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An Alternative Form of Inverse Scattering transform for the Korteweg-de Vries Equation

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Chinese Physics Letters 1998年第9期15卷 654-656页

作者： WU ke-xue CHEN Shi-rong Department of Physics Wuhan UniversityWuhan 430072

In the viewpoint of physics,for the Korteweg-de Vries(KdV)equation,we care the evolution effects of soliton with respect to space in perturbation theory,so the new boundary condition u→0 as t→∞is under our *** derive Zakharov-Shabat Equation of inverse scattering for the KdV equation under new condition starting from the second Lax *** the space dependences of scattering data are determined corresponding to time dependences of scattering data in traditional case,which are bases for developing perturbation theory under new condition.

关键词： equation. perturbation Equation

Introduction of a Reliable Method for Determination of Intrinsic Viscosity for Any Polymer with High Precision

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Chinese Journal of Polymer Science 2014年第2期32卷 209-217页

作者：熊晓鹏 Qi-rong ke Shi-qin Zhu Department of Materials Science and Engineering College of Materials Xiamen University Fujian Provincial key Laboratory of Polymer Materials Fujian Normal University Institut für Physikalische Chemie der Johannes Gutenberg-Universit t Mainz

Intrinsic viscosities for a given polyelectrolyte in salt free and low-salt solvents reported in literatures are normally not comparable, because of inadequate valuation procedures. this article describes a theoretically justified reliable method, which is free of any model assumptions： the so called Wolf plot （logarithm of the relative viscosity as a function of polymer concentration） enables the unequivocal determination of intrinsic viscosities for all kinds of macromolecules, irrespective of whether they are chain molecules of different architecture or globular polymers, whether they are charged or uncharged. the validation of the method was examined by evaluation of the viscosities of a polyelectrolyte, some uncharged polymers of different architectures, uncharged polymer blends, and some literature data.

关键词： Intrinsic viscosity Polyelectrolyte New method Wolf plot Introduction.

Representation of elliptic Ding-Iohara algebra

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Frontiers of Mathematics in China 2020年第1期15卷 155-166页

作者： Lifang WANG ke WU Jie YANG Zifeng YANG School of Mathematics and Statistics Henan universityKaifeng 475004China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

We define a vector representation V(u)of elliptic Ding-Iohara algebra u(q,t,p).Furthermore,we construct the tensor products of the vector representations and the Fock modulesF(u)by taking the inductive limit of certai... 详细信息

关键词： Elliptic Ding-Iohara algebra vector representation partition

Research of the terahertz dual-band notch filter based on FSS structures

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Chinese Science Bulletin 2013年第36期58卷 4687-4691页

作者： ZHANG JinLing ZHANG Yu GAO ke ZHAO GuoZhong School of Electronic Engineering Beijing University of Posts and Telecommunications School of Physics Capital Normal University

In this paper,a dual-band notch filter for two-layer frequency selective surface(FSS)at terahertz(tHz)frequency with high filtering performance has been realized on high-resistivity silicon *** periodic metallic resonators patterned on the silicon wafer,the designed filter can provide two tunable resonant frequencies for terahertz *** transmission response was improved by introducing an extra surrounding pattern around the t-shaped structure,and the location of transmission drop was tuned independently with geometric *** by finite-integral time-domain method,the filter is designed to operate between 0.2 and 0.6 tHz with dual-band band-stop performance,a salient feature of this design is making the low sensitivity of its frequency response to the incident angles,which allows to place the filter close to the radiation source with spherical wave *** proposed structures were fabricated using photolithography and tested by tHz time-domain spectroscopy *** results show that the transmission response has more than 12 and 32 dB rejections near 285 and 460 GHz respectively,which is in good agreement with the simulation result.

关键词：陷波滤波器太赫兹波 t形结构双频段 FSS 太赫兹时域光谱频率选择表面谐振频率

Friction stir welding of carbon nanotubes reinforced Al-Cu-Mg alloy composite plates

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Journal of Materials Science & technology 2017年第9期33卷 1004-1008页

作者： ke Zhao Zhenyu Liu Bolyu Xiao Zongyi Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Carbon nanotubes(CNts) reinforced Al-Cu-Mg composite plates of 2.2 mm in thickness after extrusion and t4 treatment were joined by friction stir welding(FSW) and the joint efficiency reaches 87%. there was no precipitate in both heat-affected zone(HAZ) and nugget zone(NZ) as a medium rotation rate of 800 rpm and a relative high travel speed of 100 mm min-1were used. In the NZ, FSW disarranged the alignment of CNts to random orientation and dispersed CNt uniformly. the orientation of CNts perpendicular to the tensile direction and the possible dissolution of solute clusters made the HAZ become the weakest zone in the joint leading to the failure in the HAZ.

关键词： Carbon nanotubes Metal matrix composites Friction stir welding

Discrete Capability of the Lempel-Ziv Complexity Algorithm on a Vibration Sequence

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Chinese Physics Letters 2010年第6期27卷 20-23页

作者： LI Jian-Kang SONG Xiang-Rong YIN ke Department of Engineering Mechanics Faculty of Science Jiangsu University Zhenjiang 212013 School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003

the Lempel Ziv complexity （LZC） method is used to analyze the acceleration response of the t-shaped plate. the response is converted into symbolic sequences with the multi-segmented coarse-grained method. the LZC of the response of 240 points located in different areas near the center is calculated. the results show that LZC arithmetic applied to elastomer vibration can satisfy the discreteness condition.

关键词： COMPUtAtIONAL complexity VIBRAtION (Mechanics) ALGORItHMS ACCELERAtION (Mechanics) ELAStOMERS PLAtES (Engineering)

Estimation of non-point source pollution loads with flux method in Danjiangkou Reservoir area,China

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Water Science and Engineering 2017年第2期10卷 134-142页

作者： Xiao-kang Xin Wei Yin ke-feng Li State key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Changjiang Water Resources Protection Institute Changjiang Water Resources Commission

the estimation of non-point source pollution loads into the Danjiangkou Reservoir is highly significant to environmental protection in the watershed. In order to overcome the drawbacks of traditional watershed numerical models, a base flow separation method was established coupled with a digital filtering method and a flux method. the digital filtering method has been used to separate the base flows of the Hanjiang,tianhe, Duhe, Danjiang, Laoguan, and Qihe rivers. Based on daily discharge, base flow, and pollutant concentration data, the flux method was used to calculate the point source pollution load and non-point source pollution load. the results show that:(1) In the year 2013, the total inflow of the six rivers mentioned above accounted for 95.9% of the total inflow to the Danjiangkou Reservoir. the total pollution loads of chemical oxygen demand(CODMn) and total phosphorus(tP) from the six rivers were 58.20 103 t and 1.863 10~3 t, respectively, and the non-point source pollution loads were 39.82 10~3 t and 1.544 10~3 t, respectively, indicating that the non-point source pollution is a major factor(with a contribution rate of 68.4% for CODMnand 82.9% for tP).(2) the Hanjiang River is the most significant contributor of pollution loads to the Danjiangkou Reservoir, and its CODMnand tP contribution rates reached 79.3% and 83.2%, respectively. the Duhe River took the second place.(3) Non-point source pollution mainly occurred in the wet season in 2013, accounting for 80.8% and 90.9% of the total pollution loads of CODMnand tP, respectively. It is concluded that the emphasis of pollution control should be placed on non-point source pollution.

关键词： Danjiangkou Reservoir Non-point source pollution Base flow separation Digital filtering method (DFM) Flux method

Repairing of exit-hole in friction-stir-spot welded joints for 2024-t4 aluminum alloy by resistance welding

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 660-669页

作者： Lipeng Deng Pengliang Niu Liming ke Jinhe Liu Jidong Kang School of Aeronautical Manufacturing and Engineering Nanchang Hangkong UniversityNanchang 330063China School of Material Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China Canmet MAtERIALS Natural Resources Canada183 Longwood Road SouthHamiltonON L8P0A5Canada

the exit-hole in friction stir spot welded(FSSWed) 2024-t4 aluminum alloy joints was successfully repaired by using a three-phase secondary rectification resistance spot welding machine, which is termed as filling exit-hole based on resistance welding(FEBRW). the filling dynamic behavior of force was recorded by a device monitoring. Optical microscope(OM), electron backscatter diffraction(EBSD), and tensile shear tests and finite element modelling were conducted to investigate the repairing stages and bonding mechanisms of the repaired joints in detail. Results showed that exit-hole was completely filled and repaired experiencing three stages. Metallurgical bonding was achieved between plug and exit-hole wall in two forms, including melting bonding in the middle of the joints and partial diffusion bonding on both the upper and bottom of the joints. the highest tensile shear strength of the repaired joints was 7.43 kN, which was 36.3% higher than that of the as welded joints. Resistance welding paves an efficient way to repair the exit-hole in FSSWed joints.

关键词： resistance welding exit-hole repairing bonding mechanisms

Research on manufacture technology of spherical fuel elements by dry-bag isostatic pressing

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Nuclear Science and techniques 2022年第10期33卷 79-89页

作者： Zhen-Ming Lu Wen-ke Zhang Jie Zhang Xiang-Wen Zhou Kai-Hong Zhang Ma-Lin Liu Xuan-ke Li Bing Liu Hubei Province key Laboratory of Coal Conversion and New Carbon Materials Wuhan University of Science and TechnologyWuhan 430081China Institute of Nuclear and New Energy technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyTsinghua UniversityBeijing 100084China

the steady development of high-temperature gas-cooled reactors(HtRs) has increased the requirements for the production cost and quality of fuel elements. Green fuel element pressing is one of the key steps to increase the production capacity. this paper proposes a proprietary vacuum dry-bag isostatic pressing(DIP) apparatus. the structural change of the matrix graphite powder during the DIP process was examined by analyzing the density change of the matrix graphite spheres with pressure. the soft molding process was simulated using the finite element method. the dimensional changes in the spheres during the pressing, carbonization, and purification stages were explored. the performance of the fuel matrix produced by the DIP method was comprehensively examined. the fuel matrix met the technical requirements and its anisotropy was significantly reduced. the DIP method can significantly improve both the production efficiency and quality of fuel elements. this will play a key role in meeting the huge demand for fuel elements of HtRs and molten salt reactors.

关键词： Dry-bag isostatic pressing High-temperature gas-cooled reactor(HtR) Spherical fuel element Finite element simulation Soft molding