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j.urnal of Forestry Research 2015年第3期26卷 571-579页

作者： Gasto Viegas de Pinh. j.nior AndréR. Terra Nascimento Barbara Tah.ra Valverde Lucas h. Clemente Elementary/h.gh.Sch.ols in Uberlndia UberlndiaMinas Gerais 38412-436 Brazil Universidade Federal de Uberlndia UberlndiaMinas Gerais 38412-436 Brazil Avenida Ortizio Borges 2836 Bairro Santa MnicaUberlndia Minas Gerais 38412-436 Brazil

In th.s paper we analyze and compare natural regeneration in sh.ub-tree community in th.ee areas below Pinus caribaea stands and a natural area （cerrado sensu stricto）. We also analyze th. influence of bioph.sical and environmental variables on th. distribution of regenerating sh.ub-tree species. Th. areas were analyzed and compared in relation to dispersal syndromes as well, being zooch.ry and anemoch.ry th. prevailing syndroms in th. four areas. Th. sites below P. caribaea sh.w a h.terogeneous regen- eration with.th. number of species ranging from 18 to 42. We analyzed th. influence of th. bioph.sical and envi- ronmental variables performing a canonical correspon- dence analyses, being found significant values for variables distance from remnant and basal area. Th. species Si- paruna guianensis, Miconia albicans, Xylopia aromatica, Sclerolobium paniculatum, Casearia sylvestris and P. caribaea were th. most importante ones in th. four areas,

关键词： Native regeneration Cerrado Commercialforests Multivariate analysis Plant ecology

Synth.sis of RE(Oh._2Cl and REOCl (RE=Eu, Tb) nanostructures

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j.urnal of Rare Earth. 2008年第2期26卷 131-135页

作者： S. V. Mah.j.n j. h.rt j. h.od A. Everh.art M. L. Redigolo D. S. Koktysh.E. A. Payzant j. h. Dickerson Interdisciplinary Program in Materials Science Vanderbilt UniversityNashville TN 37235 USAVanderbilt Institute of Nanoscale Science and Engineering Vanderbilt UniversityNashville TN 37235 USA department of Ph.sics and Astronomy Vanderbilt UniversityNashville TN 37235 USA department of Ph.sics and Astronomy Vanderbilt UniversityNashville TN 37235 USAVanderbilt Institute of Nanoscale Science and Engineering Vanderbilt UniversityNashville TN 37235 USA department of Ch.mistry Vanderbilt UniversityNashville TN 37235 USAVanderbilt Institute of Nanoscale Science and Engineering Vanderbilt UniversityNashville TN 37235 USA Center for Nanoph.se Materials Sciences Oak Ridge National LaboratoryOak Ridge TN 37831 USA

Anisotropic structures, nanoneedles, and nanospindles of rare earth.h.droxych.oride （RE（Oh.2Cl） and oxych.oride （REOCl）（rare earth.Eu and Tb） were synth.sized. Th. rare earth.h.droxych.oride nanostructures were formed via a th.rmally assisted h.drolysis of th. rare-earth.sesquioxide nanocrystals. Th. morph.logical evolution of th. nanostructures was studied using h.gh.resolution transmission electron microscopy and scanning electron microscopy, wh.le th. structural evolution was investigated using X-ray diffraction tech.iques. Th. th.rmal stability of th. rare earth.h.droxych.orides was investigated using th.rmogravimetric analysis. Th. rare earth.oxych.oride nanospindles were synth.sized via a simple h.at-treatment of rare earth.h.droxych.oride nanospindles.

关键词： rare-earth.h.droxych.oride rare-earth.oxych.oride rare earth.sesquioxide nanoneedle nanospindle lanth.nide

Fluctuating h.drodynamic meth.ds for fluid-structure interactions in confined ch.nnel geometries

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Applied Math.matics and Mech.nics(English.Edition) 2018年第1期39卷 125-152页

作者： Y. WANG h. LEI P.j. ATZBERGER department of Math.matics University of California Santa Barbara Santa Barbara CA 93106 U. S. A. Pacific North.estern National Laboratories Richland WA 99354 U. S. A.

We develop computational teractions subj.ct to th.rmal fluctuations geometry. Th. meth.ds take into account meth.ds for th. study of fluid-structure in- wh.n confined with.n ch.nnels with.slit-like th. h.drodynamic coupling and diffusivity of microstructures wh.n influenced by th.ir proximity to no-slip walls. We develop stoch.s- tic numerical meth.ds subj.ct to no-slip boundary conditions using a staggered finite volume discretization. We introduce tech.iques for discretizing stoch.stic systems in a manner th.t ensures results consistent with.statistical mech.nics. We sh.w h.w an exact fluctuation-dissipation condition can be used for th.s purpose to discretize th. stoch.stic driving fields and combined with.an exact proj.ction meth.d to enforce incompressibil- ity. We demonstrate our computational meth.ds by investigating h.w th. proximity of ellipsoidal colloids to th. ch.nnel wall affects th.ir active h.drodynamic responses and passive diffusivity. We also study for a large number of interacting particles collective drift-diffusion dynamics and associated correlation h.actions. We expect th. introduced stoch.stic computational meth.ds to be broadly applicable to applications in wh.ch.con- finement effects play an important role in th. dynamics of microstructures subj.ct to h.drodynamic coupling and th.rmal fluctuations.

关键词： fluctuating Eulerian-Lagrangian meth.d h.drodynamics immersed (SELM) ellipsoidal colloid boundary meth.d stoch.stic mobility nanoch.nnel

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

Sh.rtening th. Duration of h.at Treatment in th. Lower Bainitic Range

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材料热处理学报 2004年第5期25卷 555-560页

作者： h. Vetters h.-W. Zoch Foundation Institute for Materials Science Bremen GermanyFoundation Institute for Materials Science Bremen Germany

In many cases an isoth.rmal treatment of th.ough.ardening bearing grades in th. lower bainitic range allows to adj.st th. mech.nical properties of mach.ne components to th. later application, similar to th.se of martensitic h.rdening. Th. ach.eved microstructure contains only a negligible amount of retained austenite, so a dimensional ch.nge of components during application can be reduced. One disadvantage of th. isoth.rmal bainitic treatment in salt bath.is th.t th. duration of th. treatment is much.longer th.n th.t of th. martensitic h.rdening and th.s causes h.gh.r costs. Th.refore it would be desirable to be able to sh.rten th. transformation duration in th. lower bainitic range. Th. aim of th. present work is to determine th. parameters, by wh.ch.th. process could be greatly sh.rtened in comparison with.th. conventional transformation process in th. lower bainitic range. Th.refore th. bainitic transformation beh.vior of th. steel 100 Cr6 (SAE 52100) and th. relevant influence factors were investigated by means of dilatometry, in wh.ch.th. h.at treatments were carried out with.different process variants including pre-quench.ng or post-quench.ng. Th. amount of retained austenite in th. microstructure and th. h.rdness of th. steel after th. sh.rtened h.at treatments were measured. Finally th. possibility to use th.se processes in industrial production is discussed.

关键词：贝氏体轴承钢膨胀测定法热处理

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.0}mitic, 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