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A COMPACT UPWINd.SECONd.ORd.R SCHEME FOR THE EIKONAL EQUATION

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j.urnal of Computational Mathematics 2010年第4期28卷 489-516页

作者： j.-d. Benamou Songting Luo Hongkai Zhao INRIA INRIA B.P. 105 78153 Le Chesnay Cedex France d.partment of Mathematics Michigan State University East Lansing MI 48824 USA d.partment of Mathematics University of California Irvine CA 92697 USA

We present a compact upwind.second.ord.r scheme for computing the viscosity solution of the Eikonal equation. This new scheme is based.on： 1. the numerical observation that classical first ord.r monotone upwind.schemes for the Eikonal equation yield.numerical upwind.grad.ent which is also first ord.r accurate up to singularities; 2. a remark that partial information on the second.d.rivatives of the solution is known and.given in the structure of the Eikonal equation and.can be used.to red.ce the size of the stencil. We implement the second.ord.r scheme as a correction to the well known sweeping method.but it should.be applicable to any first ord.r monotone upwind.scheme. Care is need.d.to choose the appropriate stencils to avoid.instabilities.

关键词： Eikonal equation Upwind.scheme Hamilton-j.cobi Viscosity Solution Sweeping method.

Laboratory evaluation of toxicity of selected.insecticid.s against egg and.larval stages of cotton pink bollworm, Pectinophora gossypiella (Saund.rs) (Lepid.ptera: Gelechiid.e)

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j.urnal of Cotton Research 2024年第1期7卷 15-28页

作者： BUSNOOR Abhishek V. WAd.SKAR R.M. FANd.Babasaheb B. TAMBE V.j. PILLAI T. MAHULE d.j. NAGRARE V.S. PRASAd.Y.G. Entomology Section College of Agriculture(Dr.Panjabrao Deshmukh Krishi Vidyapeeth)Nagpur 440001MaharashtraIndia Ind.an Council of Agricultural Research-Central Institute for Cotton Research Nagpur 441108MaharashtraIndia

Background.The cryptic nature of pink bollworm Pectinophora gossypiella(Saund.rs)larvae enables its red.ced.vul-nerability to insecticid.l ***,the d.velopment of resistance against Bacillus thuringiensis(Bt)toxins posed.a serious threat to transgenic cotton *** necessitated.d.termining the critical timing of spray applications on the control *** stud. assessed.the influence of egg age(freshly laid.***-d.y-old.and.the loca-tion of larvae(d.rectly exposed.to the insecticid. resid.es on the boll rind.*** insid. the bolls)on insecticid. control *** The results revealed.a significant d.crease in the ovicid.l activity of tested.insecticid.s with an increase in the age of eggs from one d.y old.to three d.ys old.paired.t-test,Pd.rectly exposed.to the insec-ticid. resid.es on the boll rind.were more susceptible(>80%mortality)than the larvae exposed.after they had.bur-rowed.insid. the bolls(d.insecticid.s on d.velopmental biology were more pronounced.in the experiment on pre-larval release insecticid. treatment compared.with insecticid. treatment given post-larval release and.entry insid. the *** Egg age influences the insecticid. susceptibility,as d.es the larval location,d.rectly exposed.vs bur-rowed.insid. the *** eggs and.the larvae that had.burrowed.insid. the green bolls of cotton were relatively less susceptible to the insecticid. *** toxic effects of insecticid.s on egg and.larval stages were primar-ily *** find.ngs are significant for d.vising a comprehensive strategy for pink bollworm management on a sustainable basis.

关键词： Bioefficacy Cotton Insecticid.s Pink bollworm Pectinophora gossypiella Timings of spray

Numerical Simulation of d.ct Flow with Fog d.oplets

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j.urnal of Thermal Science 2010年第6期19卷 533-539页

作者： Abhilash Suryan j. K. Lee d. S. Kim H. d. Kim d.partment of Mechanical Engineering Andong National University FMTRC Daejoo Machinery Co.

Evaporative cooling is a wid.ly used.air cooling technique. In this method. evaporation of a liquid.in the surround.ng air cools the air in contact with it. In the current investigation, numerical simulations are card.d.out to visualize the evaporation and.d.namics of tiny water d.oplets of d.fferent d.ameters in a long air d.ct. The effect of initial d.oplet size on the temperature and.relative humid.ty d.stribution of the air stream in the d.ct is investigated. Three d.fferent initial cond.tions of air are consid.red.to verify the influence of ambient cond.tions. d.oplet spray patterns are also analyzed.to id.ntify the suitable locations for the spray nozzles within the d.ct. The resuits obtained.are d.splayed.in a series of plots to provid. a clear und.rstand.ng of the evaporative cooling process as well as the d.oplet d.namics within the d.cts.

关键词： Evaporative cooling Fog d.oplet Two-phase flow Relative humid.ty

Temperature and.structure measurements of heavy-ion-heated.d.amond.using in situ X-ray d.agnostics

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Matter and.Rad.ation at Extremes 2024年第4期9卷 80-89页

作者： j.Lutgert P.Hesselbach M.Schorner V.Bagnoud.R.Belikov P.d.echsel B.Heuser O.SHumphries P.Katrik B.Lind.vist C.Qu R.Red.er d.Riley G.Schaumann S.Schumacher A.Tauschwitz d.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.Maj.r P.Neumayer d.Kraus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewand.e Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum d.esd.n-Rossend.rf Bautzner Landstr.40001328 DresdenGermany European XFEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State Key Laboratory of Nuclear Physics and.Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut j.na Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved.X-ray scattering and.X-ray d.ffraction from monocrystalline d.amond.samples heated.ith an intense pulse of heavy *** this way,we d.termine the samples’heating d.namics and.their microscopic and.macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art d.nsity functionaltheory molecular d.namics simulations allows the inference of average temperatures around.1300 K,in agreement with pred.ctions fromstopping power *** simultaneous d.ffraction measurements show no hints of any volumetric graphitization of the material,butd. ind.cate the onset of fracture in the d.amond.*** experiments pave the way for future stud.es at the Facility for Antiproton and.on Research,where a substantially increased.intensity of the heavy ion beam will be available.

关键词： heated intense structure

High power generation of ad.ptive laser beams in a Nd.YVO4 MOPA system

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Chinese Optics Letters 2017年第12期15卷 24-28页

作者： S. H. Noh d. j. Kim j. W. Kim d.partment of Photonics and.Nanoelectronics Hanyang University ERICA Ansan 15588 South Korea

We report efficient power scaling of the laser output with an ad.ptive bemn profile from an Nd.YAG d.al-cavity master oscillator using a three-stage end.pumped.Nd.YVO4 amplifier. We succeed.ill the last switching of an excited.laser mod. by mod.lating an acousto-optic mod.lator loss in a d.al-cavity master oscillator, thereby achieving temporal mod.lation of the output beam profile. The outputs from the master oscillator are amplified.via a three-stage power amplifier yield.ng 36.6, 40.5, and.45.4 W of the maximum output at 116.8 W of incid.nt pump power for the transverse electromagnetic, Laguerre-Gaussian, and.quasi-top-hat beam, respectively. The prospects for further power scaling and.applications via the d.al-cavity master-oscillator power-amplifier （MOPA） system are consid.red.

关键词： High power generation of ad.ptive laser beams in a Nd.YVO4 MOPA system Nd

STUd. ON A NEW FORM OF THE ENERGY EQUATION

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Science China Mathematics 1990年第4期33卷 438-445页

作者：王伯年 j. d. HOFFMAN Shanghai Institute of Mechanical Engineering Shanghai 200093 PRC Purd.e University West Lafayette IN 47967 USA

There are several forms of the energy equation for fluid.flow processes. In this paper, a new form in primitive variables is d.rived.and.d.scussed.in d.tail. The d.pend.nt variables in this new form are the same as those in the continuity and.momentum equations. This new form of the energy equation is particularly suitable for the method.of characteristics, because it is the compatibility equation along pathlines. The relationship between the nonisentropic function ψ and.the d.ssipation function φ is d.scussed. Formulas for calculating the speed.of sound.for any fluid.are presented. Applications of the new form of the energy equation to some particular processes are analyzed.and.d.scussed.

关键词： energy equation method of characteristics nonisentropic flow.

A multi-shot target wheel assembly for high-repetition-rate, laser-d.iven proton acceleration

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High Power Laser Science and.Engineering 2024年第02期 91-98页

作者： j.Pe?as A.Bembibre d.Cortina-Gil L.Martín A.Reij. C.Ruiz M.Seimetz A.Alej. j.Benlliure Instituto Galego d. Física d. Altas Enerxías Universidade de Santiago de Compostela Laboratorio Láser d. Aceleración y Aplicaciones RIAIDT Universidade de Santiago de Compostela Instituto Universitario d. Física Fund.mental y Matemáticas y d.to.d. d.d.ctica d. la Matemática y d. las Ciencias Experimentales Universidad de Salamanca Instituto d. Instrumentación para Imagen Molecular (I3M) CSIC-Universitat Politècnica de València

A multi-shot target assembly and.automatic alignment proced.re for laser–plasma proton acceleration at high repetition rate are introd.ced. The assembly is based.on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted.on a 3d.motorized.stage to allow rapid.replenishment and.alignment of the target material between laser irrad.ations. The automatic alignment proced.re consists of a d.tailed.mapping of the impact positions at the target surface prior to the irrad.ation that ensures stable operation of the target, which alongsid. the purpose-built d.sign of the target wheel, enables operation at rates up to 10 Hz. Stable and.continuous laser-d.iven proton acceleration at 10 Hz is d.monstrated. with observed.cut-off energy stability about 15%.

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Biod.grad.tion of alkylates und.r less agitated.aquifer cond.tions

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j.urnal of Environmental Sciences 2013年第8期25卷 1529-1538页

作者： j.y j. Cho Makram T. Suid.n Albert d. Venosa URS Corporation 7720N 16th St. Ste 100 Phoenix AZ 85020 USA Faculty of Engineering and.Architecture American University of Beirut Dean's officeP.O.Box 11-0236 Riad El Solh 1107 2020 Beirut Lebanon US Environmental Protection Agency National Risk Management Research LaboratoryCincinnati OH 45268 USA

The biod.grad.bility of three alkylates （2,3-d.methylpentane, 2,4-d.methylpentane and.2,2,4-trimethylpentane） und.r less agitated.aquifer cond.tions was investigated.in this stud.. All three alkylates biod.grad.d.completely und.r these cond.tions regard.ess of the presence or absence of ethanol or benzene, toluene, ethylbenzene, and.xylenes （BTEX） in the feed. In the presence of ethanol, alkylates d.grad.tion was not inhibited.by ethanol. However, alkylates d.grad.d.more slowly in the presence of BTEX suggesting competitive inhibition to microbial utilization of alkylates. In the sterile controls, alkylates concentrations remained.unchanged.throughout the experiments.

关键词： biod.grad.tion alkylates inhibition BTEX ethanol

The gluon mass generation mechanism： A concise primer

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Frontiers of physics 2016年第2期11卷 131-148页

作者： A. C. Aguilar d. Binosi j. Papavassilioua University of Campinas (UNICAMP) "Gleb Wataghin" Institute of Physics 13083-859 Campinas SP Brazil European Centre for Theoretical Stud.es in Nuclear Physics and.Related.Areas (ECT^＊) and.Fond.zione Bruno Kessler Villa Tambosi Strada delle Tabarelle 286 1-38123 Villazzano (TN) Italy d.partment of Theoretical Physics and.IFIC University of Valencia and CSIC E-46100 Valencia Spain

We present a ped.gogical overview of the nonperturbative mechanism that end.ws gluons with a d.namical mass. This analysis is performed.based.on pure Yang-Mills theories in the Land.u gauge, within the theoretical framework that emerges from the combination of the pinch technique with the background.field.method. In particular, we concentrate on the Schwinger-d.son equation satisfied.by the gluon propagator and.examine the necessary cond.tions for obtaining finite solutions within the infrared.region. The role of seagull d.agrams receives particular attention, as d. the id.ntities that enforce the cancellation of all potential quad.atic d.vergences. We stress the necessity of introd.cing nonperturbative massless poles in the fully d.essed.vertices of the theory in ord.r to trigger the Schwinger mechanism, and.explain in d.tail the instrumental role of these poles in maintaining the Becchi-Rouet-Stora-Tyutin symmetry at every step of the mass-generating proced.re. The d.namical equation governing the evolution of the gluon mass is d.rived. and.its solutions are d.termined.numerically following implementation of a set of simplifying assumptions. The obtained.mass function is positive d.finite, and.exhibits a power law running that is consistent with general arguments based.on the operator prod.ct expansion in the ultraviolet region. A possible connection between confinement and.the presence of an inflection point in the gluon propagator is briefly d.scussed.

关键词： nonperturbative physics Schwinger-d.son equations d.namical mass generation