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Infinite Conservation Laws for Nonlinear Integrable Couplings of Toda Hierarchy

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Chinese Physics Letters 2012年第9期29卷 1-4页

作者： YU fa-Jun School of mathematics and Systematic Sciences Shenyang Normal UniversityShenyang 110034

We construct nonlinear integrable couplings of discrete soliton hierarchy,then the infinite conservation laws for the nonlinear integrable couplings of the lattice hierarchy are *** explicit application of the method proposed,the infinite conservation laws of nonlinear integrable couplings of the Toda lattice hierarchy are *** obtained integrable couplings of the Toda lattice equations and conservation laws can be used to describe the possible formation mechanisms for hydrodynamics,solid state physics and plasma physics,respectively.

关键词： integrable nonlinear lattice

On the Variation of a metric and Its Application

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Acta mathematica Sinica,English Series 2010年第10期26卷 2003-2014页

作者： fa En WU Department of mathematics School of Science Beijing Jiaotong University Beijing 100044 P. R. China

Some of the variation formulas of a metric were derived in the literatures by using the local coordinates system, In this paper, We give the first and the second variation formulas of the Riemannian curvature tensor, Ricci curvature tensor and scalar curvature of a metric by using the moving frame method. We establish a relation between the variation of the volume of a metric and that of a submanifold. We find that the latter is a consequence of the former. Finally we give an application of these formulas to the variations of heat invariants. We prove that a conformally flat metric g is a critical point of the third heat invariant functional for a compact 4-dimensional manifold m, then （m, g） is either scalar flat or a space form.

关键词： Riemannian functional variation of a metric volume variation space form heat invariant

Ferrofluid magnetoviscous control of wall flow channeling in porous media

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China Particuology 2007年第1期5卷 50-60页

作者： faal Larachi Damien Desvigne Department of Chemical Engineering Laval University Que. G1K 7P4 Canada

We analyzed the phenomenon of ferrofiuid magnetoviscosity in high-permeability wall-region non-magnetic porous media of the müller kind. After upscaling the pore-level ferrohydrodynamic model, we obtained a simplified volume-average zero-order axisymmetric model for non-Darcy non-turbulent flow of steady-state isothermal incompressible Newtonian ferrofluids through a porous medium experiencing external constant bulk-flow oriented gradient magnetic field, ferrofluid self-consistent demagnetizing field and induced magnetic field in the solid. The model was explored in contexts plagued by wall flow maldistribution due to low column-to-particle diameter ratios. It was shown that for proper magnetic field arrangement, wall channeling can be reduced by inflating wall flow resistance through magnetovisco-thickening and Kelvin body force density which reroute a fraction of wall flow towards bed core. 　　

关键词： Ferrofluid magnetosviscosity Porous medium Volume-average ferrohydrodynamic model Kelvin body force Spin-vorticity coupling

Embedding Derivatives and Integration Operators on Hardy Type Tent Spaces

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Acta mathematica Sinica,English Series 2022年第6期38卷 1069-1093页

作者： mao fa WANG Lv ZHOU School of mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we completely characterize the positive Borel measuresμon the unit ball B_(n)such that the differential type operator R^(m)of order m∈N is bounded from Hardy type tent space HT_(q,α)^(p)(B_(n))into L^(s)(μ)for full range of p,q,s,α.Subsequently,the corresponding compact description of differential type operator R^(m)is also *** an application,we obtain the boundedness and compactness of integration operator J_(g)from HT_(q,α)^(p)(B_(n))toHT_(s,β)^(t)(B_(n)),and the methods used here are adaptable to the Hardy spaces.

关键词： Embedding derivative integration operator Hardy type tent space Carleson measure

The consensus on liver autotransplantation from an international panel of experts

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Hepatobiliary & Pancreatic Diseases International 2017年第1期16卷 10-16页

作者： Qi-fa Ye Norbert Senninger Zhongnan Hospital of Wuhan University Institute of Hepatobiliary Diseases of Wuhan University Transplant Center of Wuhan University Hubei Key Laboratory of Medical Technology on Transplantation Research Center of National Health ministry on Transplantation medicine Engineering and Technology The 3rd Xiangya Hospital of Central South University Department of General Surgery University Clinics of Münster

Introductionmore than 1.0 million patients worldwide are diagnosed with space-occupying lesions in the liver every year, with the number approaching 0.5 million per year in China, and only 20% of the lesions are resectable Due to a lack of available donors, only a limited number of patients underwent allogeneic liver transplantation, the remaining patients simply receive palliative care. Therefore, discovering new options for treating these patients is a high priority. Liver autotransplantation （LAT） is a surgical technique that adopts liver transplantation skills to radically treat spaceoccupying hepatic lesions, benign or malignant,

关键词： The consensus on liver autotransplantation from an international panel of experts

High—Efficiency Organic Double—Quantum—Well Light—Emitting Devices Using 5,6,11,12—Tetraphenylnaphthacene Sub—monolayer as Potential Well

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Chinese Physics Letters 2003年第6期20卷 956-958页

作者： XIEWen-fa LIChuan-Nan LIUShi-Yong NationalLaboratoryofIntegratedOptoelectronics JilinUniversityChangchun130023

The double-quantum-well organic light-emitting devices of indium-tin-oxide (ITO)/NPB (50 nm)/rubrene (0.05 nm)/ NPB(4 nm)/rubrene (0.05 nm)/Alq3 (50 nm)/LiF (0.5 nm)/Al were fabricated, in which N,N-bis-(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine (NPB) is used as a barrier potential or hole transport layer, tris (8-hydroxyquinoline) aluminium (Alq3) used as electron transport layer, and 5,6,11,12-tetraphenylnaphthacene (rubrene) as a potential well and emitter. The brightness can reach 18610 cd/m2 at 13 V. The maximum electroluminescent efficiency of the device was 6.61 cd/A at 7 V, which was higher than that of common dope-type devices. In addition, the electroluminescence efficiency is relatively independent of the drive voltage in the range from 5 to 13 V.

关键词： Tin oxides

SYSTHESIS OF DOUBLE-HYDROPHILIC CORE-SHELL TYPE mULTIARm STAR COPOLYmER POLYETHYLENImINE-block-POLY(2-HYDROXYETHYL mETHACRYLATE)

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Chinese Journal of Polymer Science 2013年第7期31卷 1046-1055页

作者： Qiang Tang fa Cheng Jin Cui 陈宇 School of Chemical and Environmental Engineering Hubei University of Technology Department of Chemistry School of SciencesTianjin University National Foodstuff Inspection Center Tianjin Product Quality Inspection Technology Research Institute

multiarm star block copolymers hyperbranched polyethylenimine-b-poly（2-hydroxyethyl methacrylate）（HPEI-b- PHEmA） with average 28 PHEmA arms have been prepared by atom transfer radical polymerization （ATRP） of HEmA in a mixed solvent of methanol and water using a core-first strategy. The hyperbranched macroinitiator employed was prepared on the basis of well-defined hyperbranched polyethylenimine with mw/mn of 1.04 by amidation with 2-bromo-isobutyryl bromide. The polymerization condition was optimized to prepare star copolymers with narrow dispersity, and the variables included the volume ratio of methanol to water, the molar ratio of initiating site to CuC1 and the molar ratio of [CuCl]：[CuBr2]. Under the optimized polymerization condition, the lowest mw/mn value of the obtained star copolymers was around 1.3. Kinetic analysis showed that an induction period existed in the polymerization of HEmA. After this induction period, a linear dependence of ln（[m]0/[m]t） on time was observed. The obtained HPEI-b-PHEmA could adsorb hydrophilic molecules. The comparison with the star copolymer with hydrophobic core and hydrophilic PHEmA shell verified that both the hydrophilic core and shell could host the hydrophilic guests, but the amidated HPEI core was more effective than the PHEmA shell.

关键词： Atom transfer radical polymerization Hyperbranched Polyethylenimine Poly(2-hydroxyethyl methacrylate) Star polymers.

The modeling analysis of microwave emission from stratified media of non-uniform lunar cratered terrain surface for Chinese Chang-E1 observation

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Chinese Science Bulletin 2011年第11期56卷 1165-1171页

作者： JIN YaQiu fa WenZhe Key Laboratory of Wave Scattering and Remote Sensing Information (mOE) Fudan University Shanghai 200433 China

In China's first lunar exploration project,Chang-E 1,the multi-channel (3.0,7.8,19.35,37 GHz) microwave radiometers were aboard the satellite,with the purpose of measuring microwave brightness temperature from lunar surface and surveying the global distribution of lunar regolith layer thickness,and global evaluation of 3He *** analyze the modeling of microwave radiative transfer from three-layered media of lunar surface,some factors,such as the cratered lunar surface roughness,scattering of regolith particulate medium with temperature profile,are *** on the statistics of the lunar cratered terrain and using monte Carlo (mC) method,the cratered lunar surfaces are numerically *** triangulated network is utilized to divide the undulated lunar surface into discrete triangle meshes with the size 10 m as a digital surface *** reflectivities of each plane mesh are calculated,and the average reflectivity for all mC-realized lunar surfaces is *** is found that under the spatial resolution of 30 km×30 km of Chang-E 1 radiometer observation,the lunar surface can be well modeled as a flat *** makes the predominance of the parameters,such as the regolith layer thickness and stratified structures,to be *** the radiative transfer equation of stratified media with dense scatterers,the scattering coefficient of the regolith particulate medium is found negligible,and the emission is mainly governed by the absorptive property of the *** temperature of multi-layered media,*** soil,regolith layer with temperature profile and underlying rock media,are derived and calculated,and relevant main factors to affect the modeling and emission simulation are analyzed.

关键词：月球探测工程微波发射分层介质地形表面陨石坑模型分析中国非均匀

A Finite Element Based Study on Lowering Operation of Subsea massive Structure

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China Ocean Engineering 2017年第5期31卷 646-652页

作者： WANG fa-cheng WANG Jun TANG Ke Department of Civil Engineering Tsinghua University COTEC Offshore Engineering Solutions

Subsea production system has been increasingly used in recent South China Sea offshore developments. With deepwater applications, constituent parts of subsea systems become more complicated and enlarged. Increases on the weight and geometry of each component bring challenges to installations. A recent accomplished deployment on a subsea massive jumper shows the weight and length have been up to 120 tons and 90 m, respectively with sophi- sticated geometry. It is considerably difficult to install heavy and large subsea structures, especially in South China Sea where severe environmental conditions are common. In addition, deepwater deployment may alter natural frequency of the hoisting system and the altered frequency may be close to possible environmental conditions. To deal with the above two issues, traditionally, engineers need to carry out series of complicated numerical analyses which are on case basis and significantly time-consuming. Existing studies focus on the optimization on analysis techniques by conducting laboratory testing and numerical simulations. However, easy-to-use guidance on massive subsea structure installation are somewhat limited. The studies presented in this paper aim to achieve a simplified guidance which can briefly screen the cases subject to axial resonance and provide visible correlations between hoisting system integrity and key installation parameters.

关键词： subsea massive saucture sensitivity analysis DAF