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耦合量子阱中激子凝聚的研究进展

物理 2004年第11期33卷 809-815页

作者：刘承师向涛中国科学院理论物理研究所

近年来 ,半导体量子阱中激子的玻色 -爱因斯坦凝聚研究取得了很大进展 .实验上利用耦合量子阱间接激子中电子和空穴在空间上的分离 ,显著提高了激子的冷却速度和寿命 ,成功地把激子冷却到 1K以下 ,观察到了激子的准凝聚状态 ,并且在强... 详细信息

近年来 ,半导体量子阱中激子的玻色 -爱因斯坦凝聚研究取得了很大进展 .实验上利用耦合量子阱间接激子中电子和空穴在空间上的分离 ,显著提高了激子的冷却速度和寿命 ,成功地把激子冷却到 1K以下 ,观察到了激子的准凝聚状态 ,并且在强激光照射下 ,发现了随光照强度增强而增大的激子发光环和环上形成的有规则斑点图案 ,引起了广泛的兴趣和重视 .理论研究表明 ,发光环的出现是电子和空穴在量子阱中的反常输运行为造成的 ,但环上形成规则斑点的物理机理目前尚不清楚 .文章介绍了这方面的实验背景和形成激子环的物理图像 ,指出了理论研究中存在的问题 ,并对解决问题的方案进行了讨论 .

关键词：激子发光半导体量子阱子环空穴电子凝聚强激光耦合物理机理

Current Status of BSNS Target Station Design

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Current Status of BSNS Target Station Design

Abnormal high pressure in Kuqa foreland thrust belt of Tarim basin: Origin and impacts on hydrocarbon accumulation

第三届散裂中子源多学科应用研讨会

作者： Tianjiao Liang BSNS Target Station Team institute of Physics, chinese academy of sciences, beijing, 100080, china

＜正＞The BSNS target station is composed with following components: tungsten target driven by intense proton beam（1.6Gev, 62.5μA, 25Hz, 100kW）, three moderators (decoupled liquid hydrogen at 20K, decoupled and poi...

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Progress in Natural Science:Materials International 2006年第12期16卷 1307-1314页

作者： ZENG Lianbo~1** and LIU Benming~ 1,2 (1. Key Laboratory of Hydrocarbon Accumulation in china Petroleum University, Ministry of Education, beijing 102249, china 2. The institute of Oil and Gas Exploration and Development, Tarim Oilfield Company, Petrochina Company Limited, Korla 841000, china) Key Laboratory of Hydrocarbon Accumulation in china Petroleum University Ministry of Education Beijing 102249 China The institute of Oil and Gas Exploration and Development Tarim Oilfield Company PetroChina Company Limited Korla 841000 China

Following analyses of the abnormal high pressure distribution characteristics, based on the geological characteristics, tectonic stress field and physical simulation, we investigated the formation mechanisms of abnormal high pressure and its impacts on hydrocarbon accumulation in the Kuqa foreland thrust belt. The abnormal high pressure appears at the bottom of the Paleogene and obviously exists in the Triassic and Jurassic. However, the pressure coefficient in the Triassic and Jurassic is lower than that in the Cretaceous and at the bottom of the Paleogene. Horizontally, the abnormal high pressure distribution is characterized by E-W orientation zoning. The maximum pressure coefficient lies in the Kelasu-Dongqiu-Dina tectonic zones in the center of the Kuqa foreland thrust belt and decreases away from the tectonic zones. The formation of abnormal high pressure was mainly related with the intense tectonic compression in the Early Pleistocene time, and tectonic uplifting, undercompaction and hydrocarbon generation were secondary factors contributing to abnormal high pressure. Under the rapid and intense tectonic compression in the Early Pleistocene, the rock framework firstly undertook 1/4 of the compression stress and the other was borne by the pore fluids. Due to the presence of great seal of gypsum-salt or gypsum-mudstone beds in the Paleogene, the pressure of pore fluids increased rapidly and led to the abnormal high pressure in the Kuqa foreland thrust belt. The abnormal high pressure has important impacts on hydrocarbon accumulation. It is one of the necessary conditions for formation of large oil and gas fields in the Kuqa foreland thrust belt.

关键词： abnormal high pressure formation mechanism oil and gas reservoir Kuqa foreland thrust belt Tarim basin.

Cosmogenic nuclide burial ages and provenance of Late Cenozoic deposits in the Sichuan Basin:Implications for Early Quaternary glaciations in east Tibet

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Cosmogenic nuclide burial ages and provenance of Late Cenozo...

Determination of total selenium in geological samples by HG-AFS? After enrichment with thiol cotton fiber

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Ping Kong~(a,*),Yong Zheng~a,Bihong Fu~a a Key Laboratory of the Earth’s Deep Interior,institute of geology and geophysics,chinese academy of sciences,P.O.Box 9825,beijing 10002.,china

Collision between the Indian and the Eurasian plates since the early Cenozoic produces one of the world’s most remarkable continental escarpments between the Tibetan Plateau and the adjacent Sichuan Basin. Yet Tertiary sediments are rare in the Sichuan Basin;the oldest preserved Late Cenozoic deposits called Dayi conglomerates directly overlie the Cretaceous or Jurassic red *** cosmogenic Be and Al burial dating,we obtain deposition ages of～2.0 Ma and catchment erosion rates of～400 mm/ka for the Dayi *** U-Pb age distributions suggest derivation of these conglomerates from the Songpan-Ganzi flysch,the Pengguan complex and Late Permian and Triassic granite plutons in the headwater regions of the Min Jiang(Jiang,a chinese term,means river).The formation of the poorly-sorted, sub-angular to sub-rounded and tens-centimeter-sized deposits in the western margin of the Sichuan Basin,after long distance transportation,is best explained by glacial activity～2.0 Ma ago in east Tibet.

关键词： Dayi conglomerate Longmen Shan Cosmogenic nuclide Zircon U-Pb age Min Jiang Glaciations

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Acta Geochimica 2006年第S1期 208-209页

作者： Haifeng FAN1,2, Hanjie WEN1, Ruizhong HU1 1 State Key Laboratory of Ore Deposit Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 2 Graduate School of the chinese academy of sciences, beijing 100039, china

Sampling Survey of Disability in 0-6 Year-old Children in china

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Biomedical and Environmental sciences 2006年第5期19卷 380-384页

作者： HUI ZHANG SHAO-HUA BO XI-TAN ZHANG MIN LIU ZHI-XIANG ZHANG XIAO-LING YANG SHU-RONG JI HUA YAN XIU-LI SUI XIN NA SHAO-HUA GUO ZHENG-LAI WU institute of Basic Medical sciences Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College Beijing 100005 China china Disabled Persons＇ Federation Beijing 100006 China academy of Military Medical sciences Beijing 100071 China School of Public Health Health Sciences Center Peking University Beijing 100083 China The First Hospital Peking University Beijing 100034 China institute for Mental Health Peking University Beijing 100083 China china Center for Rehabilitation Research Beijing 100068 China General Hospital Tianjin Medical University Tianjin 300052 China The Third Hospital Affiliated to Tanjin Medical University Tianjin 300203 China

Objective To investigate the current status of disabled children and prevalence of disabilities in children aged 0-6 years and their risk factors, and to provide scientific evidence for making relevant policies for disabled children. Metlmds In a community-based cross-sectional study, multi-phase, stratified, unequal proportional and cluster sampling was adopted to survey 60 124 children aged 0-6 years. All the investigated children were screened for disabilities, and those with positive screening tests were further diagnosed by various specialties. Results A total of 819 children were diagnosed as disabled with an overall prevalence of 1,362%, 0.155% for hearing disability, 0.160% for visual disability, 0.931% for intelligent disability, 0.424% for limb disability, and 0.101% for mental disability. Prevalence of disability in children was higher in rural areas, and in families with two or more children, low educational level or in divorced families. Conclusion The prevalence of disability can be reduced by economic development, improvement of health care and quality of population, as well as harmonious familial relationship, early prevention of disability, and preschool education for disabled children.

关键词： Children Disability Prevalence Risk factor

CONSTITUTIVE POTENTIAL FOR DUCTILE DAMAGED MATERIAL AND VOID GROWTH RATE

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Acta Mechanica Sinica 1989年第2期5卷 125-135页

作者： Wang Tzuchiang (institute of Mechanics,Academia Sinica,beijing,china) institute of Mechanics Academia Sinica Beijing China

In this paper a general formula for plastic potential including isotropic ductile damage has been present ed on the basis of the thermodynamics for irreversible process and internal variable the- *** this formula the mass conservation law is satisfied and it also contains a series of unknow coefficients which are the function of macro equivalent stress and the average micro equivalent stress and an unknown function which is the function of two generalized forces. The approximate yield surface equation for isotropically damaged materials is *** this equation the void growth rate is calculated for nonlinear material containing *** present re- sults are in good agreement with the numerical results given by the cell model.

关键词： constitutive potential damaged materials void growth thermodynamics irreversible process

A thermal-mechanical constitutive model for b-HMX single crystal and cohesive interface under dynamic high pressure loading

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 218-226页

作者： WU YanQing & HUANG FengLei State Key Laboratory of Explosion Science and Technology,beijing institute of Technology,beijing 100081,china State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing China

Due to the significant thermal-mechanical effects during hot spot formation in PBX explosives,a thermodynamic constitutive model has been constructed for HMX anisotropic single crystal subjected to dynamic impact loading. The crystal plasticity model based on dislocation dynamics theory was employed to describe the anisotropic plastic behavior along the preferential slip systems. A modified equation of state (EOS) was introduced into the constitutive equations through the decomposing stress tensor and the nonlinear elasticity for materials was taken into account. The one-dimensional strain impact simulations for HMX single crystal and quasi-bicrystal were performed respectively,in which the cohesive elements were inserted over the interface areas for the latter. The predicted particle velocities for the single crystal sample agreed well with the experimental results in the literature. Furthermore,the effects of crystal orientations,interface,misorientations on localized strain,stress and temperature distributions were predicted and discussed.

关键词： energetic single crystal dynamic high pressure crystal plasticity thermodynamics interfacial model

How Subordinates Reciprocate Supervisor’s Trust:A Cross-level Model

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How Subordinates Reciprocate Supervisor’s Trust:A Cross-lev...