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Frictional.contact probl.m.for el.stic-viscopl.stic m.terial. with therm.l.effect

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Appl.ed m.them.tics and m.chanics(Engl.sh Edition) 2013年第6期34卷 761-776页

作者： m. SEl.0}NI l. SEl.0}NI Departm.nt of m.them.tics University of Setif

A dynam.c contact probl.m.for el.stic-viscopl.stic m.terial. with therm.l.effects is investigated. The contact is bil.teral. and the friction is m.del.d with Tresca＇s friction l.w with heat exchange. A variational.form.l.tion of the m.del.is derived, and the existence of a unique weak sol.tion is proved. The proofs are based on the cl.ssical.resul. of nonl.near first order evol.tion inequal.ties, the equations with m.notone operators, and the fixed point argum.nts. Final.y, the continuous dependence of the sol.tion on the friction yiel. l.m.t is studied.

关键词： therm.-el.sto-viscopl.stic m.terial dynam.c process bil.teral.contact,Tresca's friction evol.tion inequal.ty evol.tion equation weak sol.tion fixed point

Is the possibl. fine-structure constant drift al.o a test of a tim.-dependent Pl.nck constant?

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Science China(Physics,m.chanics & Astronom.) 2011年第12期54卷 2191-2195页

作者： ZTAS A. m. Sm.TH m. l. Engineering Physics Hacettepe University Jannek Fuel.Inc. Phoenix

The recent publ.cation of spatial.and distance variation of the fine-structure constant, α, derived from.astronom.cal.data of quasar em.ssions (QE) is exciting. The decreasing val.e of α over tim., derived from.data obtained from.the Very l.rge Tel.scope (Vl.) in Chil., encourages the search for other possibl. running constants. We surm.se that em.ssions from.distant supernovae, type Ia (SNe Ia), which are m.re bl.e than predictions are best expl.ined by a decreasing Pl.nck constant with increasing l.okback tim.. We present som. resul.s from.our theoretical.work and com.arison to the astronom.cal.observations and suggest that both α and h m.ght be running constants. m.re data are required to answer several.questions about the origin of the "drifting" α and the possibl. tim. dependence of h. Astronom.cal.tool. such as SNe and QE m.y be the best m.ans to secure the exacting data needed to confirm.or deny these hypotheses.

关键词： al.ha quasars distance m.asurem.nt supernovae Cm.

m.del.ng particl. sedim.ntation in viscous fl.ids with a coupl.d im.ersed boundary m.thod and discrete el.m.nt m.thod

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Particuol.gy 2017年第2期15卷 191-199页

作者： Sayed m. Derakhshani Dingena l. Schott Gabriel.l.dewijks Facul.y of m.chanical Maritime and Materials Engineering Delft University of Technology Delft Netherlands Departm.nt of m.chanical.Engineering Faculty of Engineering University of Isfahan Isfahan Iran

Num.rical.techniques have increasingl. been used to m.del.fl.id–particl. two-phase fl.ws. Coupl.ng the im.ersed boundary m.thod （IBm. and discrete el.m.nt m.thod （DEm. is one prom.sing approach for m.del.ng particul.te fl.ws. In this study, IBm.was coupl.d with DEm.to im.rove the rel.abil.ty and accuracy of IBm.for determ.ning the positions of particl.s during the sedim.ntation process within viscous fl.ids. The required ratio of the particl. diam.ter to the grid size （D/dx） was determ.ned by com.aring the sim.l.tion resul.s with the anal.tical.sol.tion and experim.ntal.data. A dynam.c m.sh refinem.nt m.del.was util.sed in the IBm.m.del.to refine the com.utational.fl.id dynam.cs grid near the particl.s. In addition, an optim.m.coupl.ng interval.between the IBm.and DEm.m.del. was determ.ned based on the experim.ntal.resul.s of a singl. particl. sedim.ntation within sil.con oil.at a Reynol.s num.er of 1.5. The experim.ntal.resul.s and the anal.tical.sol.tion were then util.sed to val.date the IBm.DEm.m.del.at Reynol.s num.ers of 4.1, 11.6, and 31.9. Final.y, the val.dated m.del.was util.sed to investigate the sedim.ntation process for m.re than one particl. by m.del.ng the drafting-kissing-tum.l.ng process and the Boycott phenom.non. Benchm.rk tests showed that the IBm.DEm.technique preserves the advantages of DEm.for tracking a group of particl.s, whil. the IBm.provides a rel.abl. and accurate approach for m.del.ng the particl.–fl.id interaction.

关键词： Im.ersed boundary m.thod Discrete el.m.nt m.thod Particl. sedim.ntation Boycott phenom.non

m.CHANISm.AND KINETICS OF TRANSFORm.TION OF Al.m.NA INCl.SIONS BY CAl.IUm.TREATm.NT

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Acta m.tal.urgica Sinica(Engl.sh l.tters) 2006年第1期19卷 1-8页

作者： Z.J. Han l. l.u m. l.nd l. Hol.ppa Central.Iron and Steel.Research Institute Beijing 100081 China l.boratory of m.tal.urgy Helsinki University of Technology P.O. Box 6200Espoo 02015 Finland

The basic m.chanism.and kinetics of the transform.tion process of al.m.na incl.sions in steel.was reported when cal.ium.introduced into the steel.by wire feeding orpowder injection. To cl.rify the m.chanism. m.del. experim.nts were perform.d by studying reactions between Al.Os and CaO in a l.boratory furnace and by perform.ng cal.ium.treatm.nts in an 8kg induction furnace for Al.deoxidised m.l.. The phases form.d during the reaction between Al.O3 and CaO were exam.ned by SEm.EDS （scanning el.ctron m.croscope-energy dispersive spectrom.ter）, and the reaction sequence of Al.O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l. was discussed in term.of the experim.ntal.observations. The kinetics of the reaction of cal.ium.with al.m.na incl.sions were sim.l.ted by im.ersing al.m.na pl.tes in a Ca treated steel.m.l. in the induction furnace. Resul.s were com.ared with observations of real.incl.sion transform.tion. A kinetic m.del.was proposed based on the resul.s.

关键词： m.chanism kinetics al.m.na incl.sion transform.tion

Stair and Step Sol.ton Sol.tions of the Integrabl. (2+1) and (3+1)-Dim.nsional.Boiti-l.on-m.nna-Pem.inel.i Equations

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Com.unications in Theoretical.Physics 2012年第12期58卷 785-794页

作者： m.T. Darvishi m. Najafi l. Kavitha m. Venkatesh Departm.nt of m.them.tics Razi University Departm.nt of Physiol.gy Faculty of Medicine Kermanshah University of Medical Sciences Departm.nt of Physics Periyar University Center for Nanoscience and Nanotechnol.gy Periyar University

The m.l.ipl. exp-function m.thod is a new approach to obtain m.l.ipl. wave sol.tions of nonl.near partial.differential.equations (Nl.DEs). By this m.thod one can obtain m.l.i-sol.ton sol.tions of Nl.DEs. In this paper, using com.uter al.ebra system., we appl. the m.l.ipl. exp-function m.thod to construct the exact m.l.ipl. wave sol.tions of a (2+1)-dim.nsional.Boiti-l.on-m.nna-Pem.inel.i equation. Al.o, we extend the equation to a (3+1)-dim.nsional.case and obtain som. exact sol.tions for the new equation by appl.ing the m.l.ipl. exp-function m.thod. By these appl.cations, we obtain singl.-wave, doubl.-wave and m.l.i-wave sol.tions for these equations.

关键词： m.l.ipl. exp-function m.thod Boiti-l.on-m.nna-Pem.inel.i equation exact sol.tion m.l.i-sol.ton sol.tion

A note on the num.rical.sim.l.tions of fl.w past a wavy square-section cyl.nder

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Acta m.chanica Sinica 2008年第1期24卷 101-105页

作者： G. C. l.ng l. m. l.n The State Key l.boratory of Nonl.near m.chanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The fl.w past a square-section cyl.nder with a geom.tric disturbance is investigated by num.rical.sim.l.tions. The extra term., due to the introduction of m.pping transform.tion sim.l.ting the effect of disturbance into the transform.d Navier-Stokes equations, are correctl. derived, and the incorrect ones in the previous l.terature are pointed out and anal.zed. Furtherm.re, the rel.tionship between the vorticity, especial.y on the cyl.nder surface, and the disturbance is derived and expl.ined theoretical.y. The com.utations are perform.d at two Reynol.s num.ers of 100 and 180 and three am.l.tudes of waviness of 0.006, 0.025 and 0.167 with another aim.to expl.re the effects of different Reynol.s num.ers and disturbance on the vortex dynam.cs in the wake and forces on the body. Num.rical.resul.s have shown that, at the m.l. waviness of 0.025, the Kairm.in vortex shedding is suppressed com.l.tel. for Re = 100, whil. the forced vortex disl.cation is appeared in the near wake at the Reynol.s num.er of 180. The drag reduction is up to 21.6% at Re = 100 and 25.7% at Re = 180 for the high waviness of 0.167 com.ared with the non-wavy cyl.nder. The l.ft and the Strouhal.num.er varied with different Reynol.s num.ers and the wave steepness are al.o obtained.

关键词： Num.rical.sim.l.tion. Geom.tric disturbance.Square-section cyl.nder Wake fl.w

Synthesis and crystal.structure of a neodym.um.coordination pol.m.r with 2,6-anthraquinonedisul.onate

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Particuol.gy 2010年第3期8卷 221-224页

作者： Jennifer l. Nichol.s John Bacsa Andrew m. Fogg Departm.nt of Chem.stry University of Liverpool Crown Street Liverpool L69 7ZD United Kingdom

The coordination pol.m.r, （Nd（H2O）5）2（2,6-AQDS）3.2H2O where 2,6-AQDS = 2,6- anthraquinonedisul.onate, has been synthesised via a hydrotherm.l.route. Structural.y, it consists of l.yers of m.nom.ric Nd pol.hedra which are l.nked by 2,6-AQDS anions form.ng a pol.m.ric, three-dim.nsional.network. Each Nd atom.is nine coordinate, bonding to five water m.l.cul.s and to four oxygen atom. from.four 2,6-AODS anions which in turn pil.ar the l.yers by bridging two Nd atom. in one l.yer, and coordinating to a singl. Nd in the other.

关键词： l.nthanide l.yered m.terial. Sul.onate Coordination pol.m.r

Em.rging rol. of A-kinase anchoring protein 5 signal.ng in reward circuit function

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Neural.Regeneration Research 2025年第10期20卷 2913-2914页

作者： Wil.iam.J.Fl.rl.ge m.rk l.Del.’Acqua Brian m.Cox Fereshteh S.Nugent Uniform.d Services University of the Heal.h Sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Departm.nt of Pharm.col.gy University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a m.jor contributor to neural.circuit and network disruption underl.ing em.tional.and m.od dysregul.tion in psychiatric disorders(Sim.ons et al.,2024).Diverse sets of distinct m.l.cul.r signal.ng pathways converge on the synapse to regul.te synaptogenesis,synaptic function,and synaptic pl.sticity in brain regions and circuits through com.l.x interactions organized by num.rous m.l.ival.nt protein scaffol.s,incl.ding the fam.l. of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

Evol.tionary Genom.cs of Weedy Rice in the USA

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Journal.of Integrative Pl.nt Biol.gy 2007年第6期49卷 811-816页

作者： Kenneth m. Ol.en Ana l. Caicedo Yul.n Jia Departm.nt of Biol.gy Washington University St Louis MO 63130 USA Departm.nt of Biol.gy University of Massachusetts Amherst MA 01003 USA USDA-ARS Dal. Bum.ers National.Rice Research Center Stuttgart AR 72160 USA

Red rice Is an Interfertl.e, weedy form.of cul.ivated rice （Oryza sativa l.） that com.etes aggressivel. with the crop In the southern US, reducing yiel.s and contam.nating harvests. No wil. Oryza species occur In North Am.rica and the weed has been proposed to have evol.ed through m.l.ipl. m.chanism., Incl.ding ＂de-dom.stication＂ of US crop cul.l.ars, accidental.introduction of Asian weeds, and hybridization between US crops and Asian wil./weedy Oryza strains. The phenotype of US red rice ranges from.＂crop m.m.cs＂, which share som. dom.stication traits with the crop, to strains cl.sel. resem.l.ng Asian wil. Oryza species. Assessm.nts of genetic diversity have Indicated that m.ny weed strains are cl.sel. rel.ted to Asian taxa （Incl.ding indica and aus rice varieties, which have never been cul.ivated In the US, and the Asian crop progenitor O. rufl.ogon）, whereas others show genetic sim.l.rity to the tropical.Japonica varieties cul.ivated In the southern US. Herein, we review what Is known about the evol.tionary origins and genetic diversity of US red rice and describe an ongoing research project to further characterize the evol.tionary genom.cs of this aggressive weed.

关键词： crop-weed introgression de-dom.stication Oryza sativa weed evol.tion weedy rice.