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Uniquenes. theorems.for an impuls.ve s.urm-Liouville b.undary value prob.em

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Applied Mathematics.A Journal of Chines. Univers.ties. 2012年第4期27卷 428-434页

作者： A. s. Ozkan b. Kes.in Department of Mathematics Cumhuriyet UniversitySivas 58140 Turkey

In this.s.udy, an impuls.ve b.undary value prob.em, generated b. s.urm-Liouville differential equation with the eigenvalue parameter contained in one b.undary condition is.cons.dered. It is.s.own that the coefficients...

关键词： invers. Prob.em Weyl Function s.ectrum s.urm-Liouville prob.em.

s.nthes.s. Characterization, Thermal s.ab.lity and Antib.cterial Activity of Coumarin b.s.d Methacrylate Copolymers

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Chines. Journal of Polymer s.ience 2014年第10期32卷 1373-1380页

作者： s. Venkates.n b. Ranjithkumar s. Rajes.kumar K. Anver b.s.a P.G. & Res.arch Department of Chemis.ry C. Abdul Hakeem College Hakeem Nagar Melvisharam-632509Tamil Nadu India Department of b.ochemis.ry Adhiparasakthi College of Arts and Science Kalavai-632506 Vellore Dt TamilNadu India

Monomer of 7-methacryloyloxy-4-methylcoumarin （MAOMC） was.s.nthes.zed and characterized b. FTIR, 1H-NMR and 13C-NMR s.ectros.opy. Copolymers.of MAOMC with b.toxyethylmethacrylate （b.EMA） at different feed compos.tions.were prepared b. free radical s.lution polymerization at （70 ± 1） ℃ in ethylmethylketonc （EMK） us.ng b.nzyl peroxide （b.O） as.an initiator. The copolymers.were characterized b. FTIR and IH-NMR s.ectros.opy. Thermogravimetric analys.s.（TGA） and differential s.anning calorimetry （Ds.） of the copolymers.s.owed moderate thermal s.ab.lity and higher Tg values. Gel permeation chromatography （GPC） was.us.d to find out the molecular weights.of the different copolymers. Antib.cterial activities.of the copolymers.were als. inves.igated agains. the s.lected pathogenic b.cteria＇s. The antib.cterial activity of the copolymer increas.s.as.the MAOMC content increas.s.in the copolymer. This.s.ows.that coumarin moiety plays.a very important role in the antib.cterial activity.

关键词： 7-Methacryloyloxy-4-methylcoumarin Copolymerization Thermogravimetric analys.s Antib.cterial activity

Optimization of flotation variab.es.for the recovery of hematite particles.from b.Q ore

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International Journal of Minerals.Metallurgy and Materials 2013年第7期20卷 605-611页

作者： s.agat s. Rath Hrus.ikes. s.hoo b. Das Cs.R-Ins.itute of Minerals.and Materials.Technology Bhubaneswar 751 013 India

The technology for b.neficiation of b.nded iron ores.containing low iron value is.a challenging tas. due to increas.ng demand of quality iron ore in India. A flotation proces. has.b.en developed to treat one s.ch ore, namely b.nded hematite quartzite （b.Q） containing 41.8wt% Fe and 41.5wt% s.O2,b. us.ng oleic acid, methyl is.b.tyl carb.nol （MIb.）, and s.dium s.licate as.the collector, frother, and dis.ers.nt, res.ectively. The relative effects.of thes. variab.es.have b.en evaluated in half-normal plots.and Pareto charts.us.ng central compos.te rotatab.e des.gn. A quadratic res.ons. model has.b.en developed for b.th Fe grade and recovery and optimized within the experimental range. The optimum reagent dos.ges.are found to b. as.follows. collector concentration of 243.58 g/t, dis.ers.nt concentration of 195.67 g/t, pH 8.69, and conditioning time of 4.8 min to achieve the maximum Fe grade of 64.25% with 67.33% recovery. The predictions.of the model with regard to iron grade and recovery are in good agreement with the experimental res.lts.

关键词： hematite iron ore treatment flotation metal recovery des.gn of experiments mathematical models opti-mization

Development of proces.ing maps.for as.cas. ZE41A magnes.um alloy

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中国有色金属学会会刊：英文版 2010年第1期20卷 22-27页

作者： s. ANb. s.LVAN s. RAMANATHAN R . KARTHIKEYAN b. K. RAGHUNATH Department of Manufacturing Engineering Annamalai University Department of Mechanical Engineering Birla Institute of Technology and Sciences

The hot deformation b.havior of as.cas. ZE41A magnes.um alloy was.s.udied b. employing b.th proces.ing maps.and micros.ructural ob.0}rvations. To ob.ain proces.ing map, hot compres.ion tes.s.were performed over a range of s.rain rates.(0.001-1.0 s.1) and temperatures.(250-450 ℃). Power dis.ipation efficiency (η) and ins.ab.lity parameter [ξ (ε)] were evaluated and proces.ing maps.were developed for the s.rain of 0.5. The dynamic recrys.allization (DRX) and ins.ab.e zones.were identified and validated through micrographs. The proces.ing maps.can b. us.d to s.lect optimum s.rain rates.and temperatures.for effective hot working of the material.

关键词：加工图镁合金热加工温度热变形行为热压缩试验动态再结晶应变率微观结构

Zero-Ab.0}rption Is.lines.in a 2-Photon 2-Level Atom Model

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Communications.in Theoretical Phys.cs 2017年第7期67卷 83-90页

作者： s.s.hassan R.A.Alharb.y King Ab.ulaziz Univers.ty Faculty of Science Mathematics Department P.O. Box 42696 Jeddah 21551 Kingdom of Saudi Arabia

The c-numb.r atomic b.och equations.modelling the coupling of a 2-photon 2-1evel s.ngle atom with a non-res.nant （A # O） s.ueezed vacuum （s.） radiation res.rvoir s.ow that：（i） The quantum interference （QI） proces., of parameter f O, b.tween the 2-photon trans.tion channels.caus.s.coupling of the atomic variab.es.（invers.on and polaris.tion）, and, （ii） The s. res.rvoir parameters.（N, M） induce periodic coefficients.and hence inhib.ted os.illatory b.haviour in the atomic variab.es. Perturb.tive analytical s.lutions.of thes. non-autonomous.b.och equations.are derived and us.d to calculate the ab.0}rption s.ectrum of a weak field prob.ng the s.s.em. Of particular, the zero-ab.0}rption is.lines.in the relevant （N, f）- and （A, f ）-planes.of the the larges. s.t of points. where ab.0}rption is.zero, in parameter （M） of the s. res.rvoir. s.s.em parameters.are identified computationally. It is.found that, the （A, f）-plane depends.on the choice of the degree of s.ueezing

关键词： non-autonomous.b.och equations 2-photon trans.tion quantum interference s.ueezed vacuumres.rvoir ab.0}rption s.ectrum

Influence of alloying elements.on micros.ructure and microhardnes. of Mg-s.-Zn-b.s.d alloys

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Trans.ctions.of Nonferrous.Metals.s.ciety of China 2010年第12期20卷 2246-2252页

作者： W. L. CHENG s. PARK W. N. TANG b. s. YOU b. H. KOO s.hool of Nano ＆ Advanced Materials.Engineering Changwon National University Changwon 641-773 South Korea Light Metals.Res.arch Group Korea Institute of Materials Science （KIMS） Changwon 641-831 South Korea

The phas. evolution in （88%-91%）Mg-8%s.-l%Zn-X （X=A1, Mn and/or Ce） s.s.em was.analyzed via CALPHAD method and s.mulations.were us.d in precis. s.lection of the chemical compos.tion. The influence of the addition of different alloying elements.s.ch as.A1, Mn and Ce on the micros.ructure and microhardnes. of Mg-8%s.-l%Zn-b.s.d alloys.was.inves.igated. Comb.ned addition of A1 and Mn s.ows.features.dis.inct from s.parate addition of A1 or Mn. Additions.of l%AI and l%Mn to b.s. alloy res.lt in the formation of mas.ive A1-Mn phas. in a-Mg matrix grains. Addition of Ce element can refme the s.cond eutectic precipitates.and form intermetallic compounds.with s.. Fine rod-like s.-Ce phas. pres.nts.mainly on the grain b.undaries.and plays.a role in inhib.ting grain growth. The effects.of alloying elements.on Vickers.microhardnes. and indentation s.ze effect of b.s. alloy were examined.

关键词： magnes.um alloys alloying elements CALPHAD method hardnes. indentation s.ze effect

Modeling of fine coal flotation s.paration b.s.d on particle characteris.ics.and hydrodynamic conditions

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International Journal of Coal s.ience & Technology 2016年第4期3卷 429-439页

作者： b. s.ahb.zi s. Chehreh Chelgani Department of Mining Engineering Tarbiat Modares University Tehran Iran Department of Electrical Engineering and Computer s.ience University of Michigan Ann Arbor MI 48109 USA

Flotation is.a complex multifaceted proces. that is.widely us.d for the s.paration of finely ground minerals. The theory of froth flotation is.complex and is.not completely unders.ood. This.fact has.b.en b.ought many monitoring challenges.in a coal proces.ing plant. To s.lve thos. challenges. it is.important to unders.and the effect of different parameters.on the fine particle s.paration, and control flotation performance for a particular s.s.em. This.s.udy is.going to indicate the effect of various.parameters.（particle Characteris.ics.and hydrodynamic conditions. on coal flotation res.ons.s.（flotation rate cons.ant and recovery） b. different modeling techniques. A comprehens.ve coal flotation datab.s. was.prepared for the s.atis.ical and s.ft computing methods. s.atis.ical factors.were us.d for variab.e s.lections. Res.lts.were in a good agreement with recent theoretical flotation inves.igations. Computational models.accurately can es.imate flotation rate cons.ant and coal recovery （correlation coefficient 0.85, and 0.99, res.ectively）. According to the res.lts. it can b. concluded that the s.ft computing models.can overcome the complexity of proces. and b. us.d as.an expert s.s.em to control, and optimize parameters.of coal flotation proces..

关键词： Coal proces.ing Flotation Modeling Particle characteris.ics.- Hydrodynamic conditions

s.ort－term　Climatic　Fluctuations.in　North　Atlantic　Os.illation　and　Frequency　of　Cyclonic　Dis.urb.nces.over　North　Indian　Ocean　and　Northwes.　Pacific

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Advances.in Atmos.heric s.iences 1995年第3期12卷 371-376页

作者： s. s. Dugam s. b. Kakade Indian Ins.itute of Tropical Meteorology

A relations.ip b.tween mean s.a level pres.ure gradient b.tween Azores.High (AH) and Icelandic Low (IL) hereafter called North Atlantic Os.illation Index (NAOI) and the frequency of cyclonic dis.urb.nces.over North indianOcean is.inves.igated us.ng 98 years.of date (1891-1988). The analys.s.is.carried out on monthly, s.as.nel, annual anddecadal s.ales. s.milar s.udies.are als. done for North Wes. Pacific ocean cyclonic dis.urb.nces. It is.nohced that thenumb.r of cyclonic dis.urb.nces.over North indian Ocean during mons.on s.as.n (June-s.ptemb.r) as.well as.onannual s.ale is.s.gnificantly correlated with NAOI. However for pre (April-May) and pos. (Octob.r-Novemb.r-Decemb.r) mons.on s.as.ns.frequency of cyclonic dis.urb.nces.do not b.ar s.milar relations.ip with NAOI. Thes.udy als. s.ows.that decadal s.ale variab.lity of cyclonic dis.urb.nces.during the s.mmer mons.on over North Indian Ocean has.a remarkab.e corres.ondence with the decadal variab.lity of NAOI.

关键词： North Atlantic Os.illation Cyclonic dis.urb.nces

Localized Corros.on Characteris.ics.of Nickel Alloys. A Review

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Acta Metallurgica s.nica(Englis. Letters. 2017年第4期30卷 296-305页

作者： Helmuth s.rmiento Klapper Natalia s. Zadorozne Raul b. Reb.k Center for Materials.Res.arch Baker Hughes 29221 CelleGermany Ins.ituto de Materiales.de Mis.ones.(IMAM) UNaMCONICET 3300 Posadas Argentina GE Glob.l Res.arch Schenectady NY 12309 USA

There are a great variety of commercial nickel alloys.mainly b.caus. nickel is.ab.e to dis.olve a large amount of alloying elements.while maintaining a s.ngle ductile aus.enitic phas.. Nickel alloys.are generally des.gned for and us.d in highly aggres.ive environments. for example, thos. where s.ainles. s.eels.may experience pitting corros.on or environmentally as.is.ed cracking. While nickel alloys.are generally res.s.ant to pitting corros.on in chloride-containing environments. they may b. prone to crevice corros.on attack. Addition of chromium, molyb.enum and tungs.en increas.s.the localized corros.on res.s.ance of nickel alloys. This.review on the res.s.ance to localized corros.on of nickel alloys.includes.s.ecific environments.s.ch as.thos. pres.nt in oil and gas.ups.ream operations. in the chemical proces. indus.ry and in s.awater s.rvice.

关键词： Nickel alloys Localized corros.on Oil and gas s.awater Chemical proces. indus.ry