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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 551-566页

作者： W.t.ANG X.wang School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Mechanical Engineering National University of SingaporeSingapore 117575Singapore

A boundary integral method with radial basis function approximation is proposed for numerically solving an important class of boundary value problems governed by a system of thermoelastostatic equations with variable coe?cients. the equations describe the thermoelastic behaviors of nonhomogeneous anisotropic materials with properties that vary smoothly from point to point in space. No restriction is imposed on the spatial variations of the thermoelastic coe?cients as long as all the requirements of the laws of physics are satis?ed. to check the validity and accuracy of the proposed numerical method, some speci?c test problems with known solutions are solved.

关键词： elliptic partial differential equation variable coefficient boundary element method radial basis function anisotropic thermoelastostatics

Locally Enhanced Flow and Electric Fields through a tip Effect for Efficient Flow‑Electrode Capacitive Deionization

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Nano-Micro Letters 2025年第2期17卷 1-17页

作者： Ziquan wang Xiangfeng Chen Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena titirici Libo Deng College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore Department of Engineering Faculty of Science and TechnologyBournemouth UniversityTalbot CampusFern BarrowPooleEngland BH125BBUK Institut de Chimie de Nice UniversitéCôte d’AzurUMR CNRS 727228 Av.Valrose06108 NiceFrance Department of Chemical Engineering Imperial College LondonSouth Kensington CampusExhibition RdLondon SW72AZUK

Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of ***,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current ***,a new tip-array current collector(designated as t-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport *** effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal *** the voltage increased from 1.0 to 1.5 and 2.0 V,the t-CC-based FCDI system(t-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current ***,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for t-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current ***,a salt removal efficiency of 99.89%was achieved with t-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.

关键词： Flow-electrode Capacitive deionization Current collector tip effect Desalination

thE tEMPERAtURE StRESS OF RC CONCREtE COMPONENt INDUCED BY LINEAR EXPENSION COEFFICIENt DIFFERENCE

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Journal of Wuhan University of technology(Materials Science) 1999年第1期14卷 58-61页

作者： wang, SR Mao, t Wuhan Univ technol Coll Architecture Dept Engn Wuhan 430070 Peoples R China

the temperature stress of reinforced concrete component caused by different linear expension coefficient has been discussed in this paper from the point of view of composite materials, the temperature dress can reach about 22 to 45 percent of the tension strength for the concrete with low grade and high ratio of reinforcement which should be considered seriously.

关键词： reinforced concrete linear expension coefficient stress

Peristaltic flow of Johnson-Segalman fluid in asymmetric channel with convective boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 697-716页

作者： h.YASMIN t.hAYAt A.ALSAEDI h.h.ALSULAMI Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of Science King Abdulaziz University

this work is concerned with the peristaltic transport of the Johnson-Segalman fluid in an asymmetric channel with convective boundary conditions. the mathematical modeling is based upon the conservation laws of mass, linear momentum, and energy. the resulting equations are solved after long wavelength and low Reynolds number are used. the results for the axial pressure gradient, velocity, and temperature profiles are obtained for small Weissenberg number. the expressions of the pressure gra-dient, velocity, and temperature are analyzed for various embedded parameters. Pumping and trapping phenomena are also explored.

关键词： asymmetric channel convective condition pumping and trapping Johnson-Segalman fluid

Polynaphthoxazines-Montmorillonite Nanocomposites: Synthesis and Characterization

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Chinese Chemical Letters 2001年第10期12卷 935-936页

作者： wang, CY Zhao, t Chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Polynaphthoxazines-clay nanocomposites were prepared from 1, 5-dihydroxynaphthalene, aniline, formaldehyde and different proportion montmorillonite(MMt) by in-situ reaction in ethanol. Dynamic tGA showed that nanocomposites have delayed decomposition temperatures when compared with pristine polynaphthoxazine indicating the enhancement in the thermal stability.

关键词： nanocomposites polynaphthoxazine montmorillonite

Separation and extraction of bridge dynamic strain data

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Frontiers of Structural and Civil Engineering 2009年第4期3卷 395-400页

作者： Baijian WU Zhaoxia LI Ying wang t.h.t.ChAN Department of Engineering Mechanics Southeast UniversityNanjing 210018China Department of Civil and Structural Engineering the Hong Kong Polytechnic UniversityHong KongChina

through comparing the measured data of dynamic strains due to loading and temperature by the stain gauge and temperature sensor at the same location,the information in the strain data was divided into three parts in the frequency domain by using the defined index named power spectral density(PSD)-ratio *** three parts are dominated respectively by temperature varying,stresses,and noises and thus can be distinguished from the determined the separatrix ***,a simple algorithm was developed to separate the three types of information and to extract the strain caused mainly by structural *** an application of the proposed method,the effect of strain deformation and noises on the fatigue assessment was investigated based on the separated *** results show that,the determined values of separatrix frequencies are valuable for the monitoring data from other *** algorithm is a multiresolution and hierarchical method,which has been validated as a simple and effective method for data analyses,and is suitable for the compression and preprocessing of the great amount monitoring data and easy to be integrated into the structural health monitoring(ShM)soft *** strain due to temperature varying attributes a little to the errors of fatigue assessment;however,the noises or random disturbance existed in the monitoring data have much responsibility for the errors,and the main reason is that the random disturbance shifts the real strain/stress amplitude picked up by real structural stress or strain.

关键词： structural health monitoring(ShM) structural strain information separation information extraction fatigue assessment

Formation of Re-containing Carbides in a Second Generation Directionally Solidified Ni Base Superalloy

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Journal of Materials Science & technology 2009年第3期25卷 361-364页

作者： t. Zhao D. wang J. Zhang G. Chen L.h. Lou School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

the precipitates at grain boundary in a directionally solidified Ni base superalloy after heat treatment, aging at 975℃, and creep rupture test have been characterized. Besides the primary MC carbides and fine particles of u phase, the Re-containing M23C6 was observed. the precipitation kinetics revealed that the formation of M23C6 was associated with the dissolution of u phase and MC carbides. tEM image shows that the continuous precipitation of M23C6 particles effectively hinders the dislocation movement and strengthens the grain boundaries. the high strength of the alloy suggests that M23C6 carbides are beneficial to the properties although Re as an important matrix strengthening element was consumed.

关键词： Ni-base Superalloys Directional solidification Rhenium Carbide

Achieving superior strength-ductility synergy in a heterostructured magnesium alloy via low-temperature extrusion and low-temperature annealing

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Journal of Materials Science & technology 2023年第32期163卷 32-44页

作者： h.wang D.t.Zhang C.Qiu W.W.Zhang D.L.Chen Guangdong Key Laboratory for Advanced Metallic Materials Processing and Forming National Engineering Research Center of Near-net-shape Forming for Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China Department of Mechanical and Industrial Engineering Toronto Metropolitan University(formerly Ryerson University)350 Victoria StreetTorontoON M5B 2K3Canada

A low-alloyed Mg-1.2Zn-0.1Ca(wt.%)alloy was fabricated via low-temperature extrusion and annealing at 250℃for different times(10,30,and 90 min)to attain heterostructures with different fine-grained fractions,focusing on the effect of heterostructure on the mechanical *** dynamic recrystallization(RX)occurred during extrusion at 150℃,and a lamellar structure consisting of fine RX grains and coarse unRX grains was *** subsequent annealing promoted static RX in the as-extruded alloy,leading to an increased fine-grained fraction from 67%to 95%.Meanwhile,the co-segregation of Zn and Ca atoms impeded the migration of grain boundaries,thus achieving a fine grain size of 0.8–1.6μ*** sample annealed for 10 min with a fine-grained fraction of 73%and an average RX grain size of 0.9μm exhibited a superior combination of high yield strength(305 MPa)and good ductility(20%).In comparison,an excellent elongation of 30%was achieved in the alloy with a nearly fully-RXed microstructure and an average grain size of 1.6μm after 90 min annealing,despite a lower yield strength of 228 *** unRX grains,the hard orientation with(01–10)parallel to the extrusion direction and high-density dislocations made it more difficult to deform compared with the RX grains,thus producing hetero-deformation induced(hDI)*** fine grains and high-density dislocations,hDI strengthening is the key to achieving the superior mechanical properties of the low-alloyed Mg alloy.

关键词： Low-alloyed magnesium alloy Low-temperature extrusion Annealing heterostructure Mechanical properties

Experimental study of channel delay impact on throughput performance of tCP and its extensions in space

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第10期6卷 1015-1020页

作者： wang Ru-fa wang Ru h. School of Computer Science Gansu Institute of Political Science and Law Lanzhou 730070 China Department of Electrical Engineering. Lamar University Beaumont TX 77710-1829 USA

Substantially long round trip time (Rtt) in space channel hurts tCP interactions between the sending and receiving ends, and limits the usefulness and effectiveness of tCP feedback. Space Communication Protocol Standards-transport Protocol (SCPS-tP) is a transmission Control Protocol (tCP) enhancement method aimed at improving its performance in space and interplanetary Internet and is expected to have capability of being feasible applied to experimental evaluation of the effectiveness of SCPS-tP in coping with long channel delay. this paper presents an experimental evaluation of channel delay impact on throughput performance of SCPS-tP over LEO/GEO-stationary space links using a test-bed, compared with the widely deployed tCP.

关键词： Intemet protocols Satellite communication Channel delay tCP SCPS-tP

Numerical simulation of triaxial compression test for brittle rock sample using a modified constitutive law considering degradation and dilation behavior

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Journal of Central South University 2015年第8期22卷 3097-3107页

作者：谭鑫 KONIEtZKY h FRühWIRt t College of Civil Engineering Hunan University Geotechnical Institute TU Bergakademie Freiberg

the understanding of the rock deformation and failure process and the development of appropriate constitutive models are the basis for solving problems in rock engineering. In order to investigate progressive failure behavior in brittle rocks, a modified constitutive model was developed which follows the principles of the continuum damage mechanics method. It incorporates non-linear hoek-Brown failure criterion, confining pressure-dependent strength degradation and volume dilation laws, and is able to represent the nonlinear degradation and dilation behaviors of brittle rocks in the post-failure region. A series of triaxial compression tests were carried out on Eibenstock(Germany) granite samples. Based on a lab data fitting procedure, a consistent parameter set for the modified constitutive model was deduced and implemented into the numerical code FLAC3 D. the good agreement between numerical and laboratory results indicates that the modified constitutive law is well suited to represent the nonlinear mechanical behavior of brittle rock especially in the post-failure region.

关键词： progress failure strength degradation dilation hoek-Brown criterion numerical simulation brittle rock