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OXIdATION Of.A TWO-PHASE cu-75cr ALLOy IN AIRAT 700-900℃

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 333-341页

作者： f. Gesmundo y Niu f. Vianiand d.L. douglass(Universita di Genova, f.era del Mare, Pad. d,16129 Genova, Italy)(State Key Lab. f.r corrosion and Protection, Institute of.corrosion and Protection of.Metals, thechinese Academy of.Sciences, Shenyang 110015, ch Univ di Genova Genova Italy

The cormsion in air of.a two-phase cu-75cr alloy was studied at 700-900℃. Thealloy cormded nearly parabolically at 700-800℃, but at 900℃ its instantaneousparabolic mte constant decreased with time. The scales were complex and consistedof.an outermost layer of.copper oxide generally f.llowed bg a layer of.the double ox-ide cu2 cr2 O4 sometimes containing particles of.unoxidized chromium surmunded bya chromia layer. An innermost layer of.chromia was also observed in some *** metallic copper was al8o f.equently mixed with chromia particles. No cr de-pletion was observed in the alloy close to the intef.oce with the scale. In any case,this alloy was not able to f.rm an exclusive continuous protective chromia layer. Thespecial cormsion behavior Of.this alloy is typical of.two-phase binary systems with alange solubility gaP in which the outwaof.dthesion f.ux of.the most-reactive componentin the alloy is strongly reduced and may be inswncient to f.rm a protective externallayer of.the cormsponding oxide. In paTticular, the presence of.particles of.cr withina double oxide layer is very unusual and is allowed only f.r the kinetic reason.

关键词： copper-chromium alloy two-phase oxidation

Ef.ect of.2–6 at.% Mo addition on microstructural evolution of.Ti-44Al alloy

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Journal of.Materials Science & Technology 2018年第7期34卷 1196-1204页

作者： S.Z.Zhang Z.W.Song J.c.Han c.J.Zhang P.Lin d.d.Zhu f.T.Kong y.y.chen School of.Materials Science and Engineering Taiyuan University of Technology Shanxi Key Laboratory of.Advanced Magnesium-Based Materials Taiyuan University of Technology School of.Mechanical Engineering Taiyuan University of Technology School of.Mechanical Engineering Quzhou University State Key Laboratory f.r Advanced Welding and Jointing Harbin Institute of Technology

In order to understand the ef.ect of.Mo alloying on the microstructural evolution of.TiAl alloy, the as-cast microstructure, heat treated microstructure characteristic, and hot compression microstructure evolution of.Ti-44Al alloy have been studied in this work. The as-cast microstructure morphology changes f.om （γ＋α2） lamellar colony and β/β0＋γ mixture structure to β/β0 phase matrix widmannstatten structure, when Mo content increases f.om 2 at.% to 6 at.%. Af.ected by the relationship between β phase and α90℃phase, the angles between the lamellar orientation and the block β/β0 phase are roughly at 0℃, 45℃ and 90℃. comparing with heat treatment microstructure, the hot compression microstructure contains less β/β0 phase, however, theβ/β0 phase containing 2Mo alloy and 3Mo alloy hot compressed at 1275 ℃ has the inverse tendency. In addition, （α2 ＋γ） colony is decomposed by the discontinuous transf.rmation.2017 Published by Elsevier Ltd on behalf.of.The editorial of.ice of.Journal of.Materials Science ＆ Technology.

关键词： Phase transf.rmation Titanium aluminides Heat treatment Microstructure evolution,β/βo phase

A new beam asymmetry measurement f.om pion photoproduction on the neutron using cLAS

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chinese Physics c 2009年第12期33卷 1369-1372页

作者： d. Sokhan d. Watts f. Klein School of.Physics & Astronomy University of Edinburgh Edinburgh EH9 3JZ UK department of.Physics Catholic University of America Washington DC 20064 USA

We present a preliminary analysis of.the photon beam asymmetry observable （Z） f.om the pho- toproduction reaction channel γn → pπ in the invariant mass range 1.6--2.3 GeV. The measurement was obtained using the near-4π cEBAf.Large Acceptance Spectrometer （cLAS） at Jef.erson Laboratory, USA, employing a linearly polarised photon beam with an energy range 1.1 2.3 GeV, incident on a liquid deuterium target. The measurement will provide new data to address the poorly established neutron excitation spectrum and will greatly expand the sparse world data-set both in energy and angle.

关键词： beam asymmetry photonuclear photoproduction neutron pion.

HydROGEN Ef.EcT ON dEf.RMATION BEHMIOR Of.TITANIUM ALLOy AT HIGH TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 1998年第3期11卷 190-196页

作者： c.H.Zhou K.yang d.f.Li y.X.Lu Inst of.Metal Research The Chinese Acad of Sciences Shenyang China

The ef.ect of.hydrogen on the def.rmation behavior of.three typical kinds of.titanium alloys, pure Ti, Ti-6Al-4V and Ti-15V-3cr-3Al-3Sn (Ti-15-3), at high temperature has been investigated by short time creep test. XRd and TEM techniques are used to examine the changes in their microstructures. The results show that def.rmation rutes of.pure Ti and Ti-6Al-4V alloy can be greatly increased by hydorgen charping due to an increase of.β phase volume in their microstructures. β→α transf.rmation is f.und to occur in unchanged Ti-15-3 alloy during creep process. The addition of.0. 73wt% hydrogen can completely inhibit the def.rmation-induced transf.rmation and strengthen the metastable β phase in Ti-15-3 alloy, resulting in a dramatic decrease of.def.rmation rate of.this alloy at 700° c.

关键词： titanium hydrogen thermal def.rmation

STUdy ON REdUcING THE cORE LOSS Of.GRAIN ORIENTEd SILIcON STEEL ANd IMPROVING ITS AGING PROPERTy By LASER NITRIdING TEcHNIQUE IN ATMOSPHERIc AMBIENT

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 533-538页

作者： y.L. yang c.S. Liu f.J. Sun d. Zhang college of.Science Northeastern University Shenyang 110004 China college of.Material ＆ Metallurgy Northeastern University Shenyang 110004China

cW-cO2 laser nitriding technique was applied to improve the properties （such as aging property and the core loss） of.grain oriented silicon steel. The samples were nitrided with regular space. Laser power density and scanning speed were chosen as 7.8×10^5W·cm^-2 and 100mm·min^-1. By some laser irradiation, f.4N and f.3N were f.rmed in the nitrided zone. The nitrided samples were annealed at the temperatures ranged f.om 100 to 90℃. The core loss of.some interested samples was tested. The results show that the core loss of.the nitrided samples with dif.erent thickness of.0.23 and 0.30mm decreased by 14.9% and 9.4% respectively, and the aging property were improved up to 800℃. The mechanism of.laser nitriding to improve the properties of.grain oriented silicon steel is discussed.

关键词： laser nitriding grain oriented silicon steel sheet core loss aging property

Synthesis and characterization of.Tb-incorporated Apatite Nano-scale Powders

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Journal of.Materials Science & Technology 2012年第9期28卷 773-778页

作者： L.J. Sun P.f. Ni d.G. Guo c.Q. f.ng J. Wang f. yang X.f. Huang y.Z. Hao H. Zhu K.W. Xu State Key Laboratory f.r Mechanical Behavior of.Materials School of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 China School of.Printing and Packaging Engineering Xi'an University of Technology Xi'an 710048 China Xi'an University of.Arts and Science Xi'an 710065 China

Nano-scale Tb-incorporated apatite （nano-Tb-AP） particles with dif.erent Tb contents （Tb/（Tb＋ca）） of.0%, 5%, 10% and 20% were synthesized through a simple wet chemical method in this study. The crystal structure, thermal stabilities, chemical groups, crystal morphologies and.c.ystal sizes of.the nano--Tb-AP particles were characterized by X-ray dif.raction （XRd）, f.urier transf.rm inf.ared spectroscopy （f.IR）, and transmission electron microscopy （TEM）, respectively. It was f.und that lattice constants, particle sizes, crystalline and thermal stability varied with the doped Tb contents. With the increasing of.Tb content, the lattice constants, particle size, length/diameter ratio, crystalline and thermal stability of.nano-Tb-AP gradually decrease. Especially, almost all the 20%Tb-AP nano particles had been decomposed at 1200 ℃ while only a f.w of.the decomposed products （β-TcP） were detected in the Tb-f.ee nano apatite powders： This kind of.nano-scale Tb-incorporated apatite exhibits an extremely potential clinic application because it integrates both the excellent biological f.nctions of.Tb element and apatite in human body.

关键词： Nano-scale powder Terbium (Tb) Wet chemical approach Apatite Biomedical materials

Modelling and mapping third dimension in a spatial database

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International Journal of.digital Earth 2011年第6期4卷 505-520页

作者： f.donera c.Bıyık department of.Geomatics Engineering Gumushane UniversityGumushaneTurkey department of.Geomatics Engineering Karadeniz Technical UniversityTrabzonTurkey

In this paper,an overview of.phases f.r modelling and mapping third dimension of.spatial objects in a database is presented based on a selected spatial database management system(dBMS).These phases include(1)def.ning a spatial ref.rence system f.r representing three-dimensional(3d)objects with real-world coordinates,(2)geometric modelling of.3d objects in the database,(3)3d spatial indexing f.r f.st accessing/querying the 3d data,3d spatial queries and representation of.3d ***,a case study is perf.rmed to assess needs,possibilities and potential limitations of.3d data modelling in the spatial database.

关键词： spatial database geo-data 3d data modelling GIS digital earth

Accuracy details in realistic cf. modeling of.an industrial centrif.gal pump in direct and reverse modes

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Journal of.Thermal Science 2010年第6期19卷 491-499页

作者： J.c. Páscoa f. J. Silva J.S. Pinheiro d.J. Martins department of.Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior Ef.f.U Bombas e Ventiladores S.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of.the f.owf.eld inside a pump is herein used as a numerical laboratory, subject to the limitations of.modeling assumptions and to experimental verif.cation. A numerical computation of.the f.ow inside a real industrial centrif.gal pump is perf.rmed that includes a very sophisticated geometry. conversely to other computations, in this test case no simplif.cation of.the geometry was introduced. Numerical computations are obtained using Spalart-Allmaras turbulence model. A detailed analysis of.the turbulent f.owstructure is perf.rmed f.r the design point and two of. design conditions. Additional computations were perf.rmed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. f.rther computations are presented f.r the pump working in reverse turbine mode (PAT). detailed analyses of.the f.ow allow a comparison of.the internal f.ow losses when the pump is operating in direct and reverse mode. This is also usef.l to help in the selection of.an adequate pump geometry that can work in both modes with best ef.iciency.

关键词： centrif.gal pump impeller turbulence modeling Spalart-Allmaras PAT

STRUcTURE ANd BINdING STATE Of.cN_x f.LMS SyNTHESIZEd By f.cING TARGETS SPUTTERING

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 752-756页

作者： Tang, d.Q. Wang, y. Jiang, E.y. Zhao, c. Sun, f.L. Tianjin Univ Tianjin China

cN x f.lms were made by a f.cing targets sputtering ( f.S) systemon the  Si(100) substrate under dif.erent  N 2 partial pressure.  XRd, XPS, f.IR and Raman Spectroscopy( RS) were measured to investigate the structure and the binding state of.the f.lm. The f.lms are amorphous and the  N/c increases with the  N 2 partial pressure increasing and reaches 0 46 when the  N 2 pressure is 100%. The N incorporated  c f.rms N sp 2c and N sp 3c mainly and there is a small amount of. c≡N.

关键词： Amorphous f.lms Hard disk storage Hardness Nitrides Silicon waf.rs Sputtering Synthesis (chemical)