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Acta Mechanica Sinica 2018年第3期34卷 507-514页

作者： Z.M.Zheng b.wang School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Instimt Franco-Chinois de l'Energie Nucleaire Sun Yat-Sen UniversityZhuhai 519000China

Conventional heat transfer fluids usually have low thermal conductivity, limiting their efficiency in many applications. Many experiments have shown that adding nanosize solid particles to conventional fluids can greatly enhance their thermal conductivity. To explain this anomalous phenomenon, many theoretical investigations have been conducted in recent years. Some of this research has indicated that the particle agglomeration effect that commonly occurs in nanofluids should play an important role in such enhancement of the thermal conductivity, while some have shown that the enhancement of the effective thermal conductivity might be accounted for by the structure of nanofluids, which can be described using the radial distribution function of particles. However, theoretical predictions from these studies are not in very good agreement with experimental results. This paper proposes a prediction model for the effective thermal conductivity of nanofluids, considering both the agglomeration effect and the radial distribution function of nanoparticles. The resulting theoretical predictions for several sets of nanofluids are highly consistent with experimental data.

关键词： Nanofluid Thermal conductivity Modeling Agglomeration Radial distribution function

Generalized Second Law of Thermodynamics in Parabolic LTb Inhomogeneous Cosmology

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Communications in Theoretical Physics 2015年第11期64卷 597-604页

作者： A.Sheykhi H.Moradpour K.Rezazadeh Sarab b.wang Physics Department and biruni Observatory College of SciencesShiraz University Research Institute for Astronomy and Astrophysics of Maragha(RIAAM) Department of Physics University of Kurdistan INPAC and Department of Physics Shanghai Jiao Tong University

We study thermodynamics of the parabolic Lemaitre-Tolman-bondi(LTb) cosmology supported by a perfect Suid *** model is the natural generalization of the Sat Friedmann-Robertson-Walker(FRW) universe,and describes an inhomogeneous universe with spherical *** reviewing some basic equations in the parabolic LTb cosmology,we obtain a relation for the deceleration parameter in this *** also obtain a condition for which the universe undergoes an accelerating phase at the present *** use the first law of thermodynamics on the apparent horizon together with the Einstein field equations to get a relation for the apparent horizon entropy in LTb *** find out that in LTb model of cosmology,the apparent horizon's entropy could be feeded by a term,which incorporates the effects of the *** consider this result and get a relation for the total entropy evolution,which is used to examine the generalized second law of thermodynamics for an accelerating *** also verify the validity of the second law and the generalized second law of thermodynamics for a universe filled with some kinds of matters bounded by the event horizon in the framework of the parabolic LTb model.

关键词： parabolic LTb cosmology thermodynamics entropy gen

Predictive fatigue crack growth law of high-strength steels

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Journal of Materials Science & Technology 2022年第5期100卷 46-50页

作者： H.F.Li P.Zhang b.wang Z.F.Zhang Laboratory of Fatigue and Fracture for Materials Shi-changxu Innovation Center for Advanced MaterialsChinese Academy of SciencesInstitute of Metal ResearchShenyang 110016China State Key Laboratory of Mechanical behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The fatigue resistance of metallic materials is generally attributed to both strength and ***,these properties are mutually exclusive in most *** theories like Paris’law only provide some data correlation schemes rather than a predictive capability,which cannot satisfactorily guide the anti-fatigue *** this study,for the first time,the predictive fatigue crack growth rate law is proposed by considering the effects of both strength and ***,a quantitative criterion is established for judging the fatigue crack resistance of high-strength *** predictive law would provide a unique view to the quantitative anti-fatigue design of metallic materials.

关键词： Fatigue crack growth Strength and toughness Paris’law High-strength steels

A practical model for efficient anti-fatigue design and selection of metallic materials:Ⅰ.Model building and fatigue strength prediction

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Journal of Materials Science & Technology 2021年第11期70卷 233-249页

作者： R.Liu P.Zhang Z.J.Zhang b.wang Z.F.Zhang Laboratory of Fatigue and Fracture for Materials Shi-changxu Innovation Center for Advanced MaterialsInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic *** this problem,a theoretical fatigue model is proposed in this study,the possible applications have also been *** results would be introduced in two serial papers,in which the first paper focuses on the model building and the applications on fatigue strength prediction;the second paper put emphasis on the influencing factors of the model parameters and the applications on fatigue strength *** this first paper,a theoretical model is proposed considering both the strength and plastic restrictions of fatigue *** the model builds up a brief relationship among yield strength(Y),tensile strength(T)and fatigue strength(F),it is named as the Y-T-F *** the verification with fatigue strength data covering various kinds of metallic materials and loading conditions,this Y-T-F model exhibits both generality and *** the Y-T-F model,the efficient fatigue strength prediction could be conducted by brief linear fitting and calculation,just through yield strength,tensile strength and several known fatigue strength ***,through its deduced Y-F model,the analytical formula of fatigue strength continuously changing with materials strengthening can be obtained,as well as the maximum value of fatigue strength and corresponding critical yield *** summary,the Y-T-F model would be useful for reducing the fatigue tests,thus providing new possibilities on the efficient anti-fatigue design and selection of metallic materials.

关键词： Yield strength Tensile strength Plasticity Fatigue strength Anti-fatigue design

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Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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Journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： J.A.Liu S.J.Liu b.wang W.b.Sun X.J.Liu Z.W.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for bionics-Jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),W-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 MJ/m^(3)to 10.97 MJ/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

Effect of Calcining Temperature on the Structure of Li_4Ti_5O_(12)

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复旦学报（自然科学版） 2007年第5期46卷 844-845页

作者： G.J.wang N.H.Zhao L.J.Fu b.wang Y.P.Wu Deparment of Chemistry & Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan University

1 Introduction Recently there had considerable interest in Li4Ti5O12 as a potential anode for use in Li-ion batteries. Usually, it was used as an anode combined with a high voltage cathode[1-5]. It has many advantages compared to the currently used graphite. For example, it presents virtually unlimited cycle life due to zero strain or volume change when lithium intercalates into and de-intercalates from[6]. Generally, Li4Ti5O12 was prepared by a solid-state reaction from stoichiometric amounts of Li2CO3...

关键词： Lithium-ion battery Li4Ti5O12 anode materials electrochemical property

N-phenylmaleimide as a New Ploymerizable Additive for Overcharge Protection of Lithium-ion batteries

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复旦学报（自然科学版） 2007年第5期46卷 843-页

作者： b.wang Q.Xia Y.P.Wu Deparment of Chemistry Fudan University

1 Results In persuit of better safety controls of lithium batteries,much efforts has been focused on the development of the internal and self-actuating overcharge protection *** report a novel electropolymerizable electrolyte additive for overcharge protection of lithium batteries. Electrochemical properties and overcharge behavior of NPM as a new polymerizable electrolyte additive for overcharge protection of lithium ion batteries are studied by cyclic voltammetry,charge-discharge measurements...

关键词： lithium ion battery overcharge protection electropolymerization additive

Study on the Characterization and Kinetics of Immobilized Lipase

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复旦学报（自然科学版） 2007年第5期46卷 782-页

作者： b.wang Y.P.wang Y.L.Wei Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical EngineeringNorthwest Normal University

1 Rusults Most enzymes, including lipase, play a key role in biotechnology, but their usage is quite limited because of poor recovery, yield, limited re-usability and rapid inactivation in the soluble state. Immobilization enzymes offer advantages over free enzymes because of the availability of a choice of batch or continuous processes, rapid termination of reactions, controlled product formation, ease of enzyme removal from the reaction mixture, and adaptability to various engineering *** this ...

关键词： lipase immobilized enzyme magnetic microsphere enzymatic activity kinetics

Effect of two-stage dehydration on retention of characteristic flavor components of flue-cured tobacco in rotary dryer

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Effect of two-stage dehydration on retention of characterist...

Mechanistic Study on Ni-Catalyzed Silylation of Aryl Methyl Ethers

中国烟草学会2017年学术年会

作者： W.K.Zhu Y.wang L.Y.Chen Z.G.wang b.Li b.wang Zhengzhou Tobacco Research Institute of CNTC Institute of Agricultural Products Processing Henan Academy of Agricultural Sciences

Two-stage dehydration method of flue-cured tobacco in rotary dryer was experimentally evaluated and compared to the single-stage dehydration process. The characteristic flavor components in dried cut tobacco, including major Maillard reaction compounds and carotenoid degradation products, as well as drying rate were analyzed for different two-stage dehydration operations. The results showed that both the pre-drying temperature and intermediate moisture content had a significant effect on the overall drying rate of cut tobacco during two-stage drying. On the other hand, the retention of characteristic flavor components in tobacco, especially Maillard reaction compounds retention, was influenced significantly by the final drying temperature as well as intermediate moisture content. The 10°C increase in the final drying temperature from 100 to 110°C reduced the retentions of Maillard reaction compounds and carotenoid degradation products by 14.5 and 9.4%, respectively. Change of intermediate moisture contents from 19 to 15% reduced the Maillard reaction compounds retention by 14.7%. Given the consideration of characteristic flavor components’ retention and drying process efficiency, two-stage dehydration of cut tobacco in rotary dryer could reach a better performance as compared with the single-stage dehydration. The cylinder-wall temperature combination of 140/100°C with the 17% intermediate moisture content could be used as the optimal two-stage condition for the investigated flue-cured tobacco.

关键词： Flavor components flue-cured tobacco rotary dryer two-stage drying

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Mechanistic Study on Ni-Catalyzed Silylation of Aryl Methyl ...