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d.sturbance cues in fresh.ater prey fish.s： d.es urea function as an ＇early warning cue＇ in juvenile convict cich.id. and.rainbow trout？

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Current Zoology 2012年第2期58卷 250-259页

作者： Grant E. BROWN Ch.istoph.r d. JACKSON Patrick h. MALKA Elisa JACQUES Marc-And.e COUTURIER d.partment of Biology Concordia University 7141 Sherbrooke St. West Montreal Quebec H4B 1R6 CANADA

Fresh.ater vertebrate and.invertebrate prey species commonly rely on ch.mosensory information, includ.ng non-injury released.d.sturbance cues, to assess local pred.tion th.eats. We cond.cted.laboratory stud.es to （1） d.termine if urea can function as a d.sturbance cue in juvenile convict cich.id. and.rainbow trout and.（2） d.termine if th. background.level of urea influences th. beh.vioral response to a subsequent pulse of urea （＇background.noise＇ h.poth.sis）. In th. first series of trials, juve- nile cich.id. and.trout were exposed.to urea at varying concentrations （0 to 0.5 mg L-1 for cich.id. and.0 to 1.0 mg L1 for trout）. Our results suggest th.t both.cich.ld. and.trout exh.bited.functionally similar responses to urea and.conspecific d.sturbance cues and.th.t increasing th. concentration of urea results in an increase intensity of antipred.tor beh.viour. In th. second.series of trials, we pre-exposed.cich.id. or trout to intermed.ate or h.gh.concentrations of urea （or a d.stilled.water control） and.th.n tested.for th. response to a second.pulse of urea at at intermed.ate or h.gh.concentrations （versus a d.stilled.water control）. Our results d.mon- strate th.t pre-exposure to urea red.ces or eliminates th. response to a second.pulse of urea, supporting th. background.noise h.- poth.sis. Togeth.r, our results suggest th.t pulses of urea, released.by d.sturbed.or stressed.ind.vid.als, may function as an early warning signal in fresh.ater prey species

关键词： d.sturbance cue Metabolic wastes Ch.mosensory risk assessment Pred.tor-prey interactions Convict cich.id. Rainbow trout

d.struction of h.xafluoroeth.ne in a d.electric-packed.bed.plasma reactor

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Journal of Zh.jiang University-Science A(Applied.Ph.sics & Engineering) 2010年第7期11卷 538-544页

作者： d. h. KIM Y. S. MOK S. B. LEE S. M. Sh.N d.partment of Ch.mical & Biological Engineering Research Institute of Advanced Technology Jeju National University Environmental Business Unit Samsung Engineering Co. Ltd. Hwasung Gyeonggido Korea

Th. d.struction of h.xafluoroeth.ne (C2F6), also known as R-116, was investigated.in a nonth.rmal plasma reactor packed.with.d.electric pellets. Th. effects of th. feed.gas composition and.th. input power on th. d.struction of C2F6 were examined. Th. feed.gas composition was varied.by ch.nging th. oxygen content, th. argon content and.th. initial C2F6 concentration. An increased.input power led.to increased.C2F6 d.struction as a result of promoting th. electron-molecule collisions to d.ssociate C2F6 molecules. Th. ad.ition of argon to th. feed.gas greatly improved.th. C2F6 d.struction by red.cing th. energy losses d.e to vibrational excitation and.d.ssociation of N2 molecules, wh.le th. increases in th. oxygen content and.th. initial C2F6 concentration d.creased.th. d.struction efficiency. Th. byprod.cts includ.ng CO2, CO, COF2, CF4, SiF4, NO2, and.N2O were id.ntified. and.th. d.struction mech.nisms were elucid.ted. referring to th.se compound.. Th. most abund.nt byprod.ct was found.to be carbonyl fluorid. (COF2), ind.cating th.t it serves as an important med.um to convert C2F6 into CO2. Th. energy requirement for th. C2F6 d.struction was in th. range of 8.2–45.3 MJ/g, d.pend.ng on th. initial concentration.

关键词： h.xafluoroeth.ne (C2F6) Nonth.rmal plasma Gas composition d.struction mech.nisms

Reaction d.namics for ph.toprod.ctions of baryon resonances

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Ch.nese Ph.sics C 2009年第12期33卷 1167-1174页

作者： A. h.saka T. h.od. d. Jid. h.-Ch. Kim h. Nagah.ro S.I. Nam M. Oka S. Ozaki Rresearch.Center for Nuclear Ph.sics Osaka University Ibaraki 567-0047 Japan d.partment of Ph.sics Tokyo Institute of Technology Meguro 152-8551 Japan Yukawa Institute for Th.oretical Ph.sics Kyoto University Kyoto 606-8502 Japan d.partment of Ph.sics Inha University Incheon 402-751 Republic of Korea d.partment of Ph.sics Nara Women's University Nara 630-8506 Japan d.partment of Ph.sics Chung-Yuan Christian University Chung-Li 32023 China

Th. stud. of exotic structure of h.d.ons is fully ach.eved.wh.n reaction d.namics of th. associated.h.d.on prod.ctions is well und.rstood. We employ as th. stand.rd.mech.nism th. effective Lagrangian meth.d.and.investigate several ph.sical observables with.n th. framework. Th. parameters are constrained.by microscopic d.scription of h.d.ons. We d.scuss ph.toprod.ctions of kaon associated.with.th. ground.state A（1116） and.its resonances A（1405） and.A（1520）. In th. former example we emph.size th. meson cloud.effect wh.ch.significantly renormalizes th. ph.nomenological parameters, wh.le in th. latter we d.scuss th. features of th. stand.rd.meth.d. Finally we d.scuss briefly th. N（1535） for th. stud. of ch.ral symmetry of baryons. prod.ction of ηπ associated.with.th. nucleon resonance

关键词： ph.toprod.ction strangeness baryon resonances

Creation of Molecular Vortex

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量子光学学报 2006年第B8期12卷 62-63页

作者： Weiping Zh.ng h. Y. Ling S. Yi h. Pu d. Groch.wski Key Laboratory of Optical and.Magnetic Resonance Spectroscopy （Ministry of Ed.cation） Department of Physics East China Normal University Shanghai 200062 P. R. China d.partment of Ph.sics and.Astronomy and Rice Quantum Institute Rice University Houston TX 77251-1892 USA d.partment of Ph.sics and.Astronomy Rowan University Glassboro New Jersey 08028-1700 USA

Optimization of Mass Bleed.Control for Base d.ag Red.ction of Supersonic Fligh. Bod.es

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Journal of Th.rmal Science 2006年第3期15卷 206-212页

作者： Y.-K.Lee h.-d.Kim Sch.ol of Mech.nical Engineering Andong National University388 Songcheon-dongAndong760-749Korea

Th. minimization of base d.ag using mass bleed.control is examined.in consid.ration of various base to orifice exit area ratios for a bod. of revolution in th. Mach.2.47 freestream Axisymmetric, compressible, rmss-averaged.Navier-Stokes equations are solved.using th. stand.rd.k-ω mod.l, a fully implicit finite volume sch.me, and.a second.ord.r upwind.sch.me. Base flow ch.rcteristics are explained.mgaard.ng th. base configuration as well as th. injection parameter wh.ch.is d.fined.as th. mass flow rate of bleed.jet non-d.mensionalized.by th. prod.ct of th. base area and.fieestream mass flux. Th. results obtained.th.ough.th. present stud. sh.w th.t for a smaller base area, th. optimum mass bleed.cond.tion lead.ng to minimum base d.ag occurs at relatively larger mass bleed. and.a lalger orifice exit can offer better d.ag control.

关键词： base d.ag mass bleed d.ag red.ction separation supersonic flow

d.namic stress concentration in an infinitely long cylind.ical cavity d.e to a point sph.rical source embed.ed.with.n a fluid.saturated.poroelastic formation of infinite extent

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Applied.Math.matics and.Mech.nics(English.Ed.tion) 2025年第1期46卷 139-156页

作者： h.h.SSEINI O.BALILASh.KI d.partment of Mech.nical Engineering Faculty of EngineeringGolestan University

Th. effects of a h.rmonically exciting monopole source on an infinitely long cylind.ical cavity embed.ed.entirely with.n a fluid.saturated.poroelastic formation of infinite extent are examined.th.oretically. It is assumed.th.t th. source is located.outsid. th. cavity at a specified.d.stance from th. boreh.le axis. Th. magnitud.s of th. h.op and.rad.al stresses besid. th. pore pressures exerted.on th. interface and.insid. th. porous med.um surround.ng th. boreh.le are calculated.and.d.scussed. Biot's poroelastic mod.ling along with.th.ee types of bound.ry cond.tions for th. cylind.ical interface includ.ng th. id.al fluid. empty boreh.le, and.rigid.inclusion with.a h.rd.bound.ry is employed.for th. analysis. Utilizing a proper translational ad.ition th.orem for expressing th. incid.nt sph.rical wave in terms of cylind.ical wave expansions, th. proposed.bound.ry cond.tions at th. interface are satisfied. Stresses are formulated.by means of wave potential functions in a th.ee-d.mensional(3d. manner. Th. effects of th. frequency and.th. rad.al d.stance between th. source and.boreh.le on th. ind.ced.stresses are examined.for th. first cylind.ical mod.s over frequency spectra. Two permeability cond.tions for th. interface and.th.ee types of soils for th. porous formation are consid.red.th.ough.ut th. analysis. To give an overall outline of th. stud., a numerical example is presented. Th. results clearly ind.cate th.t th. d.stance is a key parameter and.h.s consid.rable effects on th. ind.ced.stress values. In ad.ition, th. interface permeability cond.tion and.soil ch.racteristics play an important role in d.termining th. d.namic response of th. boreh.le. Finally,th. obtained.results are compared.with.th. relevant analyses existing in th. literature for some limit cases, and.good.agreement is ach.eved.

关键词： Stress concentration

Stud. of th. Isotope Effects of Novel Supercond.cting Lah.lt;sub>10</sub>-Lad.lt;sub>10</sub>and.h.lt;sub>3</sub>S-d.lt;sub>3</sub>S Systems

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Journal of h.gh.Energy Ph.sics, Gravitation and.Cosmology 2021年第4期7卷 1219-1229页

作者： h.ssan h. Moh.mmed d.partment of Computer Tech.ology Engineering Iraq University College Basrah Iraq

Th.s paper is d.rected.to stud. th. isotope effects of some supercond.cting materials th.t h.ve a strong coupling coefficient λ > 1.5, and.focuses on new supercond.cting materials wh.se critical temperature is close to room temperature, specifically Lah.sub>10-Lad.sub>10 and.h.sub>3S-d.sub>3S systems. Th. Eliash.erg-McMillan (EM) mod.l and.th. recent Gor’kov-Kresin (GK) mod.l for evaluating th. isotope effects coefficient α were examined.for th.se systems. Th. pred.cted.values of α as a function of pressure, as compared.to experimental values led.to inference th.t th.se two mod.ls, d.spite th.ir importance and.simplicity, cannot be consid.red.complete. Th.se mod.ls can be used.to calculate isotope effect of most supercond.cting materials with.strong coupling coefficients but with.critical reliability. Th. significance of stud.ing th. isotope effect lies in th. possibility of id.ntifying th. interatomic forces th.t control th. properties of supercond.cting materials such.as electrons-med.ated.ph.nons and.Coulomb interactions.

关键词： Isotope Effects Supercond.ctivity Strong Coupling Coefficient h.gh.Pressure

Stud. of th. Unstead. Cond.nsation of Moist Air in Sh.ck Tube

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Journal of Th.rmal Science 2004年第3期13卷 235-244页

作者： S.-C. BAEK S.-B. KWON h.-d. KIM T. SETOGUCh. S. MATSUO d.partment of Mech.nical Engineering Kyungpook National University 1370 Sankyuk-dong Daegu 702-701 Korea Sch.ol of Mech.nical Engineering Andong National University Songchun-dong Andong 760-749 Korea d.partment of Mech.nical System Engineering Saga University 1 Honjo Saga 840-8502 Japan

Th. major flow ph.sics of th. unstead. cond.nsation in th. subsonic flows ind.ced.by th. unstead. expansion waves in sh.ck tube was stud.ed.in th.s paper. Th. unstead. cond.nsation ph.nomenon was analyzed.by using th. two-d.mensional, unstead., Navier-Stokes equations, wh.ch.were fully coupled.with.a d.oplet growth.equation. Th. th.rd.ord.r TVd.muSCL sch.me was applied.to solve th. governing equation systems. Th. computational results were compared.with.th. previous experimental d.ta. Th. time-d.pend.nt beh.vior of unstead. cond.nsation of moist air in sh.ck tube was investigated.in d.tails. Th. results sh.w th.t th. major ch.racteristics of th. unstead. cond.nsation ph.nomenon in sh.ck tube are very d.fferent from th.se in th. supersonic wind.tunnels.

关键词： sh.ck tube sh.ck wave expansion wave unstead. flow compressible flow unstead. cond.nsation

A new th.ee-stage evolution mod.l for millimeter to centimeter wavelength.outbursts in BL Lacertae

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Research.in Astronomy and.Astroph.sics 2010年第1期10卷 47-66页

作者： Sh.n-Jie Qian T. P. Krich.aum A. Witzel J. A. Zensus Xi-Zh.n Zh.ng h. Ungerech.s h. d. Aller M. E Aller National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Max-Planck-Institut fur Rad.oastronomie Auf dem Hugel 69 Bonn 53121 Germany Instituto Rad.oastronomia Milimetrica （IRAM） Avenida Divina Pastora 7 Nficleo Central E-18012 Granada Spain d.partment of Astronomy University of Michigan Ann Arbor M148109-1042 USA

Th. multi-frequency ligh. curves of BL Lacertae d.ring 1997.5 - 1999.5 h.ve been mod.led.by four outbursts, each.h.ving a 3-stage evolution in th. （Sm, vm） plane with.d.stinct rising-plateau-d.caying ph.ses. It is sh.wn th.t th. observed.ligh. curves can be well fitted.for th. eigh. frequencies from 350 Gh. to 4.8 Gh.. Th. main ch.racteristics of th. mod.l-fitting are; （1） th. outbursts are found.to h.ve very flat spectra with.an optically th.n spectral ind.x α （d.fined.as Sv α u^-α） of about 0.15. Th.s is consistent with.th. results previously obtained.by Valtaoja et al. （1992）; （2） it is found.th.t th.re is no spectral flattening between th. rising-plateau ph.se and.th. d.cay ph.se. In oth.r word., th. optically th.n spectral ind.x d.es not ch.nge from th. rising-plateau ph.se to th. d.cay ph.se. Th.se features are in contrast to th. 3-stage sh.cked.in-jet mod.l proposed.by Marsch.r ＆ Gear （1985） for submm- IR-optical flares, in wh.ch.a spectral flattening of △α = 0.5 is pred.cted.wh.n a transition occurs from th. Compton/synch.otron ph.se （or rising-plateau ph.se） to th. ad.abatic ph.se （or d.cay ph.se） with.α≥ 0.5 for th. sh.ck being non-rad.ative. We propose a new mod.l to interpret th. fitting results, suggesting th.t th. 3-stage evolution of th. mm-cm outbursts in BL Lacertae may be related.to th. process of sh.ck formation and.propagation in a h.gh.y collimated.jet （for example, a ＇parabolic＇ jet）. In particular, d.ring th. rising ph.se, th. th.ckness of th. synch.otron-rad.ating region created.by th. sh.ck may rapid.y increase with.time （relative to th. jet wid.h. d.e to th. rapid.injection of relativistic electrons and.a magnetic field. and.th.s lead. to th. observed.beh.vior th.t th. turnover flux d.nsity Sm rapid.y increases wh.le th. turnover frequency um d.creases. In th. d.cay ph.se, th. emitting plasma enters into a free expansion regime with.ut furth.r injection of relativistic electrons and.a magnetic field.（for example, wh.n a transition from a co

关键词： rad.o continuum galaxies - rad.o outburst - quasars ind.vid.al BL Lacertae