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Howe duality in Dunkl superspace

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science china Mathematics 2010年第12期53卷 3153-3162页

作者： REN GuangBin 1,2 1 department of Mathematics, University of science and technology of china, Hefei 230026, china 2 department of Mathematics, University of Aveiro, Aveiro 3810-193, Portugal 1. department of Mathematics University of Science and Technology of China Hefei 230026 China2. Department of Mathematics University of Aveiro Aveiro 3810-193 Portugal

In the framework of superspace in Clifford analysis for the Dunkl version, the Fischer decomposition is established for solutions of the Dunkl super Dirac operators. The result is general without restrictions on multiplicity functions or on super dimensions. The Fischer decomposition provides a module for the Howe dual pair G × osp(1|2) on the space of spinor valued polynomials with G the Coxeter group, while the generators of the Lie superspace reveal the naturality of the Fischer decomposition.

关键词： Dunkl operators superspace Fischer decomposition Dirac operator

Energy dispersion of complex non-isolated vortices

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Chinese science Bulletin 2011年第25期56卷 2713-2717页

作者： LUO ZheXian 1,2 1 Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information science and technology, Nanjing 210044, china 2 Wuxi Research Center of environmental science and technology, Wuxi 214031, china Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Wuxi Research Center of environmental science and technology

Energy dispersion is a fundamental scientific problem in the study of natural disasters such as typhoons, heavy rain and earthquakes. The problem has been addressed by both multi-discipline research and forecast studies. The dynamics of isolated circular vortex energy dispersion have been solved. However, the disastrous results of typhoons and heavy rain often occur due to non-isolated circular vortices, the dynamics of which are explored in this paper. The energy dispersion characteristics of non-isolated vortices with complex structural patterns are examined using a linearized nondivergent barotropical vorticity equation model. In the initial field, a tropical cyclone (TC) vortex and a meso-scale vortex coexist, forming a complex structural pattern. An analytic solution based on a Fourier transform and simulations using a two-dimensional model show the following. (1) A wave train of TC-G-D may be created by the energy dispersion where the line connecting the three member centers of the wave train is parallel to the x axis in the case of an initial TC vortex without a meso-scale vortex. (2) A wave train of TC-G-D may also be created by energy dispersion. However, the line connecting the three member centers of the wave train would no longer be parallel to the x axis. Instead, they would form a triangle in the presence of the initial TC vortex with the meso-scale vortex. (3) There is a nonlinear relationship between the initial intensity of the meso-scale vortex and the base angle of the triangle. These results have the potential to be applied in the field of typhoon forecasting.

关键词：能量色散非隔离式旋涡非线性关系中尺度涡台风预报结构模式傅立叶变换

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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science china(Technological sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2,YANG Mo1 & XU PeiWei2 1 College of Power Engineering,University of Shanghai for science and technology,Shanghiai 200093,china 2 department of environmental Engineering,Jilin Architectural and Civil Engineering Institute,Changchun 130021,china 1. College of Power Engineering University of Shanghai for Science and Technology Shanghiai 200093 China2. Department of Environmental Engineering Jilin Architectural and Civil Engineering Institute Changchun 130021 China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

SYNTHESIS AND CHARACTERIZATION OF FOUR-ARMED BLOCK POLY(STYRENE-b-p-NITROPHENYL METHACRYLATE)PREPARED BY THE ATRP METHOD

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Chinese Journal of Polymer science 2002年第4期20卷 353-360页

作者： Cai-yuan Pan Lei Tao Ye Liu department of Polymer science and Engineering University of science and technology of china, Hefei 230026 china department of Polymer science and Engineering University of Science and Technology of China Hefei 230026

A novel tetrafunctional initiator, C [CH_2O (CH_2)_3 OOCCH(Br)CH_3]_4 (1), was synthesized through the reaction oftetraol with α-bromopropionyl chloride, and then was used as initiator of atom transfer radical polymerization (ATRP) in thepreparation of 4-armed polystyrene (PSt) with narrow polydispersity. The structure, molecular weight and molecular weightdistribution (MWD) of each arm were studied by ~1H-NMR and GPC data of hydrolyzed products of the 4-armed PSt. TheATRP of St using 1/CuBr/bpy as initiator system is of 'living' character based on the following evidence: narrow MWD,constant concentration of chain radical during the polymerization, control of molecular weight by the molar ratio of monomerconsumed to 1. The 4-armed poly(St-b-p-nitrophenyl methacrylate) [poly(St-b-NPMA)] was prepared by the ATRP ofNPMA using 4-armed PSt with terminal bromine as the initiator, and characterized by FT-IR, ~1H-NMR spectra and GPCcurves. The micelles with PSt as core, and PNPMA as shell were formed by dropping DMSO into a solution of 4-armedpoly(St-b-NPMA) in DMF, as proved by laser light scatter (LLS) method.

关键词： Tetrafunctional initiator Atom transfer radical polymerization 4-Armed polystyrene 4-Armed poly(styrene-b-pnitrophenyl methacrylate) Unimolecular micelles

Effects of NaNbO_3-Co_2O_3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of Wuhan University of technology(Materials science) 2007年第4期22卷 722-724页

作者：邓毅华 College of Material science and Engineering South China University of Technology department of Electronic science and technology Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2O3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2O3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

Changes of microbial community structures and functional genes during biodegradation of phenolic compounds under high salt condition

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Journal of environmental sciences 2009年第6期21卷 821-826页

作者： WANG Ping,QU Yuanyuan,ZHOU Jiti School of environmental and Biological science and technology,Dalian University of technology,Dalian 116024,china. [a]School of environmental and Biological science and technology Dalian University of Technology Dalian 116024 China

The changes of microbial community structures and functional genes during the biodegradation of single phenol and phenol plus p-cresol under high salt condition were *** was found that the phenol-fed system（PFS） exhibited stronger degrading abilities and more stable biomass than that of the phenol plus p-cresol-fed system（PCFS）.The microbial community structures were revealed by a modern DNA fingerprint technique,ribosomal intergenic spacer analysis（RISA）.The results indicated that the microbial community of PFS changed obviously when gradually increased phenol concentration,while PCFS showed a little change.16S rRNA sequence analysis of the major bands showed that Alcanivorax *** was predominant species during phenolic compounds ***,amplified functional DNA restriction analysis（AFDRA） on phenol hydroxylase genes showed that the fingerprints were substantially different in the two systems,and the fingerprints were not the same during the different operational periods.

关键词： phenolic compounds high salt phenol hydroxylase ribosomal intergenic spacer analysis amplified functional DNArestriction analysis

Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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science china(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2 1 department of Materials science and Engineering,Nanjing University of science and technology,Nanjing 210094,china 2 College of Materials science and Engineering,Southeast University,Nanjing 211189,china 1. department of Materials science and Engineering Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Bifurcations of travelling wave solutions for two generalized Boussinesq systems

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science china Mathematics 2008年第9期51卷 1577-1592页

作者： LI JiBin1,2 1 department of Mathematics, Zhejiang Normal University, Jinhua 321004, china 2 department of Mathematics, Kunming University of science and technology, Kunming 650093, china department of Mathematics Zhejiang Normal University Jinhua 321004 China department of Mathematics Kunming University of Science and Technology Kunming 650093 China

Using the methods of dynamical systems for two generalized Boussinesq systems, the existence of all possible solitary wave solutions and many uncountably infinite periodic wave solutions is obtained. Exact explicit parametric representations of the travelling solutions are given. To guarantee the existence of the above solutions, all parameter conditions are determined.

关键词： nonlinear wave bifurcation solitary wave exact explicit solution generalized Boussinesq system 34C37 34C23 74J30 58Z05

Exact eigenstates for a class of models describing multiphoton processes in the presence of seven bosonic modes

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science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 649-657页

作者： ZHAN Zhiming1,LI Weibin2,YOU Jun2,XIE Xiaotao2 & YANG Wenxing2 1.State Key Laboratory of Laser technology,Huazhong University of science and technology,Wuhan 430074,china 2.department of Physics,Huazhong University of science and technology,Wuhan 430074,china 1. State Key Laboratory of Laser technology Huazhong University of Science and Technology 430074 Wuhan China 2. department of Physics Huazhong University of Science and Technology 430074 Wuhan China

We present the analytical expressions of eigenstates and eigenenergies by using a parameter λ without the assumption of Bethe anzatz for three kinds of seven-bosonic-mode mixing models. The parameter is shown to be determined by the roots of a simple polynomial. We also demonstrate the exact analytical expressions of eigenstates and energies without any unknown parameter.

关键词： spectra, eigenstate, eigenvalue.