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Current status of duplex surface engineered ti-based materials

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中国有色金属学会会刊：英文版 2004年第z1期14卷 6-12页

作者： t.Bell School of Engineering (Metallurgy and Materials) The University of Birmingham Birmingham B15 2TT UK

Industrial exploitation of the high specific strength and corrosion resistance of titanium were dominated historically by the technological advances which have been made in gas-turbine engine and aircraft components. Realization of the possible benefits in general engineering has been limited by the absence of any proven and reliable means of overcoming the poor wear resistance and galling tendency suffered by titanium alloys when in contact with other materials. this problem can only be addressed by optimizing and demonstrating industrially viable surface engineering processes for titanium in general engineering. the status of single and duplex surface engineering systems are reviewed. In addition, in order to fully realize the potential of advanced surface engineering of titanium components contact mechanics models are developed to enable the automotive engineers to design dynamically the loaded automotive engine and transmission components.

关键词： ti-based material specific strength corrosion resistance

Development of the PARASOL Code and Full Particle Simulation of tokamak Plasma with an Open-Field SOL-Divertor Region Using PARASOL

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Plasma Science and technology 2011年第3期13卷 316-325页

作者： t. tAKIZUKA Japan Atomic Energy Agency Naka Fusion Institute Naka 311-0193 Japan

the PARASOL code and the simulation by using PARASOL are introduced briefly. the PARASOL code with particle-in-cell （PIC） method and binary collision model was developed in JAERI and JAEA. Simulations using PARASOL code were carried out in order to investigate the power and particle control with diveror system in fusion reactors. the one-dimensional （1D） version of PARASOL was adopted to investigate the Bohm criterion, the supersonic flow, the SOL heat conduction, and so on. the heat propagation due to edge localized mode （ELM） was studied with the 1D-dynamic PARASOL. the two-dimensional version of PARASOL for the whole tokamak plasma including scrape-off-layer （SOL）-divertor region was useful for simulating the SOL flow pattern, the electric field formation etc. Based on PARASOL simulation results, improved physics modeling for the fluid simulation was built up.

关键词： tolkamak plasma scrape-off layer divertor sheath heat transport plasmaflow radial electric field particle simulation collision model

Contemplation on some cyclic N_8 isomers-A DFt treatment

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Defence technology（防务技术） 2018年第1期14卷 19-27页

作者： Lemi türker Middle East technical University Department of Chemistry

Various cyclic N_8 isomers are considered at the levels of B3 LYP/6-311++G(d,p) and B3 LYP/c PVtZ. Some energies and molecular orbital properties are obtained. the structures are found to be stable in the singlet state but mostly unstable in the triplet. the heats of formation values calculated by means of t1 recipe reveals that they are highly endothermic. NICS(0) values have been calculated and aromaticity/antiaromaticity of the rings are discussed. Additionally, theoretical IR,UV-VIS spectra and the calculated impulse values have been obtained.

关键词： Polynitrogen compounds Cyclic octanitrogen structures NICS Explosives Specific impulse DFt calculations

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EXACt SOLUtIONS OF A DIPOLAR FLUID FLOW

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Acta Mechanica Sinica 2003年第4期19卷 308-314页

作者： t.HAYAt DepartmentofMathematics Quaid-i-AzamUniversityIslamabad44000Pakistan

Exact solutions for three canonical flow problems of a dipolar fluid are obtained: (i) the flow of a dipolar fluid due to a suddenly accelerated plate, (ii) the flow generated by periodic oscillation of a plate, (iii) the flow due to plate oscillation in the presence of a transverse magnetic field. the solutions of some interesting flows caused by an arbitrary velocity of the plate and of certain special oscillations are also obtained.

关键词： unsteady flows dipolar fluid periodic oscillations MHD flow

Large deformation plasticity From basic relations to finite deformation

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Acta Mechanica Sinica 2020年第2期36卷 472-492页

作者： Otto t.Bruhns Institute of Mechanics Ruhr-University Bochum44780 BochumGermany

the theory of plasticity as a special field of continuum mechanics deals with the irreversible,***,deformation of *** the action of given loads or deformations,the state of the stresses and strains or the strain rates in these bodies is *** this way,it complements the theory of elasticity for the reversible behavior of *** practice,it has been observed that many materials behave elastically up to a certain load(yield point),beyond that load,however,increasingly plastic or *** combination of these two material properties is known as *** classical elastoplastic material behavior is assumed to be time-independent or *** contrast,we call a time-or rate-dependent behavior visco-elastoplastic and visco-plastic—if the elastic part of the deformation is *** plasticity theory,because of the given loads the states of the state variables stress,strain and temperature as well as their changes are *** this purpose,the observed phenomena are introduced and put into mathematical *** constitutive relations describing the specific material behavior are finally embedded in the fundamental relations of continuum theory and ***,the theory of plasticity was introduced in order to better estimate the strength of *** analysis based purely on elastic codes is not in a position to do this,and can occasionally even lead to incorrect *** the other hand,the entire field of forming techniques requires a theory for the description of plastic *** from the classical description of plastic behavior with small deformations,the present review is intended to provide an insight into the state of the art when taking into account finite deformations.

关键词： Finite deformation Elasto-plasticity Constitutive relations thermodynamics History of plasticity

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Preparation of microparticles and nanoparticles using membrane-assisted dispersion,micromixing,and evaporation processes

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Particuology 2024年第1期84卷 30-44页

作者： Goran t.Vladisavljevic Chemical Engineering Department Loughborough UniversityLoughboroughLeicestershire LE113TUUnited Kingdom

Synthetic microporous membranes are increasingly used for energy-efficient and controlled production of micro-and nanoparticles and micro-and nanoemulsions with tuneable morphology and physico-chemical properties through various micromixing,emulsification,and evaporation *** emul-sification processes,the membrane pores are used for dispersed phase injection and size-controlled generation of droplets and droplet-templated *** micromixing processes,membrane is utilised as a micromixer for mixing two miscible liquids,usually solvent and antisolvent-rich solutions,which leads to the creation of supersaturation and subsequent nanoprecipitation or *** mem-brane evaporation processes,membrane is used to prevent phase dispersion while allowing efficient molecular diffusion of solvent and/or antisolvent vapour through gas-filled *** dispersion processes can be operated continuously by decoupling shear stress on the membrane surface from cross flow using tube insets,flow pulsations,swirling flow,membrane oscillations or membrane *** generation and solidification can be performed continuously in a single pass by connecting membrane module with a downstream *** dispersion processes can be used for pro-duction of nanoparticles such as nanovesicles(liposomes,micelles,ethosomes,and niosomes),nanogels,polymeric,lipid and metallic nanoparticles,and *** main advantages of membrane-assisted particle generation are in low energy consumption,controlled geometry and hydrodynamic conditions at the microscale level,flexible throughput due to modular and scalable design of membrane devices,and a wide choice of available microporous membranes with various wall porosities,wetta-bilities,pore sizes,and pore morphologies to suit different applications.

关键词： Nanoparticles Microparticles Nanoemulsions Microemulsions Microporous membrane Crystallisation Flash nanoprecipitation Emulsification Zero liquid discharge

Investigation of structural,magnetic and optical properties of rare earth substituted bismuth ferrite

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Journal of Rare Earths 2013年第4期31卷 370-375页

作者： t.Durga Rao t.Karthik Saket Asthana Advanced Functional Materials Laboratory Department of PhysicsIndian Institute of Technology Hyderabad Department of Materials Science and Engineering Indian Institute of Technology Hyderabad

Polycrystalline BiFeO3 and rare earth substituted ***3 （BRFO, R=Y, Ho and Er） compounds were prepared by rapid solid state sintering technique. Structural phase analysis indicated that all the compounds stabilized in rhombohedral structure （R3c space group） and a small orthorhombic phase fraction was observed in BRFO compounds. From the Raman spectra results, the changes in the phonon frequencies （A1） and line widths suggested lattice distortion in the BRFO compounds as was evidenced in the XRD analysis. Compared to the linear variation of magnetization with magnetic field （M-H） shown by BFO, an obvious M-H loop was observed in BRFO compounds which could be due to the suppression of space modulated spin structure and was explained on the basis of weak ferromagnetism and field induced spin reorientation. UV-Vis spectroscopy evidenced a change in local FeO6 envi- ronment due to shift in the 6Alg→4t2g energy transition band. BRFO compounds with improved remnant magnetization and coercive field are applicable for magnetoelectric devices.

关键词： structural distortion spin-reorientation G-type antiferromagnet rare earths

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the tendency toward Higher Integration of *** Problems for Copper Based Lead Frame Materials

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功能材料 1993年第2期24卷 100-105页

作者： t Sakamoto Japan Electronic Materials Society Japan 本刊通讯编委

the inereasing market needs forthe VLSI(Very Large Scale IntegratedCircuit)can be classified as follows:(1)Higher packaging dellsity(2)More advanced and multifarious

关键词： the tendency toward Higher Integration of I.C.and Problems for Copper Based Lead Frame Materials 功能材料