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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 {2., Jinhua 32.004, china 2.department of Mathematics, Kunming {2. 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 34C2. 74J30 58Z05

Preparation of nanocrystalline BaTiO_3 ceramics

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Science china(Technological Sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2.LI DeJun1,LI JianBao2.WANG XiaoHui3 & LI LongTu3 1 College of Physics and Electronic Information,Tianjin normal university,Tianjin 300387,{2. 2.Materials and Chemical Engineering Institute,Key Laboratory for hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education,hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti,hainan university,Haikou 5702.8,{2. 3 department of Materials Science and Engineering,Tsinghua university,Beijing 100084,{2. College of Physics and Electronic Information Tianjin Normal University Tianjin 300387 China Materials and Chemical Engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan University Haikou 570228 China department of Materials Science and Engineering Tsinghua University Beijing 100084 China

The high-dense nanocrystalline BaTiO3(BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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Wuhan university Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. department of Chemical Engineering, Wuhan university of Technology, Wuhan 430070, Hubei,{2. 2. College of chemistry and Molecular Sciences, Wuhan university, Wuhan 430072. Hubei,{2. Wuhan university of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) Wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

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Science china chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. department of chemistry, Nanjing {2. of Science and Technology, Nanjing 2.0094, china 2. Institute of Chemical Materials, china Academy of Engineering Physics, Mianyang 62.900, china 1. department of chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of Chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

ON THE VARIATIONS OF G_2

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Chinese Annals of Mathematics,Series B 2003年第3期24卷 387-394页

作者： LIU DONG LIN LEI department of Mathematics, East china {2. university, Shanghai 2.0062. china. department of Mathematics, East china {2. university, Shanghai 2.0062. china. department of Mathematics East China Normal University Shanghai 200062 China

In [1], Shen Guangyu constructed several classes of new simple Lie algebras of characteristic 2. which are called the variations of G2. In this paper, the authors investigate their derivation algebras. It is shown that G2.and its variations all possess unique nondegenerate associative forms. The authors also find some nonsingular derivations of ViG for i = 3,4, 5, 6, and thereby construct some left-symmetric structures on Vi G for i = 3,4,5,6. Some errors about the variations of sl(3, F) in [1] are corrected.

关键词： Variation Derivation Associative form Left-symmetric structure

The generalized Roper-Suffridge extension operator in Banach spaces (Ⅲ)

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Science china Mathematics 2009年第11期52卷 2432-2446页

作者： ZHU YuCan1 & LIU MingSheng2.1 department of Mathematics,Fuzhou university,Fuzhou 350002.{2. 2.department of Mathematics,South china normal university,Guangzhou 510631,{2. 1. department of Mathematics Fuzhou University Fuzhou 350002 China 2. department of Mathematics South China Normal University Guangzhou 510631 China

Suppose that X is a complex Banach space with the norm ||·|| and n is a positive integer with dim X ≥n≥ 2. In this paper,we consider the generalized Roper-Suffridge extension operator Φn,β2.γ2....,βn+1,γn+1(f)... 详细信息

关键词： Roper-Suffridge extension operator biholomorphic starlike mapping almost spirallike mapping of type β and order α spirallike mapping of type β and order α

Synthesis and Crystal Structure of Dichlorobis[N-(4-hydroxylsalicylidene)3-dimethylaminopropylamine]Ni(II)

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Chinese Journal of Structural chemistry 2003年第5期22卷 544-546页

作者： FENG Yun-Long② (Institute of Physical chemistry, Zhejiang normal {2., Jinhua 32.004, china) Zhejiang normal Univ Inst Phys Chem Jinhua 321004 Peoples R China

The title complex, C2.H36Cl2.4NiO4, crystallizes in the monoclinic system, space group P2./c with a = 15.048(3), b = 6.578(1), c = 14.405(3) ? b = 103.03(3), V = 1389.2.5) ?, Z = 2. Mr = 574.18, F(000) = 604, Dc = 1.373 g/cm3 and m(MoKa) = 0.92. mm-1. The structure was refined to R = 0.0337 and wR = 0.0954 for 2.81 observed reflections (I > 2.(I)). The coordination environment around the Ni atom is a distorted NiN2.2.square-plane composed of two nitrogen and two oxygen atoms from the neutral Schiff base ligand of N-(4-hydroxylsalicylidene)-3-dimethyl- aminopropylamine

关键词： nickel complex N,N-dimethylaminopropylamine Schiff base crystal structure

AN EXTREMAL APPROACH TO BIRKHOFF QUADRATURE FORMULAS

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Journal of Computational Mathematics 2001年第5期19卷 459-466页

作者： Ying-guang Shi (department of Mathematics, Hunan normal {2., Changsha 410081, china) 湖南师范大学湖南长沙 410081

Discusses an extremal problem with Birkhoff interpolation constraints. Quadrature formula derived from an extremal problem; Overview of auxiliary lemmas; Derivation of some properties of polynomials.

关键词： an extremal approach Birkhoff quadrature formulas

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical Physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2.1 department of Physics,Zhejiang normal {2.,Jinhua 32.004,china2.Physics department,Shanghai Jiao Tong {2.,Shanghai 2.0030,china Physics department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2.1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution