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Interface effect on the giant magnetoresistance for different magnetic multilayers systems

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Chinese Science Bulletin 1997年第9期42卷 729-733页

作者： Zhang, LY sun, h Li, BZ Pu, FK Institute of Physics Chinese Academy of Sciences Beijing China State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China

ThE giant magnetoresistance(GMR)effect in magnetic multilayer has been the subject of in-tense investigation since its *** theories,including semiclassical theoryand quantum theory,have been developed to deal with the... 详细信息

关键词： magnetic multilayer interface effect giant magnetoresistance Anderson model.

Microstructure change in Fe-based metallic glass and nanocrystalline alloy induced by liquid nitrogen treatment

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Journal of Materials Science & Technology 2021年第10期69卷 1-6页

作者： M.C.Ri D.W.Ding Y.h.sun W.h.Wang Institute of Physics Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory Dongguan523808China

The effects of acyclic liquid nitrogen(LN)treatment in a temperature range of-196℃to 50℃on the thermal and magnetic stability of Fe78Si9B13 and Fe73.5Si13.5B9Nb3Cu1 glassy ribbons have been *** intrinsic heterogeneities of the metallic glasses can be activated through cryogenic thermal cycling,making irreversible structural changes after the treatment and inducing rejuvenation to the *** microstructural changes of both Fe-based metallic glass(MG)and nanocrystalline alloy induced by LN treatment were *** experimental results show that the LN treatment could effectively rejuvenate the Fe-Si-B MGs and change their thermomechanical and magnetic *** on the partially-crystallinity and well-known magnetic constants,the increase of the energy at the order of 10m J/g and magnetic domain wall movement and rotation at the order of 5-6μm and 0.5°-0.8°are found for FINEMET-type amorphous alloy after LN *** is also found that LN treatment can contribute a little stored energy to the magnetic domain wall movement and magnetic domain rotation.

关键词： Metallic glasses Cryogenic thermal treatment Soft magnetic materials Rejuvenation Stored energy Domain wall

A continuum traffic flow model with the consideration of coupling effect for two-lane freeways

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Acta Mechanica Sinica 2011年第2期27卷 228-236页

作者： D.-h. sun G.-h. Peng L.-P. Fu h.-P. he College of Automation Chongqing University400030 Chongqing China Department of Civil & Environmental Engineering University of Waterloo Waterloo Ontario N2L 3G 1 Canada College of Automation Chongqing University 400030 Chongqing China

A new higher-order continuum model is proposed by considering the coupling and lane changing effects of the vehicles on two adjacent lanes. A stability analysis of the proposed model provides the conditions that ensure its linear stability. Issues related to lane changing, shock waves and rarefaction waves, local clustering and phase transition are also investigated with numerical experiments. The simulation results show that the proposed model is capable of providing explanations to some particular traffic phenomena commonly observable in real traffic flows.

关键词： Two-lane traffic Two delay time scales model Numerical simulation Coupling effect Phase transition

Rotational and translational domains of beta precipitate in aged binary Mg-Ce alloys

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Journal of Magnesium and Alloys 2021年第3期9卷 1039-1056页

作者： B.Z.sun h.X.Zhang Y.Dong J.X.Ren Y.Tian G.M.Xie J.Tan Y.h.sun Na Xiao School of Materials Science and Engineering Northeastern UniversityShenyang 110819China State Key Lab Rolling&Automat Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Analytical and Testing Center Northeastern UniversityShenyang 110819China

The structural evolution fromβ_(1)(Mg_(3)Ce)toβ(Mg_(12)Ce)precipitates,which takes place at the over-aged stage of binary Mg-Ce alloys,are investigated by high-angle annular dark-field scanning transmission electron *** structural transformation mainly occurs in the{111}_(β1)crystallographic planes,where the newly formedβlattices exhibit two categories of domain structures,namely rotational and translational *** rotational domain is composed of threeβdomains(β_(RA),β_(RB)andβ_(RC)),which are related by a 120°rotation with respect to each other around the 111_(β1)axis of theirβ_(1)parent ***{111}_(β1)crystallographic planes can provide four sets of sublattices with the same orientation for an initial nucleation ofβ*** leads to the formation of four translationalβdomains(β_(TA),β_(TB),β_(TC)andβ_(TD)),among which any two differ by a vector of 1/6112_(β1).We deduce theoretically that there exist twenty-fourβdomains during this ***,considering the interfacial misfit,only one-third of domains can grow up and eventually formsβ***,a majority ofβribbons overlap partiallyβ_(1)plate,which is beneficial to relax interfacial strain amongβ,β_(1)andα-Mg matrix(α/β/β_(1)).The configuration of multipleβdomains can effectively regulate interfacial misfit ofα/βandβ/β_(1),which are responsible for enhancing the hardness and strength of Mg-Ce ***,this study aims to provide some clues to improve the over-aged performance of magnesium alloys by constructingβdomains and optimizing theα/β/β_(1)interface.

关键词： Magnesium alloys hAADF-STEM Rotational domain Translational domain Phase transition Interfacial misfit

Local Convective heat Transfer from Small heaters to Impinging Submerged Axisymmetric Jets of Seven Coolants with Prandtl Number Ranging from 0.7 to 348

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Journal of Thermal Science 1997年第4期6卷 286-297页

作者： h.sun C.F.Ma 等 DepartmentofThermalScience＆Engineering BeijingPolytechnicUniversityBeijing100022China DepartmentofT

Using seven working fluids, a systematic experimental study was performed to investigate the local convective heat transfer from vertical heaters to impinging circular submerged jets in the range of Reynolds number between 1.17 ×102 and 3.69 × 104 with the emphasis placed on the examination of Prandtl number dependence. heat transfer coefficiellts at the stagnation point were collected and correlated with the plate held within and beyond the potential core. Radial distribution of the local heat transfer coefficient was measured with five test liquids. Based on the measured profiles of the local heat transfer, a correlation was developed to cover the entire range of the radial distance. Besides the presellt data, the correlations developed in this work were also compared with a large quantity of available data of circular air jets. General agreement was observed between the air data and the correlat ions.

关键词： forced convection jets Prandtl number

Improvement of Coercivity and Corrosion Resistance of Nd-Fe-B Sintered Magnets with Cu Nano-particles Doping

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Journal of Materials Science & Technology 2012年第10期28卷 927-930页

作者： C.sun W.Q.Liu h.sun M.Yue X.F.Yi J.W.Chen College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China Earth-panda Advance Magnetic Material Co. Ltd.Anhui 231500China

Nd-Fe-B permanent magnets with a small amount of Cu nano-particles doping have been prepared by con-ventional sintered method. Effects of Cu content on magnetic properties, corrosion resistance, and oxidation properties of the magnets have been studied. It shows that the coercivity rises gradually, while the remanence decreases simultaneously with increasing Cu doping amount. Microstructure observation reveals that Cu ele- ment enriches mainly the Nd-rich phase. Autoclave test results show that the corrosion rate of the magnets decreases with increasing Cu content. After oxidation, the maximum energy product loss of the magnets with 0 and 0.2 wt% Cu nano-particles doping are 6.13% and 0.g9%, respectively. Therefore, it is concluded that Cu nano-particles doping is a promising way to enhance the coercivity and corrosion resistance of sintered Nd-Fe-B magnets.

关键词： Nd-Fe-B Cu nano-particles Coercivity Corrosion resistance Oxidation

Toward precision mass measurements of neutron-rich nuclei relevant to r-process nucleosynthesis

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Frontiers of physics 2015年第4期10卷 1-25页

作者： B. h. sun Yu. A. Litvinov I. Tanihata Y. h. Zhang School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China International Research Center for Nuclei and Particles in the Cosmos Beijing 100191 China Key Laboratory of high Precision Nuclear Spectroscopy and Center for Nuclear Matter Science Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China GSI helmholtzzentrum fiir Schwerionenforschung Planckstrafle 1 64291 Darmstadt Germany

The open question of where, when, and how the heavy elements beyond iron enrich our Universe has triggered a new era in nuclear physics studies. Of all the relevant nuclear physics inputs, the mass of very neutron-rich nuclides is a key quantity for revealing the origin of heavy elements beyond iron. Although the precise determination of this property is a great challenge, enormous progress has been made in recent decades, and it has contributed significantly to both nuclear structure and astrophysical nucleosynthesis studies. In this review, we first survey our present knowledge of the nuclear mass surface, emphasizing the importance of nuclear mass precision in r-process calculations. We then discuss recent progress in various methods of nuclear mass measurement with a few selected examples. For each method, we focus on recent breakthroughs and discuss possible ways of improving the weighing of r-process nuclides.

关键词： binding energy r-process nucleosynthesis nuclear mass spectrometry

Research on high-Speed Drilling Performances of Austenitic Stainless Steels

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上海交通大学学报 2004年第z2期38卷 83-88页

作者： J.W.Zhong Y.P.Ma F.h.sun M.Chen School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030China

Due to specific properties arising from their structure (high ductility, high toughness,strong tenacious and low heat conductivity), the stainless steels have poor machinability. The drilling of the stainless steels becomes the machining difficulty for their serious work-hardening and abrasion of tools. In this paper, the austenitic stainless steel is used as the work-piece to perform the contrastive experiments with the TiN coated and TiAlN-coated high-speed steel drills. The cutting force, torque, cutting temperature, and the abrasion of drills and tool life are tested and analyzed in the process of high-speed drilling. Experiment results show the effect of drilling speed on cutting force, cutting temperature, and drill wear. TiAlN-coated drills demonstrate better performances in high speed drilling. The research results will be of great benefit in the selection of drills and in the control of tool wear in high speed drilling of stainless steels.

关键词： stainless steel TiN-coating TiAlN-coating drilling

IMPROVED METhOD OF PARTIAL SIMILARITY OF BOUNDARY LAYER ALONG CURVED SURFACE

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Journal of hydrodynamics 2001年第2期13卷 77-79页

作者： sun, F.Z. Shi, Y.T. sun, h.J. Ping, Y.M. Zhang, M.Y. Inst. of Energy and Power Shandong Univ. Jinan 250061 China

The solution of boundary layer along a curved surface was discussed in this article. According to the principle of the theory of similarity, the method of partial similarity was proposed, in which the profile of object is divided into many tiny sections, the method of similarity was used in each section and the error in each section was fully considered. This method is proved to be feasible.

关键词： Cylinders (shapes) Differential equations Error analysis Surfaces