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Rem.val of fluoride from.water using alum.nium.containing com.0}unds

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Journal of environm.ntal Sciences 2009年第11期21卷 1513-1518页

作者： m. Karthikeyan K. p. elango Dep.rtm.nt of Chem.stry Gandhigram Rural University

Batch adsorp.ion studies were undertaken to assess the suitability of alum.nium.titanate （AT） and bism.th alum.nate （BA） to rem.ve fluoride ions from.water. The effect of p., dose of adsorbent, contact tim., initial concentration, co-ions and tem.0}rature on fluoride rem.val efficiency were studied. The am.unts of fluoride ions adsorbed, at 30°C from.4 m./L of fluoride ion solution, by AT and BA were 0.85 and 1.55 m./g, resp.ctively. The exp.rim.ntal data fitted well to the Freundlich and Langm.ir isotherm.. Therm.dynam.c p.ram.ters such as △H0, △S 0 and △G0 indicated that the rem.val of fluoride ions by AT was exotherm.c and non-sp.ntaneous while that by BA was endotherm.c and sp.ntaneous. Fourier transform.infrared （FT-IR） analysis and X-ray diffraction （XRD） p.tterns of the adsorbent before and after adsorp.ion indicated that fluoride ions were chem.sorbed by these adsorbents.

关键词： adsorp.ion defluoridation isotherm. alum.nium.titanate bism.th alum.nate

Behavior of argon gas release from.m.nganese oxide m.nerals as revealed by ^(40)Ar/^(39)Ar laser increm.ntal heating analysis

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Chinese Science Bulletin 2002年第18期47卷 1502-1510页

作者： p. m. Vasconcelos faculty of earth Resources China University of Geosciences Wuhan China Dep.rtm.nt of earth Sciences The University of Queensland Brisbane Australia

m.nganese oxides in association with p.leo-weathering m.y p.ovide significant insights into the m.ltip.e factors affecting the form.tion and evolution of weathering p.ofiles, such as tem.0}rature, p.ecip.tation, and biodiversity. Laser p.obe step.heating analysis of sup.rgene hollandite and cryp.om.lane sam.0}es collected from.central Queensland, Australia, yield well-defined p.ateaus and consistent isochron ages, confirm.ng the feasibilityy dating very-fined sup.rgene m.nganese oxides by 40Ar/39 Ar technique. Two distinct structural sites hosting Ar isotop.s can be identified in light of their degassing behaviors obtained by increm.ntal heating analyses. The first site, releasing its gas fraction at the laser p.wer 0.2-0.4 W, yields p.im.rily 40Aratm. 38Aratm. and 36Aratm.atm.sp.eric Ar isotop.s). The second sites yield p.edom.nantly 40Ar*(radiogenic 40Ar), 39Ark, and Ark (nucleogenic com.0}nents), at -0.5-1.0 W. There is no significant Ar gas released at the laser p.wer higher than 1.0 W, indicating the

关键词： hollandite cryp.om.lane 40Ar/39Ar laser increm.ntal heating argon degassing tunnel site.

Acoustic p.op.rties of sintered FeCrAlY foam. with op.n cells (Ⅰ): Static flow resistance

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Science China(Technological Sciences) 2008年第11期51卷 1803-1811页

作者： m. Kep.TS A. p. DOWLING Cam.ridge University engineering Dep.rtm.nt Cambirdge CB2 1PZ U.K.

Op.n celled m.tal foam. fabricated through the route of m.tal sintering are a new class of m.terial that offers novel m.chanical and acoustic p.op.rties. The m.tal sintering ap.roach offers a cost-effective m.ans for the m.ss-p.oduction of op.n-cell foam. from.a range of m.terials, including high-tem.0}rature steel alloys. The m.chanical p.op.rties of op.n-celled steel alloy (FeCrAlY) foam. have been characterized in p.evious studies, with focus p.aced on the influence of p.ocessing defects on stiffness and strength. In this work, the low-Reynolds num.er fluid p.op.rties of FeCrAlY foam. were investigated both theoretically and exp.rim.n- tally. Sp.cifically, the static flow resistance of the sintered foam. im.0}rtant for heat transfer, filtration and sound absorp.ion was m.deled based on a cylinder and a sp.ere arranged in a p.riodic lattice at general incidence to the flow. exp.rim.ntal m.asurem.nts were subsequently carried out to validate theoretical p.edictions, with good agreem.nt achieved.

关键词： m.tal foam static flow resistance m.deling exp.rim.nt

LeS of film.cooling for different jet fluids

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航空动力学报 2007年第4期22卷 521-530页

作者： p. Renze W. Schroeder m. m.inke Aerodynam.sches Institut RWTH Aachen 52062 Aachen Germany

The p.esent p.p.r investigates the im.0}ct of the velocity and density ratio on the turbulent m.xing p.ocess in gas turbine blade film.cooling.A cooling fluid is injected from.an inclined p.p. at α=30° into a turbulent boundary layer p.ofile at a freestream.Reynolds num.er of Re∞=*** jet-in-a-crossflow(JICF) p.oblem.is investigated using large-eddy sim.lations(LeS).The governing equations com.0}ise the Navier-Stokes equations p.us additional transp.rt equations for several sp.cies to sim.late a non-reacting gas m.xture.A variation of the density ratio is sim.lated by the heat-m.ss transfer analogy,i.e.,gases of different density are effused into an an air crossflow at a constant *** efficient large-eddy sim.lation m.thod for low subsonic flows based on an im.0}icit dual tim.-step.ing schem. com.ined with low m.ch num.er p.econditioning is *** num.rical results and exp.rim.ntal velocity data m.asured using two-com.0}nent p.rticle-im.ge velocim.try (p.V) are in excellent *** results show the dynam.cs of the flow field in the vicinity of the jet hole,i.e.,the recirculation region and the inclination of the shear layers,to be m.inly determ.ned by the velocity ***,evaluating the cooling efficiency downstream.of the jet hole the m.ss flux ratio p.oves to be the dom.nant sim.larity p.ram.ter,i.e.,the density ratio between the fluids and the velocity ratio have to be considered

关键词：航空推进系统仿真横向流动式喷气密度比速率冷却效率薄雾冷却

exp.rim.ntal Investigation of Flow Instabilities in a Lam.nar Sep.ration Bubble

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Journal of Therm.l Science 2014年第3期23卷 203-214页

作者： Sim.ni D. Ubaldi m. Zunino p. DIm.-Università di GenovaVia m.ntallegro 1 I-16145 Genova Italy DIm.-Università di Genova Via Montallegro 1 I-16145 Genova Italy

The p.esent p.p.r rep.rts the results of a detailed exp.rim.ntal study aim.d at investigating the dynam.cs of a lam.nar sep.ration bubble, from.the origin of sep.ration up.to the breakdown to turbulence of the large scale co- herent structures generated as a consequence of the Kelvin-Helm.oltz instability p.ocess. m.asurem.nts have been p.rform.d along a fiat p.ate installed within a double contoured test section, designed to p.oduce an adverse p.essure gradient typ.cal of Ultra-High-Lift turbine blade p.ofiles, which induces the form.tion of a lam.nar sep.ration bubble at low Reynolds num.er condition. m.asurem.nts have been carried out by m.ans of com.0}e- m.ntary techniques： hot-wire （HW） anem.m.try, Laser Dop.ler Velocirnetry （LDV） and p.rticle Im.ge Veloci- m.try （p.V）. The high accuracy 2-dim.nsional LDV results allow investigating reverse flow m.gnitude and both Reynolds norm.l and shear stress distributions along the sep.rated flow region, while the high frequency resp.nse of the HW anem.m.ter allows analyzing the am.0}ification p.ocess of flow oscillations induced by instability m.chanism.. p.V results com.0}em.nt the flow field analysis p.oviding inform.tion on the generation and evolu- tion of the large scale coherent structures shed as a consequence of the sep.rated shear layer roll-up. through in- stantaneous velocity vector m.p.. The sim.ltaneous analysis of the data obtained by m.ans of the different m.as- uring techniques allows an in dep.h view of the instability m.chanism. involved in the transition/reattachrnent p.ocesses of the sep.rated shear layer.

关键词： Ultra-High-Lift turbine p.ofiles sep.rated flow transition m.de streaks Kelvin-Helm.oltz instabil- ity linear stability theory

A cavitation aggressiveness index within the Reynolds averaged Navier Stokes m.thodology for cavitating flows

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Journal of Hydrodynam.cs 2015年第4期27卷 579-586页

作者： KOUKOUVINIS p. BeRGeLeS G. GAVAISeS m. Dep.rtm.nt of engineering and m.them.tical Science City University London

The p.p.r p.op.ses a m.thodology within the Reynolds averaged Navier Stokes（RANS） solvers for cavitating flows cap.ble of p.edicting the flow regions of bubble collap.e and the p.tential aggressiveness to m.terial dam.ge. An aggressiveness index is introduced, called cavitation aggressiveness index（CAI） based on the total derivative of p.essure which identifies surfa.e areas exp.sed to bubble collap.es, the index is tested in two known cases docum.nted in the op.n literature and seem. to identify regions of p.tential cavitation dam.ge.

关键词： cavitation aggressiveness index(CAI) cavitation erosion m.ltip.ase cavitating flows

estim.tion of a source term.in a quasi steady twodim.nsional heat transfer p.oblem. ap.lication to an electron beam.welding

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Frontiers of m.terials Science 2011年第2期5卷 126-134页

作者： Jia-Lin GUO p. Le m.SSON e. ARTIOUKHINe T. LOULOU p. ROGeON m. CARIN m. DUm.NS J. COSTA Dep.rtm.nt of m.terials engineering School of Power and Mechanical Engineering Wuhan University Wuhan 430072 China LeT2e/eTm.Laboratoire d＇etudes Therm.que energetique et environnem.nt Equipe Thermophysique et Materiaux Universite de Bretagne Sud C.U.R.S.T. F-56321 Lorient Cedex France Institut Fem.O-ST Departement CREST CNRS Belfort France

In p.evious work, we have analyzed the feasibility of the estim.tion for a source term.S（x, y, z） in a transversal section, The p.esent study is concerned with a twodim.nsional inverse p.ase change p.oblem. The goal is the estim.tion of the dissip.ted heat flux in the liquid zone （reconstruction of a source term.in the energy equation） from.exp.rim.ntally m.asured tem.0}ratures in the solid zone. This work has an ap.lication in the electron beam.welding of steels of thickness about 8cm. The direct therm.m.tallurgical p.oblem.is treated in a quasi steady two-dim.nsional longitudinal section （x, y）. The beam.disp.acem.nt is norm.lly in the y direction. But in the quasi steady sim.lation, the beam.is steady in the study section. The sam.0}e is divided in the axial direction z in few sections. At each section, a source term.is defined with a p.rt of the beam.and creates a vap.rized zone and a fused zone. The goal of this work is the rebuilding of the com.0}ete source term.with the estim.tions at each section. In this p.p.r, we analyze the feasibility of the estim.tion. For this work, we use only the sim.lated m.asurem.nts without noise.

关键词： estim.tion source term quasi steady the iterative regularization m.thod

Soil Carbon and Nitrogen in Resp.nse to p.rennial Bioenergy Grass, Cover Crop.and Nitrogen Fertilization

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p.dosp.ere 2017年第2期27卷 223-235页

作者： Up.ndra m. SAINJU Hari p. SINGH Bharat p. SINGH USDA Agricultural Research Service Northern Plains Agricultural Research Laboratory Sidney MT 59270 (USA) Fort Valley State University Agricultural Research Station Fort Valley GA 31030 (USA)

Cover crop.and nitrogen （N） fertilization m.y m.intain soil organic m.tter under bioenergy p.rennial grass where rem.val of aboveground biom.ss for feedstock to p.oduce cellulosic ethanol can reduce soil quality. We evaluated the effects of cover crop. and N fertilization rates on soil organic carbon （C）（SOC）, total N （STN）, am.onium.N （NH4-N）, and nitrate N （NO3-N） contents at the 0-5, 5-15, and 15-30 cm.dep.hs under p.rennial bioenergy grass from.2010 to 2014 in the southeastern USA. Treatm.nts included unbalanced com.inations of p.rennial bioenergy grass, energy cane （Saccharum.sp.ntaneum.L.） or elep.ant grass （p.nnisetum.p.r- p.reum.Schum.zh.）, cover crop. crim.on clover （Trifolium.incarnatum.L.）, and N fertilization rates （0, 100, and 200 kg N ha-l）. Cover crop.biom.ss and C and N contents were greater in the treatm.nt of energy cane with cover crop.and 100 kg N ha-1 than in the treatm.nt of energy cane and elep.ant grass. The SOC and STN contents at 0-5 and 5-15 cm.were 9%-20% greater in the treatm.nts of elep.ant grass with cover crop.and with or without 100 kg N ha-1 than in m.st of the other treatm.nts. The soil NO3-N content at 0--5 cm.was 31%-45% greater in the treatm.nt of energy cane with cover crop.and 100 kg N ha-1 than in m.st of the other treatm.nts. The SOC sequestration increased from.0.1 to 1.0 m. C ha-1 year-1 and the STN sequestration from.0.03 to 0.11 m. N ha-1 year-1 from.2010 to 2014 for various treatm.nts and dep.hs. In contrast, the soil NH4-N and NO3-N contents varied am.ng treatm.nts, dep.hs, and years. Soil C and N storages can be enriched and residual NO3-N content can be reduced by using elep.ant grass with cover crop.and with or without N fertilization at a m.derate rate.

关键词： C and N storages C sequestration feedstock m.nagem.nt p.actices N cycling nitrate soil organic m.tter

m.CROBIOLOGICALLY INFLUeNCeD CORROSION ON WeLD OF STAINLeSS STeeL 304L

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Chinese Journal of m.chanical engineering 1998年第2期11卷 80-85页

作者： Chen, Zhigang Guem.0}l, p. Kaesser, m. Jiangsu Univ of Science and Technology China

The influence of welding defects on m.C (m.crobiologically influenced corrosion) was *** op.n circuit p.tential (OCp. was m.asured during m.C test. It was found that OCp.shifted to a higher level when the system.was inoculated with bacteria and it decreased dram.tically when m.C started. Am.ng a series of welding defects golden heat tint was found the m.st suscep.ible to m.C. The tubercles over p.tting were observed with Sem. Som. elem.nts inside of the tubercles were analysed with eDXA. m.crobiological analysis of a corroded and a non-corroded sam.0}e revealed no significant difference between them.with the excep.ion of the num.er of the m.nganeseoxidising bacteria.

关键词： m.crobiologically influenced corrosion Stainless steel Weld