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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 Sciences,{3. 100101,china)Li Xiuxia(institute of High Energy Physics,chinese academy of Sciences,{3. 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

A new approach of cascade utilization of the chemical energy of fuel

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Progress in Natural Science:Materials International 2006年第5期16卷 518-523页

作者： HAN Wei, JIN Hongguang and LIN Rumou ( institute of Engineering Thermophysics, chinese academy of Sciences, {3. 100080, china Graduate School of the chinese academy of Sciences, {3. 100080, china) [a]institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China [b]Graduate School of the chinese academy of Sciences Beijing China

The indirect release of chemical energy of fuel is investigated, and a new mechanism is proposed to identify the cascade utilization of chemical energy of fuel more clearly. Based on the concept of energy level, the internal phenomenon of the indirect chemical energy release is disclosed, and the equations of energy level describing the utilization of chemical energy and thermal energy during the indirect chemical energy release process are obtained. From theoretical analysis, we find that the superiority of the indirect chemical energy release of fuel comes from the cascade utilization of the fuel's chemical energy. Moreover, the cascade utilization of chemical energy is verified by the investigation of CRGT (chemically recuperated gas turbine). As a result, the thermal exergy obtained from the chemical energy release of fuel increases by 2 % -3.% . The results obtained here may help a deeper understanding of indirect chemical energy release of fuel and provide a theoretical basis for the synthesis of innovative energy systems.

关键词： chemically recuperated gas turbine methane/steam reforming chemical energy level cascade utilization.

Modeling on runoff concentration caused by rainfall on hillslopes and application in Maoping slope

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Progress in Natural Science:Materials International 2006年第10期16卷 1056-1065页

作者： LIU Qingquan and LI Jiachun (institute of Mechanics, chinese academy of Sciences, {3. 100080, china) [a]chinese academy of Sciences' Institute of Mechanics' Beijing China

Based on the fact that the concentration flowlines of overland flow depend on the surface landform of hillslope, a kinematic wave model was developed for simulating runoff generation and flow concentration caused by rainfall on hillslopes. The model-simulated results agree well with the experimental observations. Applying the model to the practical case of Maoping slope, we obtained the characteristics of runoff generation and infiltration on the slope. Especially, the simulated results adequately reflected the confluent pattern of surface runoff, which offers a scientific foundation for designing the drainage engineering on the Maoping slope.

关键词： complex hillslope rainfall infiltration overland flow runoff concentration Maoping slope.

Some problems on the studies of the late Pleistocene human evolution and formation of modern human populations

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Progress in Natural Science:Materials International 2006年第12期16卷 1233-1241页

作者： LIU Wu(institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of Sciences, {3. 100044, china) [a]institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China

For the past two decades, studies and debates on the modern human origins around the world have attracted attentions to the late Pleistocene human evolution and formation of modern human populations, and some controversial hypotheses and problems have been proposed. In the present paper, some problems on the late Pleistocene human evolution, and the formation and differentiations of modern human populations in china are studied with a brief description and comments on the research advances in this field.

关键词： late Pleistocene human evolution formation and differentiation of modern human population paleoanthropology.

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, {3. 100049, china 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

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 {3.. china 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

Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3. ZHOU Su3. LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3.1. institute of Geology, chinese academy of Geological Sciences,{3., china 2. Development and Research Center, china Geological Survey,{3., china 3. china University of geosciences, beijing 100083. china 4. china University of geosciences, Wuhan 43.074, china 5. Information Center of Ministry of Land and resources, beijing 100812, china 6. institute of Geology, State Seismological Bureau, beijing 100029, china 1. institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china University of geosciences 100083 Beijing China 4. china University of geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and resources 100812 Beijing China 6. institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

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, {3. 100080, china) [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.

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 {3. 100080, china 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