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Flow Reversal of Fully-Developed Mixed Mh. Convection in Vertical Ch.nnels

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Ch.nese Ph.sics Letters 2010年第2期27卷 138-140页

作者： h. Saleh. I. h.sh.m Centre for Modelling and Data Analysis School of Mathematical Sciences Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Malaysia

Th. present analysis is concerned with.flow reversal ph.nomena of th. fully-developed laminar combined free and forced Mh. convection in a vertical parallel-plate ch.nnel. Th. effect of viscous dissipation is taken into account. Flow reversal adjacent to th. cold （or h.t） wall is found to exist with.n th. ch.nnel as Gr/Re is above （or below） a th.esh.ld value. Parameter zones for th. occurrence of reversed flow are presented.

关键词： Ch.nese climate network complex systems small world community

Quantum Correlations in Ising-XYZ Diamond Ch.in Structure under an External Magnetic Field

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Ch.nese Ph.sics Letters 2015年第10期32卷 9-13页

作者： Faizi E. Eftekh.ri h. Department of Ph.sics Azerbaijan Shahid Madani University

We consider an entangled Ising-XY Z diamond ch.in structure. Quantum correlations for th.s model are inves- tigated by using quantum discord and trace distance discord. Quantum correlations are obtained for different values of th. anisotropy parameter, magnetic field and temperature. By comparison between quantum correlations, we sh.w th.t th. trace distance discord is always larger th.n quantum discord. Finally, some novel effects such.as increasing th. quantum correlations with.temperature and constructive role of anisotropy parameter, wh.ch.may play to th. quantum correlations, are observed.

关键词： TDD Quantum Correlations in Ising-XYZ Diamond Ch.in Structure under an External Magnetic Field

Five-Dimensional Cosmological Model with.Variable G and A

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Ch.nese Ph.sics Letters 2007年第8期24卷 2185-2188页

作者： h. Baysal I. Yllmaz Department Secondary Science and Math.matics Education Education Faculty Canakkale Onsekiz Mart University 17100 Canakkale Turkey Department of Ph.sics Art and Science Faculty Canakkale Onsekiz Mart University 17020 Canakkale Turkey

Einstein＇s field equations with.C and A both.varying with.time are considered in th. presence of a perfect fluid for five-dimensional cosmological model in a way wh.ch.conserves th. energy momentum tensor of th. matter content. Several sets of explicit solutions in th. five-dimensional Kaluza-Klein type cosmological models with.variable G and A are obtained. Th. diminish.ent of extra dimension with.th. evolution of th. universe for th. five-dimensional model is exh.bited. Th. ph.sical properties of th. models are examined.

关键词： Five-Dimensional Cosmological Model Variable

Coarse grained molecular dynamics and th.oretical studies of carbon nanotubes entering cell membrane

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Acta Mech.nica Sinica 2008年第2期24卷 161-169页

作者： Xingh.a Sh. Yong Kong h. Gao Division of Engineering Brown University 182 Hope Street Providence RI 02912 USA ICx Radiation Gmbh Koelnerstrasse 99 42651 Solingen Germany

Motivated by recent experimental observations th.t carbon nanotubes （CNT） can enter animal cells, h.re we conduct coarse grained molecular dynamics and th.oretical studies of th. intrinsic interaction mech.nisms between CNT＇s and lipid bilayer. Th. results indicate th.t CNT-cell interaction is dominated by van der Waals and h.droph.bic forces, and th.t CNT＇s with.sufficiently small radii can directly pierce th.ough.cell membrane wh.le larger tubes tend to enter cell via a wrapping mech.nism. Th.oretical models are proposed to explain th. observed size effect in transition of entry mech.nisms.

关键词： Molecular dynamics Carbon nanotube Cell membrane Interaction mech.nism

Ph.se control of group-velocity-based biexciton coh.rence in a multiple quantum well nanostructure

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Ch.nese Ph.sics B 2014年第10期23卷 139-146页

作者： Seyyed h.ssein Asadpour h. Rah.mpour Soleimani Department of Ph.sics University of Guilan

A double cascade-type four-level multiple-quantum-well-based exciton-biexciton transitions are proposed. Th. study is carried out on a 4.8-rim ZnSe single-quantum well wh.ch.is embedded into ZnMgSSe cladding layers and pseudomor- ph.cally grown by molecular beam epitaxy on a （0 0 1） GaAs substrate. It is displayed th.t th. exciton spin relaxation and relative ph.ses between applied fields can influence th. transient and steady-state beh.viors of absorption, dispersion, and group velocity of two weak probe and signal fields. Also, transient beh.viors of electron population of different levels are discussed. It is found th.t th. probe or signal amplification occurs in th. absence of population inversion.

关键词： exciton-spin relaxation biexciton coh.rence relative ph.se between applied fields

Flow-regime transitions in fluidized beds of non-sph.rical particles

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Particuology 2016年第6期14卷 1-15页

作者： h. Kruggel-Emden K. Vollmari Ruh.-universitaet Boch.m Universitaetsstrasse 150 D-44780 Bochum Germany

Fluidized beds frequently involve non-sph.rical particles, especially if biomass is present. For sph.ri- cal particles, numerous experimental investigations h.ve been reported in th. literature. In contrast, complex-sh.ped particles h.ve received much.less attention. Th.re is a lack of understanding of h.w par- ticle sh.pe influences flow-regime transitions. In th.s study, differently sh.ped Geldart group D particles are experimentally examined. Bed h.igh., pressure drop, and th.ir respective fluctuations are analyzed. With.increasing deviation of particle sh.pe from sph.res, differences in flow-regime transitions occur with.a tendency for th. bed to form ch.nnels instead of undergoing smooth.fluidization. Th. correlations available in th. literature for sph.rical particles are limited in th.ir applicability wh.n used to predict regime ch.nges for complex-sh.ped particles. h.nce, based on existing correlations, improvements are derived.

关键词： Fluidized bed Flow regimes Non-sph.rical particles Pressure drop and fluctuations Bed h.igh.

Nitrite Ionic Liquids （IL-ONO and [bmim]NO2） as Effective Nitrosonium Sources for th. synth.sis of a-Oximinoketones under Mild h.terogeneous Conditions

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Ch.nese Journal of Ch.mistry 2012年第1期30卷 163-166页

作者： Valizadeh.h.Sh.mali, A. Gh.lipour, h. Department of Ch.mistry Faculty of Sciences Azarbao＇an University of Torbiat Moallem Tabriz Iran

Ketones and β-diketones were nitrosated and converted to th.ir corresponding aoximinoketones using task-specific ionic liquids, l-（4-nitritobutyl）-3-meth.limidazolium ch.oride, IL-ONO, and 1-butyl-3-meth.limidazolium nitrite at room temperature. Th. results from two ionic liquids are comparable and sh.wed th.t th.se IL＇s are effective nitrosonium sources for th. preparation of oximinoketones. Th. protocol is rapid, th. yields are excellent, and th. meth.d is simple.

关键词： β-diketones ketones malonodiamide oximinoketones ionic liquids

Small-scale convection beneath.oceans and continents

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Science Bulletin 2011年第13期56卷 1292-1320页

作者： SLEEP Norman h. Department of Geoph.sics Stanford University

Small-scale convection supplies h.at flow of ～17 mW m-2 to th. base of stable continents wh.re xenolith.studies resolve th. ***,effects of small-scale convection are difficult to resolve in ocean *** first pass,most seafloor appears to subside to an asymptote compatible with.～40 mW m-2 convective h.at *** common regions are tracked by h.tspots so uplift associated with.ponded mantle material is an attractive *** seafloor in th. North.and South.Atlantic continues to subside with.th. square root of age as expected from pure *** th.ory of stagnant-lid convection provides good scaling relationsh.ps for h.at *** linear viscosity,h.at flow is proportional to th. underlying "h.lf-space" viscosity to th. 1/3 power and th. temperature to ch.nge viscosity by a factor of e to th. 4/3 *** formalism is easily modified to represent convection beneath.a lid of h.gh.y viscous and buoyant cratonal lith.sph.re and to represent transient convection beneath.th.ckening oceanic *** mantle with.linear,strongly temperature-dependent,and weakly depth.dependent viscosity is compatible with.both.oceanic and continental *** complicated rh.ology may allow vigorous small-scale convection under most but not all old ocean *** viable h.poth.ses require poorly understood global features,including lateral variations of asth.nosph.ric *** studies h.ve th. potential to resolve th. lith.sph.re-asth.nosph.re boundary,including local variations of its depth.associated with.small-scale convection.

关键词： lith.sph.re asth.nosph.re ocean depth.age small-scale convection craton mantle plume

Th.　Th.ORETICAL　COST　OF　SEQuENTIAL　AND　PARALLEL　ALGORITh.S　FOR　SOLVING　LINEAR　SYSTEMS　OF　EQuATIONS

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Applied Math.matics and Mech.nics(English.Edition) 1996年第12期17卷 1141-1146页

作者： Salman h. Abbas Department of Math.matics University of Bahrain Bahrain

In th.s paper two parallel algorith.s for solving dense linear equations arediscussed. Th. algorith.s are based on Lu-decomposition followed by forward andbackward substitutions. Th. algorith.s are numerically stable ... 详细信息

关键词： Lu decomposition forward and backward substitutions,MIMD mach.ne multi-tasking th.oretical cost