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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

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 100029, {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

Recent beijing Spectroscopy (BES) results

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Science china(Physics,Mechanics & Astronomy) 2008年第6期51卷 567-576页

作者： LI WeiGuo institute of High Energy Physics, chinese academy of sciences, beijing 100049, {3. 1. institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Recent experimental results from beijing Spectroscopy (BES) are reviewed, including the hadron spectroscopy from J/ψ decays, and a number of new states are found or confirmed, including σ, κ, X(183.), ωφ threshold enhancement in J/ψ→γωφ, a broad resonance in J/ψ→K + K ? π 0, decay studies of ψ(2S) and χ CJ , as well as the results of ψ(3.70) non-D $ \bar D $ decays. The current status of BEPCII/BESIII, the major upgrade of BEPC/BESII, is also reported.

关键词： beijing Spectroscopy hadron spectroscopy charm physics BEPCII

Two possible mechanisms for vortex self-organization

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Science china Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. chinese academy of Meteorological sciences, {3. 100081, china 2. Department of Space Information Science, Nanjing University of Information Science and Technology, Nanjing 210044, china 3. institute of Atmospheric Physics, chinese academy of sciences, {3. 100029, china 2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. chinese academy of Meteorological sciences Beijing 100081 China 3. institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Software Engineering Technology for the 21^(st) Century

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Wuhan University Journal of Natural sciences 2001年第Z1期6卷 152-158页

作者： Cheng Hu institute of Software, chinese academy of sciences beijing 100080, {3. institute of Software Chinese Academy of Sciences Beijing 100080 China

In this paper we will discuss the software engineering technology for the 21 st century. First we review development over the last half century, overview application requirement and environment, accept a challenge. Then we outline following software engineering techniques: 1) Process;2) Analysis;3. Design;4) UML;5) Component;6) Java +XML;7) Integrated;8) Quality(ISO9000&CMM).

关键词： software engineering object oriented component Java UML CMM ISO9000

An optimization approach to the similarity criteria of flows and its application

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Progress in Natural Science:Materials International 2006年第3期16卷 241-247页

作者： ZHOU Jifu and LI Jiachun (institute of Mechanics, chinese academy of sciences, beijing 100080, {3.) [a]institute of Mechanics Chinese Academy of Science Beijing China

In the present paper, we propose an optimization approach to investigate the similarity criteria of complex flows. With this approach, we may identify the dominant dimensionless variables governing complex flows by numerical sensitivity analysis. Firstly, we define the sensitivity factor and examine its dependence on the dimensionless variables. Then, we apply this approach to study the similarity criteria of porous media flow in a presumed oil reservoir. The similarity principle obtained from the numerical sensitivity analysis is in agreement with the theoretical law, thus demonstrating the feasibility of the proposed optimization approach. Further explanation is given by analyzing the deviation of pressure distribution in a model from its prototype. In addition, we examine the effects of flow parameter variation on the sensitivity factors and find that the dominant dimensionless variables may change from different sets of parameters.

关键词： similarity optimization sensitivity analysis complex flows model.

Phosphorus availability in two soils amended with poultry litter

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Journal of Environmental sciences 1996年第4期8卷 483-490页

作者： Han Xingguo (institute of botany,chinese {3. of sciences,beijing 100093.china)Duane C.Wolf (Department of Agronomy,University of Arkansas,Fayetteville, AR 72701,USA) institute of botany Chinese Academy of Sciences Beijing 100093 China Department of Agronomy University of Arkansas Fayetteville AR 72701 United States

Understanding P transformation in soils amended with poultry litter is important if water quality is to be *** objectives were to determine the influence of method of litter application and temperature on P availability. Poultry litter containing 20. 8g P/kg (dry weight) was either surface-applied or incorporated into Captina (fine-silty, siliceous, mesic Typic Fragiudult) and Nixa (loamy-skeletal,siliceous,Glossic Fragiudult) silt loams at rates of 0 or 10g/kg and incubated at 20℃ or 3.℃ at a water potential of -40 kpa. Water soluble and available P (0.03.mol/L NH4F+0. 025mol/L HCl extraction) were determined during a 60d laboratory study. Results indicated that water soluble and available P levels in the soils initially decreased, then rapidly increased,and approached a steady state phase after approximately 20d. After 60d, water soluble P levels were significantly higher when litter was surface applied than when litter was incor porated. When the incubation was terminated, the net increase in available P in both soils was>100 mg P/*** efficient recycling of P and protection of water quality, application method and temperature should be considered when amending soils with poultry litter,

关键词： nutrient cycling phosphorus availability poultry litter water quality.

Subspace Search Method for Quadratic Programming With BoxConstraints

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Journal of Computational Mathematics 1999年第3期17卷 307-314页

作者： Zi-luan Wei(ICMSEC, chinese academy of sciences, beijing 100080, china) 中科院计算数学与科学工程计算所北京

A subspace search method for solving quadratic programming with box constraints is presented in this paper. The original problem is divided into many independent subproblem at an initial point, and a search direction is obtained by solving each of the subproblem, as well as a new iterative point is determined such that the value of objective function is decreasing. The convergence of the algorithm is proved under certain assumptions, and the numerical results are also given.

关键词： subspace search method quadratic programing matrix splitting