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Accuracy of Multivariable Refinable Functions and Two-Scale Similarity Transform

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Acta Mathematica Sinica,English Series 2000年第2期16卷 271-276页

作者： Qiuhui Sheng Silong Peng institute of Mathematics,academy of Mathematics and Systems {2.,chinese academy of {2.,beijing 100080,P.R.china institute of Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 P. R. China

In this paper,we prove that if two multiresolutions satisfy a relation,then they have the same accuracy in the multivariate FSI case.

关键词： Accuracy Symbol function Two-scale similarity transform

COPOLYMERIZATION OF ETHYLENE AND PROPYLENE WITH (CpCH_2.H_2.H=CH_2._2.Cl_2.M=Zr,Hf)AND Cp_2.rCl_2.CATALYSTS

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chinese Journal of Polymer Science 2000年第2期18卷 169-175页

作者： Hui Yao Shi-jing Xiao institute of Chemistry, chinese academy of sciences,{2., china chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

(CpCH_2.H_2.H = CH_2._2.Cl_2.M=Zr, Hf)/MAO and Cp_2.rCl_2.MAO (Cp=cyclopentadienyl; MAO=methylaluminoxane) catalyst systems have been compared for ethylene copolymerization to investigate the influence of theligand and transition metal on the polymerization activity and copolymer properties. For both CH_2.H_2.H=CH_2.substitutedcatalysts the catalytic activity decreased with increasing propene concentration in the feed. The activity of the hafnocenecatalyst was 6～8 times lower than that of the analogous zirconocene catalyst, ^(13)C NMR analysis showed that the copolymerobtained using the unsubstituted catalyst Cp_2.rCl_2.has greater incorporatien of propene than those produced byCH_2.H_2.H=CH_2.substituted Zr and Hf catalysts. The melting point, crystallinity and the viscosity-average molecularweight of the copolymer decreased with an increase of propenc concentration in the feed. Both CH_2.H_2.H= CH_2.substitutedZr and Hf catalysts exhibit little or no difference in the melting point and crystallinity of the produced copolymers. However,there are significant differences between the two zirconocene catalysts. The copolymer produced by Cp_2.rCl_2.catalyst havemuch lower T_m and X_c than those obtained with the (CpCH_2.H_2.H=CH_2._2.rCl_2.catalyst. The density and molecular weightof the copolymer decreased in the order: (CpCH_2.H_2.H=CH_2._2.fCl_2.(CpCH_2.H_2.H=CH_2._2.rCl_2.Cp_2.rCl_2. The kineticbehavior of copolymerizaton with Hf catalyst was found to be different from that with Zr catalyst.

关键词： Metallocene catalyst Ethylene/propylene copolymerization Methylaluminoxane

Single-molecule studies of DNA by molecular combing

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Progress in Natural Science:Materials International 2007年第5期17卷 493-499页

作者： Liu Yuying, Wang Pengye and Dou Shuoxing (College of Science, china Agricultural University, beijing 100083, china Laboratory of Soft Matter physics, beijing National Laboratory for Condensed Matter physics, institute of physics, chinese academy of sciences, beijing 100080, china) [a]College of Science China Agricultural University Beijing China [b]Laboratory of Soft Matter physics Beijing National Laboratory for Condensed Matter PhysicsInstitute of Physics Chinese Academy of Sciences Beijing China

Molecular combing is a powerful method for aligning a large array of DMA molecules onto a surface. It is a process whereby DNA molecules are stretched and aligned on a glass surface by the force via fluid flow. The ability to comb up to several hundred DNAs on a single cover slip allows for a statistically significant number of measurements to be made. These features make molecular combing an attractive tool for genomic studies, such as DNA replication, DNA transcription, DNA-protein interaction and so on. In this review article, we discuss the molecular combing principle, method and its applications.

关键词： DNA molecule molecular combing DNA-protein interaction.

Wet-chemical synthesis and characteristics of Au nanoshell

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Science china Chemistry 2005年第5期48卷 431-435页

作者： LIU Zhongxin1,2. SONG Hongwei1, YU Lixin1,2. YANG Linmei1,2.& PAN Guohui1,2.1. Key Laboratory of Excited State physics, Changchun institute of Optics, Fine Mechanics and physics, chinese academy of sciences, Changchun 130033, china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 1. Key Laboratory of Excited State physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 2. nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 30℃ (5 W/cm2. irradiation area was 2.cm2.. This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.

Wandering domains in the transcendental dynamics

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chinese Science Bulletin 2001年第1期46卷 34-35页

作者： WANG Yuefeiinstitute of Mathematics, chinese academy of sciences,{2., china institute of Mathematics Chinese Academy of Sciences Beijing China

It is shown that new classes of non-critically finite entire functions do not have wandering domains.

关键词： iteration Fatou set Julia set wandering domains.

Input function and simulated distributions of tritium in the North Pacific

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Science china Earth sciences 2010年第3期53卷 441-453页

作者： BA Qi1,2.& XU YongFu1 1 State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry, institute of Atmospheric physics, chinese academy of sciences, beijing 10002., china 2.Graduate University of chinese academy of sciences, beijing 100049, china 1. State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 47 years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 30°N–40°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

关键词： North Pacific basin-wide ocean general circulation model tritium input function tritium distributions

Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation

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Science china(Technological sciences) 2005年第z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2.& J. G. Wang3 1. institute of Mechanics, chinese academy of sciences,{2., china 2. Graduate School, chinese academy of sciences, beijing 100060, china 3. Tropical Marine Science institute, National University of Singapore, Singapore 1192.0 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

Simulation of the future change of East Asian monsoon climate using the IPCC SRES A2.and B2.scenarios

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chinese Science Bulletin 2003年第10期48卷 1024-1030页

作者： BUEH Cholaw LASG, institute of Atmospheric physics,{2., beijing 10002., china LASG Institute of Atmospheric Physics Chinese Academy of Sciences China

In this paper, we applied the newest emission scenarios of the sulfur and greenhouse gases, i.e. Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES) A2.and B2.scenarios, to investigating the change of the East Asian climate in the last three decades of the 2.st century with an atmosphere-ocean coupled general circulation model. The global warming enlarges the land-sea thermal contrast and, hence, enhances (reduces) the East Asian summer (winter) monsoon circulation. The precipitation from the Yangtze and Huaihe river valley to North china increases significantly. In particular, the strong rainfall increase over North china implies that the East Asian rainy area would expand northward. In addition, from the southeastern coastal area to North china, the rainfall would increase significantly in September, implying that the rainy period of the East Asian monsoon would be prolonged about one month. In July, August and September, the interannual variability of the precipitation enhances evidently over North china, meaning a risk of flooding in the future.

关键词：模拟亚洲东方季风气侯变化大气循环模型

Concatenating construction of the multisymplectic schemes for 2.1-dimensional sine-Gordon equation

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Science china Mathematics 2004年第1期47卷 18-30页

作者： WANG Yushun, WANG Bin & QIN MengzhaoLASG, institute of Atmospheric physics,{2., beijing 10002., china School of Mathematics and Computer Science, Nanjing Normal University, Nanjing 2.0097, china School of Mathematics and System Science,{2., beijing 100080, china 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China 2. School of Mathematics and Computer Science Nanjing Normal University 210097 Nanjing China 3. School of Mathematics and System Science Chinese Academy of Sciences 100080 Beijing China

In this paper, taking the 2.1-dimensional sine-Gordon equation as an example, we present the concatenating method to construct the multisymplectic schemes. The method is to discretizee independently the PDEs in different directions with symplectic schemes, so that the multisymplectic schemes can be constructed by concatenating those symplectic schemes. By this method, we can construct multisymplectic schemes, including some widely used schemes with an accuracy of any order. The numerical simulation on the collisions of solitons are also proposed to illustrate the efficiency of the multisymplectic schemes.

关键词： 2.l-climensional sine-Gordon equation multisymplectic scheme concatenating method solitons