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Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science china Earth {1. 2006年第6期49卷 650-660页

作者： huang Hai{1.1.& GUO Boling2.1. Department of mathematics, beijing Normal University, beijing 1.0875, china 2. institute of applied Physics and Computational mathematics,{12., china 1. Department of mathematics Beijing Normal University Beijing 100875 China 2. institute of {1. Physics and Computational {2. Beijing 100080 China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Kumada chain-growth polycondensation as a universal method for synthesis of well-defined conjugated polymers

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Science china Chemistry 2010年第8期53卷 1620-1633页

作者： GENG YanHou1.huang Li1.2.WU ShuPeng1.2.& WANG FoSong1.1.tate Key Laboratory of Polymer Physics and Chemistry Changchun {1. of applied Chemistry,chinese Academy of sciences,Changchun 1.002.,china 2.raduate University of chinese Academy of sciences,beijing 1.0049,china 1. State Key Laboratory of Polymer Physics and Chemistry Changchun institute of {1. Chemistry Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Kumada chain-growth polycondensation (KCGP) is a novel method for the synthesis of well-defined conjugated *** the Ni-catalyst can transfer in an intramolecular process to the propagating chain end,the polymerization follows chain-growth *** this newly developed method,various conjugated polymers,such as polythiophenes,poly(p-phenylene) (PPP),polypyrrole (PPy),and polyfluorene with controlled molecular weights and relatively narrow polydispersities (PDIs),have been ***,the polymerizations for poly(3-alkylthiophene)s (P3ATs),PPP,and PPy exhibited quasi-living characteristics,which allows preparing polymer brushes,fully-conjugated block copolymers,and macroinitiators and macro-reactants for the synthesis of rod-coil block *** the current review,the progress in this new area is summarized.

关键词： chain growth polycondensation conjugated polymers Kumada reaction block copolymers polymer brush

Inverse design of nonlinear phononic crystal configurations based on multi-label classification learning neural networks

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chinese Physics B 2024年第10期33卷 295-301页

作者： Kunqi huang Yiran Lin Yun Lai {1. Liu Key Laboratory of Modern Acoustics Institute of AcousticsNanjing UniversityNanjing 210093China School of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Phononic crystals,as artificial composite materials,have sparked significant interest due to their novel characteristics that emerge upon the introduction of *** these properties,second-harmonic features exhibit potential applications in acoustic frequency conversion,non-reciprocal wave propagation,and non-destructive *** manipulating the harmonic band structure presents a major challenge in the design of nonlinear phononic *** design approaches based on parameter adjustments to meet specific application requirements are inefficient and often yield suboptimal ***,this paper develops a design methodology using Softmax logistic regression and multi-label classification learning to inversely design the material distribution of nonlinear phononic crystals by exploiting information from harmonic transmission *** results demonstrate that the neural network-based inverse design method can effectively tailor nonlinear phononic crystals with desired *** work establishes a mapping relationship between the band structure and the material distribution within phononic crystals,providing valuable insights into the inverse design of metamaterials.

关键词： multi-label classification learning nonlinear phononic crystals inverse design

Economical cascadic multigrid method (ECMG)

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Science china {1. 2007年第12期50卷 1765-1780页

作者： Zhong-ci SHI~1 Xue-jun XU~(1+) Yun-qing huang~2.~1 LSEC,institute of Computational {2.,Academy of {2. and Systems Science,chinese Academy of sciences,beijing 100080,china ~2.Hunan Key Laboratory for Computation and Simulation in Science and Engineering,institute for Computational and applied {2.,Xiangtan University,Xiangtan 411105,china LSEC Institute of Computational Mathematics Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China Hunan Key Laboratory for Computation Simulation in Science Engineering Institute for Computational applied {1. Xiangtan University Xiangtan 411105 China

In this paper, an economical cascadic multigrid method is proposed. Compared with the usual cascadic multigrid method developed by Bornemann and Deuflhard, the new one requires less iterations on each level, especially on the coarser grids. Many operations can be saved in the new cascadic multigrid algorithms. The main ingredient is the control of the iteration numbers on the each level to preserve the accuracy without over iterations. The theoretical justification is based on the observations that the error reduction rate of an iteration scheme in terms of the smoothing property is no longer accurate while the iteration number is big enough. A new formulae of the error reduction rate is employed in our new algorithm. Numerical experiments are reported to support our theory.

关键词： economical cascadic multigrid method (ECMG), cascadic multigrid method (CMG)

Experimental investigation of supersonic radiation propagation in low-density plastic and copper-doped foams

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Science china(Physics,Mechanics & Astronomy) 2005年第5期48卷 549-558页

作者： JIANG Shaoen1. XU Yan2. DING Yongkun1. LAI Dongxian2. ZHENG Zhijian1. huang Yixiang1. LI Jinghong2. SUN Kexu1. HU Xin1. ZHANG Wenhai1. YI Rongqing1. CUI Yanli1.& CHEN Jiusen1.1. National Key Laboratory of Laser Fusion, Laser Fusion Research Center, Mian{1. 62.0}00, china 2. institute of applied Physics and Computation mathematics, beijing, 1.0088, china 1. National Key Laboratory of Laser Fusion Laser Fusion Research Center 621900 Mianyang China 2. institute of {1. Physics and Computation {2. 100088 Beijing China

Eight beams of 0.35 μm laser with pulse duration of 1.ns and total energy of 2.kJ enter into a hohlraum to create intense X-ray radiation of 1.0 eV on the Shenguang ΙΙ laser facility. Plastic foam (C6H1.) and copper-doped foam (C6H1.Cu0.394) with a density of 50 mg/cm3 are heated by X-ray radiation emitted from the hohlraum. The breakout time of the radiation wave is measured by a tri-chromatic streaked X-ray spectrometer (TCS) that consists of a set of three imaging pinholes and an array of three transmission gratings coupled with an X-ray streak camera (XSC). At one shot, the simultaneous measurements of the delay of the drive source and the radiation transport at two energies (2.0} eV, 840 eV) through the foam have been made for the first time. The experimental results indicate that the time delays vary with photon energies. With a transmission grating spectrometer (TGS), the spectra transmitting foams were measured, and the lower limit of the optical depth was measured. The radiation at energy of 2.0} eV propagates through plastic foam at a faster velocity, compared with the radiation at energy of 840 eV; while the results of copper-doped foam are reverse. The optical depth in the plastic foam is less than 1. and in the doped foam it is more than 1.

关键词： supersonic radiation wave, plastic foam, copper-doped foam, optical depth.

Interface and properties of epoxy resin modified by elastomeric nano-particles

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Science china Chemistry 2005年第2期48卷 148-155页

作者： huang Fan1. LIU Yiqun1. ZHANG Xiaohong1. GAO Jianming1. SONG Zhihai1. TANG Banghui1. WEI Genshuan2.& QIAO Jinliang1.1. SINOPEC {1. Research institute of Chemical Industry, {1. 1.001., china 2. institute of applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, beijing 100080, china Correspondence should be addressed to Qiao Jinliang (email: jqiao@***.) 1. SINOPEC beijing Research {1. of Chemical Industry 100013 Beijing China 2. institute of {1. Chemistry College of Chemistry and Molecular Engineering Peking University 100080 Beijing China

Study on a new composite of epoxy resin/elastomeric nano-particles (ENP) is re- ported in this paper, which shows that, in comparison with pure epoxy resin and epoxy toughened with CTBN, the composites of epoxy resin/carboxylic nitrile-butadiene ENP and epoxy resin/styrene butadiene vinyl-pyridine ENP possess both higher toughness and heat resistance. Both ENPs used in the study have an average size of less than 1.0 nm. Study on the epoxy network’s morphology and interface properties suggests that due to the chemical reaction be- tween ENP and epoxy resin and more hydrogen bonds between nitrile groups of the rubber and hydroxyl groups of the epoxy resin, stronger interaction at the larger interface may lead to the observed excellent properties of the epoxy resin toughened with ENP.

关键词： elastomeric nano-particles, epoxy resin, carboxylic nitrile-butadiene rubber, styrene butadiene vinyl-pyridine rubber, interface.

The asymptotic stability of multistep multiderivative methods for systems of delay differential equations

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Communications in Nonlinear Science and Numerical Simulation 2000年第1期5卷 24-26页

作者： Chengming huang and Qianshun CHANG {1. of {2. mathematics, chinese Academy of sciences, P. O. Box 2.34, beijing 100080, china institute of {1. {2. Chinese Academy of Sciences P. O. Box 2734 Beijing 100080 China

This paper deals with the asymptotic stability of multistep multiderivative methods for systems of delay differential equations. In particular, it is shown that A-stability of multistep multiderivative methods for ord... 详细信息

关键词： delay differential equation stability multistep multiderivative methods

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： huang YongChang1,3,4, JIANG YunGuo1 & LI XinGuo2.3 1 institute of Theoretical Physics, College of {2. sciences, beijing University of Technology, beijing 10002., china 2.institute of Modern Physics, chinese Academy of sciences, Lanzhou 730000, china 3 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Collisions, chinese Academy of sciences, Lanzhou 730000, china 4 china Center of Advanced Science and Technology (World Laboratory), beijing 100080, china 1. institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing 100022 China 3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou 730000 China 4. china Center of Advanced Science and Technology (World Laboratory) Beijing 100080 China 2. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Greenhouse Gas Emissions from Northeast china Rice Fields in Fallow Season

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Pedosphere 2007年第5期17卷 630-638页

作者： LIANG Wei SHI Yi ZHANG Hua YUE Jin huang Guo-Hong institute of {1. Ecology Chinese Academy of Sciences Shenyang 110016 （China） Graduate School of the chinese Academy of {1. Beijing 10005g （China） College of Resources and Environment Huazhong Agricultural University Wuhan 430070 （China）

CH4, N2. and CO2.emissions from northeast chinese rice fields were measured in the fallow season （November to March） to investigate the effects of freezing-thawing on the emissions. Both CH4 emission from and atmospheric CH4 oxidation by the soil occurred, but the flux was small. During the fallow season, rice fields acted as a minor source of atmospheric CH4, which accounted for about 1. of the CH4 emission during the rice growing period. The field was also a substantial source of atmospheric N2., which ranged between 40 to 77 mg m-{1. eu=counted for 40%-50% of the annual N2. emission. The largest N2. flux was observed in the thawing period during the fallow season. Laboratory incubation tests showed that the largest N2. flux came from the release of N2. trapped in frozen soil. Tillage and rice straw application （either mulched on the soil surface or incorporated in the soil） stimulated the CH4 and CO2.emissions during the fallow season, but only straw application stimulated N2. emission substantially.

关键词： CH4 CO2 freezing-thawing N2. rice field