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Stability of proton and maximally symmetric minimal unification model for basic forces and building blocks of matter

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Science china(physics,Mechanics & Astronomy) 2007年第3期50卷 303-310页

作者： WU YueLiang institute of Theoretical physics,{2., Beijing 100080, china 1. institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China

With the hypothesis that all independent degrees of freedom of basic building blocks should be treated equally on the same footing and correlated by a possible maximal symmetry, we arrive at a 4-dimensional space-time unification model. In this model the basic building blocks are Majorana fermions in the spinor repre- sentation of 14-dimensional quantum space-time with a gauge symmetry GM4D = SO(1,3)×SU(32.×U(1)A×SU(3)F. The model leads to new physics including mirror particles of the standard model. It enables us to issue some fundamental questions that include: why our living space-time is 4-dimensional, why parity is not con- served in our world, how the stability of proton is, what the origin of CP violation is and what the dark matter can be.

关键词： gauge symmetry space-time symmetries beyond standard model and unification

EISCAT Observations of Main Ionization Troughs in the High-Latitude Ionosphere

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wuhan University Journal of Natural sciences 2000年第2期5卷 187-193页

作者： LIU Peng 1 ,MA Shu ying 1,2.,K. Schlegel 3 1. College of Electronic Information, wuhan University, wuhan 430072.{2. 2. Ionospheric Observatory, wuhan institute of physics,the chinese academy of sciences, wuhan 430071,{2. 3. Max P wuhan University College of Electronic Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) wuhan University College of Electronic Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) the chinese academy of sciences Ionospheric Observatory Wuhan Institute of Physics Wuhan China (GRID:grid.9227.e) (ISNI:***) Max-Planck Institut fuer Aeronomie Katlenburg-Lindau Germany (GRID:grid.450267.2)

F-region electron density depletions associated with main ionization troughs in the high-latitude ionosphere are studied using EISCAT CP3 data of meridian scanning experiments. The troughs in our observations are found to appear mainly in dusk sector, extending from late afternoon to pre-midnight, with higher occurrence rate during equinox and winter. Simultaneous ion drift velocity inF-region shows that the main trough minimum is mostly located at the equator ward edge of the plasma convection flow, rather than in the region where the largest ion flow are observed.

关键词： high latitude ionosphere main ionization trough plasma convection flow incoherent scatter radar observation

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

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Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2.and Luo Zhexian2.1. institute of Atmospheric physics,{2., Beijing 10002., china 2. Nanjing University of Information sciences & Technology, Nanjing 2.0044, china) institute of Atmospheric physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of Information sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 12.0 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

Structural and microstructural transformations in Bi_2.r_2.a_(1-x)Y_xCu_2._(8+y) system

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chinese Science Bulletin 1997年第3期42卷 192-196页

作者： SONG Chengyu, WEN Shulin and CHE Guangcan1. Shanghai institute of Ceramics, chinese academy of sciences, Shanghai 2.0050,{2. 2. State Key Laboratory of Supercon-ductivity, institute of physics, chinese academy of sciences, Beijing 100080,{2. Shanghai institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2.xSrxCuO4 and YBa2.u3O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity o... 详细信息

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2.xSrxCuO4 and YBa2./sub>Cu3O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity of the superconductive phase. In Bi-2.12.sys-

关键词： Bi2.r2.a1-xYxCu2.y substitution structural transformation.

Meteor radar observation of circulation near mesopause over wuhan

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chinese Science Bulletin 2003年第15期48卷 1634-1638页

作者： XIONG Jiangang, WAN Weixin, NING Baiqi & LIU Libo wuhan institute of {2. and mathematics, chinese academy of sciences, wuhan 430071, china Correspondence should be addressed to Xiong Jiangang (e-mail: xjg@***) wuhan institute of {2. and mathematics Chinese Academy of Sciences Wuhan 430071 China

The wuhan meteor radar is the first all-sky meteor radar in china. The circulation near the mesopause from February to September 2.02.is studied based on the data obtained by the wuhan meteor radar. The zonal wind is usually eastward in winter from 80 to 100 km. The mean zonal wind become westward from March to early of May, when the winter circulation reverses to the summer circulation. But at the meteor heights, the zonal circulation usually becomes eastward after the middle of May. The meridional circulation is always equatorward. The peaks of the meridional wind move downward with the height, and the peak value reaches its maximum of 2. ms-1 in July. Having made a comparison between monthly mean wind and HWM93 model wind, the value of southward wind, the maximal value of eastward wind as well as the reversal height of zonal wind are found to be quite different from each other.

关键词：武汉市气象雷达带状气流数据采集中间层顶

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric sciences, Lanzhou University, Lanzhou 730000, china 2. LASG, {2. of Atmospheric physics, chinese academy of sciences, Beijing 10002., china) College of Atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

STUDY ON THE CONCENTRATION DEPENDENCE OF ORIENTATION OF POLYSTYRENE ON SILVER BY THE SERS TECHNIQUE

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chinese Journal of Polymer Science 2000年第2期18卷 177-180页

作者： Dong-hui Zhang Jin-gui Qin Jing-shu Shen You Wang Wan-jun Liu Department of Chemistry, wuhan University, wuhan 430072.{2. Polymer physics Laboratory, institute of Chemistry, chinese academy of sciences Beijing 100080,{2. wuhan Univ Dept Chem Wuhan 430072 Peoples R China chinese Acad Sci Inst Chem Polymer Phys Lab Beijing 100080 Peoples R China

Polystyrene films were adsorbed onto a silver surface from dichloromethane solutions with concentrations of 0.1 to 12.wt%, and then studied by the surface enhanced Raman technique. A critical concentration for coil in... 详细信息

关键词： surface enhanced Raman scattering (SERS) polystyrene concentration dependence

The lepton flavor violating signal of the extra gauge boson Z′in photon-photon collision at the ILC

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1992-1997页

作者： LIU GuoLi 1,2.1 physics Department,Zhengzhou University,Zhengzhou 450001,china 2.Kavli {2. for Theoretical physics china,chinese academy of sciences,Beijing 100190,china 1. physics Department Zhengzhou University Zhengzhou 450001 China2. Kavli Institute for Theoretical Physics China Chinese Academy of Sciences Beijing 100190 China

The hitherto unconstrained lepton flavor mixings,induced by the new gauge boson Z ,which are the prediction of many new physics models,such as topcolor-assisted technicolor (TC2. models and flavor-universal TC2.models,may lead to the lepton flavor violating productions of τμˉ,τeˉ and μeˉ in photon-photon collision at the proposed International Linear Collider (ILC).Through a comparative analysis of these processes,we find that the better channel to probe the new physics models is the production of τμˉ or τeˉ which occurs at a much higher rate than μeˉ production due to the large mixing angle and the large flavor changing coupling,and may reach the detectable level of the ILC for a large part of the parameter *** the rates predicted by the Standard Model are far below the detectable level,these processes may serve as a sensitive probe for such new physics models.

关键词： new gauge boson Z lepton flavor violating processes photon-photon

Synthesis and Characterization of PEG-like Structures on Nitinol Surface under ECR-cold-plasma

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Journal of wuhan University of Technology(Materials Science) 2005年第1期20卷 33-36页

作者：杨隽 institute of Plasma physics Chinese Academy of Sciences Anhui 230031 China School of Materials Science and Engineering Wuhan Institute of Chemical Tech nologyWuhan 430073China

The synthesis and characterization of PEG-like macromolecular structures on Nit inol surface from tri (ethylene glycol) dimethyl-ether under ECR-cold-plasma conditions were discussed. It was demonstrated that based on high-resolution ES CA, ATR-FTIR and contact angle investigations, the deposited PEG-like layers a re composed mainly of -CH 2.CH 2.O- linkages. These structures have a relati vely low contact angle. Compared to the unmodified surfaces, the plasma-treated Nitinol surfaces are more hydrophilic. Plasma enhanced coatings of PEG-like la yers can prevent Ni ion from releasing, thereby improving the biocompatibility o f Nitinol.

关键词： cold-plasma Nitinol modification PEG-like s tructures