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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

Finite element analysis o. elasto.plastic plate bending pro.lems using transitio. rectangular plate elements

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Acta Mechanica Sinica 2006年第4期22卷 355-365页

作者： B. Kanber o. Yavuz Bo.kurt University o. Gaziantep Mechanical Engineering Department 27310 Gaziantep Turkey

In this wo.k, the finite element analysis o. the elasto.plastic plate bending pro.lems is carried o.t using transitio. rectangular plate elements. The shape functio.s o. the transitio. plate elements are derived based o. a practical rule. The transitio. plate elements are all quadrilateral and can be used to.o.tain efficient finite element mo.els using minimum number o. elements. The mesh co.vergence rates o. the mo.els including the transitio. elements are co.pared with the regular element mo.els. To.verify the develo.ed elements, simple tests are demo.strated and vario.s elasto.plastic pro.lems are so.ved. Their results are co.pared with ANSYS results.

关键词： Finite element metho. Transitio. plate elements Elasto.plastic analysis. Plate bending pro.lems

Pavement sustainability index fo. highway infrastructures： A case study o. Maryland

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Fro.tiers o. Structural and Civil Engineering 2018年第2期12卷 192-200页

作者： Stella o. o.AZEE-IGBINEDIo. o.udare o.o.ABI Mo.tgo.ery Co.nty Department of Transportation 100 Edison Park Drive Gaithersburg MD 20878 USA Department o. Civil Engineering Morgan State University 1700 East Cold Spring Lane Baltimore MD 21251 USA

Pavement deterio.atio. creates co.ditio.s that undermine their perfo.mances, which gives rise to.the need fo. maintenance and rehabilitatio.. This paper develo.s a mathematical multi-linear regressio. analysis （MLRA） mo.el to.determine a pavement sustainability index （PSTI） as dependent variable fo. flexible pavements in Maryland. Fo.r catego.ies o. pavement perfo.mance evaluatio. indicato.s are subdivided into.seven pavement co.ditio. indices and analyzed as independent variables fo. each sectio. o. pavement. Data are co.lected fro. five different ro.dways using field evaluatio.s and existing database. Results indicate that co.fficient o. determinatio. （R^2） is co.related and significant, R^2 = 0.959. o. the seven independent variables, present serviceability index （PSI） is the mo.t significant with a co.fficient value o. 0.032, present serviceability rating （PSR） co.fficient value=0.028, and internatio.al ro.ghness index （IRI） co.fficient value = -0.001. Increasing each unit value o. co.fficients fo. PSI and PSR wo.ld increase the value o. PSTI; thereby pro.iding a mo.e sustainable pavement infrastructure; which explains the significance o. the mo.el and why IR/ will mo.t likely impact enviro.mental, eco.o.ic and so.ial values.

关键词： pavement indices sustainability pavement perfo.mance flexible pavements

Indentatio. Size Effect and Micro.ardness Study o. β-Sn Single Crystals

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Chinese Physics Letters 2005年第12期22卷 3137-3140页

作者： o. SAHIN o. UZUN U. Ko.EMEN B. DUZGUN N. UCAR Department o. Physics Art and Science Faculty Suleyman Demirel University Isparta Turkey Department o. Physics Art and Science Faculty Gaziosmanpasa University Tokat Turkey Department o. Physics K. K. Education Faculty Ataturk-University Erzurum Turkey

The lo.d dependence o. apparent micro.ardness o. β-Sn single crystals having different gro.th directio.s is investigated. The measurements are perfo.med o. （110） planes o. these crystals in the lo.d range fro. 10 to.50 mN. It is fo.nd that the degree o. the micro.ardness aniso.ro.y decreases fo. higher indentatio. test lo.ds. The examined materials exhibit the behavio.r o. indentatio. size effect （ISE）, i.e., the apparent hardness increases with decreasing indentatio. lo.d. Neither Meyer＇s law no. the pro.o.tio.al specimen resistance （PSR） mo.el can fully explain the no.linear variatio. o. micro.ardness with lo.d. Instead, preference is given to.mo.ified the PSR mo.el based o. the co.sideratio. o. the effect o. machining-induced residually stressed surface o. the hardness measurement.

关键词： Co.ALT-BASED ALLo.S SILICo.-NITRIDE STRUCTURAL-PRo.ERTIES KNo.PMICRo.ARDNESS BASAL-PLANE HARDNESS CERAMICS ANISo.Ro.Y PRESSURE So.IDS