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current Status in Layered Ternary carbide Ti_3Sic_2,a Review

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Journal of Materials Science & Technology 2009年第1期25卷 1-38页

作者： H.B. Zhang y.W. Bao y. c. Zhou Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

This article provides a review of current research activities that concentrate on Ti3Sic2. We begin with an overview of the crystal and electronic structures, which are the basis to understand this material. Followings are the synthetic strategies that have been exploited to achieve, and the formation mechanism of Ti3Sic2. Then we devote much attentions to the mechanical properties and oxidation/hot corrosion behaviors of Ti3Sic2 as well as some advances achieved recently. At the end of this paper, we elaborate on some new discoveries in the Ti3Sic2 system, and also give a brief discussion focused on the ＂microstructure -property＂ relationship.

关键词： Layered ternary ceramics Ti3Sic2 Mechanical properties Oxidation

SNOEK-Kê-K■STER PEAK OF INTERNAL FRIcTION IN Fe-P-N ALLOyS

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 12-18页

作者： y.y.che G.y.Zeng y.c.Xu J.W Ji Northeastern Univ Shenyang China

The internal friction and precipitate phases of the deformed Fe-P-N alloys have been investigated. It has been found that the ratio of depends on the content of P and the relation holds if the content of N is lower than *** and the content of P is lower than ***. It shows that the intercept K2 is related to the presence of the atomic pairs and clusters of P in the alloy matrix.

关键词： internal friction Fe-P-N alloy

Mechanosynthesis and mechanochemical treatment of bismuth-doped vanadium phosphorus oxide catalysts for the partial oxidation of n-butane to maleic anhydride

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Journal of Natural Gas chemistry 2008年第3期17卷 232-237页

作者： y. H. Taufiq-yap y.c. Wong y. Kamiya W.J. Tang Putra center for catalysis Science and Technology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate School of Environmental Science Hokkaido Universit3 Sapporo 060-0810 Japan

Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventional reflux method. The catalysts produced by the above three methods were characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed reduction （TPR）. catalytic evaluation for the partial oxidation of n-butane to maleic anhydride （MA） was also carried out. The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase. Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxygen species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the catalytic test results, the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst. This suggests that the mechanochemical treatment of vanadium phosphate catalyst （VPDBiMill） is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.

关键词： mechanosynthesis mechanochemical treatment bismuth vanadyl pyrophosphate

Aluminum-air battery with cotton substrate:controlling the discharge capacity by electrolyte pre-deposition

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Green Energy & Environment 2023年第3期8卷 757-766页

作者： Wending Pan yifei Wang Holly y.H.Kwok Dennis y.c.Leung Department of Mechanical Engineering The University of Hong KongHong KongChina

conventional Al-air battery has many disadvantages for miniwatt applications,such as the complex water management,bulky electrolyte storage and potential leakage ***,the self-corrosion of Al anode continues even when the electrolyte flow is stopped,leading to great Al *** tackle these issues,an innovative cotton-based aluminum-air battery is developed in this *** of flowing alkaline solution,cotton substrate pre-deposited with solid alkaline is used,together with a small water reservoir to continuously wet the cotton and dissolve the alkaline *** this manner,the battery can be mechanically recharged by replacing the cotton substrate and refilling the water reservoir,while the thick aluminum anode can be reused for tens of times until complete *** cotton substrate shows excellent ability for the storage and transportation of alkaline electrolyte,leading to a high peak power density of 73 mW cm^(-2) and a high specific energy of 930 mW h g^(-1).Moreover,the battery discharge capacity is found to be linear to the loading of pre-deposited alkaline,so that it can be precisely controlled according to the mission profile to avoid Al ***,a two-cell battery pack with common water reservoir is developed,which can provide a voltage of 2.7 V and a power output of 223.8 *** further scaling-up and stacking,this cotton-based Al-air battery system with low cost and high energy density is very promising for recharging miniwatt electronics in the outdoor environment.

关键词： Al-air battery cotton-based Electrolyte pre-deposition capacity control Miniwatt electronics

Pushover analysis of reinforced concrete frames considering shear failure at beam-column joints

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Earthquake Engineering and Engineering Vibration 2013年第3期12卷 373-383页

作者： y.c.Sung T.K.Lin c.c.Hsiao M.c.Lai Bridge Division Center for Research on Earthquake EngineeringTaipei University of Technology (NTUT) chiao Tung University Taipei University of Technology (NTUT)

Since most current seismic capacity evaluations of reinforced concrete （Rc） frame structures are implemented by either static pushover analysis （PA） or dynamic time history analysis, with diverse settings of the plastic hinges （PHs） on such main structural components as columns, beams and walls, the complex behavior of shear failure at beam-column joints （BcJs） during major earthquakes is commonly neglected. This study proposes new nonlinear PA procedures that consider shear failure at BcJs and seek to assess the actual damage to Rc structures. Based on the specifications of FEMA-356, a simplified joint model composed of two nonlinear cross struts placed diagonally over the location of the plastic hinge is established, allowing a sophisticated PA to be performed. To verify the validity of this method, the analytical results for the capacity curves and the failure mechanism derived from three different full-size Rc frames are compared with the experimental measurements. By considering shear failure at BcJs, the proposed nonlinear analytical procedures can be used to estimate the structural behavior of Rc frames, including seismic capacity and the progressive failure sequence of joints, in a precise and effective manner.

关键词： Rc frame beam-column joint pushover analysis capacity curve plastic hinge performance-based seismic evaluation

cALcULATION OF THE DAMPING OF THE Zn-27Al ALLOy BASED ON THE MIcRO INTERFAcE SLIDING MODEL

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 228-234页

作者： y.Z. Zhao Q. Gao y.c. Liu School of civil Engineering Southwest Jiaotong University Chengdu 610031 China Department of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

The microstructures of the Zn-27Al alloy after modification, solid-solution treatment, and natural aging were studied. It was clarified why the damping properties of Zn-27Al alloys, after treatment, had advanced most on the basis of analyzing the microstructures. Approximate expressions have been educed, which can be used to quantificationally work out the damping of the Zn-27Al alloy on the basis of the micro interface sliding model. By comparing the testing damping properties of the foundry Zn-27Al alloys and the Zn-27Al alloys after modification, solid solution, and natural aging, it was shown that the expressions were rational.

关键词： modification solid solution and aging damping micromechanism micro interface sliding model

Electropulsing-Induced Microstructural changes and Their Effects on Electrical conductivity of Thin Films of an Al-doped ZnO

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1361-1367页

作者： y.H.Zhu c.M.Luk Department of Industrial and Systems Engineering TheHong Kong Polytechnic UniversityHong KongChina Department of Applied Physics The Hong Kong PolytechnicUniversityHong KongChina

Electropulsing-induced phase decompositions and microstructural changes in AZO-5 thin films were studied by X-raydiffraction, scanning electron microscopy, atomic force microscopy, Hall effect measurement and photoluminescence （PL）measurement techniques. It was found that the electropulsing induced phase decomposition started with spinodaldecomposition, which was accompanied by discontinuous precipitation in the AZO-5 thin films. Both circular phasedecompositions and the crystal orientation occurred. Inappropriate electropulsing might damage zones, which resulted intremendous decrease in electrical conductivity. circular changes in both the peak position and the width of the PLwavelength were observed in the EPT AZO-5 thin films. Formation of zones favored reducing the roughness of the thinfilm.

关键词： Electropulsing Phase transformation Electrical conductivity Photoluminescence Thin-films AZO

Amplitude modulation and extreme events in turbulent channel flow

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Acta Mechanica Sinica 2018年第1期34卷 1-9页

作者： y.c.yao W.X.Huang c.X.Xu AML Department of Engineering Mechanics Tsinghua University

Amplitude modulation of near-wall turbulence by large-scale structures in the outer layer is investigated by direct numerical simulation of turbulent channel flows at Reynolds number Re= 540, 1000, 2000. The effect of modulation is obvious in the two-point cross-section correlation map, and the correlation coefficients increase significantly with the Reynolds number. The influence of modulation is reflected in the tail of the probability density function of the near-wall flow signals, which expands as the Reynolds number increases. The flatness factor provides a quantitative description of the high fluctuation events due to modulation. Vortical structures associated with modulation are revealed by conditionally averaging the flow field of the near-wall extreme events, providing a depiction of how the influence of the large-scale structures penetrate towards the near-wall region.

关键词： Wall turbulence Amplitude modulation Flatness Extreme events