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Zonal propagation of kinetic energy and convection in the South china Sea and Indian monsoon regions in boreal summer

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Science china Earth Sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2 ,HE Jinhai 2 ,TAO Shiyan 3.& JIN Zuhui 3.1.Chinese Academy of Meteorological Sciences,Beijing 100081,china 2.Nanjing institute of Meteorology,Nanjing 210044,china 3.institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,china 1. Chinese Academy of Meteorological Sciences 100081 Beijing China 2. Nanjing institute of Meteorology 210044 Nanjing China 3. Chinese Academy of Sciences Institute of Atmospheric Physics 100029 Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South china Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

Effects of cosmological constant on motion of UHECR particles

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe institute of High energy Physics, Chinese Academy of Sciences, Beijing 10003., china Graduate School of Chinese Academy of Sciences, Beijing 10003., china institute of High energy Physics Chinese Academy of Sciences Beijing 100039 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

Analysis of leakage current in GaAs micro-solar cell arrays

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Science china(Technological Sciences) 2010年第5期53卷 1240-1246页

作者： WANG YanShuo1,CHEN NuoFu1,2,3.ZHANG XingWang1,BAI YiMing1,WANG Yu1,HUANG TianMao1,ZHANG Han1 & SHI HuiWei1 1 Key Laboratory of Semiconductor Materials Science,institute of Semiconductors,Chinese Academy of Sciences,PO Box 912,Beijing 100083.china 2 School of Renewable energy Engineering,North china Electric Power University,Beijing 102206,china 3.National Laboratory of Micro-Gravity,institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,china 1. Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China2. School of Renewable Energy Engineering North China Electric Power University Beijing 102206 China3. National Laboratory of Micro-Gravity Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The output characteristics of micro-solar cell arrays are analyzed on the basis of a modified model in which the shunt resistance between cell lines results in current *** modification mainly consists of adding a shunt resistor network to the traditional *** obtained results agree well with the reported experimental *** calculation results demonstrate that leakage current in substrate affects seriously the performance of GaAs micro-solar cell *** performance of arrays can be improved by reducing the number of cells per *** addition,at a certain level of integration,an appropriate space occupancy rate of the single cell is recommended for ensuring high open circuit voltages,and it is more appropriate to set the rates at 80%-90% through the calculation.

关键词： micro-solar cell MEMS(micro-electromechanical systems) leakage current

Analyses of p-^(11)B,p-^(11)C and d-^(11)C Reactions

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Chinese journal of nuclear physics 1995年第1期17卷 60-66页

作者： Shen Qing-biao Zhang Jing-shang Han Yin-lu Bai Xi-xiang (china institute of atomic {3.,P.O.Box 275(41),Beijing 102.13. 中国原子能科学院北京

Aiming at the production of 11C radioactive beam,various nuclear data ofp+11B reaction at incident proton energies spanning 1-25 MeV were obtained by calcu-lation with quasiquantum multistep direct （QMSD） theory and Hauser-Feshbach （HF）*** calculations basically agree with the experimental *** angular distri-butions in lab frame of 11C produced in the reversed geometry reaction 1H(11B,11C)nwere *** cross sections of p+11C and d+11C reactions induced by 11C beamwere also *** results show that the experimental measurement for 11C+d re-action is more feasible than for 11C+p reaction at HI-13.tandem accelerator.

关键词： 11C Radioactive beam Analyses

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3. Mai-Li LIU3. Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary Laboratory, Zhejiang University, Hangzhou 3.0027,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 43.03., china 2institute of High {3. Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of Sciences, P.O. Box 918, Beijing 10003., china 3.uhan institute of Physics and Mathematics, State Key Laboratory of Magnetic Resonance and atomic and Molecular Physics, Chinese Academy of Sciences, Wuhan 43.071, china Department of Physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan institute of Physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China institute of High energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2* signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser3.6/Ser404 and Ser199/Ser202 was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24 h after isoproterenol injection. (3. A sensitivity threshold of resting T2* signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 3..62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

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Science china(Technological Sciences) 2009年第12期52卷 3514-3520页

作者： SUN Jian 1,2 &SHI MingHeng 1 1School of energy and Environment,Southeast University,Nanjing 210096,china 2Department of Thermal energy Engineering,Jingdezhen Ceramic {3.,Jingdezhen 3.3.01,china 1. School of energy and Environment Southeast University Nanjing 210096 China 2. Department of Thermal energy Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China

Hybrid photovoltaic/thermal(PV/T)system with solar concentrator is an effective way to improve solar energy conversion *** this work,a single-pass PV/T air system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing *** on energy balance,the heat transfer models of all main components in this system are *** effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed. The results show that the solar radiation intensity can be higher than 1200 W/m 2 at most area of the cell *** temperature of the air and cell surface increases along the length of the *** the system efficiency of the CPC is higher than that of the system without the *** thermal efficiency, exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the *** increasing packing fraction the electrical efficiency increases,but the thermal efficiency *** exergy efficiency increases slightly with the packing fraction *** data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

关键词： photovoltaic/thermal system CPC exergy efficiency thermal and electricity performance optical

Simulating　Experimental　Investigation　on　the　Safety　of　Nuclear　Heating　Reactor　in　Loss－of－Coolant　Accidents

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Journal of Thermal Science 1996年第4期5卷 285-291页

作者： Zhanjie Xu(institute of Nuclear energy Technology, Tsinghua University, Beijing, 100084, china) institute of Nuclear energy Technology Tsinghua University Beijing China

The 5MW low temperature nuclear heating reactor (NHR-5) is a new and advanced type of nuclear reactor developed by institute of Nuclear energy Technology (INET) of Tsinghua University of china in 1989. Its main loop is a thermal-hydraulic system with natural circulation. This paper studies the safety of NHR under the condition of loss-of-coolant accidents (LOCAs) by means of simulant experiments. First, the background and necessity of the experiments are presented, then the experimental system, including the thermal-hydraulic system and the data collection system, and similarity criteria are introduced. UP to now, the discharge experiments with the residual heating power (20% rated heating power) have been carried out on the experimental system. The system parameters including circulation flow rate, system pressure, system temperature, void fraction, discharge mass and so on have been recorded and analyzed. Based on the results of the experiments, the conclusions are shown as folios: on the whole, the reactor is safe under the condition of LOCAs, but the thermal vacillations resulting from the vibration of the circulation flow rate are disadvantageous to the internal parts of the reactor core.

关键词： nuclear heating reactor natural circulation LOCA safety.

ON THE SPECTRUM OF THE LINEAR TRANSPORT OPERATOR IN L^P SPACE

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Systems Science and Mathematical Sciences 1999年第4期12卷 289-291页

作者： WANG Wenlong(Department of Mathematics, Shangrao Teacher’s College, Jiangxi 3.4001, china)YANG Mingzhu(china institute of {3. energy, Beijing 102.13. china) 上饶师范专科学校数学系江西上饶 334001 中国原子能科学院北京 102413

The spectrum of the transport operator A in a nonhomogeneous slab withcontinuous energy is discussed in consideration of anisotropic scattering and fission. Weshow the relative compactness of the perturbation K = A - B, investigate the spectrumof A, especially obtain the essential spectrum and the asymptotic point spectrum in L1space which is the most natural space for the transport theory.

关键词： Transport operator compact operator weakly compact operator essentialspectrum asymptotic point spectrum.

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2, DU Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2, 4 1. State Key Laboratory for Surface Physics, institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 2. Laboratory of Electron Microscopy, institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 3. College of Physics and Engineering, Qufu Normal University, Qufu 273.65, china 4. Beijing University of Technology, Beijing 100022, china 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. College of Physics and Engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. Beijing University of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.