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Mineralization episode of porphyry copper deposits in the Jinshajiang-Red River mineralization belt: Re-Os dating

Science china Earth sciences 2005年第2期48卷 192-198页

作者： WANG Denghong, QU Wenjun, LI Zhiwei, YIN Hanlong4 & CHEN Yuchuan institute of Mineral Resources, chinese academy of Geological {3., beijing 10003., china national Center of Rock and Mineral Analysis, chinese academy of Geological {3., beijing 10003., china Resource Assessment Center of Yunnan, Kunming 650011, china institute of Geology and Geophysics, chinese academy of sciences, beijing 100101, china chinese academy of Geological {3., beijing 10003., china 1. institute of Mineral Resources Chinese Academy of Geological Sciences 100037 Beijing China 2. national Center of Rock and Mineral Analysis Chinese Academy of Geological Sciences 100037 Beijing China 3. Resource Assessment Center of Yunnan 650011 Kunming China 4. institute of Geology and Geophysics Chinese Academy of Sciences 100101 Beijing China 5. chinese academy of Geological sciences 100037 Beijing China

Re-Os isotopic dating for the molybdenites from the porphyry copper deposits of the Jinshajiang-Red River mineralization belt in Yunnan Province yields isochron ages of 3..9±1.1 Ma for the Machangqing deposit and 3..4±0.5 Ma for the Tongchang deposit. This result shows that both the Machangqing and the Tongchang porphyry Cu-Mo deposits from two different ore-fields formed simultaneously. This new data and the published Re-Os model ages of molybdenite (3..4 Ma, 3..9 Ma, 3..2 Ma) of the Yulong porphyry copper deposit in Tibet, which is located in the same Jinshajiang-Red River mineralization belt as the Machangqing deposit and the Tongchang deposit, suggest that these three Cenozoic porphyry copper deposits in the Jinshajiang-Red River mineralization belt were contemporary for their mineralization episode. That is to say, even their present locality is far away and nearly iso-distantly distributed, these three porphyry Cu(Mo) deposits belong to the same mineralization episode at the end of Eocene.

关键词： Re-Os isotopic dating, porphyry Cu deposits, Cenozoic, mineralization episode.

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Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science china Earth sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2, DING Yihui3.& ZHANG Renhe2 1. Jiangsu Key laboratory of Meteorological Disaster (KLME), Nanjing institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 210044, china 2. State Key laboratory of Severe Weather (LaSW), chinese academy of Meteorological sciences, beijing 100081, china 3. national Climate Center, chinese Meteorological Administration, beijing 100081, china 1. Jiangsu Key laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. State Key laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. national Climate Center Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

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New Dispersed Phase of Electrorheological Fluids:TiO_2 Coating Graphite Particles

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Journal of Materials Science & Technology 2000年第5期16卷 529-530页

作者： Sujuan XU+ and Biao WANG (Harbin institute of Technology, Harbin 150001, china) Shouqiang MEN and Kunquan LU (institute of Physics,{3., beijing 100080, china) Harbin institute of Technology Harbin 150001 China institute of Physics Chinese Academy of Sciences Beijing 100080 China

We have prepared novel coated particles, with a conductor graphite core and a dielectric TiO2 coating, as the dispersed phase of electrorheological fluids. One order of magnitude enhancement in the shear stress is obtained by using such composite particles, when it is compared with that of TiO2 particles. The experimental results show a way to get excellent ER system.

关键词： New Dispersed Phase of Electrorheological Fluids Graphite TiO

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Hyperconcentrated flows as influenced by coupled wind-water processes

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Science china Earth sciences 2005年第11期48卷 1990-2000页

作者： XU Jiongxin institute of Geographical sciences and Natural Resources Research, chinese academy of sciences Key {3. of Water Cycle and Related Land Surface Processes, chinese academy of sciences, beijing 100101, china 1. Key laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Using data from more than 40 rivers in the middle Yellow River basin, a study has been made of the influence of coupled wind-water processes on hyperconcentrated flows. A simple “vehicle” model has been proposed to describe hyperconcentrated flows. The liquid phase of two-phase flows is a “vehicle”, in which coarse sediment particles are carried as solid-phase. The formation and characteristics of hyperconcentrated flows are closely related with the forma-tion and characteristics of this liquid-phase and solid-phase. Surface materials and geomorphic agents of the middle Yellow River basin form some patterns of combination, which have deep influence on the formation and characteristics of liquid- and solid-phases of hyperconcentrated flows. The combination of high percentages of relatively coarse material with low percentages of fine material appears in the area predominated by the wind process, where the supply of rela-tively coarse sediment is sufficient, but the supply of relatively coarse sediment is not. The com-bination of low percentages of relatively coarse material with high percentages of fine material appears in the area predominated by the water process, where the supply of fine sediment is sufficient, but the supply of fine sediment is not. In the area predominated by coupled wind-water processes appears the combination of medium percentages of coarse and fine materials, and thus both coarse and fine sediments are in relatively sufficient supply. The manner in which the mean annual sediment concentrations of liquid- and solid-phases vary with total suspended sediment concentration is different. With the increased total suspended sediment concentration, mean annual sediment concentration of liquid-phase increased to a limit and then remained constant; however, mean annual sediment concentrations of solid-phase in-creased continuously. Thus, the magnitude of total suspended sediment concentration depends on the supply conditions of relatively coarse sedime

关键词： river sediment, hyperconcentrated flows, liquid-solid two-phase flows, wind process, fluvial process, Yellow River

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SYNTHESIS AND CHARACTERIZATION OF BIS-[2-[[(2-ALKOXYPHENYL)IMINO]METHYL]-PHENOLATO-O,N,O]NICKEL(II)COMPLEXES AND THEIR NORBORNENE POLYMERIZATION

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chinese Journal of Polymer Science 2005年第6期23卷 619-626页

作者： Dong-heng Zhang Su-yun Jie Hai-jian Yang Fei Chang and Wen-hua Sun Key laboratory of Engineering Plastics,institute of Chemistry,chinese {3. of sciences,beijing 100080,china chinese Acad Sci Inst Chem Key Lab Engn Plast Beijing 100080 Peoples R China

A series of salicylaldimines, synthesized in high yield via microwave-assisted condensation of salicylaldehyde and 2-alkoxyaniline were allowed to react with nickel chloride to form six-coordinated nickel complexes. These nickel complexes were carefully characterized, and the solid structure of la was elucidated by X-Ray diffraction. Activated with MAO, the nickel complexes showed good activity for homopolymerization of norbornene. Reaction parameters, such as the ratio of nickel precursor to MAO, monomer concentration, reaction time and the reaction temperature, as well as the nature of the ligands were found to have significant effects on the catalytic activity and some properties of the resulting polynorbornene.

关键词： Salicylaldirnine Nickel complex Norbornene Vinyl polymerization

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Direct Optimization of Low-thrust Many-revolution Earth-orbit Transfers

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chinese Journal of Aeronautics 2009年第4期22卷 426-433页

作者： Gao Yang academy of Opto-Electronics,chinese academy of {3.,beijing 100190,china [a]academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China

Low-thrust Earth-orbit transfers with 10^- 5-order thrust-to-weight ratios involve a large number of orbital revolutions which poses a real challenge to trajectory optimization. This article develops a direct method to optimize minimum-time low-thrust many-revolution Earth-orbit transfers. A parameterized control law in each orbit, in the form of the true optimal control, is proposed, and the time history of the parameters governing the control law is interpolated through a finite number of nodal values. The orbital averaging method is used to significantly reduce the computational workload and the trajectory optimization is conducted based on the orbital averaging dynamics expressed by nonsingular equinoctial elements. Furthermore, Earth＇s shadowing and perturbation effects are taken into account. The optimal transfer problem is thus converted to the parameter optimization problem that can be solved by nonlinear programming. Taking advantage of the mapping between the parameterized control law and the Lyapunov control law, a technique is proposed to acquire good initial guesses for optimization variables, which results in enlarged convergence domain of the direct optimization method. Numerical examples of optimal Earth-orbit transfers are presented.

关键词： low thrust orbital transfer optimization direct method orbital averaging Lyapunov method

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Prediction method for October 2003.solar storm

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Science china(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2, 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2 1. State Key laboratory of Space Weather, Center for Space Science and Applied Research, chinese academy of sciences, beijing 100080,{3. 2. Graduate School, chinese academy of sciences, beijing 10003.,{3. 3. institute of Meteorology, PLA University of Science and Technology, Nanjing 211101,{3. State Key laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 28 and 29, 2003. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

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Comparative study on the effect of integrin αvβ3.on secretion of matrix metalloproteinases in human normal and carcinoma trophoblasts

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Progress in Natural Science:Materials International 2005年第11期15卷 982-987页

作者： BAI Suxia, FU Yayuan, KONG Gang and WANG Yanling (State Key laboratory of Reproductive Biology, institute of Zoology, chinese academy of sciences,{3., china The Second Hospital of chinese Medicine College, Shenyang 110003. china) State Key laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. The Second Hospital of chinese Medicine College Shenyang 110003 China

The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integnn αvβ3.on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and chorio-carcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophobiast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast cells is up-regulated by anti-αvβ3.antibody, whereas, decreased in choriocarcmoma cells. It was suggested that αvβ3.can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.

关键词： cytotrophoblast cells choriocarcinoma cells integrfn αvβ3 matrix metalloproteinase.

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RHEOLOGICAL BEHAVIOR OF EPOXY RESIN WATERBORNE DISPERSIONS

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chinese Journal of Polymer Science 2001年第5期19卷 471-476页

作者： Zhen-zhong Yang Yuan-ze Xu De-lu Zhao State Key laboratory of Polymer Physics & Chemistry, Center for Molecular Science institute of Chemistry, chinese academy of sciences,{3. china chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Ctr Mol Sci Beijing 100080 Peoples R China

The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique. Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.

关键词： epoxy resin waterborne dispersion rheological behavior cluster-cluster aggregation percolation transition

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Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3., HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 Key laboratory of Optical Astronomy, national Astronomical Observatories, chinese academy of sciences, {3. 100012, china 2 Key laboratory for Particle Astrophysics, institute of High Energy Physics, chinese academy of sciences, {3. 100049, china 3.Graduate University of the chinese academy of sciences, {3. 100049, china 4 Department of Physics, Nanjing Normal University, Nanjing 210011, china 1. Key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

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