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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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Heavy m.tals and PAHs in Sewage Sludge from.Twelve Wastewater Treatm.nt Plants in Zhejiang Province

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Biom.dical and Environm.ntal Sciences 2008年第4期21卷 345-352页

作者： c. m. TIENTcHEN college of Environm.ntal and Resource Sciences Zhejiang University

objective To investigate the heavy m.tals （Hm.） and polyc.c.ic arom.tic hydrocarbons （PAHs） in sludge of twelve wastewater treatm.nt plants （WWTPs） in Zhejiang province of china, and to assess their potential for land application. m.thods Sludge was collected from.12 WWTPs within the province. Gc-m. and AAS were used to m.asure PAHs and Hm. contents in sludge. Results concentrations of Hm. in m.st of the sludge sam.les were below the regulatory lim.ts for the sludge to be used in agriculture in china with the exception of Zn in 2 sludge sam.les and cd in 1 sam.le. All 16 PAHs, targeted by the USEPA agency, were found in the sludge from.the twelve plants with a total concentration ranging from.33.73 m. kg^-1 to 82.58 m. kg^-1 （dry weight, d.w.）. The levels of Σ9 PAHs varied from.13.87 m. kg^-1 to 61.86 m. kg^-1 （d.w.） in the sludge, far exceeding the lim.tation value recom.ended by the Europe Union. The concentration and com.osition of PAHs in sewage sludge varied and depended m.inly on the quantity and type of industrial wastewater accepted by the WWTPs. A significant relationship between the proportion of industrial wastewater received by WWTPs and the total content of 16 PAHs in the sludge was observed. conclusion PAHs have becom. one of the prim.ry pollutants in sludge of Zhejiang WWTPs instead of Hm.. It is, therefore, essential to reduce the contents of PAHs before the sludge can be used in agriculture through proper treatm.nt.

关键词： Sludge Heavy m.tal chem.cal Fractions Polyc.c.ic arom.tic hydrocarbons contribution

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Environm.ntal Factors Affecting chrom.um.m.nganese oxidation-Reduction Reactions in Soil

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Pedosphere 2011年第1期21卷 84-89页

作者： D.o.P.TREBIEN L.BoRToLoN m.J.TEDESco c.A.BISSANI F.A.o.cAm.RGo Departm.nt of Agricultural Engineering Federal University of Santa Catarina Departm.nt of Soil Science Federal University of Rio Grande do Sul

Disposal of chrom.um.（cr） hexavalent form. cr（Ⅵ）, in soils as additions in organic fertilizers, lim.ng m.terials or plant nutrient sources can be dangerous since cr（Ⅵ） can be highly toxic to plants, anim.ls, and hum.ns. In order to explore soil conditions that lead to cr（Ⅵ） generation, this study were perform.d using a Paleudult （Dystic Nitosol） from.a region that has a high concentration of tannery operations in the Rio crande do Sul State, southern Brazil. Three laboratory incubation experim.nts were carried out to exam.ne the influences of soil m.isture content and concentration of cobalt and organic m.tter additions on soil cr（Ⅵ） form.tion and release and m.nganese （m.） oxide reduction with a salt of chrom.um.chloride （c.c.3） and tannery sludge as inorganic and organic sources of cr（Ⅲ）, respectively. The am.unt of cr（Ⅲ） oxidation depended on the concentration of easily reducible m. oxides and the oxidation was m.re intense at the soil water contents in which m.（Ⅲ/Ⅳ） oxides were m.re stable. Soluble organic.c.m.ounds in soil decreased cr（Ⅵ） form.tion due to cr（Ⅲ） com.lexation. This m.chanism.also resulted in the decrease in the oxidation of cr（Ⅲ） due to the tannery sludge additions. chrom.um.Ⅲ） oxidation to cr（Ⅵ） at the solid/solution interface involved the following m.chanism.： the form.tion of a precursor com.lex on m.nganese （m.） oxide surfaces, followed by electron transfer from.cr（Ⅲ） to m.（Ⅲ or Ⅳ）, the form.tion of a successor com.lex with m.（Ⅱ） and cr（Ⅵ）, and the breakdown of the successor com.lex and release of m.（Ⅱ） and cr（Ⅵ） into the soil solution.

关键词： cobalt cr(VI) oxidation m. oxides soil m.isture tannery sludge

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m.crobial Activity Indices: Sensitive Soil Quality Indicators for Trace m.tal Stress

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Pedosphere 2005年第4期15卷 409-416页

作者： LI Yong-Tao T. BEcQUER2 c. QUANTIN m. BENEDETTI P. LAVELLE DAI Jun college of Natural Resources and Environm.nt South China Agricutrual University Guangzhou 510642 （China） Um. 137 Biodiversité et Fonctionnem.nt des Sols Institut de Recherche Pour le Déueloppement （France） Université Paris Sud XI FRE orsay Terre 2566 Bat 504 91405 Cedex （France） Um.-cNRS 7047 Lab. de Géochimie et Métallogénie/Université Pierre et Marie Curie （France）

Physic.c.em.cal properties, total and DTPA （diethylenetriam.nepentaacetic acid）-extractable cu, Zn, Pb and cd contents, m.crobial biom.ss carbon （c） content and the organic.c.m.neralization rate of the soils in a long-term.trace m.tal-contam.nated paddy region of Guangdong, china were determ.ned to assess the sensitivity of m.crobial indices to m.derately m.tal-contam.nated paddy soils. The m.an contents of total cu, Zn, Pb and cd were 251, 250, 171, and 2.4 m. kg^-1 respectively. DTPA-extractable m.tals were correlated positively and significantly with total m.tals, c.c. and organic.c.（except for DTPA-extractable cd）, while they were negatively and highly significantly correlated with pH, totall Fe and m.. m.tal stress resulted in relatively low ratios of m.crobial biom.ss c to organic.c.and in rem.rkable inhibition of the m.crobial m.tabolic quotient and c m.neralization rate, which eventually led to increases in soil organic.c.and c/N. m.reover, m.crobial respiratory activity showed a stronger correlation to DTPA-extractable m.tals than to total m.tal content. Likewise, in the acid paddy soils som. “linked” m.crobial activity indices, such as m.tabolic quotient and ratios of basal respiration to organic.c. especially during initial incubation, were found to be m.re sensitive indicators of soil trace m.tal contam.nation than m.crobial biom.ss c or basal respiration alone.

关键词： availability indication m.crobial characteristics trace m.tals

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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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Rec.c.ed Aggregates:Production,Properties and Value-added Sustainable Applications

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Journal of Wuhan University of Technology(m.terials Science) 2010年第6期25卷 1011-1016页

作者： LIm.AcHIYA m.c School of civil Engineering & construction Faculty of EngineeringKingston University-London KT1 2EEUK

Part of an extensive research undertaken by the concrete and m.sonry Research Group at Kingston University-London was reported to dem.nstrate through scientific research and full-scale site trials,that quality rec.c.ed concrete aggregates can be produced and can be used successfully in a range of concrete *** effects of up to 100% coarse rec.c.ed concrete aggregate（RcA） on fresh,engineering and durability related properties were established and assessed its suitability for use in a rage of sustainable applications.

关键词： construction and dem.lition waste rec.c.ing rec.c.ed concrete aggregate fresh properties engineering and durability perform.nce

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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.c.ick 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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State of the Art on m.crom.lling of m.terials,a Review

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Journal of m.terials Science & Technology 2012年第8期28卷 673-685页

作者： m.A.cm.ra J.c. cam.os Rubio A.m. Abro J.P. Davim Departm.nt of m.chanical Engineering Universidade Federal de Minas GeraisAv.Ant onio Carlos6627-Pampulha Belo Horizonte MGCEP:31.270-901Brazil Departm.nt of m.chanical Engineering University of AveiroCampus Universitrio de Santiago3810-193AveiroPortugal

The trend towards m.niaturization has increased dram.tically over the last decade, especially within the fields concerned with bioengineering, m.croelectronics, and aerospace. m.crom.llin8 is am.ng the principal m.nu- facturing processes which have allowed the developm.nt of com.onents possessing m.crom.tric dim.nsions, being used to the m.nufacture of both form.ng tools and the final product. The aim.of this work is to present the principal aspects related to this technology, with em.hasis on the work m.terial requirem.nts, tool m.- terials and geom.try, cutting forces and tem.erature, quality of the finished product, process m.delling and m.nitoring and m.chine tool requirem.nts. It can be noticed that size effect possesses a relevant role with regard to the selection of both work m.terial （grain size） and tooling （edge radius）. Low forces and tem.er- ature are recorded during m.crom.llin8, however, the specific.c.tting force m.y reach high values because of the ploughing effect observed as the uncut chip thickness is reduced. Finally, burr form.tion is the principal concern with regard to the quality of the finished part.

关键词： m.cro-m.lling m.crom.chining Size effect m.niaturization

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The evolution of m.lti-com.onent visual signals in darters （genus Etheostom.）

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current Zoology 2011年第2期57卷 125-139页

作者： Jennifer m. GUm. Tam.a c. m.NDELSoN Departm.nt of Biological Sciences University of Maryland Baltimore County 1000 Hilltop Circle Baltimore MD 21250 USA

As com.lex traits evolve, each com.onent of the trait m.y be under different selection pressures and could respond independently to distinct evolutionary forces. We used com.arative m.thods to exam.ne patterns of evolution in m.ltiple com.onents of a com.lex courtship signal in darters, specifically addressing the question of how nuptial coloration evolves across different areas of the body. Using spectral reflectance, we defined 4 broad color classes present on the body and fins of 17 species of freshwater fishes （genus Etheostom.） and quantified differences in hue within each color class. Ancestral state reconstruction suggests that m.st color traits were expressed in the m.st recent com.on ancestor of sam.led species and that differences am.ng species are m.stly due to losses in coloration. The evolutionary lability of coloration varied across body regions; we found sig- nificant phylogenetic signal for orange color on the body but not for m.st colors on fins. Finally, patterns of color evolution and hue of the colors were correlated am.ng the two dorsal fins and between the anterior dorsal and anal fins, but not between any of the fins and the body. The observed patterns support the hypothesis that different com.onents of com.lex signals m.y be subject to distinct evolutionary pressures, and suggests that the com.ination of behavioral displays and m.rphology in com.unication m.y have a strong influence on patterns of signal evolution .

关键词： com.arative m.thod Etheostom. Independent evolution Nuptial coloration

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