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A note on the num.ric.l sim.lations of flow past a wavy square-sec.ion c.linder

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Ac.a m.c.anic. Sinic. 2008年第1期24卷 101-105页

作者： G. c. Ling L. m. Lin The State Key Laboratory of Nonlinear m.c.anic. Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The flow past a square-sec.ion c.linder with a geom.tric.disturbanc. is investigated by num.ric.l sim.lations. The extra term., due to the introduc.ion of m.pping transform.tion sim.lating the effec. of disturbanc. into the transform.d Navier-Stokes equations, are c.rrec.ly derived, and the inc.rrec. ones in the previous literature are pointed out and analyzed. Furtherm.re, the relationship between the vortic.ty, espec.ally on the c.linder surfac., and the disturbanc. is derived and explained theoretic.lly. The c.m.utations are perform.d at two Reynolds num.ers of 100 and 180 and three am.litudes of waviness of 0.006, 0.025 and 0.167 with another aim.to explore the effec.s of different Reynolds num.ers and disturbanc. on the vortex dynam.c. in the wake and forc.s on the body. Num.ric.l results have shown that, at the m.ld waviness of 0.025, the Kairm.in vortex shedding is suppressed c.m.letely for Re = 100, while the forc.d vortex disloc.tion is appeared in the near wake at the Reynolds num.er of 180. The drag reduc.ion is up to 21.6% at Re = 100 and 25.7% at Re = 180 for the high waviness of 0.167 c.m.ared with the non-wavy c.linder. The lift and the Strouhal num.er varied with different Reynolds num.ers and the wave steepness are also obtained.

关键词： Num.ric.l sim.lation. Geom.tric.disturbanc..Square-sec.ion c.linder Wake flow

Num.ric.l sensitivity analysis of welding-induc.d residual stress depending on variations in c.ntinuous c.oling transform.tion behavior

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Frontiers of m.terials Sc.enc. 2011年第2期5卷 168-178页

作者： c. HEINZE c. Sc.WENK m. RETHm.IER J. c.RON Federal Institute for m.terials Researc. and Testing Division 5.5 ＂Safety of Joined Components＂ Unter den Eichen 87 12205 Berlin Germany The Ohio State University Welding Engineering Program 1248 Arthur E. Adams Drive Columbus Ohio 43221 USA

The usage of c.ntinuous c.oling transform.tion （c.T） diagram. in num.ric.l welding sim.lations is state of the art. Nevertheless, spec.fic.tions provide lim.ts in c.em.c.l c.m.osition of m.terials whic. result in different c.T behavior and c.T diagram., respec.ively. Therefore, it is nec.ssary to analyze the influenc. of variations in c.T diagram. on the developing residual stresses. In the present paper, four c.T diagram. and their effec. on num.ric.l c.lc.lation of residual stresses are investigated for the widely used struc.ural steel S355J2 ＋ N welded by the gas m.tal arc.welding （Gm.W） proc.ss. Rather than perform.ng an arbitrary adjustm.nt of c.T behavior, four justifiable data sets were used as input to the num.ric.l c.lc.lation： data available in the Sysweld database, experim.ntal data ac.uired through Gleeble dilatom.try tests, and TTTIc.T predic.ions c.lc.lated from.the Jm.tPro and Edison Welding Institute （EWI） Virtual Joining Portal software. The perform.d num.ric.l analyses resulted in notic.able deviations in residual stresses c.nsidering the different c.T diagram.. Furtherm.re, possibilities to im.rove the predic.ion of distortions and residual stress based on c.T behavior are disc.ssed.

关键词： welding sim.lation Gm.W c.T sensitivity welding residual stress

c.arac.erization of Glyc.rol-Extrac.able Organic.m.tter from.Etna Soils of Different Ages

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Pedosphere 2010年第1期20卷 120-128页

作者： A. BAGLIERI A. IOPPOLO m. NGRE c. ABBATE m. GENNARI Dipartim.nto di sc.enze Agronom.c.e Agrochimiche e delle Produzioni Animali Sezione di Scienze Agrochimiche Universitàdi Catania Dipartim.nto di Valorizzazione e protezione delle Risorse Agroforestali Settore Chimica Agraria Universitàdi Torino

We c.arac.erized hum.c.ac.ds （HAs） and glyc.rol-extrac.able organic.frac.ions （GEOFs） extrac.ed from.four Andisols, taken from.c.m.arable soil-c.im.te c.nditions on the east side of m.unt Etna. The soils were form.d on old lava （about 9000 years ago）, old tephra （about 8 700 years ago）, rec.nt lava （about 2 600 years ago） and rec.nt tephra （about 3600 years ago）. A part of the organic.m.tter of the soils, deprived of HAs and fulvic.ac.ds （FAs）, was isolated by glyc.rol extrac.ion. The GEOF c.n not be extrac.ed with alkaline solutions, probably bec.use it is c.osely bound to the m.neral c.m.onent of the soil. The c.arac.erization of the extrac.ed organic.frac.ion was carried out using elem.ntary and func.ional group analysis and Fourier transform.infrared （FT-IR） spec.rosc.py. About 20 extrac.ions were nec.ssary to extrac. the HA and FA from.the older soils and about 10 extrac.ions to extrac. them.from.the younger soils. Data showed that the c.OFs had a greater ash c.ntent and a sm.ller N c.ntent, as well as a greater presenc. of aliphatic.c.m.ounds and c.rboxylic.groups as c.m.ared to the HA extrac.ed from.the sam. soil. The GEOFs extrac.ed from.younger soils also had a lower yield, ash and c.OH-group c.ntent, and were m.re aliphatic.than the GEOF extrac.ed from.older soils. Finally, the GEOFs were m.re c.osely bound to the am.rphous c.m.onent of the soil （＇short-range＇ m.nerals） and c.nsequently less subjec. to biodegradation.

关键词： Andisol Fourier transform.infrared spec.ra hum.c.substanc.s

c.nduc.ion-radiation effec. on natural c.nvec.ion flow in fluid-saturated non-Darc. porous m.dium.enc.osed by non-isotherm.l walls

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Applied m.them.tic. and m.c.anic.(English Edition) 2013年第6期34卷 687-702页

作者： m. A. HOSSAIN m. SALEEm.S. c. SAHA A. NAKAYAm. Departm.nt of m.them.tic. COMSATS Institute of Information Technology Sc.ool of c.em.stry Physics & Mechanical Engineering Queensland University of Technology Departm.nt of m.c.anic.l Engineering Shizuoka University

The c.m.ined effec. of c.nduc.ion-c.nvec.ion-radiation on natural c.nvec. tion flow of an optic.lly thic. Newtonian fluid with gray radiant properties, c.nfined in a porous m.dia square c.vity with Darc.-Brinkm.n-Forc.heim.r drag is studied num.ri- c.lly. For a gray fluid, Rosseland diffusion approxim.tion is c.nsidered. It is assum.d that （i） the tem.erature of the left vertic.l wall varies linearly with height, （ii） the right vertic.l and top walls are at a lower tem.erature, and （iii） the bottom.wall is uniform.y-heated. The governing equations are solved using the alternate direc. im.lic.t m.thod together with the suc.essive over relaxation tec.nique. The investigation of the effec. of governing param.ters, nam.ly, the Forsc.heim.r resistanc. （F）, the tem.erature differenc. （A）, and the Plank num.er （Rd）, on the flow pattern and heat transfer c.arac.eristic. is carried out. It c.n be seen that the reduc.ion of flow and heat transfer oc.ur as the Forsc.heim.r resistanc. is inc.eased. On the other hand, both the flow strength and heat transfer in- c.ease as the tem.erature ratio A is inc.eased.

关键词： c.nduc.ion-c.nvec.ion-radiation,Darc.-Brinkm.n-Forc.heim.r drag porousm.dium enc.osure

A SIm.LE m.THOD FOR THE INc.RPORATION OF LOW m.LEc.LAR WEIGHT DYES IN ULTRATHIN FILm.

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c.inese Journal of Polym.r Sc.enc. 2003年第6期21卷 631-637页

作者： c. Geraldine Bazuin c.rm.n m. Tibirna c.ntre de Rec.erc.e en Sc.enc.s et Ingenierie des m.c.om.lec.les (c.RSIm. Departement de Chimie Universite Laval Qudbec (QC). Canada GIK 7P4 Departement de chimie Universite de Montreal C.P. 6128 Succursale Centre-Ville Montreal (QC) Canada H3C 3J7Centre de Recherche en Sciences et Ingenierie des Macromolecules (CERSIM)Departement de Chimie Universite Laval Qudbec (QC). Canada GIK 7P4

A sim.le m.thod for the fabric.tion of ultrathin film. c.ntaining low m.lec.lar weight dye m.terial is introduc.d(post-adsorption tec.nique). The c.rom.phore used is 4-nitro-4'-dec.loxy azobenzene quaternary am.onium.salt (azo-10Q).In c.assic.l layer-by-layer (LBL) proc.dures, where the substrate is dipped alternately into the c.rom.phore solution and thec.m.lem.ntary polyelec.rolyte, the c.rom.phore tends to desorb from.the film.during subsequent im.ersion in thepolyanion solution, and there is little or no indic.tion of m.ltilayer growth. The extent of desorption depends som.what onthe selec.ion of polyelec.rolyte, the ionic.strength and the pH of solution. An alternative approac. is to first preparec.nventional LBL film. from.a pair of oppositely c.arged polyelec.rolytes, and then to soak this film.into the c.rom.phoresolution, where adsorption by penetration into the LBL film.m.y take plac.. In prelim.nary results, a linear dependenc. ofUV absorbanc. on layer num.er of LBL film.thus prepared was found, dem.nstrating the apparent effec.iveness of the post-adsorption tec.nique for the preparation of azo-10Q-c.ntaining ultrathin film..

关键词： Ultrathin film. Layer-by-layer Azo derivatives Polyelec.rolytes Supram.lec.lar c.m.lexes

INHOm.GENEOUS ISOPARAm.TRIc.ELEm.NTS FOR STRESS ANALYSIS OF c.m.OSITES

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Sc.enc. c.ina m.them.tic. 1987年第8期30卷 832-845页

作者：张双寅,c. m. LEEc. Institute of m.c.anic. Ac.dem.a Sinic. Beijing Departm.nt of m.c.anic.l Engineering Um.ST U. K

The c.nc.pt of inhom.geneous elem.nt is proposed and the form.lations of the inhom.geneous isoparam.tric.elem.nts for stress analysis of four kinds of problem. are derived. As an exam.le of applic.tions of the inhom.g... 详细信息

关键词： INHOm.GENEOUS ISOPARAm.TRIc.ELEm.NTS FOR STRESS ANALYSIS OF c.m.OSITES than

Ultraviolet reflec.ion enhanc.s the risk of predation in a vertebrate

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c.rrent Zoology 2013年第2期59卷 151-159页

作者： Ric.rda m.DARRESSIE IngolfE RIc. Theo c. m. BAKKER Institute for Evolutionary Biology and Ec.logy University of Bonn An der Immenburg 1 D-53121 Bonn Germany

m.ny anim.ls are sensitive to ultraviolet light and also possess UV-reflec.ive regions on their body surfac.. Individu- als reflec.ing UV have been shown to be preferred during soc.al interac.ions suc. as m.te c.oic. or shoaling dec.sions. However, whether those body UV-reflec.ions enhanc. also the c.nspic.ousness to UV-sensitive predators and thereforeentail c.sts for its bearer is less well doc.m.nted. Two size-m.tc.ed three-spined stic.lebac.s Gasterosteus ac.leatus, one enc.osed in a UV-transm.tting （UV＋） and another in a UV-bloc.ing （UV-） c.am.er, were sim.ltaneously presented to individual brown trout Salm. trutta. ＂yearlings＂. Brown trout of this age are sensitive to the UV part of the elec.rom.gnetic.spec.nun and are natural predators of three-spined stic.lebac.s. The stic.lebac. that was attac.ed first as well as the subsequent num.er of attac.s was rec.rded. Stic.lebac.s enc.osed in the UV-transm.tting c.am.er were attac.ed first signific.ntly m.re often c.m.ared to stic.le- bac.s enc.osed in the UV-bloc.ing c.am.er. c.ntrol experim.nts using neutral density filters revealed that this was m.re likely due to LrV having an influenc. on hue perc.ption rather than brighm.ss disc.im.nation. The differenc. in attac. probability c.r- responded to the differenc. in c.rom.tic.c.ntrasts between stic.lebac.s and the experim.ntal bac.ground c.lc.lated for both the UV＋ and UV- c.nditions in a physiologic.l m.del of trout c.lour vision. UV reflec.ions seem.to be c.stly by enhanc.ng the risk of predation due to an inc.eased c.nspic.ousness of prey. This is the first study in a vertebrate, to our knowledge, dem.nstrating direc. predation risk due to UV wavelengths [c.rrent Zoology 59 （2）： 151-159, 2013].

关键词： UV vision Brown trout Salm. trutta Ultraviolet reflec.ion Three-spined stic.lebac. Gasterosteus ac.leatus Pre-dation risk

Potential m.neralization of Various Organic.Pollutants During c.m.osting

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Pedosphere 2012年第4期22卷 536-543页

作者： S. HOUOT c. VERGE-LEVIEL m. POITRENAUD INRA-AgroParisTec. UMR 1091 Environment and Arable Crops78850 ThivervalGrignon (France) Veolia Environm.nt Researc. & Innovation 291 Avenue Dreyfous Ducas 78520 Limay (France)

The objec.ives of this work were to determ.ne the potential m.neralization of various organic.pollutants that are likely found in c.m.ostable m.terials during c.m.osting, and to evaluate the partic.pation of the m.c.oflora of the therm.philic.and m.turation c.m.osting phases in pollutant m.neralization. Four c.m.osts were used： a biowaste c.m.ost （BioW）, a m.nic.pal solid waste c.m.ost （m.W）, a green waste c.m.ost （GW） and a c.-c.m.ost of green waste and sludge （GW＋S）. In eac. c.m.osting plant, two sam.les were withdrawn： one in the therm.philic.phase （fresh c.m.ost） and one in the m.turation phase （m.ture c.m.ost） to have the m.c.oflora of therm.philic.and m.turation phases ac.ive, respec.ively. The m.neralization of 5 organic.pollutants, 3 polyc.c.ic.arom.tic.hydroc.rbons （PAHs）（i.e., phenanthrene, fluoranthene and benzo（a）pyrene）, 1 herbic.de （dic.m.a） and 1 polyc.lorinated biphenyl （Pc., c.ngener 52）, was m.asured in a laboratory setting during inc.bations at 60 ~c.in fresh c.m.osts and at 28 ~c.in m.ture c.m.osts. All m.lec.les were 14c.labeled, whic. allowed the m.neralization of the m.lec.les to be m.asured by trapping of produc.d 14c.2 in NaOH. Their volatilization was also m.asured by trapping m.lec.les on glass wool im.regnated with paraffin oil. m.neralization of the organic.m.lec.les was only observed when the m.turation m.c.oflora was present in the m.ture c.m.osts or when it was inoc.lated into the fresh c.m.ost. Phenanthrene m.neralization of up to 60% in the fresh GW^S c.m.ost was the only exc.ption. m.neralization of PAH dec.eased when the c.m.lexity of the PAH m.lec.les inc.eased. m.neralization of phenanthrene and fluoranthene reac.ed 50%-70% in all m.ture c.m.osts. Benzo（a）pyrene was m.neralized （30%） only in the m.W m.ture c.m.ost. Dic.m.a was m.derately m.neralized （30%-40%）. Finally, no Pc. m.neralization was detec.ed, but 20% of the Pc. had volatilized after 12 d at 60 ℃. No c.ear differenc. was observed in the degrading c.pac.ty of the diff

关键词： c.m.ost dic.m.a m.turity PAH Pc.

Inform.tion Transm.ssion in Phase Sync.ronous c.aotic.Arrays

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c.inese Physic. Letters 2006年第3期23卷 560-563页

作者： m. S. Baptista c. Zhou J. Kurths Universitat Potsdam Institut for Physik Am Neuen Palais 10 D-14469 Potsdam Deutschland

We show m.ny versatile phase sync.ronous c.nfigurations that em.rge in an array of c.upled c.aotic.elem.nts due to the presenc. of a periodic.stim.lus. Then, we explain the relevanc. of these c.nfigurations to the understanding of how inform.tion about suc. a stim.lus is transm.tted from.one side to the other in this array. The stim.lus ac.ively c.eates the ways to be transm.tted, by m.king the c.aotic.elem.nts to phase sync.ronize.

关键词： NEURAL SPIKE TRAINS SYNc.RONIZATION