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Th. dependence of th. parallel and perpendicular mean free path. on th. rigidity of th. solar energetic particles:Th.oretical model versus observations

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The dependence of the parallel and perpendicular mean free p...

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： h.-q.he W.Wan Key Laboratory of Ionosph.ric Environment Institute of Geology and GeophysicsChinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of Sciences

*** dependence of th. parallel and perpendicular mean free path. on th. particle rigidity is an important topic in th. studies of th. diffusion and propagation of ch.rged energetic particles in a large-scale turbulent magnetic field. *** th.s work,we investigate th. dependence of th. parallel and perpendicular mean free path. on th. rigidity of solar energetic particles(SEPs) by means of both.th. th.oretical model and spacecraft observations with.regard to several typical SEP events. Meth.ds.A direct meth.d developed by previous studies and derived from th. focused transport equation and Taylor-Green-Kubo (TGK) formulation is applied to explicitly determine th. parallel and perpendicular mean free path. of SEPs in a turbulent and spatially varying magnetic field. *** find th.t th. parallel and perpendicular mean free path.,λ andλ,of energetic protons monotonically decrease with.increasing particle rigidity,and th. ratioλ/λmonotonically increases with.particle rigidity,wh.n th. magnetic turbulence is weak. Taking a series of typical SEP events togeth.r,it can also be seen th.t th. ratioλ⊥/λof th. perpendicular to th. parallel mean free path. remains in th. range of 0.001-0.2.

关键词： interplanetary medium magnetic fields solar terrestrial relations Sun coronal mass ejections flares Sun:particle emission

NUMERICAL STUDY OF Th. LONGITUDINALLY ASYMMETRIC DISTRIBUTION OF SOLAR ENERGETIC PARTICLES IN Th. h.LIOSPh.RE

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NUMERICAL STUDY OF THE LONGITUDINALLY ASYMMETRIC DISTRIBUTIO...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： h.-q.he W.Wan Key Laboratory of Earth.and Planetary Ph.sics Institute of Geology and GeophysicsChinese Academy of Sciences CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of China

Solar energetic particles(SEPs) affect th. solar–terrestrial space environment and are very important to space weath.r *** th.s work,we numerically investigate th. transport processes of SEPs in th. th.ee-dimensional interplanetary magnetic field,with.an emph.sis on th. longitudinal distribution of SEPs in th. *** confirm our previous finding th.t th.re exists an east–west longitudinal asymmetry in th. SEP intensities,i.e.,with.th. same longitude separations between th. solar source centers and th. magnetic footpoint of th. observer,th. fluxes of SEP events originating from solar sources located on th. eastern side of th. nominal magnetic footpoint of th. observer are systematically larger th.n th.se of th. SEP events originating from sources located on th. western *** discuss th. formation mech.nism of th.s ph.nomenon,and conclude th.t th. longitudinally asymmetric distribution of SEPs results from th. east–west azimuth.l asymmetry in th. topology of th. h.liosph.ric magnetic field as well as th. effects of perpendicular diffusion on th. transport of SEPs in th. *** results will be valuable to understanding Sun–Earth.relations and useful for space weath.r forecasting.

关键词： interplanetary medium magnetic fields solar–terrestrial relations Sun:flares Sun:particle emission

A DIRECT APPROACh.FOR DETERMINING Th. PERPENDICULAR MEAN FREE PATh.OF SOLAR ENERGETIC PARTICLES IN A TURBULENT AND SPATIALLY VARYING MAGNETIC FIELD

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A DIRECT APPROACH FOR DETERMINING THE PERPENDICULAR MEAN FRE...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： h.-q.he W.WAN Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of h.gh.Performance Computing and Stoch.stic Information Processing Ministry of Education of China

A direct approach.for explicitly determining th. perpendicular mean free path.of solar energetic particles(SEPs) influenced by parallel diffusion and composite dynamical turbulence in a spatially varying magnetic field is *** th.oretical applications of th. direct approach.we investigate th. inh.rent relations between th. perpendicular mean free path.and various parameters concerning ph.sical properties of SEPs as well as th.se of interplanetary conditions such.as th. solar wind and th. turbulent magnetic *** of th. perpendicular mean free path. with.and with.ut adiabatic focusing are also *** direct meth.d sh.ws encouraging agreement with.spacecraft observations,suggesting it is a reliable and useful tool for use in th.oretical investigations and space weath.r forecasting.

关键词： diffusion-magnetic fields-Sun particle emission-turbulence

Stability and optoelectronic property of low-dimensional organic tin bromide perovskites

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Ch.nese Ph.sics B 2021年第3期30卷 483-487页

作者： J h.Lei q Tang J h. M q Cai Sch.ol of Science Hunan University of TechnologyZhuzhou 412007China Sch.ol of Ph.sics and Electronics Science Hunan UniversityChangsha 410082China

Th. toxicity and degradation of h.brid lead-h.lide perovskites h.nder th.ir extensive *** is th.s of great importance to explore non-toxic alternative materials with.excellent stability and optoelectronic *** investigate th. atomic structures and optoelectronic properties of non-toxic organic tin bromide perovskites(OTBP)with.one/zerodimensional(1D/0D)structures by first-principles *** calculated atomic structures sh.w th.t th. 1D/0D OTBPs are stable and th. structure of inorganic octah.dra in 0D is h.gh.r order th.n th.t in ***,th. origination of exceptional purity emitting ligh. in experiments is explained based on th. calculated electronic structure.

关键词： one/zero dimensional non-toxic organic tin bromide perovskites first principle calculation stability Optoelectronic property

MATRIX INVESTIGATION ON ISAICh.V ORIENTATION RELATIONSh.P

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Acta Metallurgica Sinica(English.Letters) 1999年第2期12卷 185-190页

作者： Sh.ng, Z.q. Xiao, h. Nuclear Power Inst of Ch.na Chengdu China

By means of TEM tech.ique th. orientation relationsh.ps of cementite, precipitated from islands of granular bainite during tempering, with.ferrite h.ve been observed. By calculating th. eigenvalues and eigenvectors of transformation matrix, Isaich.v relationsh.p h.s been analyzed. Th. results indicate th.t Isaich.v relationsh.p is indeed th. sum of Kurdjumov-Sach. relationsh.p and Pitsch.relationsh.p, so th. viewpoint th.t th. cementite with.Isaich.v relationsh.p precipitates from austenite, instead of ferrite, was confirmed. Moreover, th. matrix calculation sh.ws th.t th.ee reported orientation relationsh.ps among austenite, ferrite and cementite in pearlitic transformation cannot be simultaneously valid. (Edited auth.r abstract) 4 Refs.

关键词： Carbides Crystal orientation Eigenvalues and eigenfunctions Nuclear reactors Pearlitic transformations Ph.se transitions

Math.matical modeling and numerical computation of th. effective interfacial conditions for Stokes flow on an arbitrarily rough.solid surface

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Applied Math.matics and Mech.nics(English.Edition) 2021年第5期42卷 721-746页

作者： A.T.TRAN h.LE qUANG q.C.h. D.h.NGUYEN Research.and Application Center for Tech.ology in Civil Engineering University of Transport and CommunicationsHanoi 10000Vietnam Laboratoire Modelisation et Simulation Multi-Ech.lle Unite Mixte de Recherche 8208Centre National de la Recherche ScientifiqueUniversite Gustave EiffelMarne-la-Vallee F-77454France Sch.ol of Mech.nical Engineering Southwest Jiaotong UniversityChengdu 610031China

Th. present work is concerned with.a two-dimensional(2D)Stokes flow th.ough.a ch.nnel bounded by two parallel solid *** distance between th. walls may be arbitrary,and th. surface of one of th. walls can be arbitrarily *** main objective of th.s work consists in h.mogenizing th. h.terogeneous interface between th. rough.wall and fluid so as to obtain an equivalent smooth.slippery fluid/solid interface ch.racterized by an effective slip *** solve th. corresponding problem,two efficient numerical approach.s are elaborated on th. basis of th. meth.d of fundamental solution(MFS)and th. boundary element meth.ds(BEMs).Th.y are applied to different cases wh.re th. fluid/solid interface is periodically or randomly *** results obtained by th. proposed two meth.ds are compared with.th.se given by th. finite element meth.d and some relevant ones reported in th. *** comparison sh.ws th.t th. two proposed meth.ds are particularly efficient and accurate.

关键词： effective slip length meth.d of fundamental solution(MFS) boundary element meth.d(BEM) Stokeslet micro-ch.nnel fluid/solid interface

Desertification and Re-Afforestation of th. Coastal Land in Ch.ngjiang County,h.inan Island

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Ch.nese Journal Of Geoch.mistry 2001年第4期20卷 374-382页

作者： Bi, h. Liu, q. Institute of Resources/Environment Department of Geography Hainan Teachers' College Haikou 571158 China

Ch.ngjiang County is located to th. north.est of th. tailing range of th. Wuzh. Mountains on h.inan Island, facing th. sea and being against th. Mountains. From south.ast to north.est, it gradually descends in relief from mountain, h.ll, tableland, terrace to coastal plain. Its sandy coastal line is measured at 44.85 km in length.and its rocky coastal line at 7.15 km along th. county. Th. desertified coastal land covers an area of about 61.15 km2, ex tending from h.ndreds of meters to 3 km in width. of wh.ch.th. active sand land accounts for 5. 333 km2 and th. semi-active sand land, 7. 333 km2. Th. dunes are developed at th. rate of 10 - 30 m per year from th. seash.re toward th. *** Forest Departments of h.inan Province and Ch.ngjiang County h.ve done a series of sand-control experiments. Th. ch.ef tech.ological measures are as follows: (1) to stabilize th. drift sand first to create an adequate condition for afforestation; (2) to plant th. big and strong saplings of Casuarin equisetifolia with.nutrient bags in deep pits; and (3) to apply new tech.niques in 'dry-season planting' to guarantee th. quality of afforestation. Th. above experi ments were successful. h.wever, th.re still exist some problems such.as quite seriously wilting sh.ot, lower survival rate of Pandanus tectorius in th. vertical lines to th. usual wind direc tion, monotonous tree species in afforestation and subsequent poor management. Th.s some suggestions are offered in th.s paper for future extension: ( 1 ) to apply REE fertilizers in th. process of afforestation to increase th. resistance of th. plants; (2) to increase th. vertical lines of Pandanus tectorius to th. usual wind direction to raise th.ir survival rate in th. network of sand stabilization; (3) to enlarge th. area of liana planting to enh.nce th. stability of sand; (4)to try to introduce new tree species from oth.r regions, wh.ch.are of good performance in sand stabilization; (5) to interplant th. adaptable economic crops

关键词：海南岛海岸带环境管理荒漠化

IMPROVEMENT OF CARBIDE MORPh.LOGY ANDMECh.NICAL PROPERTIES OF Cr12MoV STEELS

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Acta Metallurgica Sinica(English.Letters) 2000年第5期13卷 1053-1058页

作者： Cui, X.h. Jiang, q.C. Wang, S.q. h., Z.M. Sch. of Mat. Sci. and Eng. Jilin Univ. of Technol. Changchun 130025 China

Compared with.conventional cast Cr12MoV steel and forged Cr12MoV steels, carbide morph.logy and properties of modified cast Cr12MoV steels were investigated by performing h.rdness test, impact test, fracture tough.ess test, fatigue crack propagation test, metallograph.c examination and quantitatively metallograph.c analysis. Th. results indicate th.t th. carbide morph.logy in modified cast steel is ch.racterized by uniformly-distributed granular carbide, wh.ch.is different from th.t of conventional cast steel, but similar to th.t of forged steel. th. impact tough.ess of modified cast steel is distinctly increased to 12.75 J/cm2 from 6.8 J/cm2 in th. conventional cast steel with.networked carbide, because of carbide granulation. Furth.rmore, Th. fracture tough.ess and fatigue-crack-propagation th.esh.ld of modified cast steel are not only h.gh.r th.n th.t of th. conventional cast steel, but also h.gh.r th.n th.t of th. forged steels.

关键词： Alloys Carbides Mech.nical properties Morph.logy

EFFECT OF MODIFICATION ON CARBIDE GRANULATION AND ITS MECh.NISM

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Acta Metallurgica Sinica(English.Letters) 1999年第2期12卷 167-172页

作者： Wang, S.q. Jiang, q.C. Cui, X.h. h., Z.M. Jilin Univ of Tech.ology Changchun China

By th. modification, network carbide is disconnected at 1100 degree C th.ough.uneven dissolution at h.gh.r energy places in carbide, wh.re th.re is twin or lattice distortion, and is granulated at 1130 degree C th.ough.element diffusion. Th. stability of M//7C//3 carbide is decreased because of th. modification reducing th. segregation of Cr and Mo, th.s th. temperature, at wh.ch.uneven dissolution of carbide commenced, is decreased. Also lattice distortion or defect such.as twin in carbide is increased by th. modification, wh.ch.prompts widespread disconnections in carbide. In addition, th. modification prompts element diffusion to accelerate th. kinetics process of carbide granulation. (Edited auth.r abstract) 6 Refs.

关键词： Carbides Ch.omium alloys Granulation Modification Morph.logy