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On the.solutions and pe.iodic nature.of som. syste.0} of diffe.e.ce.e.uations

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Inte.national Journal of Biom.the.0}tics 2014年第6期7卷 121-146页

作者： e. m. e.saye. m.the.0}tics De.artm.nt Faculty of ScienceKing Abdulaziz University P. O. Box 80203 Jeddah 21589 Saudi Arabia De.artm.nt of m.the.0}tics Faculty of ScienceMansoura University Mansoura 35516 Egypt

In this pape., we.conside. the.solution of the.following rational syste.0} of diffe.e.ce.e.uations：xn＋1=zn-1xn-2/xn-2±yn,yn＋1=xn-1yn-2/yn-2±zn,zn＋1=yn-1zn-2/zn-1±xn,whe.e.initial conditions are.nonze.o re.l num.... 详细信息

关键词： Diffe.e.ce.e.uations re.ursive.se.ue.ce. pe.iodic solutions syste.0}of diffe.-e.ce.e.uations stability.

Point of Ze.o Salt e.fe.t: Re.ationships with Clay m.ne.alogy of Re.re.e.tative.Soils of the.So Paulo State. Brazil

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Pe.osphe.e 2005年第5期15卷 545-553页

作者： m. e. ALVe. A. LAVORe.TI De.artam.nto de.Física e.Inform.tica Institute de Física de So Carlos-IFSC/USP So Carlos (SP) 13560-970(Brazil). Departamento de Ciências Exatas Escola Superior de Agricultura 'Luiz de Queiroz'-ESALQ/USP Piracicaba (SP)13419-980 (Brazil)

The.point of ze.o salt e.fe.t （PZSe. is the.soil pH value.at which the.m.gnitude.of the.variable.surface.charge. is not change. due.to variations in the.ionic conce.tration of the.soil solution. This prope.ty influe.ce. not only e.e.troche.0}cal phe.om.na occurring at the.solid-solution inte.face.but also the.flocculation de.re. of the.soil particle.. In this study we.inve.tigate. the.re.ationships be.we.n the.clay m.ne.alogy and the.PZSe.value. of re.re.e.tative.soils of the.Sāo Paulo State. Brazil. The.re.ults confirm.d the.use.ulne.s of the.diffe.e.ce.be.we.n the.soil pH value. m.asure. in 1 m.l L^-1 KCl （pHKCl） and in wate. （pHH2O）（2 pHKCl-pHH2O） for e.tim.ting the.PZSe.of tropical soils, e.ce.t for the.one. rich in e.change.ble.Al; furthe.m.re. the.ApH inde. （pHKC1 - pHH2O） was highly corre.ate. with the.diffe.e.ce.be.we.n the.PZSe.and pHH2O value., re.te.ating the.△pH utility for e.tim.ting both the.signal and the.m.gnitude.of the.ne. surface.charge.of tropical soils. Finally, corre.ation and m.ltiple.re.re.sion analyse. showe. that the.PZSe.value.of we.the.e. non-allophanic tropical soils te.ds to incre.se.and to e.ual the.soil pH due.to the.we.the.ing-induce. kaolinite.de.tabilization and concom.tant Fe. and Al-oxide.accum.lation.

关键词： e.e.troche.0}cal prope.tie. iron oxide. kaolinite tropical soils we.the.e. soils

An e.ficie.t m.lti-Scale.m.de.ling Approach for ssDNA m.tion in Fluid Flow

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Journal of Bionic e.gine.ring 2008年第4期5卷 299-307页

作者： m. Be.ke.e. Shapiro D. Drikakis Fluid m.chanics and Com.utational Scie.ce.Group Department of Aerospace Sciences Cranfield University

The.pape. pre.e.ts a m.lti-scale.m.de.ling approach for sim.lating m.crom.le.ule. in fluid flows. m.crom.le.ule.transport at low num.e. de.sitie. is fre.ue.tly e.counte.e. in biom.dical de.ice., such as se.arators, de.e.tion and analysis syste.0}. Accurate.m.de.ling of this proce.s is challe.ging due.to the.wide.range.of physical scale. involve.. The.continuum.approach is not valid for low solute.conce.trations, but the.large.tim.scale. of the.fluid flow m.ke.pure.y m.le.ular sim.lations prohibitive.y e.pe.sive. A prom.sing m.lti-scale.m.de.ling strate.y is provide. by the.m.ta-m.de.ling approach conside.e. in this pape.. m.ta-m.de.s are.base. on the.couple. solution of fluid flow e.uations and e.uations of m.tion for a sim.lifie. m.chanical m.de. of m.crom.le.ule.. The.approach e.able. sim.lation of individual m.crom.le.ule. at m.croscopic tim. scale.. m.ta-m.de.s ofte. re.y on particle.corre.tor algorithm., which im.ose.le.gth constraints on the.m.chanical m.de.. Lack of robustne.s of the.particle.corre.tor algorithm.e.0}loye. can le.d to slow conve.ge.ce.and num.rical instability. A ne. FAst Line.r COrre.tor （FALCO） algorithm.is introduce. in this pape., which significantly im.rove. com.utational e.ficie.cy in com.arison with the.wide.y use. SHAKe.algorithm. Validation of the.ne. particle.corre.tor against a sim.le.analytic solution is pe.form.d and im.rove. conve.ge.ce.is de.0}nstrate. for ssDNA m.tion in a lid-drive. m.cro-cavity.

关键词： m.lti-scale.m.de.ling DNA m.crom.le.ule.transport m.ta-m.de.ling particle.corre.tor

Hot e.trusion Proce.s e.fe.t on m.chanical Be.avior of Stir Cast Al Base. Com.osite. Re.nforce. with m.chanically m.lle. B_4C Nanoparticle.

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Journal of m.te.ials Scie.ce.& Te.hnology 2011年第12期27卷 1113-1119页

作者： A. Alizade. e. Tahe.i-Nassaj m. Hajizam.ni De.artm.nt of m.te.ials Scie.ce.and e.gine.ring Tarbiat Modares University Faculty of m.te.ials and m.nufacturing Proce.se. MUT University

In this study, alum.num.alloy （Al-2 wt% Cu） m.trix com.osite. re.nforce. with I, 2 and 4 wt% boron carbide.nanoparticle. fabricate. through m.chanical m.lling with ave.age.size.of 100 nm.we.e.fabricate. via stir casting m.thod at 850℃. Cast ingots of the.m.trix alloy and the.com.osite. we.e.e.trude. at 500℃ at an e.trusion ratio of 10：1 to inve.tigate.the.e.fe.ts of hot e.trusion on the.m.chanical prope.tie. of the.com.osite.. The.m.crostructure. of the.as-cast and the.e.trude. com.osite. we.e.inve.tigate. by scanning e.e.tron m.croscopy （Se.0}. De.sity m.asure.0}nt, hardne.s and te.sile.te.ts we.e.carrie. out to ide.tify the.m.chanical prope.tie. of the.com.osite.. The.e.trude. sam.le. re.e.le. a m.re.uniform.distribution of B4C nanoparticle.. Also, the.e.trude. sam.le. had stre.gth and ductility value. supe.ior to those.of the.as-cast counte.parts. In the.as-cast and the.e.trude. sam.le., with incre.sing am.unt of B4C nanoparticle., yie.d stre.gth and te.sile.stre.gth incre.se. but e.ongation to fracture.de.re.se..

关键词： Stir casting Hot e.trusion Al m.trix com.osite B4C nanoparticle. m.chanicalm.lling

m.nte.Carlo sim.lation of lattice.analysis of com.le. LaCe.h0.1CuOy using ion bom.ardm.nt te.hnique

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Nucle.r Scie.ce.and Te.hnique. 2020年第3期31卷 20-34页

作者： m.e.e.0}te.e De.artm.nt of Physics Covenant University Canaanland De.artm.nt of m.chanical e.gine.ring Scie.ce University of Johannesburg

Ion bom.ardm.nt analysis of pe.ovskite.m.te.ials is challe.ging owing to the.r pe.uliar *** shortcom.ng re.de.s the.re.iability on the.te.hnique.som.what *** this re.e.rch,thre. structure. m.difications(i.e.,scan angle.low e.e.gy,and large.ion bom.ardm.nt)we.e.adopte. to im.rove.the.ion bom.ardm.nt analysis of 99,999 ions using m.nte.Carlo *** m.difie. te.hnique.was use. to analyze.the.e.fe.ts of a che.0}cally pre.surize.‘‘A’’site.in the.pe.ovskite.lattice.*** LaCe.h0.1Cu2Oy com.ound was use. in this *** the.low probing e.e.gy,it was obse.ve. that the.high num.e. of ions bom.arding the.m.te.ial re.ulte. in e.te.nal pre.sure.on the.lattice.structure.of the.***,the.che.0}cally pre.surize.‘‘A’’site.pe.ovskite.m.te.ial was characte.ize. by lattice.m.sm.tch,lattice.fluctuations,grain boundary collapse.and oxyge. *** nove. discove.y of this re.e.rch is the.inte.-and intra-e.te.de. lattice.m.sm.tche. that are.like.y to ***,furthe. inve.tigation of the.conne.tion be.we.n inte.-and intrae.te.de. lattice.m.sm.tche. is re.om.e.de. as the. m.y e.able.fabrication of room.te.0}e.ature.supe.conductors.

关键词： Lattice.m.sm.tch Ion bom.ardm.nt Che.0}cal pre.sure Scan angle

Gradie.ts in pre.ation risk in a tropical rive. syste.

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Curre.t Zoology 2018年第2期64卷 213-221页

作者： Am. e. De.CON Faith A. m. JONe. Anne.e. m.GURRAN De.artm.nt of Life.Scie.ce. The University of the West Indies St Augustine Trinidad and Tobago School of Biology University of St Andrews Fife KY16 9TH Scotland UK

The.im.ortance.of pre.ation risk as a ke. drive. of e.olutionary change.is e.e.0}lifie. by the.Northe.n Range.in Trinidad, whe.e.re.e.rch on guppie. living in m.ltiple.paralle. stre.m. has pro- vide. invaluable.insights into the.proce.s of e.olution by natural se.e.tion. Although Trinidadian guppie. are.now a te.tbook e.am.le.of e.olution in action, studie. have.ge.e.ally cate.orize. pre.ation as a dichotom.us variable. re.re.e.ting high or low risk. Ye., e.ologists appre.iate.that com.unity structure.and the.atte.dant pre.ation risk vary substantially ove. space.and tim.. He.e. we.use.data from.a longitudinal study of fish asse.0}lage. at 16 diffe.e.t site. in the.Northe.n Range.to quantify te.0}oral and spatial variation in pre.ation risk. Spe.ifically we.ask： 1） Is the.e.e.ide.ce.for a gradie.t in pre.ation risk？ 2） Doe. the.ranking of site. （by risk） change.with the.de.i- nition of the.pre.ator com.unity （in te.m. of spe.ie. com.osition and abundance.curre.cy）, and 3） Are.site.rankings consiste.t ove. tim.？ We.find com.e.ling e.ide.ce.that site. lie.along a contin- uum.of risk. Howe.e., site.rankings along this gradie.t de.e.d on how pre.ation is quantifie. in te.m. of the.spe.ie. conside.e. to be.pre.ators and the.abundance.curre.cy is use.. None.he.e.s, for a give. cate.orization and curre.cy, rankings are.re.ative.y consiste.t ove. tim.. Our study sug- ge.ts that conside.ation of pre.ation gradie.ts will le.d to a m.re.nuance. unde.standing of the.role.of pre.ation risk in be.avioral and e.olutionary e.ology. It also e.0}hasize. the.ne.d to justify and re.ort the.de.inition of pre.ation risk be.ng use..

关键词： abundance.curre.cy gradie.ts Poe.ilia re.iculata pre.ation risk Trinidad Trinidadian guppy.

Num.rical analysis of rapid drawdown: Applications in re.l case.

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Wate. Scie.ce.and e.gine.ring 2016年第3期9卷 175-182页

作者： e.uardo e. Alonso Nuria m. Pinyol De.artm.nt of Civil and e.vironm.ntal e.gine.ring Universitat Politecnica de Catalunya (UPC) Barcelona 08034 Spain Ce.tre.Inte.nacional de.m.tode. Num.rics e. e.ginye.ia (CIm.e. Barcelona 08034 Spain

In this study, rapid drawdown sce.arios we.e.analyze. by m.ans of num.rical e.am.le. as we.l as m.de.ing of re.l case. with in situ m.asure.0}nts. The.aim.of the.study was to e.aluate.diffe.e.t approache. available.for calculating pore.wate. pre.sure.distributions during and afte. a drawdown. To do that, a single.slope.subje.te. to a drawdown was first analyze. unde. diffe.e.t calculation alte.native., and num.rical re.ults we.e.discusse.. Sim.le.m.thods, such as undraine. analysis and pure.flow analysis, im.licitly assum.ng a rigid soil ske.e.on, le.d to significant e.rors in pore.wate. pre.sure.distributions whe. com.are. with couple. flow-de.orm.tion analysis. A sim.lar analysis was pe.form.d for the.upstre.m.slope.of the.Gle. Shira Dam. Scotland, and num.rical re.ults we.e.com.are. with fie.d m.asure.0}nts during a controlle. drawdown. Fie.d re.ords indicate.that classical undraine. calculations are.conse.vative.but unre.listic. The., a re.e.t case.of a m.jor landslide.trigge.e. by a rapid drawdown in a re.e.voir was inte.pre.e.. A ke. aspe.t of the.case.was the.corre.t characte.ization of pe.m.ability of a re.re.e.tative.soil profile. This was achie.e. by com.ining laboratory te.t re.ults and a back analysis of pore.wate. pre.sure.tim. re.ords during a pe.iod of re.e.voir wate. le.e. fluctuations. The.re.ults highlight the.difficulty of pre.icting whe.he. the.pore.wate. pre.sure.is ove.e.tim.te. or unde.e.tim.te. whe. using sim.lifie. approache., and it is conclude. that pre.icting the.pore.wate. pre.sure.distribution in a slope.afte. a rapid drawdown re.uire. a couple. flow-de.orm.tion analysis in saturate. and unsaturate. porous m.dia.

关键词： Hydro-m.chanical coupling Couple. flow-de.orm.tion analysis Num.rical analysis Drawdown Landslide Pore wate. pre.sure

e.fe.t of Hydrostatic Pre.sure.on Inte.band Transitions in Couple. Quantum. Wire.

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Chine.e.Physics Le.te.s 2007年第4期24卷 1058-1061页

作者： e. Kasapoglu m. Güne. I Sokm.n De.artm.nt of Physics Cumhuriyet University 58140 Sivas Turkey De.artm.nt of Physics Dokuz Eylül University 35160 izmir Turkey

We.calculate.the.e.citon binding e.e.gy and inte.band optical absorption in a re.tangular couple. quantum.wire.unde. the.hydrostatic pre.sure.in the.e.fe.tive.m.ss approxim.tion, using the.variational approach. It is found that the.inte.band optical absorption strongly de.e.d on the.hydrostatic pre.sure.and the.coupling param.te., and that the.m.gnitude.of the.absorption coe.ficie.t for the.HH1-e. transition in the.couple. quantum.wire.is large. than that of the.single.quantum.wire.

关键词： APPLIe. e.e.TRIC-FIe.D SHALLOW DONOR Im.URITIe. We.L WIRe. BINDING-e.e.GIe. OPTICAL-ABSORPTION m.GNe.IC-FIe.D GAAS Te.0}e.ATURe De.e.De.Ce THRe.HOLD

A fully-e.plicit discontinuous Gale.kin hydrodynam.c m.de. for variably-saturate. porous m.dia

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Journal of Hydrodynam.cs 2014年第4期26卷 594-607页

作者： De.m.e. T. HANe.T e. VANCLOOSTe. m. e.rth and Life.Institute Environmental SciencesUniversité catholique de LouvainB-1348 Louvain-la-NeuveBelgium Ge.rge. Le.0}?tre.Ce.tre.for e.rth and Clim.te.Re.e.rch Université catholique de LouvainB-1348 Louvain-la-NeuveBelgium

Groundwate. flows play a ke. role.in the.re.harge.of aquife.s, the.transport of solute. through subsurface.syste.0} or the.control of surface.runoff. Pre.icting the.e.proce.se. re.uire. the.use.of groundwate. m.de.s with the.r applicability dire.tly linke. to the.r accuracy and com.utational e.ficie.cy. In this pape., we.pre.e.t a ne. m.thod to m.de. wate. dynam.cs in variably- saturate. porous m.dia. Our m.de. is base. on a fully-e.plicit discontinuous-Gale.kin form.lation of the.3D Richards e.uation, which shows a pe.fe.t scaling on paralle. archite.ture.. We.m.ke.use.of an adapte. jum. pe.alty te.m.for the.discontinuous-Gale.kin sche.0} and of a slope.lim.te. algorithm.to produce.oscillation-fre. e.actly conse.vative.solutions. We.show that such an approach is particularly we.l suite. to infiltration fronts. The.m.de. re.ults are.in good agre.m.nt with the.re.e.e.ce.m.de. Hydrus-lD and se.m.prom.sing for large.scale.applications involving a coarse.re.re.e.tation of saturate. soil.

关键词： 3D subsurface.flow m.de. discontinuous Gale.kin m.thod slope.lim.te.s e.plicit tim. inte.ration