors of Ta/CoFeB/MgO and MgO/CoFeB/Ta thin films are different. The larger PMA in the latter film is related to the lower magnetization of CoFeB deposited on MgO. Furthermore, we have demonstrated a large anomalous Hall effect in perpendicular CoFeB thin fihn. Our results show large anomalous Hall resistivity, large longitudinal resistivity, and low switching field can be achieved, all at the same time, in the perpendicular CoFeB thin film. Anomalous Hall effect with high and linear sensitivity is also found in an MgO/CoFeBFFa thin film with a thick MgO layer, which opens a door tbr future device applications of perpendicular ferromagnetic thin films.

关键词： anomalous Hall effect perpendicular magnetic anisotropy magnetic properties of interfaces

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 matter physics, beijing national laboratory for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, china) College of sciences China Agricultural University Beijing 100083 China laboratory of Soft matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China beijing national laboratory 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.

chinese national clinical practice guidelines on the prevention,diagnosis,and treatment of early gastric cancer

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chinese Medical Journal 2024年第8期137卷 887-908页

作者： Peng Li Ziyu Li Enqiang Linghu Jiafu Ji Society of Digestive Endoscopy of the chinese Medical Association Colorectal Surgery Group of the chinese Medical Association chinese Association of Gastroenterologists&Hepatologists national Clinical Research Center for Digestive Diseases chinese Medical Journal Clinical Practice Guideline Collaborative Department of Gastroenterology Beijing Friendship HospitalCapital Medical UniversityNational Clinical Research Center for Digestive DiseaseBeijing 100050China Department of Gastrointestinal Surgery Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Peking University Cancer Hospital and InstituteBeijing 100142China Department of Gastroenterology and Hepatology the First Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China 不详

Background:Gastric cancer is one of the most common malignant tumors in the digestive system in *** comprehensive practice guidelines for early gastric cancer in china are currently ***,we created the chinese national clinical practice guideline for the prevention,diagnosis,and treatment of early gastric ***:This clinical practice guideline(CPG)was developed in accordance with the World Health Organization’s recommended process and with the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)in assessing evidence *** used the Evidence to Decision framework to formulate clinical recommendations to minimize bias and increase transparency in the CPG development *** used the Reporting Items for practice Guidelines in HealThcare(RIGHT)statement and the Appraisal of Guidelines for Research and Evaluation II(AGREE II)as reporting and conduct guidelines to ensure completeness and transparency of the ***:This CPG contains 40 recommendations regarding the prevention,screening,diagnosis,treatment,and follow-up of early gastric cancer based on available clinical studies and *** provide recommendations for the timing of Helicobacter pylori eradication,screening populations for early gastric cancer,indications for endoscopic resection and surgical gastrectomy,follow-up interval after treatment,and other ***:This CPG can lead to optimum care for patients and populations by providing up-to-date medical *** intend this CPG for widespread adoption to increase the standard of prevention,screening,diagnosis,treatment,and follow-up of early gastric cancer;thereby,contributing to improving national health care and patient quality of life.

关键词： Early gastric cancer Prevention Screening Diagnosis Treatment Follow-up

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 matter physics, institute of physics,chinese academy of sciences,beijing,100190,china beijing national laboratory 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 FeSO4·7H2O 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

An Explicit Function Expression for dc Bias and Temperature Dependence of Magnetoresistances in Magnetic Tunnel Junctions

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Journal of Materials Science & Technology 2002年第6期18卷 497-501页

作者： Xiufeng HANState Key laboratory of Magnetism, institute of physics and Center of condensed matter physics, chinese academy of sciences, beijing 100080, china chinese Acad Sci Inst Phys State Key Lab Magnetism Beijing 100080 Peoples R China chinese Acad Sci Ctr Condensed Matter Phys Beijing 100080 Peoples R China

An explicit function expression for the bias voltage or/and temperature dependences of tunnel magnetoresistance ratio and resistances were obtained with a unique set of intrinsic parameters. Two of these intrinsic parameters are the Curie temperature TC and the density of state (DOS) for itinerant majority and minority electrons ξ(ρM/ρm), which are the eigen parameters of ferromagnetic electrodes. Others are the spin-dependent matrix-element ratio (i.e., |Td|2/|TJ|2 ) and the anisotropic-wavelength-cutoff energy ECγ of spin-wave spectrum in magnetic tunnel junction (MTJ), which are the structure parameters of an MTJ. These intrinsic parameters can be predetermined using the experimental measurement or, in principle, using the first-principle calculation method for an MTJ with the three key layers of FM/I/FM. Furthermore, a series of experimental data for an MTJ, for example, a spin-valve-type MTJ of Ta (5 nm)/Ni79Fe21(25 nm)/lr22Mn78(12 nm)/Co75Fe25(4 nm)/AI(0.8 nm)-oxide/Co75Fe25(4 nm)/Ni79Fe21(20 nm)/Ta (5 nm) in this work, can be self-consistently evaluated and explained using such concise explicit function formulations.

关键词： Magnetic tunnel junction TMR Spin-electron transport Magnon excitation Spin-polarization Magnetotransport

Recent progress in single chip white light-emitting diodes with the InGaN underlying layer

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 445-448页

作者： WANG XiaoLi, WANG XiaoHui, JIA HaiQiang, XING ZhiGang & CHEN Hong beijing national laboratory of condensed matter, institute of physics, chinese academy of sciences, beijing 100080, china beijing national laboratory of condensed matter Institute of Physics Chinese Academy of Sciences Beijing China

Tremendous progress has been achieved in white light-emitting diodes (LEDs). To further improve the quality of white light and simplify the fabrication process, a single chip white-light LED with the InGaN underlying layer (UL) was studied and fabricated. The turn-on voltage of this type of LED was 2.7 V, and the spectrum at a forward bias current of 20 mA was comprised of blue (443 nm) and yellow (563 nm) lights. The intensity ratio of blue to yellow light was almost constant with the in- creasing injection current in a certain scope, most important for the solid state illumination. The useful life test showed the light output level remained at a 90% light output level at the driving current of 40 mA after 300 h, meanwhile, the UV and blue LEDs combined with phosphor reached a 20% value after 144 h within 300 h.

关键词： GaN InGaN white light LED MOCVD