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GLOBAL EXISTENCE AND ASYMPTOTIC BEHAVIOR FOR AN 1-D COMPRESSIBLE ENERGY TRANSPORT MODEL

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Acta Mathematica Scientia 2009年第5期29卷 1295-1308页

作者：黎勇 college of applied science Beijing University of Technology

In this article, the global existence and the large time behavior of smooth solutions to the initial boundary value problem for a degenerate compressible energy transport model are established.

关键词： degenerate parabolic system hyperbolic-parabolic energy transport model large time behavior

RELAXATION TIME LIMITS PROBLEM FOR HYDRODYNAMIC MODELS IN SEMICONDUCTOR science

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Acta Mathematica Scientia 2007年第2期27卷 437-448页

作者：黎勇 college of applied science Beijing University of technology

In this article, two relaxation time limits, namely, the momentum relaxation time limit and the energy relaxation time limit are considered. By the compactness argument, it is obtained that the smooth solutions of the multidimensional nonisentropic Euler-Poisson problem converge to the solutions of an energy transport model or a drift diffusion model, respectively, with respect to different time scales.

关键词： Hydrodynamic models nonisentropic Euler-Poisson momentum relaxation time limit energy relaxation time limit

Multi-wavelength continuous-wave Nd:YVO4 self-Raman laser under in-band pumping

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Chinese Physics B 2019年第8期28卷 184-189页

作者： Li Fan Xiao-Dong Zhao Yun-Chuan Zhang Xiao-Dong Gu Hao-Peng Wan Hui-Bo Fan Jun Zhu college of Physics science and technology Institute of Applied Photonic Technology Yangzhou University

Multi-wavelength continuous-wave self-Raman laser with an a-cut composite YVO4/Nd:YVO4/YVO4 crystal pumped by an 879-nm wavelength-locked laser diode is demonstrated for the first ***-wavelength Raman lasers at 1168.4,1176,1178.7,and 1201.6 nm are achieved by the first Stokes shift of the multi-wavelength fundamental lasers at 1064,1066.7,1073.6,1084,and 1085.6 nm with two Raman shifts of 890 and 816 cm^-1.A maximum Raman output power of 2.56 W is achieved through the use of a 20-mm-long composite crystal,with a corresponding optical conversion efficiency of 9.8%.The polarization directions of different fundamental and Raman lasers are investigated and found to be orthogonalπandσ*** orthogonally polarized multi-wavelength lasers with small wavelength separation pave the way to the development of a potential laser source for application in spectral analysis,laser radar and THz generation.

关键词： multi-wavelength continuous-wave self-Raman laser in-band pumping

Combined experimental and theoretical study on the effect of Nb content on martensitic transformation of NbRu shape memory alloys

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Chinese Physics B 2010年第3期19卷 426-431页

作者：谭昌龙蔡伟田晓华 college of applied science Harbin University of Science and Technology School of Materials science and Engineering Harbin Institute of Technology

The effect of Nb content on the martensitic transformation of NbRu high-temperature shape memory alloys is investigated by experiments and first-principles calculations. We calculate the lattice parameters, density of states, charge density, and heats of formation of Nb50＋xRu50-x βphase. The results show that an increase in Nb content increases the stability of Nbso＋xRu50-x β phase, leading to a significant decrease of the β to β ′martensitic transformation temperature. In addition, the mechanism of the effects of Nb content on phase stability and martensitic transformation temperature is studied on the basis of electronic structure.

关键词： high-temperature shape memory alloy NbRu electronic structure martensitic transformation

Influences of Mg^(2+) ion on dopant occupancy and upconversion luminescence of Ho^(3+) ion in LiNbO_3 crystal

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Chinese Physics B 2013年第9期22卷 399-402页

作者：代丽徐超张颖李大勇徐玉恒 School of Materials science and Engineering Harbin University of Science and Technology applied science college Harbin University of Science and Technology Department of the applied Chemistry Harbin Institute of Technology

The effects of a Mg^2＋ ion on the dopant occupancy and upconversion luminescence of a Ho^3＋ ion in LiNbO3 crystal are reported. The birefringence gradient of the crystal is measured to investigate the optical homogeneity. The X-ray powder diffraction spectrum and the upconversion luminescence are used to investigate defect structure and spectroscopic properties of Mg,Ho：LiNbO3. Under 808-nm excitation, blue, red, and very intense yellow-green bands are observed. Based on the energy levels of Ho^3＋ in LiNbO3, and the pump intensity dependence of the observed emission, an excitation scheme is presented. The upconversion emission spectra reveal an enhancement of upconversion intensity when the Mg^2＋ ions are introduced into Ho：LiNbO3. The main upconversion mechanism is discussed in this work.

关键词： Mg,Ho:LiNb03 upconversion luminescence optical homogeneity

Partial Hydrolysis of the Fucosylated Chondroitin Sulfate from Sea Cucumber Isostichopus badionotus and Its Mechanism

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Chinese Journal of Structural Chemistry 2012年第10期31卷 1455-1463页

作者：陈士国李国云叶兴乾薛长湖 college of Biosystem Engineering and food science Zhejiang University college of food science and technology Ocean University of China

The method for preparing low molecular weight fucosylated chondroitin sulfate from sea cucumber lsostichopus badionotus using partial acid hydrolysis was reported, and its hydrolysis mechanism was also investigated. The sea cucumber chondroitin sulfate FCS was hydrolyzed under different conditions （80℃3 h and 6 h）, then isolated and purified on a Bio-P-4 geltration to prepare low molecular weight fractions （LMWF-FCS）. The chemical compositions of LMWF-FCS showed the branched fucose （Fuc） was cleaved during acid hydrolysis process, whereas the mole ratio of acetyl-galactosamine （GalNAc） and glucuronic acid （GlcA） in the backbone remained the same, which indicated the backbone was a typical chondroitin sulfate structure. The disaccharide composition analysis of LMWF-FCS suggested that the sulfation patterns of GalNAc in the backbone chain changed and the substitution value was reduced. Furthermore, the 1D NMR analysis illustrated the branched-Fuc was cleaved during acid hydrolysis, but their substitution patterns were not influenced, which was distinct from the previous reports that the substitutions of branched-Fuc in FCS were easy to change. Simultaneously, the sulfation pattern of GalNAc in backbone chain changed obviously in the acid hydrolysis process. The anticoagulant activity in vitro illuminated the anticoagulant activity of the degradation products over time in the acid hydrolysis are gradually declined, but still kept good. Therefore, the LMWF-FCS prepared could be developed as a new anticoagulant and antithrombotic drug like low molecular weight heparin.

关键词： sea cucumber chondroitin sulfate NMR partial acid hydrolysis anticoagulant

Copper-catalyzed N-arylation of 2-arylindoles with aryl halides

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Chinese Chemical Letters 2014年第9期25卷 1240-1243页

作者： Wei Liu Li-Ya Han Rui-Li Liu Li-Ge Xu Yan-Lan Bi college of food science and technology Henan University of Technology

10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-... 详细信息

关键词： 2-Arylindoles Aryl halides N-Arylation Copper

Calculations of state-selective differential cross sections for charge transfer in collisions between O^(3+) and H_2

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Chinese Physics B 2008年第8期17卷 2890-2896页

作者：迟宝倩刘玲王建国 college of science Shenyang Science and Technology University Institute of applied Physics and Computational Mathematics

The non-dissociative charge-transfer processes in collisions between O^3＋ and H2 are investigated by using the quantum-mechanical molecular-orbital coupled-channel （QMOCC） method. The adiabatic potentials and radial coupling matrix elements utilized in the QMOCC calculations are obtained with the spin-coupled valence-bond approach. Electronic and vibrational state-selective differential cross sections are presented for projectile energies of 0.1, 1.0 and 10.0eV/u in the H2 orientation angles of 45° and 89°. The electronic and the vibrational state-selective differential cross sections show similar behaviours： they decrease as the scattering angle increases, and beyond a specific angle the oscillating structures appear. Moreover, it is also found that the vibrational state-selective differential cross sections are strongly orientation-dependent, which provides a possibility to determine the orientations of molecule H2 by identifying the vibrational state-selective differential scattering processes.

关键词： charge transfer molecular-orbital coupled-channel method infinite-order sudden ap-proximation state-selective differential cross sections

EB XML Modeler and SMART XML Storage Theory

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电工技术学报 2014年第S1期29卷 149-154页

作者： Qu Xiao Cai Weijian Lü Shuqiang Zhejiang University of science & technology college of applied Arts and science Beijing Union University

Current electronic business activities involve a vast number of trading partners and different electronic *** different enterprises use different document *** is the well-understood problem of the lack of information interoperability between applications in the e-business *** is required to construct an enterprise information model to harmonize different system data structures into a unified data *** purpose of this paper is to develop an E-Business information modeler,which will be a good tool to exchange the information between different business *** is a new approach to the well-understood problem of the lack of information interoperability between applications in the e-business *** will be a more flexible and interoperable way of standardizing Business *** the transformation,SMART theory is widely used in our *** is meta-model to formally specify information structures in object *** provides an object-oriented environment to express the canonical information model with one semantic structure,that is,*** consists of a collection of views:there is a core view which we called canonical view,and also there are many different kinds of views around the core *** can transform the core view to the around view as we need.

关键词： EB-XML SMART theory inter-operation graph tree XSD WBS core data structure software development documents project schedule