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Hydrodynam.cs of the interceptor on a 2-D flat plate by cFD and experim.nts

Journal of Hydrodynam.cs 2015年第6期27卷 919-933页

作者： m.NSOORI m. FERNANDES A.c. Departm.nt of Naval and Ocean Engineering Federal University of Rio de Janeiro

Nowadays, the use of interceptor by both partial and total dynam.c lift crafts is quite com.on. In this article, a lot of evidence is given regarding the effectiveness of interceptor. The interceptor, when placed at the stern region, changes the pressure distribution around the craft. Its presence affects drag force, lifting force and the position of pressure＇s center leading to a new trim. This study focuses on hydrodynam.c effects of interceptors on a 2-D fiat plate based on both com.utational fluid dynam.c （cFD） and experim.ntal approaches. The Reynolds average Navier-Stokes （RANS） equations are used to m.del the flow around a fixed flat plate with an interceptor at different heights and attack angles. Based on finite volum. m.thod and SIm.LE algorithm.which uses static structures, this m.del can be analyzed and the RANS results can be com.ared with the experim.ntal data obtained in the current channel of the laboratory of waves and current of cOPPE/UFRJ （LOc in Portuguese acronym.. According to the results, the increase of pressure at the end of the flat plate was proportional to the interceptor height. In addition, the existence of interceptors can significantly increase the lift force coefficient at high angles of attack also proportional to the interceptor height. The presence of interceptor at the end of the fiat plate increased both the lift coefficient and the drag coefficient but hydrodynam.c drag did not grow as fast as the lift coefficient did. The lift coefficient increased m.ch m.re. Furtherm.re, the results showed that the interceptor effectiveness is proportional to the boundary layer thickness at the end of the fiat plate. As the interceptor was inside the boundary layer alterations of flow speed led to changes in boundary layer thickness, directly affecting interceptor＇s efficiency. Optim.m.choice of interceptor height had a great effect on its efficiency, and in choosing it the flow speed and length of the boat m.st be taken into consideration.

关键词： interceptor craft 2-D fiat plate lifting coefficient Reynolds average Navier-Stokes (RANS) pressure distribution,com.utational fluid dynam.c drag

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UV reflectance but no evidence for colour m.m.cry in a putative brood-deceptive orchid corybas cheesem.nii

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current Zoology 2014年第1期60卷 104-113页

作者： m. m. KELLY A. c. GASKETT School of Biological Sciences The University of Auckland Private Bag 92019 Auckland 1142 New Zealand

Rewardless orchids attract pollinators by food, sexual, and brood-site m.m.cry, but other form. of sensory deception m.y also operate. Helm.t orchids （corybas, Nem.toceras and related genera） are often assum.d to be brood-site deceivers that m.m.c the colours and scents of m.shroom. to fool fem.le fungus gnats （m.cetophilidae） into attem.ting oviposition and polli- nating flowers. We sam.led spectral reflectances and volatile odours of an endem.c terrestrial New Zealand orchid corybas cheesem.nii, and co-occurring wild m.shroom.. The orchid is scentless to hum.ns and SPm. Gc-m. analyses did not detect any odours, but m.re sensitive m.thods m.y be required. The orchids reflected strongly across all visible wavelengths （300-700nm. with peaks in the UV （-320nm., yellow-green （500-600 nm. and red regions （650-700 nm., whereas m.shroom. and surrounding leaf litter reflected predom.nantly red and no UV. Rather than m.m.cking m.shroom., these orchids m.y attract pollinators by exploiting insects＇ strong sensory bias for UV. m.delling spectral reflectances into a categorical fly vision m.del and a generic tetrachrom.t vision m.del provided very different results, but neither suggest any m.m.cry of m.shroom.. However, these m.dels require further assessm.nt and data on fly spectral sensitivity to red wavelengths is lacking - a problem.given the predom.nance of red, fly-pollinated flowers worldwide

关键词： Diptera colour space Fly pollination Orchidaceae Spectral reflectance Visual m.delling

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Assessm.nt of Ecotoxicity of Topsoils from.a Wood Treatm.nt Site

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Pedosphere 2009年第2期19卷 143-155页

作者： m. m.NcH c.BES Um. BIOGEcO INRA 1202 Ecology of Communities University of Bordeaux 1 Bt B8 RdC Estgate 002Avenue des Facults F-33405 Talence (France) Um. BIOGEcO INRA 1202 Ecology of CommunitiesUniversity of Bordeaux 1Bt B8 RdC Estgate 002 Avenue des Facults F-33405 Talence (France)

A series of 9 soil sam.les were taken at a tim.er treatm.nt site in SW France where cu sulphate and chrom.ted copper arsenate （ccA） have been used as wood preservatives （Sites P1 to P9） and one soil sam.le was collected at an adjacent site on the sam. soil type （Site P10）. copper was a m.jor contam.nant in all topsoils, varying from.65 （Soil P5） to 2600 m. cu kg^-1 （Soil P7）, exceeding background values for French sandy soils. As and cr did not accum.late in soil, except at Site P8 （52 m. As kg^-1 and 87 m. cr kg^-1） where ccA-treated posts were stacked. Soil ecotoxicity was assessed with bioassays using radish, lettuce, slug Arion rufus L., and earthworm.Dendrobaena octaedra （Savigny）. There were significantly differences in lettuce germ.nation rate, lettuce leaf yield, radish root and leaf yields, slug herbivory, and earthworm.avoidance. An additional bioassay showed higher negative im.acts on bean shoot and root yields, Rhizobium.nodule counts on Bean roots, and guaiacol peroxidase activity in prim.ry Bean leaves for soil from.Site PT, with and without fertilisation, than for soil from.Site P10, despite both soils having a sim.lar value for com.uted free ion cu2＋ activity in the soil solution （pcu^2＋）. Beans grown in soil from.Site P7 that had been fertilised showed elevated foliar cu content and phytotoxic sym.tom.. Soils from.Sites P7 （treatm.nt plant） and P6 （storage of treated utility poles） had the highest ecotoxicity, whereas soil from.Site P10 （high organic m.tter content and cation exchange capacity） had the lowest. Except at Site P10, the soil factor pcu^2＋ com.uted with soil pH and total soil cu could be used to predict soil ecotoxicity.

关键词： contam.nated soil copper ecotoxicity test invertebrate plant.

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Hear no evil： The effect of auditory warning signals on avian innate avoidance, learned avoidance and m.m.ry

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current Zoology 2011年第2期57卷 197-207页

作者： Em.a c. SIDDALL Nicola m. m.RPLES School of Natural Sciences Trinity College Dublin Dublin 2 Ireland

m.ny aposem.tic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a m.ltim.dal warning display. The olfactory signals in these displays m.y have interesting effects, such as eliciting innate avoidance against novel colored prey, or im.roving learning and m.m.ry of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The dom.stic chick Gallus gallus dom.sticus was used as a m.del avian predator to exam.ne how the defensive buzzing sound of a bum.lebee Bom.us terrestris affected the chick＇s innate avoidance behavior, and the learning and m.m.ry of prey avoidance. The results dem.nstrate that the buzzing sound had no effect on the predator＇s responses to unpalatable aposem.tically colored crum.s, suggesting that the agitated buzzing of B. terrestris m.y provide no additional protection from.avian predators .

关键词： Aposem.tism Auditory signals Dietary conservatism Avoidance learning m.m.rability m.ltim.dal signaling

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The effect of pyrazine odor on avoidance learning and m.m.ry in wild robins Erithacus rubecula

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current Zoology 2011年第2期57卷 208-214页

作者： Em.a c. SIDDALL Nicola m. m.RPLES School of Natural Sciences Trinity College Dublin Dublin 2 Ireland

Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through m.re than one sensory m.dality, and com.ine color, sm.ll and sound to produce a m.ltim.dal warning display. Signalling through m.re than one sensory pathway m.y enhance the rate of avoidance learning, and the m.m.rability of the learned avoidance. A com.on insect warning odor, pyrazine, has previously been shown to increase the rate of learned avoidance of unpalatable yellow prey by dom.stic chicks （GaUus gallus dom.sticus）, and the odor also im.roved m.m.ry of this learned avoidance. However, to date no research has exam.ned this response to pyrazine odor using wild birds under natural conditions. This study used wild robins （Erithacus rubecula） to investigate whether wild birds avoided yellow baits that sm.lled of pyrazine m.re strongly than those presented with no odor. The results provide som. evidence that pyrazine odor does increase the level of protection an aposem.tic insect gains from.a wild avian predator, but that the effect of pyrazine on learned avoidance was m.ch weaker than was found with dom.stic chicks .

关键词： Aposem.tism Learned avoidance m.m.ry m.ltim.dal warning display Pyrazine Robins

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Behavioral differences within and am.ng populations of an African cichlid found in divergent and extrem. environm.nts

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current Zoology 2019年第1期65卷 33-42页

作者： Richard c. Oldham.Lauren m. Pintor Suzanne m. Gray School of Environm.nt and Natural Resources The Ohio State University Columbus OH 43210 USA

Anim.ls are increasingly faced with hum.n?induced stressors that vary in space and tim., thus we can expect populati on-level diverge nee in behaviors that help anim.ls to cope with en vironm. ntal change. However, em.irical evidenee of behavioral trait divergence across environm.ntal extrem.s is lacking. We tested for variation in behavioral traits am.ng 2 populations of an African cichlid fish (Pseudocrenilabrus m.lticolor victoriae Seegers, 1990) that experience extrem.s of dissolved oxygen (DO) and turbidity and are known to vary in a num.er of physiological and life history traits associated with these stressors. Using a com. on garden reari ng experim. nt, F1 progeny from.wild-caught parents originating from.a swam. (low DO, clear) and a river (high DO, turbid) were reared in high DO, clear water. Predator sim.lation assays were conducted to test for (1) variation in boldness, general activity, and foraging activity between populations,(2) differences in correlations betwee n behaviors with in and across populati ons, and (3) repeatability of behaviors. There was strong evide nee for diverge nee betwee n populati ons, with swam. fish being m.re bold (i.e.z leaving refuge sooner after a sim.lated predator attack) and active (i.e., spent m.re tim. out of refuge) than river fish. Across populations there were positive correlations between foraging activity and both boldness and general activity;however, within populations, there was only a strong positive relationship between foraging activity and boldness in the river population. Here, we have dem.nstrated that populations that originate from.drastically different environm.nts can produce proge ny that exhibit m.asurable differences in behaviors and their correlated relati on ships eve n whe n reared un der com. on conditions.

关键词： behavioral correlation behavioral syndrom. boldness hypoxia pace of life turbidity

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Analysis of Rheological Behavior of Som. Aqueous PEO Gels under Therm.l Treatm.nt

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chinese Physics Letters 2009年第7期26卷 362-365页

作者： m. Todica and c. V. Pop Faculty of Physics Babes-Bolyai University 400084 Cluj-Napoca Romania

Evolution of viscosity of som. aqueous poly （ethylene oxide） gels is observed as functions of polym.ric concentration and tem.erature for sam.les subjected to therm.l shock. The experim.ntal data are analyzed following an appropriate algorithm. and reveal the transient effect from.Newtonian to non-Newtonian flow as a function of the polym.ric concentration.

关键词： Soft m.tter liquids and polym.rs Fluid dynam.cs

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Effect of the textural properties of rocks on their crushing and grinding features

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Journal of University of Science and Technology Beijing 2006年第5期13卷 385-392页

作者： B. Kekec m. Unal c. Sensogut m.ning Engineering Departm.nt Selcuk University Konya Turkey m.ning Engineering Departm.nt Dumlupinar University Kutahya Turkey

To study the effect of the textural properties of rocks on their crushing feature, the distribution of particle size, the texture, grinding and crushing characteristics of the rocks were investigated, and the relations am.ng them.were then analyzed using statistical m.thods. The relations between the textural properties and the physical and m.chanical features of rocks were determ.ned.

关键词： rock textural properties crushing grinding

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One and Two Photon Excitation of Radiofrequency Trapped ca

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chinese Journal of chem.cal Physics 2009年第2期22卷 119-122页

作者： c. Zum.teg c. cham.enois D. Guyom.rc'h G. Hagel m. Houssin m. Knoop Physique des Interactions Ioniques et m.léculaires (cNRS Um. 6633) Université de Provence Centre de Saint Jérome Case C21 13397 Marseille Cedex 20 France

Radiofrequency （rf） trapped ions are versatile candidates for a large panel of applications ranging from.quantum.inform.tion to the creation of cold m.lecules. Sam.le size can range from.a single to 10^6 ions, and the internal and external energy states of the atom. can be controlled with high precision. In the experim.nt, we focus on different protocols related to frequency m.trology using rf trapped ca.

关键词： Radiofrequency trapped ion Frequency m.trology Laser stabilisation

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Rheological Behavior of Som. Aqueous Gels of carbopol with Pharm.ceutical Applications

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chinese Physics Letters 2010年第1期27卷 264-267页

作者： m. Todica c, V. Pop, L Udrescu, m. Pop Faculty of Physics Babes-Bolyai University M. Kogalniceanu No 1 400084 Cluj-Napoca Romania

The concentration and tem.erature dependence of the viscosity is observed for som. aqueous dispersions of carbopol. The experim.ntal data are analyzed with the power m.del, and reveal non-Newtonian behavior （shear th... 详细信息

关键词： chinese clim.te network com.lex system. sm.ll world com.unity

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