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简介：Duetotheirsize-dependentpropertiesandflexibleprocessingchemistry(Alivisatos,1996),monodispersednanocrystalshaveattractedconsiderableattentionfortheirdistinguishedroleinfundamentalstudiesandtechnicalapplications.AlthoughmuchhasbeenreportedonfabricationofmonodispersedinorganicnanocrystalssuchasFe2O3,CdSe,PbSeandZrO2(Peng&Peng,2002;Zhuetal.,2002;Niederbergeretal.,2002;Pangetal.,2001),littlepublishedonthepreparationofBaSO4nanocrystalsandtheircrystalsizeandmorphologywhichaffecttheirperformanceinapplication.PolymeradditiveswithcomplexfunctionshavebeenusedastemplatestodirectorientednucleationandgrowthofBaSO4(Xiaoetal.,2001;Yuetal.,2002;Summersetal.,2002),asanewclassoffunctionalpolymers,theso-calleddouble-hydrophilicblockcopolymers,designedtocontrolthemorphologyofBaSO4(Colfenetal.,2002),includingtheirnanofiberssynthesizedinAOTmicroemulsion(Li&Mann,2000).ThoughsomuchresearchhasbeendevotedtocontrollingtheBaSO4morphologies,thepresentnotewillreportonthesynthesisofBaSO4nanocrystalswithsizecontrolling.

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简介：W，N共同做TiO2nanoparticles被一个solgel方法综合。准备样品被X光检查衍射(XRD)描绘，域排放扫描电子显微镜学(FE-SEM)，传播电子显微镜学(TEM)，Fourier变换红外线的光谱学(英尺红外)，X光检查光电子光谱学(XPS)和弥漫的反射spectrophotometry(医生)。结果证明共同做的光催化剂是有22.5nm的最小的粒子尺寸的实质上一致的球形的粒子。比作未做的TiO2，N-TiO2和P-25，W的吸收边，N共同做转移到更长的波长的TiO2和它为在Xe灯(350W)下面的甲基橘子(瞬间)的降级的photocatalytic活动更高。

简介：NanofluidswerepreparedbydispersingCunanoparticles(~20nm)inn-tetradecanebyatwo-stepmethod.Theeffectivethermalconductivitywasmeasuredforvariousnanoparticlevolumefractions(0.0001-0.02)andtemperatures(306.22-452.66K).TheexperimentaldatacompareswellwiththeJangandChoimodel.Thethermalconductivityenhancementwaslowerabove391.06Kthanforthatbetween306.22and360.77K.Theinterfacialthermalresistanceincreasedwithincreasingtemperature.Theeffectivethermalconductivityenhancementwasgreaterthanthatobtainedwithamoreviscousfluidasthebasemediaat452.66KbecauseofnanoconvectioninducedbynanoparticleBrownianmotionathightemperature.

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简介：针对甲酸乙酯(H(CO)OCH2CH3)与羟基自由基(OH)的反应动力学展开了理论与实验研究.在理论方面,首先通过量化计算得到了在M06-2x/ma-TZVP水平下准确的反应势能面,随后利用多结构-扭转(multi-stucturetorsionMS-T)方法对转动非谐效应进行了研究,获得了非谐校正系数,最后基于传统过渡态理论并考虑Eckart隧穿效应获得了200~2000K温度范围的反应速率常数.在实验方面,开展了激波管实验来测定H(CO)OCH2CH3与OH的反应速率常数,基于激光吸收光谱技术探测OH自由基306.7nm的吸收线,并对反射激波后高温反应过程的OH浓度变化进行测量,从而获得了900~1321K温度范围的反应速率常数,并论证了理论计算结果的合理性与准确性.

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简介：Well-dispersedBaSO4nanoparticlesweresynthesizedinthepresenceofsodiumpolyacrylate（PAAS）byasimpleprecipitationmethod,withBaCl2and（NH4）2SO4asreactants.ThedifferentrolesperformedbyPAASinthesynthesisofBaSO4nanoparticleswereinvestigatedusingX-raydiffractometry,Fouriertransforminfraredspectroscopy,andtransmissionelectronmicroscopy.TheresultsindicatethattheassynthesizedBaSO4nanoparticlesweresphereswithanaveragediameterof30nmandthattheirsurfaceswereaffectedbythePAAS.Underatypicalprocedureemployed,PAASreactedwithBaCl2toyieldanintermediate,servingasacontrolreleasingagentandseparatingthenucleationandcrystalgrowthprocessesoftheBaSO4nuclei.DuringformationoftheBaSO4nanospheres,theintermediateslowlydissolvedandreleasedbariumandpolyacrylateions,inhibitingthegrowthandaggregationofnewlyformedBaSO4seedsandresultinginparticlesofnarrowdiameterdistributionandimproveddispersibility.Moreover,thesepolyacrylateionsfurthermodifiedthesurfacesoftheBaSO4nanoparticles.

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简介：Fatiguepropertiesofage-hardenedAlalloy2017-T4underultrasonicloadingfrequency(20kHz)wereinvestigatedandcomparedwiththeresultsunderconventionalloadingofrotatingbending(50Hz).Thegrowthofacrackretardedatabout500μminsurfacelengthunderultrasonicloading,whileatabout20μmunderrotatingbending.Althoughstriationsbeingatypicalfracturemechanismwereobservedunderconventionalloading,mostoffracturesurfacewascoveredwithmanyfacetsunderultrasonicloading.Thesefacetswerealsoobservedunderrotatingbendinginnitrogengas.Thedifferenceingrowthmechanismdependingontheloadingfrequencyandtheretardationofacrackgrowthunderultrasonicloadingmaybecausedbytheenvironmentatthecracktipduetohighcrackgrowthrateunderultrasonicloading.

简介：TheinfluenceofNa2SO4ontheformationofZnOwhiskerswasinvestigatedinthispaper.ZnOwhiskerswithaspectratiosofupto50weresynthesizedbydissolvingε-Zn（OH）2precursorinNaOH/Na2SO4solutionatroomtemperature,followedbyagingoftheresultingsolutionat140℃for6h.Fouriertransforminfraredspectroscopy,Ramanspectroscopy,andX-rayphotoelectronspectroscopyanalysesrevealedthatSO42-ionswereprimarilyadsorbedonthe（100）planeoftheZnOwhiskersviaanouter-spherecomplexconfiguration（O-H…O）,therebypromotingtheone-dimensionalgrowthofZnOwhiskersalongthec-axis.

简介：有从30～80nm的尺寸的Fe3O4nanoparticles被湿milling铁粉末在一家行星的球工厂综合。阶段作文和同样综合的产品的形态学被X光检查衍射(XRD)测量，扫描电子显微镜学(SEM)和传播电子显微镜学(TEM)。NanosizedFe3O4粒子被湿milling准备金属性的铁粉末(?200网孔，99%)在与不锈钢装备的一家行星的球工厂，使用的小瓶与50:1并且以300rpm的旋转速度的ball-to-powder团比率在提取的水下面熨球。在这个方法的铁球的使用在Fe3O4formation起了一个关键作用。现在的技术简单，这个过程是容易的执行。

简介：Lithium-aluminum-cobalt-nickeloxideLiAlxCoyNi1xyO2particles,generallyusedascathodeoflithiumbattery,werepreparedbychemicalcoprecipitationfromanaqueoussolutionofLiOH,Al(NO3)3,Co(NO3)2andNi(NO3)2withNH4OH.XRD,SEMandFTIRwereusedtoexaminetheeffectofnickelcontentontheproduct.FTIRpatternsshowedthatincreaseinnickelcontentdecreasedtheabsorptionstrengthofthepeakofspinelstructureoftheproduct,attributedtotheoccupationbynickelinthealuminumsites.Particlesizeandelectricalpropertiesofthelithium-aluminum-cobalt-nickeloxide(abbreviatedasLACNO)particleswerealsodetermined.

简介：The(2+1)-dimensionalBKPequationintheHirotabilinearformisstudiedduringthiswork.WronskianandGrammiantechniquesareappliedtotheconstructionofWronskianandGrammiansolutionsofthisequation,respectively.ItisshownthatthesesolutionscanbeexpressedasnotonlyPfaffiansbutalsoWronskiansandGrammians.

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简介：Octahedron-likeBaMoO4microcrystalsweresynthesizedbytheco-precipitationmethodatroomtemperatureandprocessedinmicrowave-hydrothermalat413Kfordifferenttimes(from30minto5h).ThesemicrocrystalswereanalyzedbyX-raydiffraction(XRD),field-emissiongunscanningelectronmicroscopy(FEG-SEM)andtransmissionelectronmicroscopy(TEM).XRDpatternsshowedthatthismaterialpresentsatetragonalstructurewithoutthepresenceofdeleteriousphases.FEG-SEMandTEMmicrographsrevealedthattheBaMoO4microcrystalspresentanoctahedron-likemorphologywithagglomeratenatureandpoly-disperseparticlesizedistribution.Thesemicrographsalsoindicatedthatthemicrocrystalsgrowalongthe[001]direction.Theobservedcrystallographicplanesinthesestructuresweremodeledcomputationallyandacrystalgrowthmodelwasproposedinordertoexplainthemorphologicalchangesasafunctionofprocessingtime.

简介：TiO2nanoparticlesweresynthesizedbyahomogeneouscontrolledprecipitationmethodusingindustrialtitaniumsulfate(Ti(SO4)2).TheobtainedpowderswerecharacterizedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM),Fouriertransforminfraredspectroscopy(FTIR)andICPplasmaspectrometer.EDTAwasusedascomplexingagenttoimprovethepurityandtheformationofTiO2nanoparticles.Experimentalresultsindicatedthatthehigh-purityTiO2nanoparticleswere20nminmeansizeandnearlymonodispersed.

简介：The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.

简介：Inthispaper,ahigh-orderfinite-volumeschemeispresentedfortheone-dimensionalscalarandinviscidEulerconservationlaws.TheSimpson’squadratureruleisusedtoachievehigh-orderaccuracyintime.TogetthepointvalueoftheSimpson’squadrature,thecharacteristictheoryisusedtoobtainthepositionsofthegridpointsateachsub-timestagealongthecharacteristiccurves,andthethird-orderandfifth-ordercentralweightedessentiallynon-oscillatory(CWENO)reconstructionisadoptedtoestimatethecellpointvalues.Severalstandardone-dimensionalexamplesareusedtoverifythehigh-orderaccuracy,convergenceandcapabilityofcapturingshock.