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Flow of a micropolar fluid in a micro-ch.nnel under th. action of an alternating electric field: Estimates of flow in bio-fluidic devices

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j.urnal of h.drodynamics 2015年第3期27卷 350-358页

作者： MISRA j.C. Ch.NDRA S. h.RWIG h. Centre for h.alth.are Science and Tech.ology Indian Institute of Engineering Science and Technology Department of Ph.sics Sabang S. K. Mahavidyalaya Vidyasagar University Institute of Th.rmo-Fluid Dynamics Technische Universitat Hamburg-Harburg

Th. paper is devoted to a study of th. electro-osmotic flow of a micropolar bio-fluid, wh.n th. flow takes place between two plates th.t are in a state of periodic vibrations. Considering blood as a micropolar fluid, it is found th.t th. amplitude of oscillation of th. microparticles of blood increases wh.n th. micropolar effect is pronounced more and more and th.t a rise in Debyeh.ickel parameter enh.nces both.th. velocity and microrotation gradient. Th. results provide guidelines for th. improvement of design of bio-sensing and micro-fluidic devices. Th. study leads to th. conclusion th.t electrical double layers formed in th. vicinity of th. wall can significantly alter th. flow dynamics of ph.siological fluids in micro-bio-fluidic devices.

关键词： microrotation Electro-osmotic flow Debye-h.ickel parameter micropolar fluid

Electromagnetoelastic beh.viors of functionally graded piezoelectric solid cylinder and sph.re

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Acta Mech.nica Sinica 2007年第1期23卷 55-63页

作者： h. L. Dai Y.M. Fu j.h. Yang Department of Engineering Mech.nics Hunan University Changsha 410082 China

Analytical studies on electromagnetoelastic beh.viors are presented for th. functionally graded piezoelectric material （FGPM） solid cylinder and sph.re placed in a uniform magnetic field and subj.cted to th. external pressure and electric loading. Wh.n th. mech.nical, electric and magnetic properties of th. material obey an identical power law in th. radial direction, th. exact displacements, stresses, electric potentials and perturbations of magnetic field vector in th. FGPM solid cylinder and sph.re are obtained by using th. infinitesimal th.ory of electromagnetoelasticity. Numerical examples also sh.w th. significant influence of material inh.mogeneity. It is interesting to note th.t selecting a specific value of inh.mogeneity parameter β can optimize th. electromagnetoelastic responses, wh.ch.will be of particular importance in modern engineering designs.

关键词： Functionally graded piezoelectric material (FGPM) Electromagnetoelastic Solid cylinder Solid sph.re Perturbation of magnetic field vector

Th. Ch.racterization of Sputtered Zr-Ge-N Th.n Films as Diffusion Barriers Between Copper and Silicon

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稀有金属材料与工程 2012年第S1期41卷 120-123页

作者： Yang, j. j. Liu, B. Liao, X. D. j.ao, G. h. Xu, K. W. Sich.an Univ Inst Nucl Sci & Technol Minist Educ Key Lab Radiat Phys & Technol Chengdu 610064 Peoples R China CAS Xian Inst Opt & Precis Mech State Key Lab Transient Opt & Photon Xian 710049 Peoples R China Xi An j.ao Tong Univ State Key Lab Mech Behav Mat Xian 710049 Peoples R China

Th. main purpose of th. present micro-structural analysis by transmission electron microscopy(TEM)and X-ray diffraction(XRD)was to investigate wh.th.r amorph.us Zr-Ge-N films are a potential candidate as a diffusion barrier for Cu wiring used in Si *** Zr-Ge-N films were prepared by a radio frequency(RF)reactive magnetron sputter-deposition tech.ique using N2 and Ar mixed gas,and th. film structure was found to be sensitive to th. gas flow ratio of N2 *** during *** Zr-Ge-N films were obtained wh.n th. N2/(Ar+N2)ratio was smaller th.n 0.2 and amorph.us-like Zr-Ge-N films were obtained wh.n th. ratio was larger th.n *** barrier test was performed by annealing th. Cu/Zr-Ge-N/Si film stack under Ar *** deposited Zr-Ge-N(C)films remained amorph.us even after h.gh.temperature *** Cu diffusion profile in th. film was assessed by th. Auger electron spectroscopy(AES).Th. results indicate th.t Cu diffusion was minimal in amorph.us Zr-Ge-N(C)films even at h.gh.annealing temperatures of 800℃.

关键词： Zr-Ge-N films diffusion barrier micro-structural th.rmal stability

ON Th. DYNAMIC Ch.RACTERISTICS OF MOULD-FILLING UNDER COUNTERGRAVITY

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Acta Metallurgica Sinica(English.Letters) 1997年第5期10卷 409-414页

作者： Zeng, j.M. Gu, h. Zh.u, Y.h. Guangxi Univ Nanning China

In th.s paper, th. math.matical models for mould-filling under countergravity are derived on th. basis of th. principle of momentum. Dynamic processes of mould-filling are observed on a perspex model by means of h.gh.speed ph.tograph.. Th. results indicate th.t th. mould-filling under countergravity can be described by th. second order nonlinear differential equations ch.racterized by damping oscillations. Th. velocity oscillations amplify as th. pressuring speed increases if th. pressure differential functions are of th. same type. On th. oth.r h.nd, if th. functions are of different type, th.n th. velocity oscillations depend upon wh.th.r th. functions progressively increase or decrease. Velocity oscillations can be diminish.d dramatically by increasing th. local damping with.n th. gating system.

关键词： casting mould-filling dynamics

Optimization of Casting Process for h.at and Abrasion Resistant Large Gray Iron Castings

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Tsingh.a Science and Tech.ology 2008年第2期13卷 152-156页

作者： S. M. Yoo Y. S. Ch. C. C. Lee j. h. Kim C. h. Kim j. K. Ch.i Center for E-Design Korea Institute of Industrial Technology Kwangh.e Casting Mfg. Co. R&D Center Doosan Engine Co. Ltd.

Numerical simulations were used to optimize th. casting design and conditions for large cast iron castings for marine engines, Simulations of th. mold filling and solidification sequences were used to analyze th. problems of previous casting conditions with.marked improvements for large cylinder liner parts, Th. amount and positions of ch.lls were optimized to improve th. mech.nical properties and to minimize th. sh.inkage and micro porosity in th. castings. Ultra sonic testing, penetration testing, and mech.nical property testing sh.w no defects in th. castings with.th. productivity significantly increased.

关键词： gray cast iron numerical simulation marine engine cylinder liner ch.ll casting design optimization

Trace element ch.racteristics of partial melts produced by melting of metabasalts at h.gh.pressures: Constraints on th. formation condition of adakitic melts

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Science Ch.na Earth.Sciences 2006年第9期49卷 915-925页

作者： j. Adam T.h. Green GEMOC National Key Centre Department of Earth.and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with.5 wt.% added h.O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quench.d glasses) + residual mineral assemblages of amph.bolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine maj.r and trace element compositions of th.se quench.d melts, respectively. Maj.r ele- ment compositions of all th. melts are tonalitic- trondh.emitic, similar to adakite. Th.ir trace element ch.racteristics are controlled by coexisting residual minerals. Signatures of adakite such.as h.gh.Sr/Y, low h.EE and negative Nb-Ta anomaly, etc. are present only in th. melts coexisting with.residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amph.bole-eclogite). Garnet leads to h.EE depletion in melts, wh.reas rutile controls Nb and Ta partitioning during th. partial melting and causes negative Nb-Ta anomaly in melts. Th.refore, in addition to garnet, rutile is also a necessary residual ph.se during th. generation of adakite or TTG magmas to account for th. negative Nb-Ta anomaly of th. magmas. Th. depth.for th. generation of adakite/TTG magmas via melting of metabasalt must be more th.n about 50 km based on th. approximate 1.5 GPa mini- mum-pressure for rutile stability in th. partial melting field of h.drous basalt.

关键词： trace element adakite/TTG magmas partial melting of metabasalt negativeNb-Ta anomaly rutile

CO oxidation under lean and stoich.ometric conditions over ceriazirconia with.very low metal contents(Cu,Co,Ag and Pt)

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j.urnal of Rare Earth. 2024年第9期42卷 1669-1681,I0002页

作者： j.C.Martínez-Munuera M.P.Yeste A.García-García MCMA Group Department of Inorganic Chemistry and Institute of MaterialsUniversity of AlicanteCarretera de San Vicente del Raspeig s/n03690San Vicente del RaspeigAlicanteSpain Solid Ch.mistry and Catalysis Group Department of Materials ScienceMetallurgic Engineering and Inorganic ChemistryInstitute of Electronic Microscopy and Materials ResearchUniversity of CádizAp.40E-11510Puerto RealCádizSpain

In th.s work,several ceria-zirconia based catalysts with.very lo w(and equimolar) metal contents were prepared,ch.racterised and tested for th. CO oxidatio n reaction(under lean and stoich.ometric conditions),trying to emulate th.se conditions found in a diesel oxidation catalyst(DOC) system from a diesel engine and th.se encountered under gasoline exh.ust(λ=1).Th. metals ch.sen are Cu,Co,Ag and Pt(as a reliable bench.ark).Th. results reveal enormous differences among reducibility and catalytic activity despite quite similar structural and textural properties of th. catalysts,sh.wing differences among dispersion(Ag-catalyst seems to present a low level of dispersion).Th.s catalyst seems to be ch.racterised,as well,by a strong electronic interaction between Ce and Ag centres wh.ch.is suggested to yield an improved reducibility under h.(2)-TPR ***,th. order in catalytic activity(Cu>Ag>Co≈Pt>>support) seems not to follow th. order found in reducibility and th. Cu-catalyst seems to be th. most active independently on th. reaction conditions,yielding nearly overlapped CO oxidation catalytic *** restingly,a stro ng correlation between th. catalytic activity under th. two conditions tested and th. OSC values of th. Ce_(0.8)Zr_(0.2)O_(2)-supported metal catalysts is ***,OSC parameter measured at 150℃ can be used as a relevant descriptor to evaluate th. CO oxidation activity at low and medium conversions for th. investigated catalysts,much.better th.n th. h.(2)-TPR measurements.

关键词： CO oxidation Low metal content Ceria-zirconia Copper species OSC parameter Rare earth.

An Improvement on th. Efficiency of a Single Rotor Transonic Compressor by Reducing th. Sh.ck Wave Strength.on th. Blade Suction Surfaces

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j.urnal of Th.rmal Science 2012年第2期21卷 127-135页

作者： S. j. Geng N. X. Ch.n h. W. Zh.ng W. G. h.ang Institute of Engineering Th.rmoph.sics Chinese Academy of Sciences EO. Box 2706 Beijing 100190 China

It is well known th.t increasing th. rotational velocity is an effective way to increase th. total pressure ratio. With.increasing flow velocity especially under th. condition of transonic flow in th. supersonic region, wh.re exist strong sh.ck waves, th. sh.ck wave loss becomes main and important. Simultaneously, th.re occurs boundary layer separation due to th. sh.ck wave / boundary layer interaction. In th. present paper th. transonic compressor blades were studied and analyzed to find a proper and simple way to reduce th. sh.ck wave loss by optimizing th. suction surface configuration or controlling th. gradient of isentropic Mach.number on th. suction surface. A Navier-Stokes solver combined with.a modified design algorith. was developed and used. Th. NASA single rotor for transonic flow compressor was served as a numerical example to sh.w th. effectiveness of th.s meth.d. Two cases for both.original and modified rotors were analyzed and compared.

关键词： Transonic compressor sh.ck wave loss efficiency improvement blade optimization

Growth.of Structured Non—crystalline Boron—Oxygen—Nitrogen Films and Measurement of Th.ir Electrical Properties

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Ch.nese Ph.sics Letters 2003年第3期20卷 414-416页

作者：陈广超 j.-h.Boo Sch.olofMaterialScienceandEngineering UniversityofScineceandTechnologyBeijingBeijing100083 DepartmentofCh.mistry SungkyunkwanUniversitySuwon.440-746Korea

Th. boron-oxygen-nitrogen (BON) films h.ve been grown on Si wafer by th. low-frequency rf-plasma-enh.nced metal-organic ch.mical vapour deposition meth.d. Th. h.mogeneous film structure of completely amorph.us BON is first fabricated on a low-temperature-made buffer at 500°C with.N2 plasma and is observed with.a h.gh.resolution-electron microscope by th. transmission-electron diffraction. Th. results sh.w th.t th. interfaces among substrate/buffer/film are clear and straigh. in th. structured film. A h.terogeneous film containing nano-sized crystalline particles is also grown by a routine growth.procedure as a referential structure. Th. C-V ch.racteristic is measured on both.th. amorph.us and crystal-containing films by using th. metal-oxide-semiconductor structure. Th. dielectric constants of th. films are, th.refore, deduced to be 5.9 and 10.5 for th. amorph.us and crystal-containing films, respectively. Th. C-V results also indicate th.t more trapped ch.rges exist in th. amorph.us film. Th. binding energy of th. B, O, and N atoms in th. amorph.us film is h.gh.r th.n th.t in th. crystal-containing one, and th. N-content in th. latter is found to be h.gh.r th.n th.t in th. former by x-ray ph.to-electron spectroscopy. Th. different electrical property of th. films is th.ugh. to originate from th. energy state of th. covalent electrons.

关键词： Binding energy