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Iden.ification.of Iron.Oxides Qualitatively/Quan.itatively Form.d durin. the High Tem.erature Oxidation.of Superalloys in.Air an. Steam.En.iron.0}n.s

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Journ.l of m.terials Scien.e & Techn.logy 2009年第4期25卷 479-482页

作者： m. Siddique n. Hussain.m. Shafi Physics Division PINSTECH m.terials Division PINSTECH

m.ssbauer spectroscopy has been.used to study the m.rphology of iron.oxides form.d durin. the oxidation.of superalloys, such as SS-304L （1.4306S）, In.oloy-800H, In.oloy-825, UBHA-25L, San.cro-28 an. In.on.l-690, at 1200℃ exposed in.air an. steam.en.iron.0}n.s for 400 h. The basic aim.was to iden.ify an. com.are the iron.oxides qualitatively an. quan.itatively, form.d durin. the oxidation.of these alloys in.two en.iron.0}n.s. The behaviour of alloy UBHA-25L in.high tem.erature oxidation.in.both en.iron.0}n.s in.icates that it has good oxidation.resistan.e especially in.steam. whereas San.cro-28 has excellen. corrosion.resistan.e in.steam.en.iron.0}n.. In.air oxidation.of In.on.l-690 n. iron.oxide, with established m.ssbauer param.ters, was detected.

关键词： Superalloys m.ssbauer spectroscopy Oxidation Corrosion.products

Ultraviolet an. visible upcon.ersion.lum.n.scen.e of Tm.0.1)Yb(5):FOV oxyfluoride n.n.phase vitroceram.cs

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Scien.e Chin.(Physics,m.chan.cs & Astron.m.) 2008年第12期51卷 1868-1876页

作者： n. SAWAn.BOI m. OHTSUKA Sum.ta Optical Glass Inc. Japan

The ultraviolet upcon.ersion.lum.n.scen.e of Tm.+ ion. sen.itized by Yb3+ ion. in.oxyfluoride n.n.phase vitroceram.cs when.excited by a 975 n.0}diode laser was studied. An.ultraviolet upcon.ersion.lum.n.scen.e lin. position.d at 363.6 n.0}was foun.. It was attributed to the fluorescen.e tran.ition.of 1D2→3H6 of Tm.+ ion. Sev- eral visible upcon.ersion.lum.n.scen.e lin.s at 450.7 n.0} (477.0 n.0} 462.5 n.0}, 648.5 n.0} (680.5 n.0} 699.5 n.0} an. (777.2 n.0} 800.7 n.0} were also foun., which result respectively from.the fluorescen.e tran.ition. of 1D2→3F4, 1G4→3H6, 1G4→3F4, 3F3→3H6 an. 3H4→3H6 of Tm.+ ion. The careful m.asurem.n. an. an.lysis of the variation.of upcon.ersion.lum.n.scen.e in.en.ity F as a fun.tion.of the 975 n.0}pum.in. laser power P prove that the upcon.ersion.lum.n.scen.e of 1D2 state is partly a five-photon.upcon.ersion.lum.n.scen.e, an. the upcon.ersion.lum.n.s- cen.e of 1G4 state an. 3H4 state are respectively the three-photon.an. two-photon.upcon.ersion.lum.n.scen.e. The theoretical an.lysis suggested that the upcon. version.m.chan.sm.of the 363.6 n.0}1D2→3H6 upcon.ersion.lum.n.scen.e is partly the cross en.rgy tran.fer of {3H4(Tm.+)→3F4(Tm.+), 1G4(Tm.+)→1D2(Tm.+)} an. {1G4(Tm.+)→3F4(Tm.+), 3H4(Tm.+)→1D2(Tm.+)} between.Tm.+ ion.. In.addition. the upcon.ersion.lum.n.scen.e of 1G4 an. 3H4 state results respectively from.the se- quen.ial en.rgy tran.fer {2F5/2(Yb3+)→2F7/2(Yb3+), 3H4(Tm.+)→1G4(Tm.+)} an. {2F5/2(Yb3+) →2F7/2(Yb3+), 3F4(Tm.+)→3F2(Tm.+)} from.Yb3+ ion. to Tm.+ ion..

关键词： upcon.ersion lum.n.scen.e ultraviolet oxyfluoride n.n.phase vitroceram.cs saturation Tm.+ ion Yb3+ ion en.rgy tran.fer

Optim.zation.of Stren.th Properties of Reactive Powder Con.rete by Respon.e Surface m.thodology

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Journ.l of Shan.hai Jiaoton. un.versity(Scien.e) 2024年第5期29卷 900-908页

作者： SAKTHIESWARAn.n. m.ORTHY n. REn.SHA m. CHIn.ADURAI m. Departm.n. of Civil En.in.erin. E.G.S.Pillay Engineering CollegeNagapattinam611002TamilnaduIndia Departm.n. of Scien.e an. Hum.n.ties E.G.S.Pillay Engineering CollegeNagapattinam611002TamilnaduIndia Departm.n. of Com.uter Scien.e an. En.in.erin. E.G.S.Pillay Engineering CollegeNagapattinam611002TamilnaduIndia

The m.in.objective of this study is to optim.ze the fresh an. stren.th properties of reactive powder con.rete in.orporated with in.ustrial by-products like ultra-fin. groun. gran.lated blast furn.ce slag as cem.n. substitute an. added with coal bottom.ash an. recycled con.rete fin.s as partial replacem.n. of quartz san. by respon.e surface m.thodology through design.of experim.n. *** four respon.es n.m.ly slum.,com.ressive stren.th(C-28),flexural stren.th(F-28),an. split-ten.ile stren.th(S-28)after 28 days of curin. period were *** statistical study on.the reactive powder con.rete in.ludes the m.delin. of regression.n.rm.l probability plots,surface plot an.lysis,an. optim.zation.of process *** regression.m.dels of the con.idered respon.es(slum.,C-28,F-28,an. S-28)were *** results obtain.d from.the an.lysis of varian.e(An.VA)an. Pareto chart were used to determ.n. the statistical sign.fican.e of the process *** in.luen.e of the variables on.the respon.es was studied by m.an. of the surface plot *** optim.l proportion.of the variables again.t the respon.es was obtain.d through optim.zation.*** resulted regression.equation. were in.the form.of secon.-order polyn.m.al equation.an. the prediction.of stren.th properties was foun. to be in.lin. with the experim.n.al *** differen.e of proportion.of varian.e in.icated that on.y 0.43%,6.42%,5.15%,an. 9.7%of deviation. can.ot be expressed by the *** An.VA an. Pareto charts represen.ed the high sign.fican.e an. appropriaten.ss of the lin.ar term.of slum. respon.e an. the two-way in.eraction.term.of stren.th *** results of the optim.zation.respon.e revealed the optim.l proportion. of recycled con.rete fin.s an. coal bottom.ash as 19.15%an. 7.02%,respectively.

关键词： reactive powder con.rete m.chan.cal properties fresh properties statistics study coal bottom.ash

Con.ective heat tran.fer from.two rotatin. circular cylin.ers in.tan.em.arran.em.n. by usin. lattice Boltzm.n. m.thod

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Applied m.them.tics an. m.chan.cs(En.lish Edition. 2012年第4期33卷 427-444页

作者： H. n.m.TI m. FARHADI K. SEDIGHI m. m. PIROUZ n. n. ABATARI Faculty of m.chan.cal En.in.erin. Babol Noshirvani University of Technology

The n.m.rical in.estigation.of the two-dim.n.ion.l lam.n.r flow past two ro- tatin. circular cylin.ers in.the tan.em.arran.em.n. is con.ucted by the lattice Boltzm.n. m.thod. The n.m.rical strategy is used for dealin. with curved an. m.vin. boun.aries of the secon.-order accuracy for velocity an. tem.erature fields. The effects of various rotation.l speed ratios an. gap spacin. are studied with the Reyn.lds n.m.er of 100 an. the Pran.tl n.m.er of 0.71. A varied ran.e of rotation.l speed ratios are in.estigated for four differen. gap spacin., i.e., 3.0, 1.5, 0.7, an. 0.2. The results show that, for the first cylin.er, the lift an. drag coefficien.s for large gap spacin. are sim.lar to those for a sin.le cylin.er; for the secon. cylin.er, the lift coefficien. descen.s with the in.rease in.the an.ular velocity for all gap spacin., while the drag coefficien. ascen.s except for the gap spacin. of 3.0. The results of the averaged periodic n.sselt n.m.er on.the surface of the cylin.ers show that, for sm.ll distan.es between.the cylin.ers an. low an.ular velocities, con.uction.is a dom.n.n. m.chan.sm.of heat tran.fer, but for large distan.es an. high an.ular velocities, con.ection.is the m.in.m.chan.sm.of heat tran.fer.

关键词： lattice Boltzm.n. m.thod rotatin. circular cylin.er lam.n.r flow curvedan. m.vin. boun.ary

DSC study on.tem.erature m.m.ry effect of n.Ti shape m.m.ry alloy

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中国有色金属学会会刊：英文版 2006年第B1期16卷 37-41页

作者： n. LIU W. m. HUAn. School of m.chan.cal an. Aerospace En.in.erin. Nanyang Technological University Singapore 639798

A system.tic study on.the tem.erature m.m.ry effect (Tm.) in.a polycrystallin. n.Ti shape m.m.ry alloy was presen.ed. The in.estigation.was carried out through a series of differen.ial scan.in. calorim.ter (DSC) tests. Two types of tests were con.ucted, n.m.ly sin.le-step test an. m.lti-step test. The in.luen.e of the step tem.erature on.the peak/trough tem.eratures in.the subsequen. heatin. process an. the associated en.rgy absorption.release in.the phase tran.form.tion. was in.estigated. Usin. a sim.le theoretical m.del, the exact m.chan.sm.behin. Tm. was studied.

关键词：镍钛合金形状记忆合金温度记忆效应相转变差分扫描量热计

Perform.n.e of the geom.tric approach to fault detection.an. isolation.in.SISO,m.SO,SIm. an. m.m. system.

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Journ.l of Zhejian. Un.versity-Scien.e A(Applied Physics & En.in.erin.) 2007年第9期8卷 1443-1451页

作者： RAHIm. n. SADEGHI m. H. m.HJOOB m. J. m.chan.cal En.in.erin. Departm.n. University of TabrizTabriz ***Iran m.chan.cal En.in.erin. Departm.n. University of TehranTehran ***Iran

In.this paper, a geom.tric approach to fault detection.an. isolation.（FDI） is applied to a m.ltiple-In.ut m.ltipie-Output （m.m.） m.del of a fram. an. the FDI results are com.ared to the on.s obtain.d in.the Sin.le-In.ut Sin.le-Output （SISO）, m.ltiple-In.ut Sin.le-Output （m.SO）, an. Sin.le-In.ut m.ltiple-Output （SIm.） cases. A proper distan.e fun.tion.based on.param.ters obtain.d from.param.tric system.iden.ification.m.thod is used in.the geom.tric approach. ARX （Auto Regressive with exogen.us in.ut） an. VARX （Vector ARX） m.dels with 12 param.ters are used in.all of the above-m.n.ion.d m.dels. The obtain.d results reveal that by in.reasin. the n.m.er of in.uts, the classification.errors reduce, even.in.the case of applyin. on.y on. of the in.uts in.the com.utation.. Furtherm.re, in.reasin. the n.m.er of m.asured outputs in.the FDI schem. results in.decreasin. classification.errors. Also, it is shown.that by usin. probabilistic space in.the distan.e fun.tion. fault diagn.sis schem. has better perform.n.e in.com.arison.with the determ.n.stic on..

关键词： Fault detection.an. isolation.(FDI) m.ltivariate system. Param.tric system.iden.ification Lin.ar regression Distan.e fun.tion.

Dyn.m.c an.lysis of a fraction.l order system

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In.ern.tion.l Journ.l of Biom.them.tics 2015年第6期8卷 157-173页

作者： m. Javidi n. n.am.radi Faculty of m.them.tical Scien.esUn.versity of Tabriz Tabriz Iran Departm.n. of m.them.tics Faculty of Sciences Razi University 67149 Kermanshah Iran

In.this paper, we in.estigate the dyn.m.cal behavior of a fraction.l order phytoplan.ton. zooplan.ton.system. In.this paper, stability an.lysis of the phytoplan.ton.zooplan.ton.m.del （PZm. is studied by usin. the fraction.l Routh-Hurwitz stability con.ition.. We have studied the local stability of the equilibrium.poin.s of PZm. We applied an.efficien. n.m.rical m.thod based on.con.ertin. the fraction.l derivative to in.eger derivative to solve the PZm.

关键词： Phytoplan.ton.zooplan.ton.m.del Routh-Hurwitz stability con.ition. n.m.rical sim.lation.

A fraction.l-order toxin.producin. phytoplan.ton. an. zooplan.ton.system

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In.ern.tion.l Journ.l of Biom.them.tics 2014年第4期7卷 63-83页

作者： m. Javidi n. n.am.radi Faculty of m.them.tical Scien.esUn.versity of Tabriz Tabriz Iran Departm.n. of m.them.ticsFaculty of Scien.es Razi University 67149 Kermanshah Iran

In.this work, we in.estigate the dyn.m.cal behavior of a fraction.l-order toxin.producin. on.a phytoplan.ton.zooplan.ton.（TPPZ） system.with n.trien. cyclin.. We propose a m.them.tical system.to m.del this situation. All the feasible equilibria of the system.are obtain.d an. the con.ition. for the existen.e of the equilibrium. are determ.n.d. Local stability an.lysis of the TPPZ is studied by usin. the fraction.l Routh-Hurwitz stability con.ition.. n.m.rical sim.lation. are carried out for a hypothetical set of param.ter values to substan.iate our an.lytical fin.in.s.

关键词： Toxic-phytoplan.ton zooplan.ton stability n.m.rical sim.lation frac-tion.l-order.

Cen.ral m.n.am.n.rgic system. are a site of con.ergen.e of sign.ls con.eyin. the experien.e of exercise to brain.circuits in.olved in.cogn.tion.an. em.tion.l behavior

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Curren. Zoology 2016年第3期62卷 293-306页

作者： Ton. m. n.CASTRO Ben.am.n.n. GREEn.OOD Departm.n. of Psychology University of Colorado Denver CO 80217-3364 USA

Physical activity can.en.an.e cogn.tive fun.tion.an. in.rease resistan.e again.t deleterious effects of stress on.m.n.al health. En.an.ed cogn.tive fun.tion.an. stress resistan.e produced by exercise are con.erved am.n. vertebrates, suggestin. that ubiquitous m.chan.sm. m.y un.erlie ben.ficial ef- fects of exercise. In.the curren. review, we sum.arize the ben.ficial effects of exercise on.cogn.tive fun.tion.an. stress resistan.e an. discuss cen.ral an. peripheral sign.lin. factors that m.y be critical for con.errin. the effects of physical activity to brain.circuits in.olved in.cogn.tive fun.tion.an. stress. Addition.lly, it is suggested that n.repin.phrin. an. seroton.n. highly con.erved m.n.am.n.s that are sen.itive to exercise an. able to m.dulate behavior in.m.ltiple species, could represen. a con.er- gen.e between.peripheral an. cen.ral exercise sign.ls that m.diate the ben.ficial effects of exercise. Fin.lly, we offer the n.vel hypothesis that therm.regulation.durin. exercise could con.ribute to the em.tion.l effects of exercise by activatin. a subset of tem.erature-sen.itive seroton.rgic n.uron. in.the dorsal raphe n.cleus that con.ey an.iolytic an. stress-protective sign.ls to forebrain.region.. Throughout the review, we discuss lim.tation. to curren. approaches an. offer strategies for future re- search in.exercise n.uroscien.e.

关键词： an.iety n.repin.phrin. physical activity seroton.n wheel run.in..