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The history of crustal uplift and metamorphic evolution of Panzhihua-Xichang micro-palaeoland, SW china:Constraints on Sm-Nd, ^(40)Ar/^(39)Ar and FT ages of granulites

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Science china Earth Sciences 2004年第8期47卷 689-703页

作者： XU Shijin1, LIU Wenzhong1, WANG Rucheng1, YU Hangbo1, LI Daming2. WAN Jinglin2.& FANG Zhong1 1. Department of Earth Sciences and state key {2. for Mineral Deposits Research, Nanjing University, Nanjing 2.0093, china 2. institute of Geology, china Seismological Bureau, beijing 10002., china 1. Department of Earth Sciences and state key {2. for Mineral Deposits Research Nanjing University 210093 Nanjing China 2. institute of Geology China Seismological Bureau 100029 Beijing China

Panzhihua-Xichang (Panxi) micro-palaeoland is the oldest terrane on the western margin of the Yangtze Block. Some intermediate-basic granulites are considered to be the crys-talline basement of lower crust in the terrane. Granulite-facies metamorphism of the granulites was developed in the period from 1186 Ma to 112. Ma. The origin of granulites was related to the collision orogenic process occurring when the micro-palaeolands merged to form the Rodinia supercontinent. Amphibolite-facies retrogressive metamorphism of granulites took place in the period from 877 Ma to 82. Ma. This period was consistent with the breakup time of the Rodinia supercontinent. 40Ar/39Ar ages and fission track (FT) ages of granulites in the Panxi mi-cro-palaeoland show that the vertical movement history of crustal rocks was a slow uplift process of the rigid terrane in the time from Neoproterozoic to Mesozoic. The subduction of India Plate towards Euroasia Plate resulted in the rapid uplift of the Qinghai-Tibetan Block in Cenozoic. Meanwhile, the Qinghai-Tibetan Block moved towards east. Consequently the Panxi terrane was uplifted rapidly. As a result of the collision orogeny between the Qinghai-Tibetan Block and the Panxi terrane, the granulite-facies crystalline basement in this region was exhumed and exposed to the surface.

关键词： granulite,isotope geochronology,crustal uplift movement,Panzhihua-Xichang region,western margin of Yangtze Block.

AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

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Science china Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. state key {2. of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, {2. 100085, china 2. School of Civil Engineering & Architecture, {2. Jiaotong University, {2. 100044, china 1. state key {2. of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. School of Civil Engineering & Architecture Beijing Jiaotong University Beijing 100044 China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 2.0 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR BRANCHED POLYETHYLENE

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Chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 state key {2. of Engineering Plastics The Center for Molecular Sciences {2. of Chemistry Chinese Academy of Sciences beijing 100080 china Chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2.rCl_2. were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2.rCl_2.and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2.rCl_2 Silica supported catalysts Branched polyethylene

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3 1. institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071, china 2. {2. {2. of Marine Science and Numerical Modeling, state Oceanic Administration, Qingdao 2.6061, china 3. Graduate School of the Chinese Academy of Sciences, beijing 100039, china 1. key laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School of the Chinese Academy of Sciences 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Synthesis and Crystal Structure of [Cis-1,10phenanthroline-palladium(Ⅱ)(THF)_2.dinitrate (THF = Tetrahydrofuran)

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Chinese Journal of Structural Chemistry 2003年第5期22卷 547-549页

作者： HUANG Hui YU Shu-Yan② (state key {2. of Polymer {2. and Chemistry, Joint {2. of Polymer Science and Materials, institute of Chemistry, The Chinese Academy of Sciences, beijing 100080, china) institute of Chemistry The Chinese Academy of Sciences State Key Laborator6y of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials CAS 北京 100080

A mononuclear complex, cis-1,10-phenanthroline-palladium(Ⅱ)(THF)2.dinitrate (THF = tetrahydrofuran) [Pd(C10H8N2.(C4H8O)2.(NO3)2.1, has been prepared and structurally characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P2./c with a = 7.881(1), b = 2..371(3), c = 10.178(1) ? ?= 103.313(3)? V = 2.36.5(4) 3, Mr = 554.83, Dc = 1.72. g/cm3, Z = 4, F(000) = 112. and (MoK) = 0.92. mm-1. The structure was refined to R = 0.0678 and wR = 0.1651 for 1687 observed reflections with I > 2.I). It is revealed that the central Pd(Ⅱ) ion in the title complex is bonded to two THF and two phenanthroline molecules in a cis-configuration to form the coordination geometry, deviating slightly from the square plane.

关键词： crystal structure Pd(Ⅱ) complex 1,10-phenanthroline

Hydraulic characteristics of converse curvature section and aerator in high-head and large discharge spillway tunnel

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Science china(Technological Sciences) 2011年第S1期54卷 33-39页

作者： LIU ZhiPing 1,2.ZHANG Dong 2.ZHANG HongWei 2.&WU YiHong 1,2.1 state key {2. of Simulation and Regulation of Water Cycle in River Basin,beijing 100038,china 2.5} institute of Water Resources and Hydropower Research,beijing 100038,china 1. state key {2. of Simulation and Regulation of Water Cycle in River Basin Beijing 100038 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China

The hydraulic characteristics and cavitation erosion near the converse curvature section in the high-head and large discharge spillway tunnel have been important issues of concern to the hydropower *** this paper,the evolutions of hydraulic elements such as pressure,flow velocity,wall shear stress,*** the converse curvature section are analyzed and the impacts of bottom aerator on hydraulic characteristics are discussed,with the commercial software FLUENT6.3 as a platform and combining the k-model and VOF *** flow pattern in the converse curvature section of spillway tunnel is given by the three-dimensional numerical *** indicates that the pressure changes rapidly with great pressure gradient from the beginning to the end of the *** also shows that the shear stress on side wall just downstream the end of the converse curvature curve is still increasing;the aeration cavity formed downstream the bottom aerator may cause the side wall pressure decreased to worsen the cavitation characteristics near the side *** means of the physical model experiment,the three-dimensional aerator composed of side wall baffling aerator and bottom aerator is studied,the baffling aerator suitable for the water flow conditions with water depth of 6.0 to 8.0 m and flow velocity of 35 to 50 m/s is proposed.

关键词： spillway tunnel baffling aerator converse curvature section hydraulic characteristics

A novel function for the cellulose binding module of cellobiohydrolase I

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Science china(Life Sciences) 2008年第7期51卷 620-629页

作者： WANG LuShan 1,2.,ZHANG YuZhong 1 &GAO PeiJi 1 1state key {2. of Microbial Technology,Shandong University,Jinan 2.0100,china 2.4} {2. of Nanoscale physics&Devices,Chinese Academy of Sciences,beijing 100080,china 1. state key {2. of Microbial Technology Shandong University Jinan 250100 China 2. beijing laboratory of Nanoscale{2. & Devices Chinese Academy of Sciences Beijing 100080 China

A homogeneous cellulose-binding module(CBM)of cellobiohydrolase I(CBHI)from Trichoderma pseudokoningii S-38 was obtained by the limited proteolysis with papain and a series of chromatographs *** of FT-IR spectra demonstrated that the structural changes result from a weakening and splitting of the hydrogen bond network in cellulose by the action of CBMCBHI at 40℃for 2. *** results of molecular dynamic simulations are consistent with the experimental conclusions, and provide a nanoscopic view of the mechanism that strong and medium H-bonds decreased dramatically when CBM was bound to the cellulose *** function of CBMCBHI is not only limited to locating intact CBHI in close proximity with cellulose fibrils,but also is involved in the structural disruption at the fibre *** present studies provided considerable evidence for the model of the intramolecular synergy between the catalytic domain and their CBMs.

关键词： cellulose cellulase cellobiohydrolase cellulose binding module hydrogen bonds molecular dynamics simulation

A novel method for evaluating and improving the 1H-MRSI glioma data quality

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Progress in Natural Science:Materials International 2005年第8期15卷 765-768页

作者： YUAN Kehong 1,2. LU Hongyu2. BAO Shanglian2., CHEN Qiansheng1, LI Shaowu3 and DUAN Chaijie2.1. key laboratory of Pure and Applied Mathematics, School of Mathematical Sciences, {2. 100871, china 2. The Research Center for Tumor Diagnosis and Therapeutical physics & the {2. key laboratory of Medical physics and Engineering, Peking University, {2. 100871, china 3. The Tian Tan Hospital, {2. 100050, china) key laboratory of Pure and Applied Mathematics School of Mathematical Sciences Beijing 100871 China. The Research Center for Tumor Diagnosis and Therapeutical physics & the beijing {2. {2. of Medical physics and Engineering Peking University Beijing 100871 China. The Tian Tan Hospital Beijing 100050 China

Metabolic information obtained by proton magnetic resonance spectroscopic imaging (1H-MRSI) has been approved to be a powerful tool to identify either benign or malignant glioma, as well as to confirm the tumor level. However, 1H-MRSI data are affected by various factors, such as the thermal noise, eddy currents, susceptibility artifacts, and rigid body motion. To get accurate quantitative metabolic information, the key problem is to assess the 1H-MRSI data quality. In this paper, we introduce a new evaluating system to filter the data, and a new method, called wavelet denoising method, to improve the data quality under the evaluating system. Experimental results on 1H-MRSI glioma data demonstrate that preprocessing is prerequisite and the proposed algorithm with evaluating system is effective.

关键词： 1H-MRSI evaluating system glioma data quality wavelet denoising

Sediment transport capacity of hyperconcentrated flow

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Science china(physics,Mechanics & Astronomy) 2008年第8期51卷 961-975页

作者： SHU AnPing1,2.& FEI XiangJun2.1 School of Environment & key laboratory of Water and Sediment Sciences,Ministry of Education,{2. Normal University,{2. 100875,china 2.state key laboratory of Hydroscience and Engineering,Tsinghua University,{2. 100084,china School of Environment & key laboratory of Water and Sediment Sciences Ministry of Education Beijing Normal University Beijing 100875 China state key {2. of Hydroscience and Engineering Tsinghua University Beijing 100084 China

As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

关键词： hyperconcentrated flow turbulent energy equilibrium efficiency coefficient sediment transport capacity