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Space-time descriptio. o. transverse pho.o.s: near-field aspects

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Science China(Physics,Mechanics & Astro.o.y) 2012年第8期55卷 1389-1393页

作者： KELLER o. Institute o. Physics and Nano.echno.o.y Aalborg University

A mean po.itio. state based o. the gauge invariant transverse vecto. po.ential is used to.co.vert single-pho.o. states in Hilbert space to.pho.o. wave packets in direct space. The resulting pho.o. wave-mechanical descriptio. leads to.scalar pro.ucts which relate to.co.ariant integratio. o. the light co.e. A new co.relatio. matrix displays the spatial lo.alizatio. pro.lem fo. single pho.o.s in an explicit manner in space-time. The co.relatio. matrix essentially is the pro.ectio. o. the time-o.dered Feynman pho.o. pro.agato. o.to.the transverse pho.o. subspace. The present pho.o. wave-mechanical fo.malism is generalized to.two.pho.o. dynamics. In the diamagnetic limit the transverse pho.o. beco.es massive in its interactio. with matter, and the co.relatio. matrix fo. massivepho.o. interactio., which can be used in studies o. evanescent-pho.o. mediated co.plings, is analyzed. o. the basis o. the present fo.malism the existence o. a dynamical near-field Aharo.o.-Bo.m effect is predicted.

关键词： o.e-pho.o. wave mechanics near-field o.tics co.relatio. matrix transverse pho.o. mass

Magnetic cycles o. Sun-like stars with different levels o. co.o.al and chro.o.pheric activity——co.pariso. with the Sun

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Research in Astro.o.y and Astro.hysics 2016年第9期16卷 123-136页

作者： Elena Shimano.skaya vasiliy Bruevich Elena Bruevich Sternberg Astro.o.ical Institute Moscow State University

The atmo.pheric activity o. the Sun and Sun-like stars is analyzed invo.ving o.servatio.s fro. the HK-pro.ect at the Mo.nt Wilso. o.servato.y, the Califo.nia and Carnegie Planet Search Pro.ram at the Keck and Lick o.servato.ies and the Magellan Planet Search Pro.ram at the Las Campanas o.servato.y. We sho. that fo. stars o. E G and K spectral classes, the cyclic activity, similar to.the 11-yr so.ar cycle, is different： it beco.es mo.e pro.inent in K-stars. Co.parative study o. Sun-like stars with different levels o. chro.o.pheric and co.o.al activity co.firms that the Sun belo.gs to.stars with a lo. level o. chro.o.pheric activity and stands apart amo.g these stars by its minimum level o. co.o.al radiatio. and minimum level o. variatio.s in pho.o.pheric flux.

关键词： Sun activity -- Sun-like stars activity

Derivatio. o. a segregatio.-mixing equatio. fo. particles in a fluid medium

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Applied Mathematics and Mechanics(English Editio.) 2009年第6期30卷 765-770页

作者： Do.ald o. Beso.g Department o. Numerical Analysis and Co.puter Science (NADA) Royal Institute of TechnologyS-10044 StockholmSweden

The main purpo.e o. this wo.k is to.sho. that the gravity term o. the segregatio.-mixing equatio. o. fine mo.o.disperse particles in a fluid can be derived fro. first-principles （i.e., elementary physics）. o.r derivatio. o. the gravity-driven flux o. particles leads to.the simplest case o. the Richardso. and Zaki co.relatio.. Sto.es velo.ity also.naturally appears fro. the physical parameters o. the particles and fluid by means o. derivatio. o.ly. This derivatio. fro. first-principle physics has never been presented befo.e. It is applicable in small co.centratio.s o. fine particles.

关键词： gravity segregatio. Kynch batch flux first-principles derivatio. Burger-type equatio.

Do.ains o. ho.o.o.phy fo. Fo.rier transfo.ms o. so.utio.s to.discrete co.vo.utio. equatio.s

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Science China Mathematics 2017年第6期60卷 1005-1018页

作者： KISELMAN Christer o. Department o. Info.matio. Techno.o.y Uppsala University Uppsala SE-751 05 Sweden

We study so.utio.s to.co.vo.utio. equatio.s fo. functio.s with discrete suppo.t in R^n, a special case being functio.s with suppo.t in the integer po.nts. The Fo.rier transfo.m o. a so.utio. can be extended to.a ho.o.o.phic functio. in so.e do.ains in C^n, and we determine po.sible do.ains in terms o. the pro.erties o. the co.vo.utio. o.erato..

关键词： discrete co.vo.utio. do.ain o. ho.o.o.phy Fo.rier transfo.matio.

Identificatio., iso.atio. and characterizatio. o. the antifeedant co.stituent o. Clausena anisata against Helico.erpa armigera （Lepido.tera： No.tuidae）

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Insect Science 2009年第3期16卷 247-253页

作者： o.ufemi o. R. Pitan o. o. Ayelaagbe Ho.g-Lei Wang Chen-Zhu Wang State Key Labo.ato.y o. Integrated Management o. Pest insects and Ro.ents Institute of Zoology Chinese Academy of Sciences BeijingChina Department o. Cro. Pro.ectio. University of Agriculture Abeokuta Department o. Chemistry University of Ibadan IbadanNigeria

Hexane, petro.eum ether, chlo.o.o.m, ethyl acetate, methano. and water extracts o. Clausena anisata [（Willd.） Ho.k E Ex Benth] leaves and ro.ts were evaluated against Helico.erpa armigera （Hubner） fo. antifeedant activities. Antifeedant activity was co.firmed, and was fo.nd to.be higher in ro.t extracts than tho.e o. the leaf. Chlo.o.o.m and petro.eum ether extracts o. the ro.t sho.ed stro.gest antifeedant activities （DC50s [co.centratio. （C） causing 50% deterrence co.pared with the co.tro.] 0.014% and 0.016% respectively）, and ro.t extracts were fractio.ated using silica gel co.umn chro.ato.raphy. o.e fractio. o. the chlo.o.o.m and o.e o. the petro.eum ether ro.t extracts was active; and o. the basis o. mass spectro.co.y and ^1H and ^13C nuclear magnetic reso.ance spectral data, the active co.po.nds in the two.fractio.s were co.firmed to.be identical, and identified as o.tho. [2H-1-Benzo.yran-2-o.e, 7-metho.y-8-（3-methyl-2-butenyl）]. The highest co.centratio. o. o.tho. was fo.nd in the chlo.o.o.m ro.t extract. Antifeedant activities o. the ro.t extracts, as measured by DC50 values, were highly co.related with their o.tho. co.tents. Appro.imately 99% o. the variatio. in bio.ctivity o. the ro.t extracts co.ld be acco.nted fo. by variatio. in o.tho. co.tent; o.tho. therefo.e, appeared to.be an antifeedant co.po.ent o. C. anisata to.H. armigera. This may pro.ide a new appro.ch to.managing this pest.

关键词： active ingredient antifeedant Clausena anisata Helico.erpa armigera,o.tho. ro.t

TIME AND No.M o.TIMAL Co.TRo.S:A SURVEY o. RECENT RESULTS AND o.EN PRo.LEMS

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Acta Mathematica Scientia 2011年第6期31卷 2203-2218页

作者： H. o. Fatto.ini Department o. Mathematics University of California Los Angeles

We present in this paper a survey o. recent results o. the relatio. between time and no.m o.timality fo. linear systems and the infinite dimensio.al versio. o. Po.tryagin＇s maximum principle. In particular, we discuss o.timality （o. no.o.timality） o. singular co.tro.s satisfying the maximum principle and smo.thness o. the co.tate in functio. o. smo.thness o. the target.

关键词： linear co.tro. systems in Banach spaces time o.timal pro.lem no.m o.timal pro.lem

Extractio. o. nio.ium fro. sulfate leach liquo. o. Egyptian o.e sample by triazo.o.uinazo.ino.e

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中国有色金属学会会刊：英文版 2009年第2期19卷 474-478页

作者： o. M. EL HUSSAINI Nuclear Materials Autho.ity P.O. Box 530 El MaadiCairoEgypt

The refracto.y nio.ium bearing minerals,Samarskite,Ferguso.ite,Betafite and Pyro.hlo.e o. the o.e sample o.tained fro. Kadabo.a,Egypt,was subjected to.sulfuric acid leaching using acid co.centratio.s varied fro. 17.6 to.4.5 mo./ L. The extractio. o. nio.ium fro. the sulfate leach liquo.s was do.e using the synthesized 8,9-dihydro.1,2,4]triazo.o.1,5-a]quinazo.in6(7H)-o.e disso.ved in methylene chlo.ide. It has been fo.nd that extractio. efficiency o. 84% was achieved by co.tacting equal vo.umes o. 0.32% extractant with 4.5 mo./L sulfate so.utio. fo. 15 min. The stripping was perfo.med by 0.5 mo./L HF with efficiency o. 86.7%.

关键词：硫酸浸出液矿石样品提取效率铌矿物埃及使用浓度二氯甲烷硫酸溶液

Structural and superco.ducting pro.erties in Y_(0.6)Gd_(0.4)Ba_2(Nb)Cu_3o.(7-y) cuprates do.ed with nio.ium

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Jo.rnal o. Rare Earths 2012年第3期30卷 241-244页

作者： M. Yilmaz o. Do.an A. K. Educatio. Faculty Department of Physics Konya University

Po.ycrystalline YBa2Cu3o.-y （YBCo. and Y0.6Gd0.4Ba2-xNbxCu3o.-y （YGBNCo. co.po.nds with 0≤x≤0.225 were synthesized using standard so.id state reactio. technique. The structure fo. all samples was characterized by X-ray difference （XRD） and scanning electro. micro.co.y （SEM）. The transpo.t pro.erties were measured by the （FPP） metho. in the temperature range fro. 70 to.130 K. As the Nb co.tent in the samples increased, a diffused phase indicating a nio.ium pero.skite phase and a small amo.nt o. unidentified phase appeared. With the increase o. Nb co.tent, the superco.ducting transitio. temperature Tco.set increased slo.ly with x≤0.125, and then it remained unchanged o. slo.ly decreased with 0.125≤x≤0.225. It co.ld be fo.nd that there was a slo. decrease o. zero.resistance temperature, Tco.fset, with the increase o. Nb co.tent. The larger transitio. width might result fro. the YBa2Nbo. phase, impurity and unidentified phases o. the sample due to.the Nb do.ing.

关键词： Y0.6Gd0.4Ba2Cu3o.-y cuprates Gd and Nb co.do.ing structural and superco.ducting pro.erties rare earths

Creep Behavio.r o. Fe-Mn Binary Allo.s

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Chinese Physics Letters 2006年第11期23卷 3037-3040页

作者： o. Sahin, N. Ucar Department o. Physics Art and Science Faculty Suleyman Demirel University Isparta Turkey

Tensile creep behavio.r o. fine-grained Fe-Mn binary allo.s co.taining 0.42-1.21 wt. % Mn has been investigated in the temperature range fro. ro.m temperature to.475K under 10-50 MPa. Tensile tests are carried o.t with a co.stant cro.s-head speed under uniaxial lo.d at a strain rate 10^-4s^-1. Stress expo.ent and activatio. energy are determined to.clarify defo.matio. mechanism. The o.tained variatio. o. steady state creep rate with respect to.the applied stress fo. Fe-Mn binary allo.s exhibits two.distinct regimes at abo.t 20 MPa, indicating a po.sible change in creep mechanism. The average stress expo.ent is appro.imately 2.2, which is a characteristic o. grain bo.ndary sliding in the allo.s. The activatio. energy fo. plastic flo. varies fro. 135 to.92k J/mo., depending o. the Mn co.tent.

关键词： HIGH-TEMPERATURE CREEP STEADY-STATE CREEP PB-SB ALLo.S TRANSFo.MATIo. STRESS