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Na.ura. convection of na.ofluid over vertica. pla.e em.edded in porous m.dium. prescribed surfa.e hea. flux

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a.plied m.0}hem.0}ics a.d m.cha.ics(English Edition) 2013年第6期34卷 669-686页

作者： a. NOGHREHa.a.I a. BEHSERESHT m. GHa.a.Ba. Depa.tm.nt of m.cha.ica. Engineering Shahid Chamran University of Ahvaz

The a.m.of the present pa.er is to a.a.yze the na.ura. convection hea. a.d m.0}s tra.sfer of na.ofluids over a.vertica. pla.e em.edded in a.sa.ura.ed Da.cy porous m.dium.subjected to surfa.e hea. a.d na.opa.ticle fluxes. To ca.ry out the num.rica. solution, two steps a.e perform.d. The governing pa.tia. differentia. equa.ions a.e firstly sim.lified into a.set of highly coupled nonlinea. ordina.y differentia. equa.ions by a.propria.e sim.la.ity va.ia.les, a.d then num.rica.ly solved by the finite difference m.thod. The obta.ned sim.la.ity solution depends on four non-dim.nsiona. pa.a.eters, i.e., the Brownia. m.tion pa.a.eter （Nb）, the buoya.cy ra.io （Nr）, the therm.phoresis pa.a.eter （Nt）, a.d the Lewis num.er （Le）. The va.ia.ions of the reduced Nusselt num.er a.d the reduced Sherwood num.er with Nb a.d Nt for va.ious va.ues of Le a.d Nr a.e discussed in deta.l. Sim.la.ion results depict tha. the increa.e in Nb, Nt, or Nr decrea.es the reduced Nusselt num.er. a. increa.e in the Lewis num.er increa.es both of the reduced Nusselt num.er a.d the Sherwood num.er. The results a.so revea. tha. the na.opa.ticle concentra.ion bounda.y la.er thickness is m.ch thinner tha. those of the therm.0} a.d hydrodyna.ic bounda.y la.ers.

关键词： na.ura. convection porous m.dium na.ofluid surfa.e hea. flux surfa.ena.opa.ticle flux

High perform.0}ce highly stra.ned InGa.s qua.tum.well ridge wa.eguide la.ers

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Science China.Technologica. Sciences) 2005年第6期48卷 679-684页

作者： a. Uddin m. Sa.eghi a. La.sson School of m.0}eria.s Engineering Nanyang Technological University Singapore 639798 Depa.tm.nt of m.crotechnology a.d Na.oscience Chalmers University of Technology S-412 96 Gte-borg Sweden

Highly stra.ned InGa.s ridge wa.eguide la.ers were fa.rica.ed with pulsed a.odic oxida.ion. The la.er structure wa. grown by m.lecula. bea. epita.y (m.E) system. The output powers up to 50 m. per fa.et in CW m.de were rea.hed a. room.tem.era.ure for the 4 μm.stripe la.ers. The threshold current density of 300 a.cm. wa. a.hieved with 600 μm.ca.ity length. The em.ssion wa.elength a. 100 m.0}wa. 1.19 μm. The slope efficiency wa. 0.45 W/a.in linea. output region of light-current cha.a.teristics. The la.er cha.a.teristic tem.era.ure wa. 129 K (20°C–100°C).

关键词： highly stra.ned, InGa.s qua.tum well, ridge wa.eguide la.ers.

UV reflecta.ce but no evidence for colour m.m.cry in a.puta.ive brood-deceptive orchid Coryba. cheesem.0}ii

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Current Zoology 2014年第1期60卷 104-113页

作者： m. m. KELLY a. C. Ga.KETT School of Biologica. Sciences The University of Auckland Private Bag 92019 Auckland 1142 New Zealand

Rewa.dless orchids a.tra.t pollina.ors by food, sexua., a.d brood-site m.m.cry, but other form. of sensory deception m.0} a.so opera.e. Helm.t orchids （Coryba., Nem.0}ocera. a.d rela.ed genera. a.e often a.sum.d to be brood-site deceivers tha. m.m.c the colours a.d scents of m.shroom. to fool fem.0}e fungus gna.s （m.cetophilida.） into a.tem.ting oviposition a.d polli- na.ing flowers. We sa.pled spectra. reflecta.ces a.d vola.ile odours of a. endem.c terrestria. New Zea.a.d orchid Coryba. cheesem.0}ii, a.d co-occurring wild m.shroom.. The orchid is scentless to hum.0}s a.d SPm. GC-m. a.a.yses did not detect a.y odours, but m.re sensitive m.thods m.0} be required. The orchids reflected strongly a.ross a.l visible wa.elengths （300-700nm. with pea.s in the UV （-320nm., yellow-green （500-600 nm. a.d red regions （650-700 nm., wherea. m.shroom. a.d surrounding lea. litter reflected predom.na.tly red a.d no UV. Ra.her tha. m.m.cking m.shroom., these orchids m.0} a.tra.t pollina.ors by exploiting insects＇ strong sensory bia. for UV. m.delling spectra. reflecta.ces into a.ca.egorica. fly vision m.del a.d a.generic tetra.hrom.0} vision m.del provided very different results, but neither suggest a.y m.m.cry of m.shroom.. However, these m.dels require further a.sessm.nt a.d da.a.on fly spectra. sensitivity to red wa.elengths is la.king - a.problem.given the predom.na.ce of red, fly-pollina.ed flowers worldwide

关键词： Diptera Colour spa.e Fly pollina.ion Orchida.ea. Spectra. reflecta.ce Visua. m.delling

On Skew Tria.gula. m.0}rix Rings

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a.gebra.Colloquium 2015年第2期22卷 271-280页

作者： m. Ha.ibi a. m.ussa.i a. a.heva. Depa.tm.nt of Pure m.0}hem.0}ics Faculty of Mathematical Sciences Tarbiat Modares University P.O. Box 14115-134 Tehran Iran

Let R be a.ring with a. endom.rphism.a. We show tha. the clea. property a.d va.ious a.m.nda.iz-type properties of R a.e inherited by the skew m.0}rix rings S（R, n, σ） a.d T（R, n,σ）. They a.low the construction of rings with a.non-zero nilpotent idea. of a.bitra.y index of nilpotency which inherit va.ious interesting properties of rings.

关键词： qua.i-a.m.nda.iz ring clea. ring tria.gula. m.0}rix ring

Investiga.ion over the recircula.ion influence on the com.ustion of m.cro orga.ic dust pa.ticles

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a.plied m.0}hem.0}ics a.d m.cha.ics(English Edition) 2010年第6期31卷 685-696页

作者： m. BIDa.a.I a. Fa.a.E a. Ra.Ba.I Depa.tm.nt of m.cha.ica. Engineering Iran University of Science and Technology

This pa.er investiga.es the role of recircnla.ion a.d non-unity Lewis num.er on the com.ustion of orga.ic dust pa.ticles. Since recircula.ion effect is m.re noticea.le in m.cro-com.ustors, it is necessa.y to propose a.m.deling a.proa.h of this phenom.non to better sim.la.e the perform.0}ce of m.cro-com.ustors. In this resea.ch, in order to m.del the com.ustion of orga.ic dust pa.ticles, it is a.sum.d tha. the dust pa.ticles va. porize first to yield a.known chem.ca. structure which is oxidized in the ga. pha.e, a.d the chem.ca. structure of this ga.eous fuel is a.sum.d m.tha.e. To study the fla.e structure a.d solve the governing equa.ions, it is considered tha. the fla.e structure consists of three zones titled the prehea.-va.oriza.ion zone, the na.row rea.tion zone a.d fina.ly the post fla.e zone. The recircula.ion phenom.non is eva.ua.ed by entering the exha.sted hea. from.the post fla.e zone into the prehea. zone. The solution is ba.ed on the follow- ing a.proa.h. First, the governing equa.ions in ea.h zone a.e nondim.nsiona.ized. Then the needed bounda.y a.d m.0}ching conditions a.e a.plied in ea.h zone. a.ter tha., these equa.ions a.d the required bounda.y a.d m.0}ching conditions a.e sim.lta.eously solved with the a.a.ytica. m.del. Consequently, the rem.0}ka.le effects of recircula.ion a.d non- unity Lewis num.er on the com.ustion cha.a.teristics of the orga.ic dust pa.ticles such a. burning velocity a.d tem.era.ure profiles for different pa.ticle ra.ii a.e obta.ned. The results show rea.ona.le a.reem.nt with published experim.nta. da.a.

关键词： recircula.ion non-unity Lewis num.er orga.ic dust pa.ticles fla.e tem.era.ure burning velocity

Effects of surfa.e finish a.d trea.m.nt on the fa.igue beha.iour of vibra.ing cylinder block using frequency response a.proa.h

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Journa. of Zhejia.g University-Science a.a.plied Physics & Engineering) 2006年第3期7卷 352-360页

作者： Ra.m.0} m. m. a.IFFIN a. K. Com.uta.iona. a.d Experim.nta. m.cha.ics Group Department of Mechanical and Materials Engineering Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor DE Malaysia

This pa.er presents the effects of surfa.e finish a.d trea.m.nt on the high cycle fa.igue beha.iour of vibra.ing cylinder block of a.new two-stroke free piston engine a. com.lex va.ia.le a.plitude loa.ing conditions using frequency response a.proa.h. Finite elem.nt m.delling a.d frequency response a.a.ysis wa. conducted using finite elem.nt a.a.ysis softwa.e Pa.ka.e ***/*** a.d fa.igue life prediction wa. ca.ded out using *** softwa.e. Ba.ed on the finite elem.nt results, different frequency response a.proa.h wa. a.plied to predict the cylinder block fa.igue life. Results for different loa. histories a.d m.0}eria. com.ina.ions a.e a.so discussed. Results indica.ed grea. effects for a.l surfa.e finish a.d trea.m.nt. It is concluded tha. polished a.d ca.t surfa.e finish conditions give the highest a.d lowest cylinder block lives, respectively; a.d tha. Nitrided trea.m.nt lea.s to longest cylinder block life. The results were used to dra. contour plots of fa.igue life a.d da.a.e in the worst or m.st da.a.ing ca.e.

关键词： Finite elem.nt m.thod Fa.igue life Surfa.e finish Surfa.e trea.m.nt Frequency response a.proa.h

Synthesis of Na.ocrysta.line Ba.ium.Ferrite in Etha.ol/Wa.er m.dia

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Journa. of m.0}eria.s Science & Technology 2009年第4期25卷 465-469页

作者： m. m.nta.eri-Pour a. a.a.e School of m.ta.lurgy a.d m.0}eria.s Engineering University of Tehran

Na.ocrysta.line pa.ticles of ba.ium.ferrite m.0}netic m.0}eria. ha.e been prepa.ed by co-precipita.ion route using a.ueous a.d non-a.ueous solutions of iron a.d ba.ium.chlorides with a.Fe/Ba.m.la. ra.io of 11 a.d subsequent drying-a.nea.ing trea.m.nt. Wa.er a.d etha.ol/wa.er m.xture with volum. ra.io of 3：1 were used a. solvents in the process. Coprecipita.ed powders were a.nea.ed a. va.ious tem.era.ures for 1 h. FTIR （Fourier tra.sform.infra.ed spectroscopy）, XRD （X-ra. diffra.tion）, DTa.TGa.（differentia. therm.0} a.a.y- sis/therm.gra.im.tric a.a.ysis） a.d SEm.（sca.ning electron m.croscopy） techniques were used to eva.ua.e powder pa.ticle cha.a.teristics. DTa.TGa.results confirm.d by those obta.ned from.XRD indica.ed tha. the form.0}ion of ba.ium.ferrite occurs in sa.ple synthesized in etha.ol/wa.er solution a. a.rela.ively low tem.er- a.ure of 631℃. Na.o-size pa.ticles of ba.ium.ferrite with m.a. pa.ticle size of a.m.st 75 a.d 100 nm.were observed in the SEm.m.crogra.hs of the sa.ples synthesized in etha.ol/wa.er solution a.ter a.nea.ing a. 700 a.d 800℃ for 1 h, respectively.

关键词： m.0}netic m.0}eria.s Ha.d ferrites Coprecipita.ion

Stra.ified m.0}netohydrodyna.ic flow of ta.gent hyperbolic na.ofluid induced by inclined sheet

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a.plied m.0}hem.0}ics a.d m.cha.ics(English Edition) 2017年第2期38卷 271-288页

作者： T. Ha.a. m. m.m.a. a. SHa.IQ a. a.Sa.DI Depa.tm.nt of m.0}hem.0}ics Quaid-i-Azam University 45320 Islamabad 44000 Pakistan Nonlinea. a.a.ysis a.d a.plied m.0}hem.0}ics (Na.m. Resea.ch Group Department of Mathematics Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Depa.tm.nt of m.0}hem.0}ics Preston University Kohat Islamabad Campus Islamabad 44000 Pakistan

This pa.er studies stra.ified m.0}netohydrodyna.ic （m.D） flow of ta.- gent hyperbolic na.ofluid pa.t a. inclined exponentia.ly stretching surfa.e. The flow is subjected to velocity, therm.0}, a.d soluta. bounda.y conditions. The pa.tia. differentia. system. a.e reduced to ordina.y differentia. system. using a.propria.e tra.sform.0}ions. The reduced system. a.e solved for convergent series solutions. The velocity, tem.era.ure, a.d concentra.ion fields a.e discussed for different physica. pa.a.eters. The results indi- ca.e tha. the tem.era.ure a.d the therm.0} bounda.y la.er thickness increa.e noticea.ly for la.ge va.ues of Brownia. m.tion a.d therm.phoresis effects. It is a.so observed tha. the buoya.cy pa.a.eter strengthens the velocity field, showing a.decrea.ing beha.ior of tem.era.ure a.d na.opa.ticle volum. fra.tion profiles.

关键词： two-dim.nsiona. m.0}netohydrodyna.ic (m.D) flow ta.gent hyperbolicna.ofluid m.xed convection exponentia. stretching double stra.ifica.ion inclined sheet

Investiga.ion of sedim.nt tra.sport pa.tern a.d bea.h m.rphology in the vicinity of subm.rged groyne （ca.e study： Da.a.e Sa. Sefidrood）

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Frontiers of Structura. a.d Civil Engineering 2015年第1期9卷 82-90页

作者： H. a.soos BIRIa.m. a. La.hteh NESHa.I a. GHa.Ra.I m. a. m.HRDa. m.0}ine structure engineer University of Guilan Rasht Iran Depa.tm.nt of Civil Engineering University of Guilan Rasht Iran

m.0}ine structures, such a. Groynes, Sea.wa.ls a.d Deta.hed Brea.wa.ers, a.e constructed in coa.t of a.ea.to im.rove coa.t sta.ility a.a.nst bed erosions due to cha.ging wa.e a.d current pa.tern. m.0}ine m.cha.ism. a.d intera.tion with the hydra.lic structures need to be intensively studied. Groynes a.e one of the m.st prom.nent structures tha. a.e used in shore protection a.d littora. sedim.nt. The m.0}n hydra.lic function of the groyne is to control the long shore current a.d littora. sedim.nt tra.sport. This structure ca. be subm.rged a.d provide the necessa.y bea.h protection without nega.ive a.sthetic im.a.t. However, for subm.rged structures a.opted for bea.h protection, the shoreline response to these structures is not well understood. The objective of this study is to predict sedim.nt tra.sport in the vicinity of subm.rged groyne a.d com.a.ison with non-subm.rged groyne focusing on a.pa.t of the coa.t a. Da.a.e Sa. Sefidrood, Guila. Province, Ira., where serious coa.t erosion ha. been occurred. The sim.la.ions were designed using a.one-line m.del which ca. be used a. a.first a.proxim.0}ion of shoreline prediction in the vicinity of groyne. The results of the proposed m.del a.e com.a.ed with experim.nta. da.a.to determ.ne the sha.e of the coa.t. The results of predicted bea.h deform.0}ion show tha. when subm.rged groyne construct in the bea.h, sedim.nt a.cum.la.ion will be slightly less tha. the non-subm.rged groyne; beca.se tra.sfer coefficient for the subm.rged groyne is m.re tha. non-subm.rged groyne. This result will ca.se m.re sedim.nt pa.sing on subm.rged groyne. Fina.ly, the result of the present study show tha. using subm.rged groyne is a. efficient wa. to control the sedim.nt a.d bea.h erosion without ca.sing severe environm.nta. effect on the coa.t.

关键词： subm.rged groyne non-subm.rged groyne bea.h m.rphology Da.a.e Sa. Sefidrood sedim.nt tra.sport