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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2. SONG Shuguang3 & ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069,{2. 2. The Geological Lab Center,{2. university of Geosciences (beijing), beijing 100083,{2. 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, peking university, beijing 100871,{2. 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 2. km2. is the largest ultramafic massif in the eastern Qinling orogenic belt, Central{2.. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2.3, CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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Calculation of traversal time in tunneling by double-wave theory

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Chinese Science Bulletin 1998年第9期43卷 723-727页

作者： HUANG Xiangyou Department of Physics, peking university, beijing 100871,{{2. Department of Physis Peking University Beijing China

Becausethe information contained in a wave function is not enough to describe an individual particle, the suggestion to define the state of a particle by two-wave functions is used. In the double-wave description, a general formula telling the traversal time of a particle in tunneling is obtained. When the double-wave description over an initial parameter is averaged , it reduces to the usual description. Two new relations between the transmission and the reflected coefficients are founded in the new cescription.

关键词： tunneling double-wave theory ensemble.

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CONVERGENCE OF CHORIN-MARSDEN FOR MULA FOR THENAVIER-STOKES EQUATIONS ON CONVEX DOMAINS

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Journal of Computational Mathematics 1999年第1期17卷 73-88页

作者： Lung-an Ying(Research institute for Mathematical Sciences, Kyoto university, Japan Department of Mathematics, peking university,{{2., china) peking Univ Dept Math Beijing 100871 Peoples R China Kyoto Univ Math Sci Res Inst Kyoto Japan

We prove the convergence of the Chorin-Marsden product formula for solving the initial-boundary value problems of the Navier-Stokes equations on convex domains. As a particular case we consider the case of the half pl... 详细信息

关键词： Navier Stokes equation vortex method fractional step method convergence

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Pole assignment in descriptor periodic systems

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Science china Mathematics 2005年第10期48卷 1309-1332页

作者： FAN Hung-Yuan~1 LIN Wen-Wei~1 & XU Shufang~2.1. Department of Mathematics,Tsing Hua university,Hsinchu 30043,{2. 2. LMAM,School of Mathematical Sciences,{2. university,beijing 100871,{2. 1. Department of Mathematics Tsing Hua University 30043 Hsinchu China 2. LMAM School of Mathematical Sciences Peking University 100871 Beijing China

In this paper a pole assignment problem is considered for the descriptor linear discrete-time periodic systems, which is using the periodic proportional-derivative feedback to modify a given system such that the closed loop system has a specified selfconjugate set of eigenvalues. It is shown that the complete reachability of an open loop periodic system is equivalent to the possibility of assigning an arbitrary set of the eigenvalues to the system by choosing the suitable periodic proportional-derivative feedback.A computational approach is also proposed to solve the problem, which uses the reliable numerical techniques based on the orthogonal transformations. Numerical examples are presented to illustrate the effectiveness of the proposed approach.

关键词： descriptor linear periodic system, pole assignment, proportional and derivative feedback, numerical method, periodic Schur decomposition.

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When Closed Graph Manifolds are Finitely Covered by Surface Bundles Over S^1

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Acta Mathematica Sinica,English Series 1999年第1期15卷 11-20页

作者： Yan Wang Fengchun YuDepartment of Mathematics,peking university,{{2. 100871 P.R.china Department of Mathematics Peking University Beijing P. R. China

The problem of deciding whether a graph manifold is finitely covered by a surface bundle over the circle is discussed in this paper.A necessary and sufficient condition in term of the solutions of a certain matrix equation is obtained,as well as a necessary condition which is easy to compute. Our results sharpen and extend the earlier results of ***,***,and ***-F. Yu in this topic.

关键词： Surface bundle Covering Graph manifolds

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Multiuser detection algorithm based on belief propagation in multiple-input multiple-output systems

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Science in china(Series F) 2004年第3期47卷 384-393页

作者： JIANG Wei XIANG Haige Department of Electronics, peking university, beijing 100871,{{2. 1. Department of Electronics Peking University 100871 Beijing China

In MIMO (multiple-input, multiple-output) systems, signals from differenttransmitting antennas interfere at each receiving antenna and multiuser detection (MUD)algorithms may be adopted to improve the system performance. This paper proposes anovel multiuser detection algorithm in MIMO systems based on the idea of 'beliefpropagation' which has achieved great accomplishment in decoding of low-densityparity-check codes. The proposed algorithm has a low computation complexityproportional to the square of transmitting/receiving antenna number. Simulation resultsshow that under low signal-to-noise ratio (SNR) circumstances, the proposed algorithmoutperforms the traditional linear minimum mean square error (MMSE) detector while itencounters a 'floor' of bit error rate under high SNR circumstances. So the proposedalgorithm is applicable to MIMO systems with channel coding and decoding. Although inthis paper the proposed algorithm is derived in MIMO systems, obviously it can be appliedto ordinary code-division multiple access (CDMA) systems.

关键词： multiple-input multiple-output belief propagation multiuser detection

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Lie map for the nonlinear transport of continuous intense beams in the axial-symmetric electrostatic fields

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Progress in Natural Science:Materials International 2008年第7期18卷 795-800页

作者： Jianqin L*, Xiaosong Zhao Institute of Heavy Ion Physics, peking university, beijing 100871,{{2. Institute of Heavy Ion Physics Peking University Beijing 100871 China

Nonlinear transport of intense continuous beam in the axial-symmetric electrostatic fields is analyzed with the Lie algebraic method. The K-V particle distribution is adopted in the analysis. The results obtained can be used in the calculations of the intense continuous beam dynamics in the beam optical systems consisting of drift spaces, electrostatic lenses, and DC electrostatic accelerating tubes. A com- puter code has been designed for practical simulations. To meet the needs of accurate calculation, all the elements are divided into many small segments, the electric fields in each segment are regarded as uniform fields, and the dividing points are treated as thin lenses. Iter- ation procedures are adopted in the code to obtain self-consistent solutions. The code can be used to design low energy dc beam transport systems, electrostatic accelerators, and ion implantation machines.

关键词： Intense continuous beam Lie algebraic analysis Nonlinearity

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Synthesis and Crystal Structure of 4,6Di-tert-butyl-2.hydroxy-3-(N-1-phenylethyliminomethyl) phenyl bis(triphenylphosphine)palladium bromide

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Chinese Journal of Structural Chemistry 1999年第4期18卷 54-59页

作者： XU JiaXi\ ZHANG ZeYing\= (College of Chemistry and Molecular Engineering, peking university, beijing 100871,{{2.) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａｃｔｉｏｎｏｆｃａｒｂｏｎｃａｒ...

关键词： palladium complex synthesis molecular structure crystal structure

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Study on urban water environmental support capacity

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Journal of Environmental Sciences 1995年第4期7卷 430-434页

作者： Guo Huaicheng Ye Wenhu(Center of Environmental Sciences , peking university , beijing 100871 ,{{2.) Ctr of Envmtl Sciences Peking Univ Beijing China China

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒ... 详细信息

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７...

关键词： water environmental support capacity urban water environment development variablesi supportvariables.

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Skara hunanensis a new species of Skaracarida (Crustacea) from Upper Cambrian (Furongian) of Hunan,south china

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Progress in Natural Science:Materials International 2007年第8期17卷 934-942页

作者： Liu Jie Dong Xiping~(**) (School of Earth and Space Science,peking university,{{2. 100871,china) [a]School of Earth and Space Science Peking University Beijing China

The fossils of Orsten-type preservation are as famous as Chengjiang Fauna in the world,but it was not until 2.05 that the Orsten-type fossils represented by Skaraearida and Phosphatocopida were first reported to be found in western Hunan,South china. Here,we report the systematic paleontology of all the exquisitely preserved specimens belonging to *** were found at a same horizon of Upper Cambrian (Furongian) in Wangcun section,western Hunan,south china,assigned to a new species Skara huna- nensis *** hunanensis is characterized by small,soft-integumented,marine forms with slender,annulate body;labrum large and ventrocaudally directed;uniramous antennulae;biramous antennae and mandibulae;maxillas and maxillipeds of the same shape;all postantennular limbs join a short cephalic filter *** body has two tagmata:a cephalon with five pairs of well developed ap- pendages and a trunk composed of 11 ring-shaped conical segments.

关键词： Skara hunanensis Skaracarida Crustacea Upper Cambrian Furongian Hunan

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