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Journal of Computational Mathematics 1997年第4期15卷 319-326页

作者： Lie-heng Wang (state key laboratory of Scientific and Engineering Computing, ICMSEC,{3., beijing, 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

This paper is devoted to study of an iterative procedure for domain decomposition method of second order elliptic problem with mixed boundary conditions (i.e., Dirichlet condition on a part of boundary and Neumann condition on the another part of boundary). For the pure Dirichlet problem, Marini and Quarteroni [3., [4] considered a similar approach, which is extended to more complex problem in this paper.

关键词： EH Math AN ITERATIVE PROCEDURE FOR DOMAIN DECOMPOSITION METHOD OF SECOND ORDER ELLIPTIC PROBLEM WITH MIXED BOUNDARY CONDITIONS

Markov chain approach to identifying Wiener systems

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Science china(Information sciences) 2012年第5期55卷 1201-1217页

作者： ZHAO WenXiao 1,2 & CHEN HanFu 1,2 1 key laboratory of Systems and Control,Institute of Systems Science,AMSS,chinese {3. of sciences,beijing 100190,china 2 National Center for Mathematics and Interdisciplinary sciences,chinese {3. of sciences,beijing 100190,china 1. key laboratory of Systems and Control Institute of Systems Science AMSS Chinese Academy of Sciences Beijing 100190 China2. National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of Sciences Beijing 100190 China

Identification of the Wiener system composed of an infinite impulse response (IIR) linear subsystem followed by a static nonlinearity is *** recursive estimates for unknown coefficients of the linear subsystem and for the values of the nonlinear function at any fixed points are given by the stochastic approx-imation algorithms with expanding truncations (SAAWET).With the help of properties of the Markov chain connected with the linear subsystem,all estimates derived in the paper are proved to be strongly *** comparison with the existing results on the topic,the method presented in the paper simplifies the convergence analysis and requires weaker conditions.A numerical example is given,and the simulation results are consistent with the theoretical analysis.

关键词： Wiener system recursive identification stochastic approximation Markov chain strong consis-tency

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 {3., Center for Space Science and Applied Research, chinese academy of sciences, beijing 100080, china 2. Graduate School, chinese academy of sciences, beijing 10003., china 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 211101, china state key laboratory of Space {3. 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.

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3. SHI Yuruo3.& MIAO Laicheng4 1. key laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of sciences, Guangzhou 510640,{3. 2. Graduate University of chinese academy of sciences, beijing 10003.,{3. 3. SHRIMP isotope laboratory, chinese academy of Geological sciences, beijing 10003.,{3. 4. Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029,{3. key laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China SHRIMP isotope laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4 ± 3.0 Ma and 23..4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/23.U age of 23..0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~23. Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

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 laboratory of Engineering Plastics The Center for Molecular {3. Institute of Chemistry chinese academy of {3. 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_2ZrCl_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_2ZrCl_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_2ZrCl_2 Silica supported catalysts Branched polyethylene

Study of the effect of atorvastatin on the interaction between ICAM-1 and CD11b by live-cell single-molecule force spectroscopy

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Science china Chemistry 2010年第4期53卷 752-758页

作者： LI Yi1, SHI XiaoLi2, LIU HuiLiang1, YI ShaoQiong3. ZHANG XueJie2 & FANG XiaoHong2 1Department of Cardiology, the General Hospital of chinese People’s Armed Police Forces, beijing 10003., china 2beijing National laboratory for Molecular sciences Institute of Chemistry, chinese academy of sciences, beijing 100190, china 3.9} key laboratory of Pathogen and Biosecurity beijing Institute of Microbiology and Epidemiology, beijing 100071, china 1. Department of Cardiology the General Hospital of Chinese People’s Armed Police Forces Beijing 100039 China2. Beijing National Laboratory for Molecular Sciences Chinese Academy of Sciences Beijing 100190 China4. Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China3. State Key Laboratory of Pathogen and Biosecurity Beijing 100071 China5. Beijing Institute of Microbiology and Epidemiology Beijing 100071 China

The interaction between the cell adhesion molecule CD11b and its ligand ICAM-1 plays an important role in inflammatory responses in the disease of atherosclerosis. Atorvastatin is a commonly prescribed statin drug which has been considered as one of the most potent therapeutic agents for atherosclerosis due to its lipid-lowering effect. Recently, there is a growing body of evidence that atorvastatin has anti-inflammatory effect. We have applied the advanced method of live-cell single-molecule force spectroscopy to investigate the effect of atorvastatin on adhesion force between ICAM-1 and CD11b. Our result showed that single-molecule binding force of ICAM-1 and CD11b detected by AFM in the living cells was about 40 pN, and atorvastatin did not affect this force by blocking ICAM-1 or CD11b. This was different from the ICAM-1 monoclonal antibody, which could directly reduce the binding force of ICAM-1 and CD11b. Flow cytometry results revealed that atorvastatin pretreatment decreased the ICAM-1 expression in TNF-α activated HUVECs, which may contribute to its anti-inflammatory effect. The study provides a new approach to study anti-inflammatory mechanism for clinic drugs.

关键词： atherosclerosis atorvastatin atomic force microscopy single-molecule force spectroscopy protein-protein interaction

Research of the Gas-solid Flow Character Based on the DEM Method

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Journal of Thermal Science 2011年第6期20卷 521-526页

作者： Xueyao Wang and Yunhan Xiao Research Center for Clean Energy and Power,chinese academy of sciences {3. laboratory of Advanced Energy and Power,chinese academy of sciences (Institute of Engineering Thermophysics),beijing,100190,china Research Center for Clean Energy and Power Chinese Academy of Sciences Beijing China key laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Numerical simulation of gas-solid flow behaviors in a rectangular fluidized bed is carried out three dimensionally by the discrete element method (DEM).Euler method and Lagrange method are employed to deal with the gas phase and solid phase *** collided force among particles,striking force between particle and wall,drag force,gravity,Magnus lift force and Saffman lift force are considered when establishing the mathematic ***-sphere model is used to describe the collision of *** addition,the Euler method is also used for modeling the solid phase to compare with the results of *** flow patterns,particle mean velocities,particles' diffusion and pressure drop of the bed under typical operating conditions are *** results show that the DEM method can describe the detailed information among particles,while the Euler-Euler method cannot capture the micro-scale *** matter which method is used,the diffusion of particles increases with the increase of gas *** the gathering and crushing of particles cannot be simulated,so the energy loss of particles' collision cannot be calculated and the diffusion by using the Euler-Euler method is *** addition,it is shown by DEM method,with strengthening of the carrying capacity,more and more particles can be schlepped upward and the dense suspension upflow pattern can be ***,the results given by the Euler-Euler method are not consistent with the real situation.

关键词： DEM gas-solid flow numerical simulation

CBCR:CBC MAC with rotating transformations

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Science china(Information sciences) 2011年第11期54卷 2247-2255页

作者： ZHANG LiTing 1,2,WU WenLing 1,ZHANG Lei 1 & WANG Peng 21 state key laboratory of Information Security,Institute of Software,{3. academy of sciences,beijing 100190,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 1. state key laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Message authentication codes (MACs) are widely used to protect data integrity and data origin authentication in *** this paper,we propose a new block-cipher-based MAC algorithm,CBCR,with provable security for arbitrary-length *** adopts rotating operations in the end of cipherblock-chaining structure,and it appends fixed-length prefixes to all messages,which implies flexible usages in *** example,these fixed-length prefixes can be filled with some security parameters,message redundancies,*** also propose CBCR0,a special case of CBCR that sets its prefix to be an all-zero *** with CMAC,a recommended standard by the US National Institute of Standards and Technology (NIST),CBCR0 enjoys all the advantages that CMAC has,but requires less memory;so,in practical applications,CBCR0 behaves as well as CMAC does,and it is even more suitable for environments with limited memory resources,*** cards.

关键词： message authentication code cipher block chaining block cipher provable security

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1,2 & ZHOU GuangSheng1 1 state key laboratory of Vegetation and Environmental Change, Institute of Botany,{3., beijing 100093. china 2 Graduate University of{3., beijing 100049, china 1. state key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in china from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast china Transect (NECT) and the North-South Transect of Eastern china (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Carbon Storage and Vertical Distribution in Three Shrubland Communities in Gurbantünggüt Desert,Uygur AutonomousRegion of Xinjiang,Northwest china

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chinese Geographical Science 2012年第5期22卷 541-549页

作者： GONG Yanming 1 ,HU Yukun 1 ,FANG Fei 1 ,LIU Yanyan 1 ,LI Kaihui 1 ,ZHANG Guangming 2 (1.key laboratory of Biogeography and Bioresource in Arid Land,Xinjiang Institute of Ecology and Geography,chinese {3. of sciences,Urumqi 83.011,china 2.state key laboratory of Vegetation and Environmental Change, Institute of Botany,chinese {3. of sciences,beijing 100093.china) 1. key laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China 2. state key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This study was carried out in the Gurbantünggüt Desert,Uygur Autonomous Region of Xinjiang,Northwest china in August,*** quantify the storage,contribution and vertical distribution patterns of plant biomass carbon (PBC)and soil organic carbon(SOC)in the study area,we investigated the carbon concentrations and its vertical distribution in three different desert shrubland communities dominated by Reaumuria soongorica,Haloxylon ammodendron+*** and Tamarix ramosissima+***,*** analyzed vertical distribution of root biomass carbon and soil carbon contents by excavating soil profiles for each dominated *** results show that SOC is considerably the larger carbon pool in the soil layers of 1.0-3.0 m(the mean value of three shrubland communities is 3..46%)and 3.0-5.0 m(the mean value is 40.24%).In contrast,70.74%of belowground biomass carbon storage in 0-1.0 m layer,and its content decrease with increasing soil *** Haloxylon ammodendron+R. soongorica shrubland community has the highest belowground biomass carbon among three selected communities. This study highlights the importance of SOC stored in deep soil layers(lower than 3.0 m from the surface)in arid shrubland communities in the global carbon *** addition,it provides the data support for revealing deep soil solid carbon potential,and offers scientific basis for the further research in the carbon cycle of terrestrial ecosystem.

关键词： shrubland community plant biomass carbon soil organic carbon vertical distribution Gurbantünggüt desert