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chinese science Bulletin 2000年第15期45卷 1345-1351页

作者： WANG Songshan, GE Ningjie, SANG Haiqing & QIU Ji1. Institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002., china 2. Department of Earth and {2. {3., University of {3. and Technology of china, Hefei 2.3}02., china Correspondence should be addressed to Wang Songshan Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Earth and space science University of Science and Technology of China Hefei China

The Ar-Ar dating of phengite and omphacite in ultrahigh-pressure (UHP) eclogite of Bixiling and Hengchong in the South Dabie Terrain shows that the content range of excess argon is as high as (0.4-1.3.×10 8 mol· g 1. The genesis of the excess argon is discussed. The Ar-Ar age spectra of omphacite could not support the opinion that the UHP metamorphism occurred in Caledon epoch and pre-Caledon epoch.

关键词： South Dabie Terrain ultrahigh-pressure metamorphics phengite omphacite excess argon.

Lunar surface dielectric constant,regolith thickness, and ~3.e abundance distributions retrieved from the microwave brightness temperatures of CE-1 Lunar Microwave Sounder

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science china Earth {2. 2010年第9期53卷 1365-1378页

作者： WANG ZhenZhan1, LI Yun1,2. JIANG JingShan1 & LI DiHui1 1 National Microwave Remote Sensing Laboratory, Center for space science and Applied Research,{2., Beijing 100190,{3. 2.Graduate University of{2., Beijing 100049,{3. 1. National Microwave Remote Sensing Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3.e content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43. of them are bigger than 5.0 m. The content of 3.e evaluated by retrieved regolith thickness is about 1.03.million tons.

关键词： CE-1 Lunar Microwave Sounder (CELMS) lunar regolith dielectric constant lunar regolith thickness 3.e retrieval

Quantitative analysis of soil pores under natural vegetation successions on the Loess Plateau

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science china Earth {2. 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2.& WU JinShui3.1 State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture & Forestry University,Yangling 712.00,china 2.Graduate University of{2.,Beijing 100049,china 3.Institute of Subtropical Agriculture,{3. academy of sciences,Changsha 41012.,china 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling 712100 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 China

Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(CT) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the Loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(P<0.001).Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

关键词： Computed Tomography Loess Plateau natural vegetation succession soil pore soil organic matter

space science & Technology in{2.:A Roadmap to 2.50

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空间科学学报 2010年第5期30卷 385-387页

作者： Research Group on space science & Technology of the{2. Research Group on space science & Technology of the{2.

In October 2.07, the chinese academy of sciences (CAS) initiated a project entitled 'Roadmapfor Strategic Research in Key Fields of science and Technology in{2. through 2.50'. The project

关键词：空间科学中国科学院科学技术中科院路线图路甬祥

Improvement of the SLP simulation in the coupled AGCM-ocean surface wave model

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chinese science Bulletin 2005年第20期50卷 2397-2400页

作者： YU Weidong1, 2. 3. LI Zhaoxin4 & YUAN Yeli3.1. Institute of Oceanology,{2., Qingdao 2.6071, china 2. Graduate School of{2., Beijing 100049, china 3. Laboratory of Marine science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061, china 4. LMD/CNRS, Univ. Paris 6, Paris, France Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of chinese academy of sciences Beijing 100049 China Laboratory of Marine science and Numerical Modeling First Institute of Oceanography State Oceanic Administration Qingdao 266061 China LMD/CNRS Univ. Paris 6 Paris France

The coupled atmosphere-ocean general circulation models (CGCM) are nowbecoming the indispensable tools for the climate study. However, most models still suffer fromunrealistic simulations. One problem is the troublesome climate drift. It may come from someunresolved aspects. One possibility is the poor air-sea surface flux description now adopted inCGCM. The commonly used solution for this problem is the so-called flux correction. To deal with it,Hasslemann proposed an alternative solution of prospect. That is to incorporate the ocean surfacewave model into this coupled GCM system so as to establish a coupled atmosphere-wave-ocean *** necessity is clearly seen from the recent field experiment that air-sea momentum flux dependsstrongly on the sea state. So the explicit calculation of the air-sea flux with the aid of the oceansurface wave model is highly desired. Theoretical progress has provided feasibility to such ideaand experiments have been conducted. Recent work also reveals that coupling ocean surface wave modelwith oceanic general circulation model can result in much better reproduction of the upper oceanthermal structure. This further strengthens our belief in the final realization of the coupledatmosphere-wave-ocean modeling system.

关键词：大气海洋循环模式气象学 SLP模拟

A CLASS OF TWO-STEP TVD MACCORMACK TYPE NUMERICAL SCHEME FOR MHD EQUATIONS

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空间科学学报 2003年第6期23卷 401-412页

作者： FENG Xueshang WEI Fengsi ZHONG Dingkun(Center for space science and Applied Research, The{2., Beijing {3.) Center for space science and Applied Research The Chinese Academy of Sciences 北京 100080

In this paper, a new numerical scheme of Total Variation Diminishing (TVD) MacCormack type for MagnetoHydroDynamic (MHD) equations is proposed by taking into account of the characteristics such as convergence, stability, resolution. This new scheme is established by solving the MHD equations with a TVD modified MacCormack scheme for the purpose of developing a scheme of quick convergence as well as of TVD property. To show the validation, simplicity and practicability of the scheme for modelling MHD problems, a self-similar Cauchy problem with the discontinuous initial data consisting of constant states, and the collision of two fast MHD shocks, and two-dimensional Orszag and Tang's MHD vortex problem are discussed with the numerical results conforming to the existing results obtained by the Roe type TVD, the high-order Godunov scheme,and Weighted Essentially Non-Oscillatory (WENO) scheme. The numerical tests show that this two-step TVD MacCormack numerical scheme for MHD system is of robust operation in the presence of very strong waves, thin shock fronts, thin contact and slip surface discontinuities.

关键词：磁液体力学方程两步TVD-MacCormack图解法收敛性稳定性数值模拟

Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： LIU QingHui1, CHEN Ming1, XIONG WeiMing2. QIAN ZhiHan1, LI JinLing1, HAO WangHong1,4, WANG GuangLi1, ZHENG WeiMin1, GUAN Di3. ZHU RenJie1, WANG WeiHua1, ZHANG XiuZhong1, JIANG DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 2.003., china 2.Center for space {3. and Applied Research, chinese academy of sciences, Beijing 100190, china 3.Lunar Explorer Engineering general Department, chinese academy of sciences, Beijing 100012. china 4 Beijing Institute of Tracking and Telecommunications Technology, Beijing 100094, china 1. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China4. Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China3. Lunar Explorer Engineering General Department Chinese Academy of Sciences Beijing 100012 China

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover

Numerical study of successive CMEs during November 4―5, 1998

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science china(Technological {2.) 2008年第10期51卷 1600-1610页

作者： ZHOU YuFen & FENG XueShang SIGMA Weather Group, State Key Laboratory for space Weather, Center for space {2. and Applied Research,{3., Beijing 100190, china 1. SIGMA Weather Group State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China

We present the solar-terrestrial transit process of three successive coronal mass ejections (CMEs) of November 4―5, 1998 originating from active region 83.5 by using a time-dependent three-dimensional magnetohydrodynamics (MHD) simula-tion. These CMEs interacted with each other while they were propagating in inter-planetary space and finally formed a "complex ejecta". A newly developed SIP-CESE MHD model was applied to solve MHD equations numerically. The quiet solar wind was started from Parker-like 1D solar wind solution and the magnetic field map was calculated from the solar photospheric magnetic field data. In our simulation, the ejections were initiated using pulse in the real active region 83.5. The interplanetary disturbance parameters, such as speed, direction and angular size of the expanding CME, were determined from the SOHO/LASCO data with the cone-model. We discussed the three-dimensional aspects of the propagation, in-teraction and merging of the three ejections. The simulated interplanetary shocks were compared with the nearby-Earth measurement. The results showed that our simulation could reproduce and explain some of the general features observed by satellite for the "complex ejecta".

关键词： complex ejecta three-dimensional MHD simulation SIP-CESE MHD model

A template of rat brain based on fMRI T2. imaging

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Progress in Natural science:Materials International 2005年第6期15卷 502-506页

作者： HU Zhenghui1, WU Yigen2. WANG Xiaochuan3. WANG Jianzhi3. CHEN Feiyan1 and TANG Xiaowei1*(1. Department of Physics and Bio-X Laboratory, Zhejiang University, Hangzhou 3.002., china 2. Institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, chinese academy of sciences,Beijing 10003., china 3. Department of Pathophysiology, Tongji Medical College, Huazhong University of {3. and Technology, Wuhan 43.03., china) Department of Physics and Bio-X Laboratory Zhejiang University Hangzhou 310027 China Institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of Sciences Beijing 100039 China Department of Pathophysiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

The development of functional magnetic resonance imaging (fMRI) technology has made it possible to carry out functional brain imaging experiments in small animals. Usually, group data is required to form the assessment of population, which can not only increase the sensitivity of the overall experiment, but also allow the generalization of the conclusion to the whole population. In order to average the signals of functional brain images from different subjects, it is necessary to put all the mapping images into the same standard space (template image). However, up to now, most animal brain templates remain unavailable and it must be done by ourselves. In this study, a template image based on the brains of eight male Wistar rats is obtained, and it is successfully used in our present Alzheimer disease (AD)-like rat model studies as template for spatially normalizing images to the same stereotaxical space. The fMRI results processed with statistical parametric mapping (SPM99) software are in agreement with the results from immunohistochemical experiment, which proves that this method is universally applicable to the pathologic models of other small animals and to human brain lesion studies.

关键词： fMRI animal model atlas template normalization T*2.

The Prediction of Maximum Amplitudes of Solar Cycles and the Maximum Amplitude of Solar Cycle 2.

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 557-562页

作者： Jia-Long Wang, Jian-Cun Gong, Si-Qing Liu, Gui-Ming Le and Jing-Lan Sun1 National Astronomical Observatories, chinese academy of sciences, Beijing 100012. Center for space {2. and Applied Research, chinese academy of sciences, Beijing 100080 Center for space science and Applied Research Chinese Academy of Sciences Beijing 100080

We present a brief review of predictions of solar cycle maximum amplitude with a lead time of 2.years or more. It is pointed out that a precise prediction of the maximum amplitude with such a lead-time is still an open question despite progress made since the 1960s. A method of prediction using statistical characteristics of solar cycles is developed: the solar,cycles are divided into two groups, a high rising velocity (HRV) group and a low rising velocity (LRV) group, depending on the rising velocity in the ascending phase for a given duration of the ascending phase. The amplitude of Solar Cycle 2. can be predicted after the start of the cycle using the formula derived in this paper. Now, about 5 years before the start of the cycle, we can make a preliminary prediction of 83.2.119.4 for its maximum amplitude.

关键词： Sun : sunspots Sun : activity