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The roles of polymer-graphene interface and contact resistance among nanosheets in the effective conductivity of nanocomposites

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1941-1956页

作者： y.ZARE K.y.RHEE Department of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 17104Republic of Korea

The effective conductivity of graphene-based nanocomposites is suggested by the characteristics of polymer-filler interfacial areas as well as the contact resistance between the neighboring *** interfacial properties are expressed by the effective levels of the inverse aspect ratio and the filler volume ***,the resistances of components in the contact regions are used to define the contact resistance,which inversely affects the effective *** obtained model is utilized to predict the effective conductivity for some *** discrepancy of the effective conductivity at various ranks of all factors is *** interfacial conductivity directly controls the effective conductivity,while the filler conductivity plays a dissimilar role in the effective conductivity,due to the incomplete interfacial adhesion.A high operative conductivity is also achieved by small contact distances and high interfacial ***,big contact diameters and little tunnel resistivity decrease the contact resistance,thus enhancing the effective conductivity.

关键词： polymer nanocomposite operative conductivity graphene interfacial property contact region

Effect of Titanium,Antimony,Cerium and Carbon Nanotubes on the Morphology.and Microhardness of Mg-based Icosahedral Quasicrystal Phase

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Journal of Materials Science & Technology 2010年第1期26卷 27-32页

作者： Zhifeng Wang, weimin Zhao, Haipeng Li, Jian Ding, yongyan Li and Chunyong Liang School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China [a] School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China

For the first time, petal-like and spherical Mg-based icosahedral quasicrystal phase （I-phase） were obtained by introducing Ti, Sb, Ce and C nanotubes into Mg-Zn-y alloy under normal casting conditions. The formation mechanism and stability criterion of spherical I-phase were discussed. The morphology.and microhardness of I-phase and their determinants were studied in this paper. The results show that the different value of microhardness of I-phase could be attributed to the different kinds of the fourth component and its content, and its different innate characters. The final morphology of icosahedral quasicrystalline （IQC） is decided by the size of critical stable radius Rr, the content of the fourth component and degree of undercooling.

关键词： Quasicrystal Magnesium alloy Morphology Microhardness

y-Ba-Cu-O mixed oxides for production of diphenols in liquid-solid phase

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Chinese Journal of Chemistry 1996年第6期14卷 516-524页

作者： Liu, CB Zhao, Z yang, XG ye, XK Wu, y CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022JILINPEOPLES R CHINA

Superconductor mixed oxides were often used as catalysts at higher temperature in gas phase oxidations, and considered not suitable for lower temperature reactions in the liquid-solid phase; here the catalysis of yBa2Cu3O7+/-x and y2BaCuO5+/-x in the phenol hydroxylation at lower temperature with H2O2 as oxygen donor was studied, and found that the superconductor yBa2Cu3O7+/-x, has no catalytic activity for phenol hydroxylation, but y2BaCuO5+/-x does, even has better catalytic activity.and stability than most previously reported ones. With the studies of catalysis of other simple metal oxides and perovskite-like mixed oxides, a radical substitution mechanism is proposed and the experimental facts are explained clearly, and draw a conclusion that the perovskite-like mixed oxides with (AO)(ABO(3)) and (AO)2(ABO(3)) structure have better catalytic activity than the simple perovskite oxides with (ABO(3))(3) structure alone, and (AO) structure unit is the key for the mixed oxides to have the phenol hydroxylation activity. No pollution of this process is very important for its further industrial application.

关键词： superconductor mixed oxides phenol hydroxylation radical substitution

Effect of y Addition on Microstructure and Mechanical Properties of Friction Stir Welded ZK60 Alloy

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Journal of Materials Science & Technology 2009年第3期25卷 351-355页

作者： G.M. Xie Z.y. Ma L. Geng School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

6 mm thick ZK60 and ZK60-y alloy plates were successfully friction stir welded （FSW） at a tool rotation rate of 1200 r/min and a traverse speed of 100 mm/min. FSW resulted in the dissolution of MgZn2 particles in the ZK60 and the breakup and dispersion of W-phase （Mg3Zn3y2） particles in the ZK60-y alloy, thereby leading; to a decrease in the hardness of the nugget zone （NZ） for the ZK60 alloy.and an increase in the hardness of the NZ for the ZK60-y alloy, respectively. While two FSW joints exhibited similar joint efficiency （87%-89% of ultimate tensile strengths of the parent materials）, the yield strength of the FSW ZK60-y joint was substantially higher than that of the FSW ZK60 joint. The fracture occurred in the NZ and the heat affected zone for the ZK60 and ZK60-y joints, respectively, which were consistent with the lowest hardness distribution of the welded joints.

关键词： Friction stir welding Magnesium Microstructure Mechanical properties

Numerical Simulation of Electroosmotic Flow near Earthworm Surface

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Journal of Bionic Engineering 2006年第4期3卷 179-186页

作者： y.Q. Zu y.y. yan School of the Built Environment The University of Nottingham Nottingham NG7 2RD UK

The electroosmotic flow near an earthworm surface is simulated numerically to further understand the anti soil adhesion mechanism of earthworm. A lattice Poisson method is employed to solve electric potential and charge .distributiorts in the electric double layer along the earthworm surface. The external electric field is obtained by solving a Laplace equation. The electroosmotic flow controlled by the Navier-Stokes equations with external body force is simulated by the lattice Boltzmann method. A benchmark test shows that accurate electric potential distributions can be obtained by the LPM. The simulation shows that the moving vortices, which probably contribute to anti soil adhesion, are formed near earthworm body surface by the nonuniform and variational electrical force.

关键词： electroosmotic flow earthworm anti-adhesion LBM EDL

A hyperbolic Lindstedt-Poincare method for homoclinic motion of a kind of strongly nonlinear autonomous oscillators

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Acta Mechanica Sinica 2009年第5期25卷 721-729页

作者： y.y.Chen S.H.Chen K.y.Sze Department of Applied Mechanics and Engineering Sun yat-sen University Department of Mechanical Engineering The University of Hong Kong Department of Applied Mechanics and Engineering Sun Yat-sen University

A hyperbolic Lindstedt-Poincare method is presented to determine the homoclinic solutions of a kind of nonlinear oscillators, in which critical value of the homoclinic bifurcation parameter can be determined. The generalized Lienard oscillator is studied in detail, and the present method＇s predictions are compared with those of Runge-Kutta method to illustrate its accuracy.

关键词： Lindstedt-Poincare method Hyperbolic function Nonlinear autonomous oscillator - Homoclinic orbit

Microstructure of Laser Remelted Ni-base Alloy Coating on Stainless Steel

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Journal of Materials Science & Technology 1998年第1期14卷 49-52页

作者： Gao, y Liang, y Shi, CX Inst Aeronaut Mat Beijing 100095 Peoples R China Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

A 5 kW CW CO2 gas laser was used to produce NiCrBSi superalloy coatings. Powders were preplaced by plasma-spraying. The microstructure and chemical composition of the coating have been studied by SEM, XRD and HREM. The results show the coating microstructure is fine dendrites, composed of gamma matrix, gamma' and boride (NiB) eutectic, the lattice parameter of the gamma matrix is 0.3572 nm and there is a metallurgical bonding in interface.

关键词： Stainless steel

MTCA.4-based LLRF control system for the C-ADS proton Linac injector I

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Radiation Detection Technology.and Methods 2017年第1期1卷 13-20页

作者： R.Liu X.P.Ma N.Gan H.y.Lin Q.y.Wang Z.H.Mi S.Z.Wang X.F.Huang yan Wu G.W.Wang y.L.Chi weimin Pan Key Laboratory of Particle Acceleration Physics and Technology IHEPCASBeijing 100049China

Objective:The Chinese ADS proton Linac injector I composed of an electron cyclotron resonance ion source,a lowenergy beam transport line,a radio frequency quadrupole(RFQ)accelerator,a medium-energy beam transport(MEBT)line,a superconducting section and beam dump with design goal to achieve CW proton beam with beam current 10 mA and energy gain around 10 *** order to maintain the stability of the RF system,to compensate for the beam load effect and to provide the GUI required for the operation of the RF power system,we have established a LLRF control ***:This LLRF system for ADS proton Linac injector I in IHEP consists of RF reference system and LLRF controllers for oneRFQcavity,twoMEBTbunching cavities and 14 superconductive spoke *** have adopted a new development mTCA.4-based hardware platform,and it has some characteristics such as faster bandwidth,standardized design,easy operation and maintenance and good ***:The LLRF system has been improved and optimized and has now been put into *** takes into account the pulse and CW beam flow mode,feedforward and feedback control ***:With the help of this system,we achieved stable operationwith narrowpulses,long pulses,andCWmodes under different beam *** article describes the implementation of this system and presents some initial the CW beam acceleration results with the help of this system at the end of 2016.

关键词： RF system RFQ Spoke cavity LLRF MTCA.4 CW proton beam

Modification of the Micro Arc-oxidized Ti Surface for Implant Applications

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Journal of Bionic Engineering 2021年第6期18卷 1391-1399页

作者： Eren yılmaz Department of Welding Technology Sakarya Applied Sciences UniversityArifi ye Vocational High School54187SakaryaTurkey Sakarya Applied Sciences University Materials Research Center(SUMAR) 54187SakaryaTurkey

Surface treatments applied to titanium and its alloys for implant applications are important for the development of bio *** this study,first an oxide layer was formed on the surface of the titanium plate by micro arc oxidation,and then both calcium phosphate and calcium phosphate/chitosan accumulation were performed for different samples by the sol-gel ***-SEM/EDS examinations,XRD,FTIR and thermal analysis were performed for these micro arc-oxidized,calcium phosphate-coated and calcium phosphate/chitosan-coated *** surface roughnesses for these surfaces were measured between 10μm and 100μm,suitable for bone development on the *** effect of chitosan addition on the calcium phosphate-coated surface on apatite formation ability.and antibacterial properties was *** the addition of chitosan slows down the formation of apatite,it ensured that the coating had antibacterial *** calcium phosphate/chitosan biocomposite obtained can be recommended for dental and orthopedic implants.

关键词： Micro arc oxidation Sol-gel Hydroxyapatite Chitosan Implant