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RHEOLOGICAL BEHAVIOR OF EPOXY RESIN WATERBORNE DISPERSIONS

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chinese Journal of Polymer Science 2001年第5期19卷 471-476页

作者： Zhen-zhong Yang Yuan-ze Xu De-lu Zhao State Key laboratory of Polymer physics & Chemistry, Center for Molecular Science Institute of Chemistry, chinese academy of sciences, Beijing {3. china chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Ctr Mol Sci Beijing 100080 Peoples R China

The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique. Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.

关键词： epoxy resin waterborne dispersion rheological behavior cluster-cluster aggregation percolation transition

A Series of Soliton-like and Double-like Periodic Solutions of a (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Vesselov Equation

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Communications in Theoretical physics 2004年第11期42卷 655-660页

作者： CHEN Yong,~(1,3.4, WANG Qi~(2,4) LI Biao~(2,4) ~1Department of Mathematics,Ningbo University,Ningbo 3.5211,china ~2Department of Applied Mathematics,Dalian University of Technology,Dalian 116024,china ~3.epartment of physics,Shanghai Jiao Tong University,Shanghai 20003.,china ~4Key laboratory of Mathematics Mechanization~ the chinese academy of sciences,Beijing 100080,china Key laboratory of Mathematics Mechanization the Chinese Academy of Sciences Beijing 100080 China

We generalize the algebraic method presented by Fan [***.A:***.3. (2003. 7009)] to uniformlyconstruct a series of soliton-like solutions and double-llke periodic solutions for nonlinear partial differential equations(NPDE),As an application of the method,we choose a (2+1)-dimensional asymmetric Nizhnik-Novikov-Vesselov equa-tion and successfully construct new and more general solutions including a series of nontraveling wave and coefficientfunctions’ soliton-like solutions,double-like periodic and trigonometric-like function solutions.

关键词： symbolic computation soliton-like solution Weierstrass and Jacobi elliptic functions periodic solution

A statistical study of the relation between soft X-ray excess and accretion disk

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 102-105页

作者： LIU JieYing1,2,3.& QIAO ErLin1,2 1 National Astronomical Observatories/Yunnan Observatory,chinese academy of Science,Kunming 650011,china 2 Key {3. for the Structure and Evolution of Celestial Objects,chinese academy of sciences,Kunming 650011,china 3.Graduate University of chinese academy of sciences,Beijing 100049,china 1. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Science Kunming 650011 China 2. Key laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China 3. Graduate University of chinese academy of sciences Beijing 100049 China

To study the origin of the soft X-ray excess,we compile a sample of 94 unobscured,radio-quiet QSOs and Seyfert galaxies with available data from GALEX and *** find that 50 sources show strong soft X-ray excess and the other 44 show weak/no soft X-ray *** analyses of the data indicate that the difference in soft X-rays is mainly but not only resulting from different accretion rates(in units of Eddington rate).The statistical study of the sources with soft X-ray excess shows that the strength of soft X-ray excess weakly and positively correlates with the Eddington ratio and increases with the increase of the strength of UV radiations relative to the *** that the UV emissions are from the thin disk,the correlations imply that the origin of soft X-ray excess is associated with the thin disk,either by means of Comptonization of the disk photons or in some other ways.

关键词： accretion:accretion disks ultraviolet:galaxies X-rays:galaxies

Diffuse interstellar absorption bands

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Science china(physics,Mechanics & Astronomy) 2009年第4期52卷 489-501页

作者： XIANG FuYuan1,2,LIANG ShunLin2 & LI AiGen2,3.1 Faculty of Materials,Photoelectronics and physics,Xiangtan University,Xiangtan 411105,china 2 Department of physics and Astronomy,University of Missouri,Columbia,MO 65211,USA 3.Purple Mountain Observatory,{3.,Nanjing 210008,china 1. Faculty of Materials Photoelectronics and Physics Xiangtan University Xiangtan 411105 China 2. Department of physics and Astronomy University of Missouri Columbia MO 65211 USA 3. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

关键词： astrophysics interstellar matter interstellar extinction diffuse interstellar band circumstellar environment

Electron dynamics in collisionless magnetic reconnection with a PIC simulation

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chinese Science Bulletin 2009年第3期54卷 456-460页

作者： GUO Jun1,2 1 School of Mathematics and physics, Qingdao University of Science and Technology, Qingdao 266042, china 2 State Key laboratory of Space Weather, {3., Beijing 100080, china School of Mathematics and physics Qingdao University of Science and Technology Qingdao China State Key laboratory of Space Weather Chinese Academy of Sciences Beijing China

Two-dimensional particle-in-cell (PIC) simulation is used to investigate electron dynamics in colli- sionless magnetic reconnection, and the proton/electron mass ratio is taken to be mi /me = 256. The results show that the presence of a strong initial guide field will change the direction of the electron flow. The electron density cavities and the parallel electric field can be found in the electron inflow re- gion along the separatrix, and the electron inflow and density cavities only appear in the second and fourth quadrants. What is different from the results with a smaller mass ratio is that new structures appear in the diffusion region near the X line: (1) Narrow regions of density enhancement and density cavities can be found synchronously in this region; and (2) corresponding to the electron density changes near the X line, the strong parallel electric fields are found to occur in the first and third quadrants. These electric fields perhaps play a more important role in acceleration and heating electrons than those fields located in the density cavities.

关键词： PIC模仿磁链接导向场电子动力学

Charmed Baryon in Diquark Model

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原子核物理评论 2009年第S1期26卷 190-193页

作者： WANG Qing-wu1,3. ZHANG Peng-ming1,2(1 Institute of Modern physics, chinese academy of sciences, Lanzhou 73.000, china 2 Center of Theoretical Nuclear physics, National laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 73.000, china 3.Graduate School of chinese academy of sciences, Beijing 100049, china) Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Graduate School of chinese academy of sciences Beijing 100049China Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China

A diquark model is used to investigate single-charmed baryons. In this model,baryon is composed of two diquarks and an antiquark. Masses of lowest lying states with JP=1/2± are obtained. Baryons in our results are as heavy as other theoretic predictions and we suggest that the five-quark components should be considered in any three-quark model for studying the charmed baryons.

关键词： charm diquark pentaquark

Entropy product measure for multipartite pure states

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Science china(physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2, LIU Dan2, PAN Feng3.& LONG Guilu2,4 1. Department of physics, Chifeng College, Chifeng 024001, china 2. Key laboratory for Quantum Information and Measurements, Department of physics, Tsinghua University, Beijing 100084, china 3. Department of physics, Liaoning Normal University, Dalian 116029, china 4. Key laboratory for Atomic and Molecular Nano-sciences, Tsinghua University, Beijing 100084, china Correspondence should be addressed to Long Guilu Department of physics Chifeng College Chifeng 024001 China Key laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing 100084 China Department of physics Liaoning Normal University Dalian 116029 China Key laboratory for Atomic Molecular Nano-sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2 & JIANG Zonglin2 1. Key laboratory of High Temperature Gas Dynamics, Institute of Mechanics, chinese academy of Sci- ences, Beijing {3., china 2. Graduate University of chinese academy of sciences, Beijing 10003., china 1. Key laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. Graduate University of chinese academy of sciences 100039 Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

TRANSIENT EFFECT OF A BOGER FLUID FLOWING AROUND A CONFINED CYLINDER

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chinese Journal of Polymer Science 2001年第4期19卷 377-384页

作者： Xian-feng Li Huai-tian Bu De-lu Zhao State Key laboratory of Polymer physics and Chemistry Center for Molecular Science,Institute of Chemistry, chinese academy of sciences, Beijing {3., china chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China

This paper is concerned with the numerical simulation of the transient effect of an inertialess Boger flow past a confined circular cylinder and the comparison of predictions with particle image velocimetry (PIV) measurements given by Shiang et al.. Dynamic simulation based on the Oldroyd-B constitutive model was carried out using a Lagrangian-Eulerian algorithm. The evolution of velocity field was obtained for the flow at two Deborah (De) numbers, i.e. De = 1.2 and 3.0. At low De, the flow reached steady state rapidly, and showed a symmetric flow regime. However, at high De, the time required to reach steady flow behind the cylinder increased significantly, and the distribution of the velocity field appears to be asymmetric with respect to the stagnation line. Fairly good agreement between the numerical results and the experimental observations is reported. It can be concluded that both the experimental measurements and the present simulations indicate that the elasticity of the polymeric flow strongly affect the flow regime of viscoelastic flow around a confined cylinder.

关键词： transient effect flow around a cylinder Lagrangian-Eulerian algorithm Oldroyd-B model