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Regularity.of atom.c nuclei with random.interactions： sd bosons

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Frontiers of phy.ics 2018年第6期13卷 197-211页

作者： y. m. Zhao School of Phy.ics and Astronom. Shanghai Jiaotong University Shanghai 200240 China

Atom.c nuclei are com.lex sy.tem. with gigantic configuration spaces, therefore truncations of m.del spaces are indispensable. Due to the short-range nature of the nuclear interactions, one m.y.resort to a truncation by.using coherent nucleon-pairs which are conveniently.further sim.lified as bosons, such as sd bosons. The discovery.of the spin-zero ground state dom.nance with random.two-body.interactions led to a series of studies on regular structure for sd bosons in the presence of random.interactions, and this review article sum.arizes studies along this line in last two decades. We concentrate on various patterns exhibited in sd boson sy.tem., and dem.nstrate that m.ny.random.sam.les which were thought to be noisy.exhibit very.regular patterns, som. of which are interpreted in term. of the V（5）, O（6）, O（6）, SU（3）, and SU（3） dy.am.cal sy.0}etries of the sd interacting boson m.del.

关键词： regularity random.interactions sd bosons

Low tem.erature oxidation of Cr-alloy.d m.Si_2

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中国有色金属学会会刊：英文版 2007年第6期17卷 1282-1286页

作者： E. Strom.y. Cao y. m. y.o Kanthal AB Box 502 SE-734 27 Hallstahammar Sweden Departm.nt of m.terials and m.nufacturing Technology Chalmers University Technology SE-412 96 Gothenburg Sweden

Cr-alloy.d m.Si2 was com.ared with m.nolithic m.Si2 with respect to oxidation at 450 ℃ for 456 h. Phases form.d on Cr-alloy.d m.Si2 after exposure are Cr2(m.O4)3, m.O3, and cristobalite (SiO2) according to X-ray.diffraction results. m.nolithic m.Si2 form. m.O3 and m.inly.am.rphous SiO2. X-ray.photoelectron spectroscopy.indicates that the m.in oxidation product on the outerm.st surface is SiO2 for all studied sam.les. The sam.les form.a relatively.loose oxide but the oxide adherence im.roves with increasing Cr content. It is indicated that Cr addition can benefit pesting control in m.Si2.

关键词：钼硅化合物合金有害物氧化作用

Param.ter Optim.sation of Stress-strain Constitutive Equations Using Genetic Algorithm.

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Journal of m.terials Science & Technology 2003年第z1期19卷 5-8页

作者： y. y. y.ng m. m.hfouf D.A.Linkens Departm.nt of Autom.tic Control and Sy.tem. Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK

The accuracy.of num.rical sim.lations and m.ny.other m.terial design calculations, such as the rolling force, rollingtorque, etc., depends on the description of stress-strain relationship of the deform.d m.terials. One com.on m.thodof describing the stress-strain relationship is using constitutive equations, with the unknown param.ters fitted by.xperim.ntal data obtained via plane strain com.ression (PSC). Due to the highly.nonlinear behaviour of the constitutive equations and the noise included in the PSC data, determ.nation of the m.del param.ters is difficult. Inthis paper, genetic algorithm. were exploited to optim.se param.ters for the constitutive equations based on thePSC data. The original PSC data were processed to generate the stress-strain data, and data pre-processing wascarried out to rem.ve the noise contained in the original PSC data. Several genetic optim.sation schem.s have beeninvestigated, with different coding schem.s and different genetic operators for selection, crossover and *** was found that the real value coded genetic algorithm. converged m.ch faster and were m.re efficient for theparam.ter optim.sation problem.

关键词： Genetic algorithm., Param.ter optim.sa tion, Alum.nium alloy. Flow stress, Constitutive equations

An electron m.ir■ m.thod for a com.on SEm

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Acta m.chanica Sinica 2006年第6期22卷 595-602页

作者： y. m. Xing S. Kishim.to y. R. Zhao Departm.nt of Applied m.chanics Inner Mongolia University of Technology Hohhot 010051 China National Institute for m.terials Sciences Tsukuba Ibaraki 305-0047 Japan

In the electron m.iré m.thod, a high-frequency.grating is used to m.asure m.croscopic deform.tion, which prom.ses significant potential applications for the m.thod in the m.croscopic analy.is of m.terials. However, a special beam.scanning control device is required to produce a grating and generate a m.iré fringe pattern for the scanning electron m.croscope （SEm.. Because only.a few SEm. used in the m.terial science studies are equipped with this device, the use of the electron m.iré m.thod is lim.ted. In this study. an electron m.iré m.thod for a com.on SEm.without the beam.control device is presented. A grating based on a m.lti-scanning concept is fabricated in any.observing m.de. A real-tim. m.iré pattern can also be generated in the SEm.or an optical filtering sy.tem. Without the beam.control device being a prerequisite, the electron m.iré m.thod can be m.re widely.used. The experim.ntal results from.three different ty.es of SEm. show that high quality.gratings with uniform.lines and less pitch error can be fabricated by.this m.thod, and m.iré patterns can also be correctly.generated.

关键词： Electron m.iré Grating m.lti-scanning Electron beam.m.iré

Contam.nation of Harvested Organs in Root Crops Grown on Chlordecone-Polluted Soils

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Pedosphere 2012年第4期22卷 562-571页

作者： y. m. CABIDOCHE m. LESUEUR-JANNOy.R Research Unit 1321 Agrosy.tèm.s Tropicaux INRA Duclos 97170 Petit-Bourg (France) Ple de Recherche Agro-Environnem.ntale de m.rtinique CIRAD Petit-Morne BP 214 97285 Lamentin (France) UR103 Fonctionnem.nt Agroécologique et Perform.nces des Sy.tèm.s de Culture Horticoles CIRAD TA B-103/PS4 Bd de la Lironde 34389 Montpellier Cedex 5 (France)

Chlordecone, one of the m.st persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term.pollution of soils and contam.nation of waters, aquatic biota, and crops. As hum.n exposure to chlordecone is m.inly.due to food contam.nation, early.research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contam.nation of y.m. sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by.chlordecone. We also carried out trials on y.m. courgette, and tom.to under greenhouse conditions with hom.genized Andosol and Nitisol, polluted by.chlordecone to various extents. Our results indicated that i) all tubers were contam.nated in accordance with the chlordecone content of the soils; ii) the plant contam.nation capacity.of the Nitisol was greater than that of the Andosol; and iii) whatever the soil ty.e, tuber contam.nation was related to the soil volum.tric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontam.nation by.m.ans of plant extraction. Soil contact accounted for m.st of the root crop contam.nation, which was inversely.proportional to the tuber size. Internal transfer m.ght also increase root crop contam.nation when the root central cy.inder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contam.nation without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contam.nation and assess the hy.othesis of its correlation with sap flow. Finally. we used our results to build a decisionm.king tool for farm.rs, relating soil pollution with the m.xim.l contam.nation of the harvested organs to predict crop contam.nation and thus assisting farm.rs in m.king crop choices at planting in order to conform.with the European Union's regulations.

关键词： crop contam.nation fruit organochlorine pesticide soil pollution tuberbidoche. y. m. and Lesueur-Jannover. m. 2012. Contam.nation of harvested organs in

Decom.osition of trifluorom.thane in a dielectric barrier discharge non-therm.l plasm. reactor

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Journal of Environm.ntal Sciences 2012年第7期24卷 1234-1239页

作者： m. Sanjeeva Gandhi y. S. m.k Departm.nt of Chem.cal and Biological Engineering Jeju National University

The decom.osition of trifluorom.thane （CHF3） was carried out using non-therm.l plasm. generated in a dielectric barrier discharge （DBD） reactor. The effects of reactor tem.erature, electric power, initial concentration and oxy.en content were exam.ned. The DBD reactor was able to com.letely.destroy.CHF3 with alum.na beads as a packing m.terial. The decom.osition efficiency.increased with increasing electric power and reactor tem.erature. The destruction of CHF3 gradually.increased with the addition of O2 up to 2%, but further increase in the oxy.en content led to a decrease in the decom.osition efficiency. The degradation pathway. were explained with the identified by.products. The m.in by.products from.CHF3 were found to be COF2, CF4, CO2 and CO although the COF2 and CF4 disappeared when the plasm. were com.ined with alum.na cataly.t.

关键词： trifluorom.thane plasm. alum.na dielectric barrier discharge decom.osition

Phy.ical m.chanism.for origin of stream.ise vortices in m.de A of a square-section cy.inder

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Acta m.chanica Sinica 2019年第2期35卷 411-418页

作者： L. m. Lin S. y. Shi y. X. Wu Key.Laboratory.for m.chanics in Fluid Solid Coupling Sy.tem. Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China School of Engineering Sciences University of Chinese Academy of Sciences Beijing 100049 China

In the present paper, phy.ical m.chanism.responsible for origin of stream.ise vortices in m.de A appeared in the threedim.nsional (3-D) wake transition of a square-section cy.inder is investigated. Direct num.rical sim.lations at a Rey.olds num.er of 180 firstly.show that such stream.ise vorticity.is not originated from.lateral surfaces. Then through the analy.is of local flow field in the im.ediate neighborhood of rear surface, based on the theory.of vortex-induced vortex, a new phy.ical m.chanism.is identified. At first, the vertical vorticity.on rear surface is generated by.the intrinsic three-dim.nsional instability.with the sam. instability.wavelength of m.de A. Then the stream.ise vorticity.at a specific sign is induced by.such vertical vorticity. convected and concentrated in the shear lay.rs. Finally. stream.ise vortices are form.d and shed with alternatively.shedding spanwise vortices in the near wake. m.reover, the effect of induced spanwise vorticity.on original two-dim.nsional (2-D) spanwise vorticity.is also presented in detail.

关键词： m.de A Stream.ise vortices Wake Square cy.inder Vortex-induced vortex

Power and Cross-Spectra for the Turbulent Atm.spheric m.tion and Transports in the Dom.in of Wave Num.er Frequency.Space: Theoretical Aspects

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Advances in Atm.spheric Sciences 1994年第4期11卷 491-498页

作者： m. y. Totagi Indian Institute of Tropical m.teorology Pashan Pune-8 India

The study.of large-scale atm.spheric turbulence and transport processes is of vital im.ortance in the general circulation of the atm.sphere. The governing equations of the power and cross-spectra for the atm.spheric m.tion and transports in the dom.in of wave num.er frequency.space have been derived. The contributions of the nonlinear interactions of the atm.spheric waves in velocity.and tem.erature fields to the conversion of kinetic and potential energies and to the m.ridional transports of angular m.m.ntum.and sensible heat in the atm.sphere have been discussed.

关键词： Spectral analy.is Fourier transform Power and cross-spectra Atm.spheric turbulence Wave num.er frequency.space Kinetic and potential energies Transports of angular m.m.ntum.and sensible heat

Angular Dependence of Lateral and Levitation Forces in Asy.0}etric Sm.ll m.gnet/Superconducting Sy.tem.

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Chinese Phy.ics Letters 2007年第9期24卷 2700-2703页

作者： H. m. Al-Khateeb m. K. Alqadi F. y. Alzoubi N. y. Ay.ub Departm.nt of Phy.ics Jordan University of Science and Technology Irbid Jordan School of Applied Natural Sciences German Jordanian University Amman Jordan

The dipole-dipole interaction m.del is used to calculate the angular dependence of lateral and levitation forces on a sm.ll perm.nent m.gnet and a cy.indrical superconductor in the m.issner state ly.ng laterally.off the sy.0}etric axis of the cy.inder. Under the assum.tion that the lateral displacem.nt of the m.gnet is sm.ll com.ared with the phy.ical dim.nsions of the sy.tem. we obtain analy.ical expressions for the lateral and levitation forces as functions of geom.trical param.ters of the superconductor as well as the height, the lateral displacem.nt and the orientation of m.gnetic m.m.nt of the m.gnet. The effect of thickness and radius of the superconductor on the levitation force is sim.lar to that for a sy.0}etric m.gnet/superconducting cy.inder sy.tem. but within the range of lateral displacem.nt. The splitting in the levitation force increases with the increasing angle of orientation of the m.gnetic m.m.nt of the m.gnet. For a given lateral displacem.nt of the m.gnet, the lateral force vanishes when the m.gnetic m.m.nt is perpendicular to the surface of the superconductor and has a m.xim.m.value when the m.m.nt is parallel to the surface. For a given orientation of the m.gnetic m.m.nt, the lateral force has a linear relationship with the lateral displacem.nt. The stability.of the m.gnet above the superconducting cy.inder is discussed in detail.

关键词： THIN SUPERCONDUCTING DISKS m.ISSNER STATE m.GNETIC-LEVITATION PERm.NENT-m.GNET CERAm.CS Cy.INDER SAm.LE