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Image interpretation of weak-coupling N-mer adsorbate's STM system

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Chinese science Bulletin 1997年第5期42卷 371-374页

作者： HUANG Xintang, Ql Shouren, LI Xinjiao and LI Yongping1 department of Physics, Central china Normal {2., Wuhan 430070, china department of Solid State Electronics, Huazhong {2. of science and technology, Wuhan 430074, china 2. department of Physics, university of science and technology of china, hefei 2.002., china department of Physics Central China Normal University Wuhan China department of Solid State Electronics Huazhong University of Science and Techndogy Wuhan China department of Physics University of Science and Technology of China Hefei China

Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992. Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-

关键词： weak-coupling N-mer adsorbates STM image interpretation exciton dynamics method.

Effects of radial velocity on line profiles and images from the standard thin disk

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 155-162页

作者： PAN CaiJuan department of Physics and Telecommunication Engineering, Baise university, Baise 533000,{2. Center for Astrophysics, university of science and technology of china, hefei 2.0051,{2. 1. department of Physics and Telecommunication Engineering Baise University Baise 533000 China2. Center for Astrophysics University of Science and Technology of China Hefei 230051 China

This paper has derived the general formulae of observed line profiles based on the effects of radial velocity on the standard thin disk fluid around a rotating black hole. Through the ray-tracing method the line profiles of different parameters have been calculated. Comparison of the line profiles with and without a radial velocity shows that the effects of radial velocity on line profiles cannot be neglected in most cases. In both cases the accretive disk imaging shape remains unchanged.

关键词： standard thin disk radial velocity Kerr metric line flux

ATOMIC FORCE MICROSCOPY STUDIES OF POLYCAPROLACTONE RINGED SPHERULITES

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Chinese Journal of Polymer science 2000年第6期18卷 569-572页

作者： Jian-bin Zhang De-zhu Ma Hua Zhong Xiao-lie Luo department of Polymer science and Engineering,{2., hefei 2.002., china Univ Sci & Technol china Dept Polymer Sci & Engn Hefei 230026 Peoples R China

The surface morphology of free-surface PCL ringed spherulites was investigated by using atomic force microscopy. The spherulites were obtained by crystallization of PCL/PVC blends of different compositions. It was found that the ringed spherulite exhibited regularly fluctuating rings on its surface. Compared with the bright-dark ring pattern of the spherulite under a polarizing microscope, it was proved that the optical characteristics of the ringed spherulite under polarizing microscope coincided with its surface characteristics. The bright rings in polarizing micrographs of the spherulite coincided with the convex rings on its surface, while the dark rings coincided with the concave rings.

关键词： AFM surface morphology ringed spherulites PCL/PVC blends

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,{2., 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

Norm continuity for t>0 of linear operator families

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Chinese science Bulletin 1998年第9期43卷 719-723页

作者： LIANG Jin and XIAO Tijun department of Mathematics, university of science and technology of china,{2., china department of Mathematics University of Science and Technology of China Hefei China

Some criteria of norm continuity for t>0 of linear operator families in Hilbert spaces are given.

关键词： linear operator family norm continuity criteria.

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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science china Chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2.& HU Weixiao1 1. department of Pharmaceutical science, Zhejiang {2. of technology, Hangzhou 310032. china 2. department of Applied Chemistry, Zhejiang Institute of science and technology, Hangzhou 310033, china 1. department of Pharmaceutical science Zhejiang University of Technology 310032 Hangzhou China 2. department of Applied Chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

Hamiltonian Formalism of de-Sitter Invariant Special Relativity

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Communications in Theoretical Physics 2007年第7期48卷 27-36页

作者： YAN Mu-Lin XIAO Neng-Chao HUANG Wei Interdisciplinary Center for Theoretical Study,university of science and {2. of china,hefei 2.002.,chinaLI Si department of Mathematics,university of science and {2. of china,hefei 2.002.,china Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China department of Mathematics University of Science and Technology of China Hefei 230026 China

The Lagrangian of Einstein's special relativity with universal parameter c(SR_c)is invariant under Poincarétransformation,which preserves Lorentz metric η_μν.The SR_c has been extended to be one which is invariant underde Sitter transformation that preserves so-called Beltrami metric B_(μv).There are two universal parameters,c and R,inthis Special Relativity(denoted as SR_(cR)).The Lagrangian-Hamiltonian formulism of SR_(cR) is formulated in this *** canonic energy,canonic momenta,and 10 Noether charges corresponding to the space-time's,de Sitter symmetryare *** canonical quantization of the mechanics for SR_(CR)-free particle is *** physics related to itis discussed.

关键词： de-Sitter invariance special relativity canonic energy and canonic momenta Beltrami metric

Formation of hyperbranched polymers in atom transfer radical copolymerization of MMA and DVB

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science china Chemistry 2010年第12期53卷 2440-2451页

作者： SUN Miao & PAN CaiYuan CAS Key Laboratory of Soft Matter Chemistry department of Polymer science and Engineering,{2. of science and technology of china,hefei 2.002.,china 1. CAS Key Laboratory of Soft Matter Chemistry department of Polymer science and Engineering University of Science and Technology of China Hefei 230026 China

Hyperbranched poly(methyl methacrylate)s (HPMMAs) have been successfully prepared by atom transfer radical copolymerization of MMA and divinylbenzene (DVB).Kinetic study shows complete consumption of the initiator in 0.5 h,and relatively low polymerization rate when DVB content in the feed was *** analyzing MALDI-TOF spectra of the resulting copolymers,the linear A n B (n=0,1,2.3) oligomers were formed in 0.5 h of polymerization,and then the oligomers reacted each other to form dimers,further reactions produced *** SEC and NMR spectroscopies were used to trace the polymerization,and the results demonstrate that small amount of the branching reactions occur in the initial polymerization,and the branched polymers are significantly generated past a certain conversion depending upon the feed *** the content of DVB in the monomer mixture can increase the pendent vinyl groups of the linear oligo-inimers,leading to gelation at low MMA conversion.

关键词： atom transfer radical polymerization branching divinylbenzene hyperbranched polymers mechanism

Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application science and technology, Harbin {2. of science and technology, Harbin 150080, china 2. department of Precision Instruments, Tsinghua {2., Beijing 100084, china) School of Application science and technology Harbin University of Science and Technology Harbin 150080 China department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.