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Studies on BEPC upgrade from pretzel to double-ring

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2084-2089页

作者： ZHANG Chuang institute of High Energy Physics,chinese academy of {3.,beijing 100049,china 1. institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Physics opportunity in the charm and τ energy region calls for higher luminosity of the beijing Electron-Positron Collider (BEPC).The BEPC has experienced continuous improvement since its completion in ***,as a major upgrading project of the BEPC,aims at enhancing its luminosity of factor 3.–100,following the principle of "one machine,two purposes" as adopted in BEPC,so that both high energy physics and synchrotron radiation experiments can be carried out with *** the BEPC to BEPCII,the double-ring scheme with multi-bunch e +-e-collision in the large crossing angle was studied in comparison with the single-ring pretzel *** the dedicated synchrotron radiation operation,artful "bridges" are designed to connect two halves of the outer ring in both the southern and the northern crossing *** paper reviews the studies on the BEPC upgrade from pretzel to double-ring structure of BEPCII.

关键词： collider storage ring high energy physics synchrotron radiation

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass up to 24 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 Matter Physics, institute of Physics, chinese academy of sciences, {3. 100080, china 3. BSRF, institute of High Energy Physics, chinese academy of sciences, {3. 10003., china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) is investigated at room temperature up to 24 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.

Modeling on runoff concentration caused by rainfall on hillslopes and application in Maoping slope

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Progress in Natural Science:Materials International 2006年第10期16卷 1056-1065页

作者： LIU Qingquan and LI Jiachun (institute of Mechanics, chinese academy of sciences, beijing 100080,{3.) [a]chinese academy of sciences' Institute of Mechanics' Beijing China

Based on the fact that the concentration flowlines of overland flow depend on the surface landform of hillslope, a kinematic wave model was developed for simulating runoff generation and flow concentration caused by rainfall on hillslopes. The model-simulated results agree well with the experimental observations. Applying the model to the practical case of Maoping slope, we obtained the characteristics of runoff generation and infiltration on the slope. Especially, the simulated results adequately reflected the confluent pattern of surface runoff, which offers a scientific foundation for designing the drainage engineering on the Maoping slope.

关键词： complex hillslope rainfall infiltration overland flow runoff concentration Maoping slope.

Some problems on the studies of the late Pleistocene human evolution and formation of modern human populations

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Progress in Natural Science:Materials International 2006年第12期16卷 1233-1241页

作者： LIU Wu(institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, beijing 100044,{3.) [a]institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China

For the past two decades, studies and debates on the modern human origins around the world have attracted attentions to the late Pleistocene human evolution and formation of modern human populations, and some controversial hypotheses and problems have been proposed. In the present paper, some problems on the late Pleistocene human evolution, and the formation and differentiations of modern human populations in china are studied with a brief description and comments on the research advances in this field.

关键词： late Pleistocene human evolution formation and differentiation of modern human population paleoanthropology.

Effective solutions to a global 3. visual system in networking environments

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Science china Earth sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2, ZHANG Yan3. YANG Chongjun2, LIU Suhong1, REN Yingchao2, RUI Xiaoping2 & LIU Donglin2 1. State Key Laboratory of Remote Sensing sciences, School of Geography and Remote Sensing, beijing Normal University, beijing 100875,{3. 2. State Key Laboratory of Remote Sensing sciences, institute of Remote Sensing Applications, chinese academy of sciences, beijing 101001,{3. 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 101001,{3. 1. State Key Laboratory of Remote Sensing sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. chinese academy of sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3. visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

Geochemical characteristics of rare earth elements in Wuhan section of the Yangtze River

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Journal of Environmental sciences 1995年第1期7卷 44-51页

作者： Wang Lijun Zhang Shen Zhang Chaosheng(institute of Geography,chinese academy of {3.,beijing 100101,china)Li Xiuxia(institute of High Energy Physics,chinese academy of {3.,beijing 100080,china) Inst of Geog Chinese Academy of Sciences Beijing China China

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关键词： geochemical characteristics rare earth elements Yangtze River

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth sciences and Natural Resources, china University of Geosciences, {3. 100083. china 2. Faculty of Earth sciences, china University of Geosciences, Wuhan 43.074, china 3. {3. SHRIMP Center, institute of geology, chinese {{13. of Geological sciences, {3. 10003., china 1. Faculty of Earth sciences and Natural Resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China 3. beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

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 Physics, chinese academy of sciences, beijing 10002.,{3. 2. Department of Atmospheric Science, Yunnan University, Kunming 650091,{3. 3. Graduate University of the chinese academy of sciences, beijing 100049,{3. 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the chinese academy of sciences Beijing 100049 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.

On the contact width in generalized plain strain JKR model for isotropic solids

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Acta Mechanica Sinica 2009年第4期25卷 491-497页

作者： Cong Yan Shaohua Chen LNM, institute of Mechanics, chinese academy of sciences,100190 beijing.{3. LNM Institute of Mechanics Chinese Academy of Sciences 100190 Beijing China

Adhesive contact model between an elastic cylinder and an elastic half space is studied in the present paper, in which an external pulling force is acted on the above cylinder with an arbitrary direction and the contact width is assumed to be asymmetric with respect to the structure. Solutions to the asymmetric model are obtained and the effect of the asymmetric contact width on the whole pulling process is mainly discussed. It is found that the smaller the absolute value of Dundurs＇ parameter 13.or the larger the pulling angle O, the more reasonable the symmetric model would be to approximate the asymmetric one.

关键词： Contact mechanics Generalized JKRmodel Asymmetric contact width Oscillatory solution Non-oscillatory solution