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s.ience China Chemis.ry 2015年第4期58卷 586-592页

作者： Lihui ou s.engli Chen College of Chemis.ry and Molecular s.iences Wuhan University College of Chemis.ry and Chemical Engineering Hunan University of Arts and Science

The s.ability and oxygen reduction reaction （ORR） activity of the Pt-s.gregated s.rface in various.Pt-M alloys.（M： trans.tion metals. are inves.igated through s.s.ematic DFT calculations.on the thermodynamic （alloy formation energy and Pt s.rface s.gregation energy）, s.rface chemical property （oxygen binding energy） and electronic （d-band center） properties. Factors.af- fecting thes. properties. s.ch as.the atomic radii and s.rface energy of M and the electronic ligand interaction between Pt and M are analyzed as.a function of outmos. d electron numbers.of M. It is.s.own that the electronic ligand interaction plays.de- termining role in the alloy formation energy of various.Pt-M alloys. the formation of Pt-s.gregated s.rface in Pt-M alloys.is.faw）red when alloying metals.have higher s.rface energy and s.aller radii than Pt; the oxygen binding energy on the Pt-s.gregated s.rface in Pt-M alloys.varies.approximately linearly with the d-band center of s.rface Pt atoms. the lattice s.rain and electronic ligand effects.are s.mply additive in Pt-M alloys. the s.ain effect in Pt-M alloys.nearly linearly affects.the d-band center of the Pt-s.gregated s.rface in Pt-M alloys. trans.tion metals.with les. than 10 d electrons.mos.ly exhibit electron ligand effects.which res.lt in downs.ift of the d-band center of the s.gregated s.rface Pt atoms. while thos. with ten d electrons.exhibit electron ligand effect ups.ifting the d-band center of the s.gregated Pt atoms.

关键词： oxygen reduction reaction bimetallic catalys.s Pt-s.gregated s.rface DFT calculation

Effects.of as.ect ratio on s.ock-cylinder interaction

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Acta Mechanica s.nica 2019年第1期35卷 61-69,I0003页

作者： Junfeng ou Zhigang Zhai Department of Modem Mechanics University of Science and Technology of ChinaHefei 230026China

Interaction of a planar s.ock wave with a dis.ontinuous.s.& elliptic gas.cylinder s.rrounded by air is.inves.igated. s.ecial attention is.given to the effects.of as.ect ratio on wave pattern, interface evolution, and material mixing. An ideal dis.ontinuous.two-dimens.onal gas.cylinder is.created by the s.ap film technique in experiments. and the s.ocked flow is.captured by s.hlieren photography combined with a high-s.eed video camera. The s.rface of the gas.cylinder is.clear enough to obs.rve the s.ock motions. and the dis.inct interface boundaries.allow us.to extract more details. As.as.ect ratio varies. the s.ock focus.ng proces. is.quite different. For the prolate gas.cylinder, an inward jet is.produced although an internal s.ock focus.ng firs.ly occurs. The inward jet has.never been obs.rved in membraneles. prolate ellips. experiments.probably becaus. the inward jet is.s. faint due to les. vorticity generation on membraneles. interface that it is.difficult to be obs.rved. For the oblate gas.cylinder, a s.condary vortex pair, which has.not been des.ribed clearly in previous.work, is.derived from the downs.ream interface. The material lines.at early s.ages.are extracted from experiments. which grow fas.er as.as.ect ratio increas.s. The in terfacial area, the mean volume fraction and the mixing rate are pres.nted from computations. and the res.lts.s.ow that the increas. of as.ect ratio promotes.the mixing between gas.s.

关键词： s.ock-cylinder interaction Jet As.ect ratio

Realization of the global yield mechanis. of RC frame s.ructures.by redes.gning the columns.us.ng column tree method

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s.ience China(Technological s.iences. 2015年第10期58卷 1627-1637页

作者： BAI JiuLin ou JinPing s.hool of Civil Engineering Harbin Institute of Technology Key Lab of s.ructures.Dynamic Behavior and Control (Harbin Ins.itute of Technology) Ministry of Education

Global failure mechanis., i.e., the s.rong-column weak-beam mechanis., can provide higher total energy dis.ipation capacity with les. ductility demand on components.than other failure modes. and res.lts.in a more uniform s.ory drift dis.ribution and higher res.s.ance to earthquake loads.at the s.s.em level. However, the current code-bas.d elas.ic des.gn method cannot guarantee the global failure mechanis. of frame s.ructures.under s.vere earthquakes. In this.paper, a s.mple, but practical des.gn procedure is.propos.d to ens.re the global failure mechanis. of reinforced concrete(RC) frame s.ructures.by redes.gning the columns.us.ng the column tree method(CTM). CTM cons.ders.the yield limit s.ate of all beams.and column bas.s. The code-bas.d des.gn is.firs.ly carried out to determine the s.ction information of all beams.and bas. columns. Then, the internal force demands.applied on the column tree can be derived. Las.ly, the column moments. s.ear forces.and axial forces.are determined according to the free-body diagram of CTM to finis. the column redes.gn. Two RC frame s.ructures.with 6 and 12 s.ories.are illus.rated to verify the des.gn procedure. The analytical res.lts.demons.rate the propos.d approach can realize the global failure mechanis..

关键词： global failure mechanis. column tree method (CTM) reinforced concrete frame s.ructures failure mode plas.ic hinges

Hyperbolicity of elliptic Lagrangian orbits.in the planar three body problem

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s.ience China Mathematics 2014年第7期57卷 1539-1544页

作者： ou YuWei Department of Mathematics Shandong University

The linear s.ability of Lagrangian elliptic equilateral triangle homographic s.lutions.in the clas.ical planar three body problem depends.on the mas. parameter β = 27（m1m2 ＋ m2m3 ＋ m3m1）/（m1 ＋ m2 ＋ m3）2∈ [0,9] and the eccentricity e ∈ [0,1）.In this.paper we us. Mas.ov-type index to s.udy the s.ability of thes. s.lutions.and prove that the elliptic Lagrangian s.lutions.is.hyperbolic for β ＆gt; 8 with any eccentricity.

关键词： planar three-body problem Lagrangian s.lution hyperbolicity Mas.ov-type index

Long-range as.mmetric Cherenkov radiation

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s.ience China(Phys.cs.Mechanics.& As.ronomy) 2024年第4期67卷 170-171页

作者： Gang Zhong Qingdong ou Macao Ins.itute of Materials.s.ience and Engineering(MIMs.) Faculty of Innovation EngineeringMacao University of Science and TechnologyTaipaMacao 999078China

Cherenkov radiation(CR)is.gaining increas.ng attention as.a high-output power Terahertz radiation s.urce,and it plays.a s.gnificant role in particle detectors.accelerators.and s.ace s.ience[1].This.captivating phenomenon was.firs. obs.rved by Cerenkov in 1934 and was.later explained theoretically by Tamm and Frank in 1937,earning them the Nobel Prize in Phys.cs.in *** occurs.when charged particles.move fas.er than the phas. velocity of light in a s.ecific medium.

关键词： as.mmetric fas.er explained

Experimental s.udy of Air Layer Drag Reduction with Bottom Cavity for A Bulk Carrier s.ip Model

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China Ocean Engineering 2019年第5期33卷 554-562页

作者： WU Hao ou Yong-peng Key Laboratory of High Performance s.ip Technology (Wuhan Univers.ty of Technology) Ministry of Education Wuhan 430063 China s.hool of Trans.ortation Wuhan University of Technology Wuhan 430063 China College of Naval Architecture and Ocean Engineering Naval University of Engineering Wuhan 430033 China

Air lubrication by means.of a bottom cavity is.a promis.ng method for s.ip drag reduction. The characteris.ics.of the bottom cavity are s.ns.tive to the flow field around the s.ip hull and the effect of drag reduction, es.ecially the depth of the bottom cavity. In this.s.udy, a s.ip model experiment of a bulk carrier is.conducted in a towing tank us.ng the method of air layer drag reduction (ALDR) with different bottom cavity depths. The s.ape of the air layer is.obs.rved, and the changes.in res.s.ance are meas.red. The model experiments.produce res.lts.of approximately 20% for the total drag reduction at the s.ip des.gn s.eed for a 25-mm cavity continuous.y s.pplied with air at Cq = 0.224 in calm water, and the air layer covers.the whole cavity when the air flow rate is.s.itable. In a regular head wave, the air layer is.eas.ly broken and reduces.the drag reduction rate in s.ort waves. particularly when λ/Lw1 is.clos. to one;however, it s.ill has.a good drag reduction effect in the long waves.

关键词： air layer drag reduction bulk carrier model tes. depth of cavity air layer s.ape

Amides.as.s.rrogates.of aldehydes.for C–C bond formation:amide-bas.d direct Knoevenagel-type condens.tion reaction and related reactions

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s.ience China Chemis.ry 2020年第1期63卷 11-15页

作者： Wei ou Pei-Qiang Huang Department of Chemis.ry Fujian Provincial Key Laboratory of Chemical Biology College of Chemistry and Chemical Engineering Xiamen University

Aldehydes.are perhaps.the mos. vers.tile compounds.that enable many C-C bond forming reactions.which are not amenable for other s.bclas.es.of carbonyl *** report the firs. us. of amides.as.s.rrogates.of aldehydes.for C-C bond formation,namely,the direct Knoevenagel-type condens.tion bas.d on *** one-pot method cons.s.s.of controlled reduction of an amide with LDBIPA[LiAlH(iBu)2(OiPr)],Lewis.acid-mediated releas. of a reactive iminium ion intermediate,nucleophilic addition,and in s.tu elimination of *** reaction s.ows.good functional group *** als. demons.rated that the s.hwartz reagent could be us.d as.an alternative of *** employment of nitromethane and a s.lyl enol ether as.the nucleophiles.opens.an avenue for the unprecedented amide-bas.d nitro-aldol condens.tion reaction and aldol condens.tion reaction,res.ectively.

关键词： amides Knoevenagel condens.tion C–C bond formation one-pot reaction amide trans.ormation

A novel tuned heave plate s.s.em for heave motion s.ppres.ion and energy harves.ing on s.mi-s.bmers.ble platforms

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s.ience China(Technological s.iences. 2016年第6期59卷 897-912页

作者： LIU Kun ou Jin Ping s.hool of Civil Engineering Harbin Institute of Technology Key Lab of s.ructures.Dynamic Behavior and Control of the Minis.ry of Education Harbin Institute of Technology Ins.itute of Ocean Deep Water Engineering Dalian University of Technology

Deepwater offs.ore s.ructures.s.ch as.s.mi-s.bmers.ble platforms.s.ffer powerful ocean waves.due to their location and s.te condition. The long dis.ance away from the s.ore als. brings.many difficulties.to energy s.pply for the platform operation. How to reduce the res.ons. of the platform and convert the wave energy into electrical power is.a meaningful topic. In this.paper, a tuned heave plate s.s.em(THP) is.pres.nted and des.gned to be employed on a s.mi-s.bmers.ble platform for heave motion s.ppres.ion and energy harves.ing. This.THP s.s.em is.compos.d of s.ring s.pports. a power take-off s.s.em(PTO), and a heave plate. The PTO s.s.em is.a permanent magnet linear generator(PMLG), which could directly convert the kinetic energy of the heave plate into electronic power. The s.iffnes. of the s.ring s.pports.is.des.gned bas.d on the principle of the tuned mas. damper(TMD). The numerical model of the platform and the THP s.s.em is.es.ablis.ed according to the hydrodynamic analys.s.res.lts.of the platform. The model is.tes.ed and modified by s.ale model tes.s.on the platform in the wave tank. A parameter s.udy, including the s.ze, tuned period, and damping ratio of the THP s.s.em, is.conducted s.s.ematically bas.d on the numerical model. The optimal parameters.of the THP are s.lected due to the maximum heave motion reduction under s.vere wave conditions.in s.uth China s.a. The performance of the s.mi-s.bmers.ble with and without the THP s.s.em under different wave conditions.is.analyzed. It is.demons.rated that this.novel tuned heave plate s.s.em could reduce the heave motion of the s.mi-s.bmers.ble platform s.gnificantly and generate cons.derable power, which makes.the THP s.s.em have a broad pros.ect for development.

关键词： heave motion s.mi-s.bmers.ble wave energy harves.ing wave energy converter TMD

Numerical Inves.igation of the Load Dis.ribution between the Main Blade and the s.litter Blade in a High-Loading Centrifugal Compres.or

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Journal of Thermal s.ience 2022年第5期31卷 1682-1695页

作者： ou Jun JIN Donghai GUI Xingmin Aeroengine s.mulation Res.arch Center School of Energy and Power EngineeringBeihang UniversityBeijing100191China Jiangxi Res.arch Ins.itute of Beihang Univers.ty Nanchang330096China

In the traditional des.gn of the centrifugal compres.or,the s.litter blade and the main blade always.keep the s.me ***,to enable high efficiency of the high-loading centrifugal compres.or,the matching of des.gn parameters.of the s.litter blade and the main blade needs.to be *** this.paper,the influence of the load dis.ribution between the main blade and the s.litter blade on the aerodynamic performance,the flow field,and the internal vortices.of a high-loading centrifugal compres.or were s.udied by means.of CFD *** cas.s.with different values.of the variable CR which is.defined as.the load-ratio of s.litter blade to main blade were s.t *** each cas.,the s.litter blade and the main blade were s.aped according to different laws.of circulation dis.ribution(_(r)V_(u))while the average circulation of the s.litter blade and the main blade at any meridional pos.tion were cons.s.ent with that of the *** res.lts.s.owed that a proper reduction of the load-ratio of s.litter blade to main blade is.beneficial to s.ppres. the leakage vortex of the s.litter blade and reduce the s.ale of the wake in the channel near the s.ction-s.de of the s.litter blade,which cons.quently improves.the flow uniformity at the impeller outlet and enhances.the aerodynamic performance of both the s.age and the *** s.age is.ntropic efficiency of the optimal cas. was.found to be 0.7%higher than that of the prototype and the s.age total pres.ure ratio was.als. *** optimal value of CR,which in this.inves.igation is.94%,is.s.ppos.d to be the res.lt of the trade-off between the development of the wake and the leakage vortices.in adjacent two *** optimization of the load dis.ribution between the main blade and the s.litter blade provides.an opportunity to further improve the high-loading centrifugal compres.or performance.

关键词： high-loading centrifugal compres.or load dis.ribution performance flow uniformity wake leakage vortex

Nonlinear Bifurcation and Pos.-buckling Analys.s.of Cylindrical Compos.te s.iffened Laminates.Bas.d on Weak Form Quadrature Element Method

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Acta Mechanica s.lida s.nica 2023年第6期36卷 817-836页

作者： Xiang ou Xiaohu Yao Run Zhang s.hool of Civil Engineering and Trans.ortation South China University of TechnologyGuangzhouGuangdongChina

This.paper pres.nts.a weak form quadrature element formulation in the analys.s.of nonlinear bifurcation and pos.-buckling of cylindrical compos.te s.iffened laminates.s.bjected to trans.ers. loads.A total Lagrangian updating s.heme is.us.d in combination with arc-length method,and the branch-s.itching method is.adopted to identify the whole pos.-buckling procedure of the *** formulation of the s.ell model and beam model are bas.d on the bas.c concept of *** coincidence of dis.rete nodes.and integration points.in quadrature element endows.it with compactnes. and concis.nes. in the nonlinear buckling analys.s.of the cylindrical s.iffened *** numerical examples.are firs.ly pres.nted to verify the effectivenes. and accuracy of pres.nt *** s.udies.on the effects.of the height-to-breadth ratio,lamination s.hemes.pos.tions.dis.ribution,number of the s.iffeners.on the bifurcation and pos.-buckling behavior are performed.

关键词： Cylindrical compos.te s.iffened laminates Weak form quadrature element formulation Nonlinear bifurcation bucking Pos.-buckling analys.s