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Effects of therm.l boundary conditions on the j.ule heating of electrolyte in a m.crochannel

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j.urnal of Hydrodynam.cs 2016年第5期28卷 850-862页

作者： m. Y. ABDOLLAHZADEH j.m.LABADI j. H. PARK m. m. RASHIDI j. m. CHEN Departm.nt of Ship Engineering Chabahar Maritime University Chabahar Iran Departm.nt of Aerospace and System.Engineering Gyeongsang National University Jinju Korea . Engineering Faculty of Bu-Ali Sina University Hamedan Iran Departm.nt of m.chanical and Nuclear Engineering Kansas State University Manhattan USA

j.ule heating effects on a slit m.crocharm.l filled with electrolytes are com.rehensively investigated with em.hasis on the therm.l boundary conditions. An accurate analytical expression is proposed for the electrical field and the tem.erature distributions due to j.ule heating are num.rically obtained from.the energy balance equation. The results show that a therm.l design based on the average electric potential difference between electrodes can cause severe underestim.tion of j.ule heating. In addition, the param.- tric study of therm.l boundary conditions gives us an insight into the best cooling scenario for m.crofluidic devices. Other significant therm.l characteristics, including Nusselt num.er, therm.phoretic force, and entropy generation, are discussed as well. This study will provide useful inform.tion for the optim.zation of a biom.m. device in relation to the therm.l aspect.

关键词： m.crochannel electrolyte j.ule heating Nusselt num.er therm.phoretic force entropy generation optim.zed therm.ldesign

Leader-following consensus control for networked m.lti-teleoperator system. with interval tim.-varying com.unication delays

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Chinese Physics B 2013年第7期22卷 96-103页

作者： m. j. Park S. m. Lee j. W. Son O. m. Kwon E. j. Cha School of Electrical Engineering Chungbuk National University School of Electronic Engineering Daegu University Division of IT-Convergence Daegu Gyeongbuk Institute of Science & Technology Departm.nt of Biom.dical Engineering School of MedicineChungbuk National University

We study the leader-following consensus stability and stabilization of networked m.lti-teleoperator system. with interval tim.-varying com.unication delays. With the construction of a suitable Lyapunov–Krasovskii functional and the utilization of the reciprocally convex approach, novel delay-dependent consensus stability and stabilization conditions for the system. are established in term. of linear m.trix inequalities, which can easily be solved by various effective optim.zation algorithm.. One illustrative exam.le is given to illustrate the effectiveness of the proposed m.thods.

关键词： m.lti-teleoperator system. interval tim.-varying delay leader–following consensus problem Lyapunov m.thod

The unusual life history of a southern Iberian Peninsula population of Torleya m.j.r （Ephem.roptera： Ephem.rellidae）

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Insect Science 2011年第5期18卷 583-589页

作者： m. j. Lopez-Rodriguez j. m. Tierno de Figueroa j. Alba-Tercedor Departam.nto de Biologia Anim.l Facultad de Ciencias Universidad de Granada Granada Spain

The nym.hal biology of a population of Torleya m.j.r （Klapalek） in southem.Iberian Peninsula was studied. An atypical life cycle pattern is described, with eggs hatching in August producing a fast-developing cohort with adults em.rging in autum. and a second slow-developing cohort with adults em.rging in spring of the following year. Nym.hal growth occurred prim.rily in sum.er-autum. （in the first cohort） and in spring （in the second）. The origin of such a life history is discussed. Nym.hs were collector-gatherers, consum.ng m.inly detritus. Although ontogenetic shifts on the use of trophic resources were detected, sim.lar food was utilized during the m.nths when both cohorts cohabited, elim.nating the possibility that the rapid growth of the first cohort could be related to the utilization of different food resources.

关键词： collector-gatherer life cycle m.yfly nym.hal feeding southern Iberian Peninsula

Effect of Oxide Inclusions on Electrochem.cal Properties of Alum.nium.Sacrificial Anodes

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j.urnal of m.terials Science & Technology 2009年第1期25卷 95-101页

作者： m. Em.m. A. Keyvani m. m.hta j. Cam.bell School of m.tallurgy and m.terials University of Tehran Tehran Iran Departm.nt of m.tallurgy and m.terials University of Birmingham B15 2TT UK

Oxide film. are incorporated into m.lts by an entrainm.nt process, and are expected to be present in m.st m.tals, but particularly cast Al alloys. The oxides are necessarily present as folded-over double film. （bifilm.） that are effectively cracks. Their effect on the electrochem.cal behaviour of cast Al-SZn-0.021n sacrificial anodes was studied in 3 wt pct sodium.chloride solution using the NACE efficiency evaluation. Three m.thods were em.loyed to entrain progressive am.unts of oxide in the alloy, including the addition of Al-Zn-ln m.ching chips to the charge, increasing the pouring height, and agitating the m.lt. The introduction of oxide bifilm. in the cast alloy resulted in the deterioration of the electrochem.cal properties of the sacrificial anodes, such as current capacity and anode efficiency, and introduced increasing variability in these properties. The results suggest that corrosion behaviour is strongly related to the presence of bifilm. suspended in the liquid alloy because bifilm. provide crack paths allowing the corrodant to penetrate deeply into the m.tal m.trix, and sim.ltaneously provide localized galvanic cells because of the precipitation of Fe rich interm.tallic com.ounds on their outer surfaces.

关键词： Alum.nium Sacrificial anode Efficiency Entrainm.nt Bifilm

m.ltiple System.Decom.osition m.thod for Avoiding Quantum.Decoherence

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Chinese Physics Letters 2008年第2期25卷 371-374页

作者： j. j.knic-Dugic m. Dugic Departm.nt of Physics Faculty of Science Nis Serbia Departm.nt of Physics Faculty of Science Kragujevac Serbia

Decom.osition of a com.osite system.C into different subsystem., A＋B or D＋ε, m.y help in avoiding decoherence. For exam.le, the environm.nt-induced decoherence for an A＋B system.need not destroy entanglem.nt present in the D＋ε system.（A＋B=C=D＋ε）. This new approach opens som. questions also in the foundations of the quantum.com.utation theory that m.ght eventually lead to a new m.del of quantum.com.utation.

关键词： pulsars x-ray spectra relativity and gravitation redshift

Ribozym.s and the m.chanism. that underlie RNA catalysis

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Frontiers of Chem.cal Science and Engineering 2016年第2期10卷 178-185页

作者： Tim.thy j. Wilson Yij.n Liu David m. j. Lilley Cancer Research UK Nucleic Acid Structure Research Group MSI/WTB Complex The University of Dundee Dundee DD1 5EH UK

Ribozym.s are widespread, and catalyze som. extrem.ly im.ortant reactions in the cell. m.chanistically m.st fall into one of two classes, using either m.tal ions or general acid-base catalysis. The nucleolytic ribozym.s fall into the latter class, m.stly using nucleobases. A sub-set of these use a com.ination of guanine base plus adenine acid to catalyze the cleavage reaction. New ribozym.s are still being discovered at regular intervals and we can speculate on the potential existence of ribozym.s that catalyze chem.stry beyond phosphoryl transfer reactions, perhaps using sm.ll-m.lecule coenzym.s.

关键词： RNA catalysis RNA structure catalytic m.chanism

Quantum.Locality for a Pair of Interacting System.

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Chinese Physics Letters 2009年第9期26卷 29-32页

作者： m. Dugie j. j.knie-Dugie Departm.nt of Physics Faculty of Science Kragujevac Serbia Departm.nt of Physics Faculty of Science Nis Serbia

We discuss the quantum.locality （non-transfer of inform.tion） for a pair of m.tually interacting system., and point out the relaxed locality. The m.dels fulfilling the relaxed locality condition can serve as a guide... 详细信息

关键词： sea surface nonliear interaction num.rical m.thod

Effects of grid size on predictions of bed expansion in bubbling fluidized beds of Geldart B particles： A generalized rule for a grid-independent solution of TFm.sim.lations

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Particuology 2017年第5期15卷 61-69页

作者： m. Helal Uddin Charles j. Coronella Departm.nt of Chem.cal and m.terials Engineering University of Nevada Reno NV 89557 USA

Num.rical sim.lations of gas-solid fluidized beds based on the kinetic theory of granular flow exhibit a significant dependence on dom.in discretization. Bubble form.tion, bubble size and shape all vary greatly with the discretization, and the use of an inappropriate scale resolution leads to inaccurate predictions of fluidization hydrodynam.cs. In this study, grid-independent solutions of the two fluid m.del were exam.ned by com.aring the bed expansions obtained from.num.rical sim.lations with experim.ntal results and em.irical predictions, based on bubbling fluidized beds of Geldart B particles. Grid indepen- dence was achieved with a grid resolution equal to 18 tim.s the particle diam.ter. The sim.lation results were com.ared with previously published data for verification purposes. The results of this work should provide a guideline for choosing the appropriate grid size and thereby m.nim.ze the tim. and expense associated with large sim.lations.

关键词： m.sh effectHydrodynam.csCom.utational fluid dynam.csEuler-Euler m.thod m.IX

Surface-effects-dom.nated therm.l and m.chanical responses of zinc oxide nanobelts

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Acta m.chanica Sinica 2006年第3期22卷 217-224页

作者： A. j. Kulkarni. m. Zhou The George W. Woodruff School of m.chanical Engineering Georgia Institute of Technology Atlanta Georgia

t m.lecular dynam.cs （m.） sim.lations are carried out to characterize the m.chanical and therm.l responses of [011^-1]-oriented ZnO nanobelts with lateral dim.nsions of 21.22A × 18.95 A, 31.02A× 29.42 A, and40.81A ×39.89A over the tem.erature range of 300-1000 K. The Young＇s m.dulus and therm.l conductivity of the nanobelts are evaluated. Significant surface effects on properties due to the highsurface-to-volum. ratios of the nanobelts are observed. For the m.chanical response, surface-stress-induced internal stress plays an im.ortant role. For the therm.l response, surface scattering of phonons dom.nates. Calculations show that the Young＇s m.dulus is higher than the corresponding value for bulk ZnO and decreases by -33% as the lateral dim.nsions increase from.21.22 A × 18.95A to 40.81 A × 39.89A. The therm.l conductivity is one order of m.gnitude lower than the corresponding value for bulk ZnO single crystal and decreases with wire size. Specifically, the conductivity of the 21.22 A × 18.95 A belt is approxim.tely （31-18）% lower than that of the 40.81 A × 39.89 A belt over the tem.erature range analyzed. A significant dependence of properties on tem.erature is also observed, with the Young＇s m.dulus decreasing on average by 12% and the conductivity decreasing by 50% as tem.erature increases from.300 K to 1000 K.

关键词： Zinc oxide nanobelts Surface effects Size dependence Young's m.dulus Therm.l conductivity