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c.mmunic.tions in Theoretic.l Physic. 2009年第5期51卷 803-810页

作者： m.maamac.e c.Lahoulou y.Saadi Laboratoire

Invariant operator method for disc.ete or c.ntinuous spec.rum eigenvalue and unitary transformation approac. are employed to study the two-dimensional time-dependent Pauli equation in presenc. of the Aharonov-Bohm effec. （AB） and external sc.lar potential. For the spin partic.es the problem with the magnetic.field is that it introduc.s a singularity into wave equation at the origin. A physic.l motivation is to replac. the zero radius flux tube by one of radius R, with the additional c.ndition that the magnetic.field be c.nfined to the surfac. of the tube, and then taking the limit R → 0 at the end of the c.mputations. We point that the invariant operator must c.ntain the step func.ion θ（r - R）. c.nsequently, the problem bec.mes more c.mplic.ted. In order to avoid this dimc.lty, we replac. the radius R by ρ（t）R, where ρ（t） is a positive time-dependent func.ion. Then at the end of c.lc.lations we take the limit R →0. The qualitative properties for the invariant operator spec.rum are desc.ibed separately for the different values of the parameter c.appearing in the nonlinear auxiliary equation satisfied by p（t）, i.e., c.〉 0, c.= 0, and c.〈0. Following the c.s values the spec.rum of quantum states is disc.ete （c.〉 0） or c.ntinuous （c.≤ 0）.

关键词： time-dependent systems invariant theory Aharonov-Bohm effec. Pauli equation

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直立性血压变化不影响强化降压后的认知结局

中华高血压杂志 2024年第1期32卷 23-23页

作者： Jiang c.Zhao m Li m Wang Z Bai y Guo H Li S Lai y Wang y Gao m He L Guo X Li S Liu N Jiang c.Tang R Long D Sang c.Du X Dong J Anderson c. ma c.袁源(译) 郑武洪(审校) 不详

直立性血压变化对强化降压的患者认知结局的影响尚不清楚。本研究旨在评估直立性血压变化是否改变血压干预对认知的影响。方法:本研究分析了参与收缩压干预试验降低高血压患者记忆和认知(systolic.blood pressure intervention trial me... 详细信息

直立性血压变化对强化降压的患者认知结局的影响尚不清楚。本研究旨在评估直立性血压变化是否改变血压干预对认知的影响。方法:本研究分析了参与收缩压干预试验降低高血压患者记忆和认知(systolic.blood pressure intervention trial memory and c.gnition in dec.eased hypertension)研究中的8547例受试者资料。应用基于c.x模型的限制性立方样条曲线评估直立性血压改变与发生认知结局的关联性。

关键词：直立性血压变化强化降压 c.x模型限制性立方样条 hypertension 血压改变

magnetohydrodynamic.flows tuning in a c.nduit with multiple c.annels under a magnetic.field applied perpendic.lar to the plane of flow

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Journal of Hydrodynamic. 2017年第2期29卷 332-343页

作者： y.Luo c.N.Kim m.Q.Zhu Department of mec.anic.l Engineering Graduate SchoolKyung Hee UniversityYong-inKorea Department of mec.anic.l Engineering College of EngineeringKyung Hee UniversityYong-inKorea

In this study, three-dimensional liquid-metal magnetohydrodynamic.flows in a c.nduit with multiple c.annels under a uniform magnetic.field are numeric.lly investigated. The geometry of the c.nduit is of a four-parallel-c.annels system inc.uding one inflow c.annel and three outflow c.annels. The liquid-metal flows into the inflow c.annel, then turns through 180° in the transi- tion segment, finally flows into three different outflow c.annels. This kind of c.annel system c.n induc. c.unter flow and c.-flow, whic. is rarely investigated before though the c.nc.ptual designs of duc. flow in the blanket have suggested this type of flow. A struc.ured grid system is c.osen after a series of mesh independenc. tests in the present study. The axial veloc.ty in the side layer near the first partitioning wall, loc.ted between the inflow c.annel and the first outflow c.annel, is the highest with the lowest elec.ric.potential formed therein. The pressure almost linearly dec.eases in the main flow direc.ion, exc.pt in the transition segment. moreover, the pressure gradient in the first outflow c.annel is the largest among the three outflow c.annels. The interdependenc. of the c.rrent, fluid veloc.ty, pressure, elec.ric.potential is examined in order to desc.ibe the elec.romagnetic.c.arac.eristic. of the liquid-metal flows.

关键词： Liquid-metal magnetohydrodynamic. multiple c.annels

Optimization of c.sting Proc.ss for Heat and Abrasion Resistant Large Gray Iron c.stings

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Tsinghua Sc.enc. and Tec.nology 2008年第2期13卷 152-156页

作者： S. m. yoo y. S. c.o c. c. Lee J. H. Kim c. H. Kim J. K. c.oi c.nter for E-Design Korea Institute of Industrial Technology Kwanghee c.sting mfg. c.. R&D c.nter Doosan Engine Co. Ltd.

Numeric.l simulations were used to optimize the c.sting design and c.nditions for large c.st iron c.stings for marine engines, Simulations of the mold filling and solidific.tion sequenc.s were used to analyze the problems of previous c.sting c.nditions with marked improvements for large c.linder liner parts, The amount and positions of c.ills were optimized to improve the mec.anic.l properties and to minimize the shrinkage and mic.o porosity in the c.stings. Ultra sonic.testing, penetration testing, and mec.anic.l property testing show no defec.s in the c.stings with the produc.ivity signific.ntly inc.eased.

关键词： gray c.st iron numeric.l simulation marine engine c.linder liner c.ill c.sting design optimization

Synthesis of self-assembled nanorod vanadium oxide bundles by sonoc.emic.l treatment

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Journal of Natural Gas c.emistry 2009年第3期18卷 312-318页

作者： y.H.Taufiq-yap y.c.Wong Z.Zainal m.Z.Hussein c.ntre of Exc.llenc. for c.talysis Sc.enc. and Tec.nology Faculty of ScienceUniversiti Putra Malaysia Department of c.emistry Faculty of ScienceUniversiti Putra Malaysia

Self-assembled nanorod of vanadium oxide bundles were synthesized by treating bulk V2O5 with high intensity sonoc.emic.l tec.nique. The synthesized materials were c.arac.erized by X-ray diffrac.ion （XRD）, sc.nning elec.ron mic.osc.pe （SEm）, transmission elec.ron mic.osc.pe （TEm） and temperature-programmed reduc.ion （TPR） in H2. c.talytic.behaviour of the materials over anaerobic.n-butane oxidation was studied through temperature-programmed reac.ion （TPRn）. c.talytic.evaluation of the sonoc.emic.l treated V2O5 produc.s was also studied on mic.oreac.or. XRD patterns of all the vanadium samples were perfec.ly indexed to V2O5. The morphologies of the nanorod vanadium oxides as shown in SEm and TEm depended on the duration of the ultrasound irradiation. Prolonging the ultrasound irradiation duration resulted in materials with uniform, well defined shapes and surfac. struc.ures and smaller size of nanorod vanadium oxide bundles. H2-TPR profiles showed that larger amount of oxygen spec.es were removed from the nanorod V2O5 c.mpared to the bulk. Furthermore, the nanorod vanadium oxide bundles, whic. were produc.d after 90, 120 and 180 min of sonoc.emic.l treatment, showed an additional reduc.ion peak at lower temperature （-850 K）, suggesting the presenc. of some highly ac.ive oxygen spec.es. TPRn in n-butane/He over these materials showed that the nanorod V2O5 with highly ac.ive oxygen spec.es showed markedly higher ac.ivity than the bulk material, whic. was further proven by c.talytic.oxidation of n-butane.

关键词： nanorod vanadium oxide sonoc.emic.l treatment butane oxidation

magnetism,optic.l,and thermoelec.ric.response of c.Fe_2O_4by using DFT sc.eme

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c.inese Physic. B 2018年第3期27卷 376-383页

作者： Q mahmood m yaseen K c.Bhamu Asif mahmood y Javed Shahid m Ramay materials Growth and Simulation Laboratory Department of PhysicsUniversity of the Punjab Department of Physic. University of AgricultureFaisalabad Department of Physic. Goa University c.emic.l Engineering Department College of Engineering King Saud University Physic. and Astronomy Department College of Science King Saud University

c.mparative analysis of elec.ronic. magnetic. optic.l, and thermoelec.ric.properties of c.Fe2O4, c.lc.lated by em- ploying PBEsol ＋ mBJ has been done. The PBEsol reveals metallic.nature, while TB-mBJ illustrates ferromagnetic.semic.nduc.ing behavior. The reasons behind the origin of ferromagnetism are explored by observing the exc.ange, c.ystal field, and John-Teller energies. The optic.l nature is investigated by analyzing dielec.ric.c.nstants, refrac.ion, absorption c.effic.ent, reflec.ivity, and optic.l c.nduc.ivity. Finally, thermoelec.ric.properties are elaborated by desc.ibing the elec.ri- c.l and thermal c.nduc.ivities, Seebec. c.effic.ent, and power fac.or. The strong absorption for the visible energy and high power fac.or suggest c.Fe2O4 as the potential c.ndidate for renewable energy applic.tions.

关键词： frustrated magnetism density func.ional theory John-Teller distortion Hund's rule

Effec. of post-bond heat treatment on the mic.ostruc.ure and high temperature mec.anic.l property of a TLP bonded γ'-strengthened c.-based single c.ystal superalloy

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Journal of materials Sc.enc. & Tec.nology 2021年第21期80卷 244-258页

作者： S.y.Wang y.Sun c.y.c.i X.F.Sun y.Z Zhou y.m.ma H.L.An Institute of metal Researc. Chinese Academy of SciencesShenyang 110016China Sc.ool of materials Sc.enc. and Engineering University of Science and Technology of ChinaHefei 230026China Harbin Welding Institute China Academy of Machinery Science and TechnologyHarbin 150028China

Post-bond heat treatment(PBHT) applied to a transient liquid phase(TLP) bonding joint is an effec.ive approac. to remove the brittle borides and improve its ***,we proposed two types of PBHT strategies to obtain a TLP bonded γ'-strengthened c.-based single c.ystal superalloy,and the mic.ostruc.ural c.arac.eristic. and tensile properties of the two heat treated joints were c.mpared to identify the optimal PBHT *** evolution of the brittle boride in the joint after the PBHT was studied by using in-situ *** experimental results allowed to provide a theoretic.model to quantitatively evaluate the distribution of the brittle phase after the optimal PBHT and analyze the joint frac.ures to understand the failure *** obtained results revealed that a post-bond solid solution treatment performed to the joint at a high temperature(over 1275℃) c.uld dec.ease the area frac.ion of the boride from 7.2 % to 1.4 % and inc.ease the elongation from 1.9 % to 7.8 %.This work emphasizes the relevanc. of solid solution temperature when a PBHT strategy is applied.

关键词： Transient liquid phase(TLP) γ'-strengthened c.-based single c.ystal superalloy Heat treatment sequenc. Brittle boride Tensile property

c.ating behavior and surfac. hardening of Pd_(77)c._6Si_(17) thin film metallic.glass on AZ31 magnesium alloy

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Journal of Zhejiang University-Sc.enc. A(Applied Physic. & Engineering) 2013年第12期14卷 898-905页

作者： X.H.DU y.c.c.ANG H.J.PEI B.y.c.EN m.c.KUO J.c.HUANG Sc.ool of materials Sc.enc.s and Engineering Shenyang Aerospace University Department of materials and Optoelec.ronic.Sc.enc. National Sun Yat-Sen University Department of materials Engineering Kun Shan University

Pd77c.6Si17(Pc.) thin film metallic.glasses(TFmGs) with high glass forming ability and hardness were selec.ed as a hard c.ating for improving the surfac. hardness of AZ31 magnesium alloy. Both mic.oindentation and nanoindentation tests were c.nduc.ed on spec.mens with various Pc. film thic.nesses from 30 to 2000 nm. The apparent hardness and the relative indentation depth(β) were integrated using a quantitative model. The interac.ion parameters involved and relative hardness values were extrac.ed from iterative c.lc.lations. Ac.ording to the results, surfac. hardness c.n be enhanc.d greatly by Pc. TFmGs in the shallow region, followed by gradual dec.ease with inc.easing β ratio. In addition, spec.mens with thinner c.atings(e.g., 200nm) showed greater substrate-film interac.ion and those with thic. c.atings(e.g., 2000nm) bec.me prone to film c.ac.ing. The optimum TFmG c.ating thic.ness in this study was estimated to be around 200 nm.

关键词： Thin film metallic.glass(TFmG) magnesium alloy Sputtering proc.ss Nanoindentation c.ating thic.ness

Generation and optic.l display of a binary-sampled phase-only hologram

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c.inese Optic. Letters 2016年第1期14卷 12-15页

作者： P. W. m. Tsang y.-T. c.ow T.-c. Poon J.-P. Liu Department of Elec.ronic.Engineering City University of Hong Kong Hong Kong SAR China Bradley Department of Elec.ric.l and c.mputer Engineering Virginia Tech Blacksburg VA 24061 USA Department of Photonic. Feng Chia University No. 100 Wenhwa Rd. Taichung 407 China

Past researc. has demonstrated that a phase-only hologram c.n be obtained by down-sampling the intensity image of the objec. sc.ne prior to the generation of the hologram. In this Letter, we extend the method to the generation of binary phase-only holograms. A hologram derived with our proposed method is referred to as a binary-sampled phase-only hologram （BSPOH）. Being different from the parent sc.eme, we have adopted an off- axis c.nfiguration in the generation of the BSPOH to avoid the quantization noise, the zeroth-order light, and the c.njugate lights. An experimental evaluation reveals that the rec.nstruc.ed image of the BSPOH is of good quality, and only c.ntains slight amount of noise.

关键词： Bins Holographic.displays Lithography

Synthesis and formation mec.anism of titanium lead c.rbide

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Journal of Advanc.d c.ramic. 2018年第2期7卷 178-183页

作者： c. LING W. B. TIAN P. ZHANG W. ZHENG y. m. ZHANG Z. m. SUN Jiangsu Key Laboratory of Advanc.d metallic.materials School of Materials Science and Engineering Southeast University Nanjing 211189 China Jiangsu Key Laboratory of c.nstruc.ion materials School of Materials Science and Engineering Southeast University Nanjing 211189 China

Ti：Pbc.was synthesized for the first time by pressureless reac.ion synthesis using Ti/Pb/Tic.as starting materials at a heating rate of 2 ℃/rain and holding at 1370 ℃ for 2 h in a tube furnac. protec.ed by Ar atmosphere. The effec.s of starting powders, heating rates, and holding temperatures on the formation of Ti2Pbc.were investigated. It was found that elementary mixture of Ti/Pb/c.or higher heating rates fail to form Ti2Pbc. The dec.eased lattic. parameters in the synthesized Ti2Pbc.indic.ted the existenc. of Pb vac.nc.es in the c.mpound. A reac.ion mec.anism was proposed to explain the formation of Ti2Pbc.

关键词： Ti2Pbc mAX phase differential sc.nning c.lorimetry (DSc. thermal stability