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Discussion on measurement and calculation principle of petrogenetic depth

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chinese Science Bulletin 1999年第24期44卷 2293-2295页

作者： LU Guxian and LIU Ruixun Institute of Geomechanics , chinese academy of Geological sciences , beijing 100081 ,{4. Department of Geology, Peking University, beijing 100871,{4. Institute of Geomechanics Chinese Academy of Geological Sciences Beiing China Department of Geology Peking University Beijing China

Geologic and geophysical data certificate that lithosphere and its down rock behave as solid, therefore,it is better to measure petrogenetic and metallogenetic depth according to internal stress of solid states. Lithomechanic experiment found that the bigger the confining pressure, the bigger the tensile and shear strength of rocks,so rock can bear very high differential stress but it is not broken. Sibson put forward that the property of rocks under 10-15km of the surface changes from brittle to ductile (rather than from elastic to plastic). Rock with ductile de-

关键词： petrogenetic depth solid stress state tectono-original additional hydrostatic pressure rock strength.

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, beijing 10004.,{4.) Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 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.

Applications of URANS on predicting unsteady turbulent separated flows

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Acta Mechanica Sinica 2009年第3期25卷 319-324页

作者： Jinglei Xu Huiyang Ma Department of Physics, Graduate University of the chinese academy of sciences, 10004. beijing,{4. Department of Physics Graduate University of the Chinese Academy of Sciences Beijing China

Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2D flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS （URANS）. Some typical linear and nonlinear eddy viscosity turbulence models （LEVM and NLEVM） and a quadratic explicit algebraic stress model （EASM） are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding.

关键词： URANS Nonlinear eddy viscosity turbulencemodel ,Separated flows Circular cylinder

The gravity wave instability induced by photochemistry in summer polar mesopause region

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chinese Science Bulletin 2000年第3期45卷 267-272页

作者： Center for Space Science and Applied Research, chinese academy of sciences, beijing 100080,{4. Laboratory of Numeric Study of Heliospheric Physics, chinese academy of sciences, beijing 100080,{4. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Laboratory of Numeric Study of Heliospheric Physics Chinese Academy of Sciences Beijing China

The effect of diabatic process due to the photochemical heating and cooling on the gravity wave propagation in middle atmosphere is studied. A linear gravity wave model which considers the diabatic process is established. The unstable region and the growth rate of the gravity wave caused by photochemistry are calculated. And the comparison between the model and the adiabatic gravity wave theory of pure dynamics is made. The results indicate that the photochemical heating process can induce the instability of gravity wave at mesopause. The intensity of the instability becomes stronger as the temperature decreases. The temperature feature and the altitude characteristics of the instability are consistent with the observation. Therefore, the instability of the gravity wave induced by photochemistry may be an important mechanism in polar mesopause region in summer.

关键词： photochemistry instability gravity wave growth rate.

Studies on BEPC upgrade from pretzel to double-ring

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2084-2089页

作者： ZHANG Chuang Institute of High Energy Physics,chinese academy of sciences,beijing 10004.,{4. chinese academy of sciences Institute of High Energy Physics Beijing China (GRID:grid.9227.e) (ISNI:***)

Physics opportunity in the charm and τ energy region calls for higher luminosity of the beijing Electron-Positron Collider (BEPC).The BEPC has experienced continuous improvement since its completion in ***,as a major upgrading project of the BEPC,aims at enhancing its luminosity of factor 30–100,following the principle of "one machine,two purposes" as adopted in BEPC,so that both high energy physics and synchrotron radiation experiments can be carried out with *** the BEPC to BEPCII,the double-ring scheme with multi-bunch e +-e-collision in the large crossing angle was studied in comparison with the single-ring pretzel *** the dedicated synchrotron radiation operation,artful "bridges" are designed to connect two halves of the outer ring in both the southern and the northern crossing *** paper reviews the studies on the BEPC upgrade from pretzel to double-ring structure of BEPCII.

关键词： collider storage ring high energy physics synchrotron radiation

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 10004.,{4. Institute of High Energy Physics Chinese Academy of Sciences Beijing 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(1835), 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(3770) 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

FOURIER-LEGENDRE PSEUDOSPECTRAL METHOD FOR THE NAVIER-STOKES EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 225-238页

作者： Jian Li (LSEC, Institute of Computational Mathematics and Scientific/Engineering Computing, academy of Mathematics and System sciences, chinese academy of sciences, beijing, 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京 100080

Constructs a Fourier-Legendre pseudospectral scheme for Navier-Stokes equations with semi-periodic boundary condition. Equation of the scheme; Estimation of errors; Numerical results.

关键词： Navier-Stokes equations Fourier-Legendre pseudospectral method error estimation

Trend of urban system structure under the restriction of water and land resources in Xinjiang

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chinese Science Bulletin 2006年第A01期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china Institute of Geographical Science and Natural Resources Research, chinese academy of sciences, beijing 100101, china Graduate School, chinese academy of sciences, beijing 100039, china Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Institute of Geographical Science and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School Chinese Academy of Sciences Beijing 100039 China

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 Xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

An improved δ-Eddington approximation

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chinese Science Bulletin 1999年第4期44卷 304-309页

作者： QIU JinhuanInstitute of Atmospheric Physics , chinese academy of sciences , beijing 100029,{4. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

Based on an accuracy analysis of two-stream approximations, an improved δ-Eddington ap-proximation is developed. The approximation has much better accuracy than all exiting two-stream ap-proximations as the optical depth is less than unity. As the surface reflectance is zero and the opticaldepth is less than unity, errors in both transmission and reflection calculated by the present approxima-tion are more one time less than those by other two-stream approximations. In the case of aerosol opti-cal depth of4.% and one times lessthan those by Eddington or δ-Eddington.

关键词： radiation flux fractional factor of δ-function Eddington approximation.