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Collision dynamics of He@C_(60)+He@C_(60) at low energies

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science china(physics,Mechanics & Astronomy) 2008年第7期51卷 765-772页

作者： ZHAO Qiang1,2, ZHANG FengShou1,2,3.& ZHOU HongYu1,2 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear physics, beijing Normal University, beijing 100875, {3. 2 beijing Radiation center, beijing 100875, {3. 3.center of theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 73.000, {3. Key Laboratory of Beam Technology and Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation center Beijing China center of theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

A semi-empirical molecular dynamics model is developed. The central collisions of C60+C60 and He@C60+He@C60 at different incident energies are investigated based on this model. It is found that the dimer structures have been produced at proper incident energies and these fullerene dimers could be formed by a self-assembly of C60 fullerene and He@C60. The He atom has a significant effect at higher incident energy and this embedded He atom can enhance the stability of the dimer structure.

关键词： C60 He@C60 collision molecular dynamics

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, {3. 100080, china 2. School of Life science and Technology, {3. Institute of Technology, {3. 100081, china 3. College of Chemistry and Molecular Engineering, Peking University, {3. 100080, china 4. center for Condensed Matter physics, Institute of physics, chinese academy of sciences, {3. 100080, china 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 Matter 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 3. 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.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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science china Earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3. ZHANG RenHe2, SUN ShuFen1, BIAN LinGen2, XIAO CunDe4,2 & ZHANG TingJun5 1 Institute of Atmospheric physics, chinese academy of {3.s, beijing 100029, china 2 chinese academy of Meteorological {3.s, beijing 100081, china 3.Graduate University of chinese academy of {3.s, beijing 100049, china 4 Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of {3.s, Lanzhou 73.000, china 5 The National Snow and Ice Data center, University of Colorado, Boulder, CO 803.9-0449, USA Institute of Atmospheric physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China chinese academy of Meteorological sciences Beijing China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China The National Snow and Ice Data center University of Colorado Boulder USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3. 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2) the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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science china(physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2, CHEN ZhengHao3.& ZHANG XiaoZhong4,5 1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, Institute of Low Energy Nuclear physics, beijing Normal University, beijing 100875, {3. 2 beijing Radiation center, beijing 100875, {3. 3.Laboratory of Optical physics, Institute of physics, chinese academy of sciences, beijing 100080, {3. 4 Key Laboratory of Advanced Materials of the Ministry of Education, Department of Materials science and Engineering, Tsinghua University, beijing 100084, {3. 5 beijing National center for Electron Microscopy, Tsinghua University, beijing 100084, {3. Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation center Beijing China Laboratory of Optical physics Institute of Physics Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China beijing National center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-xTexO3.δ (x=0.1, 0.2, 0.3. were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3. ions are partly converted into Mn2+ and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2+, Mn3. and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3. is much larger or less than the sum of Mn2+ and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3. is close to the sum of Mn2+ and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, Institute of Atmospheric physics, chinese academy of {3.s, beijing 100029, china Graduate School of chinese academy of {3.s, beijing 100049, china National Climate center, Laboratory of Climate Studies, china Meteorological Administration, beijing 100081, china) LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of chinese academy of sciences Beijing 100049 China National Climate center Laboratory of Climatic Studies China Meterological Administration Beijing 100081 China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

Charmed Baryon in Diquark Model

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原子核物理评论 2009年第S1期26卷 190-193页

作者： WANG Qing-wu1,3. ZHANG Peng-ming1,2(1 Institute of Modern physics, chinese academy of {3.s, Lanzhou 73.000, china 2 center of theoretical Nuclear physics, National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 73.000, china 3.Graduate School of chinese academy of {3.s, beijing 100049, china) Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Graduate School of chinese academy of sciences Beijing 100049China Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China center of theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China

A diquark model is used to investigate single-charmed baryons. In this model,baryon is composed of two diquarks and an antiquark. Masses of lowest lying states with JP=1/2± are obtained. Baryons in our results are as heavy as other theoretic predictions and we suggest that the five-quark components should be considered in any three-quark model for studying the charmed baryons.

关键词： charm diquark pentaquark

Global analysis theory of climate system and its applications

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chinese science Bulletin 2003年第10期48卷 1034-1039页

作者： LI Jianping1,2 & CHOU Jifan2,3.1. LASG, Institute of Atmospheric physics, chinese academy of {3.s, beijing 100029, china 2. Department of Atmospheric {3.s, Lanzhou University, Lanzhou 73.000, china 3. Training center for china Meteorological Administration, beijing 100081, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences Lanzhou University Lanzhou 730000 China Training center for china Meteorological Administration Beijing 100081 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Sea surface temperature east of Australia:A predictor of tropical cyclone frequency over the western North Pacific?

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chinese science Bulletin 2011年第2期56卷 196-201页

作者： ZHOU BoTao 1,2 & CUI Xuan 3.1 National Climate center,china Meteorological Administration,beijing 100081,china 2 Nansen-Zhu International Research center,Institute of Atmospheric physics,chinese academy of sciences,beijing 100029,china 3.National Meteorological center,china Meteorological Administration,beijing 100081,china National Climate center China Meteorological Administration Beijing China Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China National Meteorological center China Meteorological Administration Beijing China

The relationship between sea surface temperature (SST) east of Australia and tropical cyclone frequency over the western North Pacific (WNPTCF) is analyzed by use of observation *** WNPTCF from June to October is correlated negatively to spring SST east of *** the spring SST is in the positive phase,a cyclonic circulation anomaly in the upper troposphere and an anticyclonic circulation anomaly in the lower troposphere prevail over the western North Pacific from June to October,concurrent with an anomalous atmospheric subsidence and an enlarged vertical zonal wind *** conditions are unfavorable for tropical cyclone genesis,and thus WNPTCF *** negative phase of the spring SST east of Australia leads to more tropical cyclones over the western North *** spring SST east of Australia may give rise to simultaneous change in tropical atmospheric circulation via the teleconnection wave train,and then subsequently affect atmospheric circulation variation over the western North Pacific.

关键词：热带气旋北太平洋澳大利亚西部海面温度热带大气环流预测频率

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3.LIU XiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change Research center,chinese academy of {3.s,beijing 100029,china 2 Nansen-Zhu International Research Centre,Institute of Atmospheric physics,chinese academy of {3.s,beijing 100029,china 3.Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,chinese academy of {3.s,beijing 100029,china 4 State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,chinese academy of {3.s,Xi’an 710075,china 5 Graduate University of chinese academy of {3.s,beijing 100049,china Climate Change Research center Chinese Academy of Sciences Beijing China Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of sciences Beijing China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模