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简介：Nano-sizedhexagonalmagnesiumhydroxide（Mg（OH）2）withgooddispersibilitywassynthesizedbyadoubleinjection-hydrothermalmethod,utilizingpolyvinylpyrrolidone（PVP）asanadditiveandwithoptimizedprocessingparameters.SEMandBETanalysisshowedthatthemeanparticlesizeandspecificsurfaceareaoftheMg（OH）2particleswere174nmand50.77m2/g,respectively.TheFT-IRspectraandtheXRDpatternsshowedthatPVPwasadsorbedonthesurfaceoftheMg（OH）2crystal,thuseffectivelylimitingparticleagglomerationandhinderingcrystalgrowthalongthe（101）plane.TGAshowedadecreaseinthedecompositiontemperatureandanincreaseintheweightlossoftheMg（OH）2particlesduetoadditionofPVP.

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

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简介：Inthisstudy,thecharacterizationandmodificationofwastemagnesiumchips(WMCs),whichwereproducedbyplasticmoldinginagoldmanufacturingfactoryandareusedasMg-richintermetalliccompositesinstoringhydrogen,werediscussedindetail.WMCswereanalyzedusingX-raydiffraction(XRD),X-rayfluorescence(XRF)spectroscopy,differentialscanningcalorimetry(DSC),scanningelectronmicroscopy(SEM),andBrunauer-Emmett-Teller(BET)analysistocharacterizethematerials’structuralproperties.Mechanicalmilling,organictreatment,andinorganicsaltadditionwerecarriedouttomodifytheWMCs’surfacetoprepareMg-richintermetalliccompositesforstoringhydrogen.Themodifiedsampleswereanalyzedusinghigh-pressurevolumetricanalysestocalculatetheirhydrogenstoragecapacity.TheauthorsconcludethatmodifiedWMCwaspromisingasanMg-richintermetalliccompositethatwassuitableforuseinhydrogenstoragewitha4.59wt%capacityat320Cunderahydrogenpressureof60bar.

简介：Inthealloywithsolutecontenthigherthanthelimitingsolubility,thesoluteatomsthathavefailedtodissolvewillprecipitatefromthesolidsolutionandformprecipitations.Inthisstudy,thePortevin-LeChatelier(PLC)effectsinannealed5456and5052aluminumalloyswithdifferentprecipitationcontentshavebeeninvestigatedunderdifferentappliedstrainrates.TheresultssuggestthatprecipitationshavesignificanteffectonthePLCeffectandthemoretheprecipitationsare,thegreaterthe...

简介：Acleanmethodforpreparinglayereddoublehydroxides(LDHs)hasbeendeveloped,featuredbyusingthehydroxidesoftwodifferentmetalsasstartingmaterialsbyatom-economicreactions.Thereactionswerecarriedoutunderhydrothermalconditionsineitherahighpressureautoclaveoramicrowavedigester.Thecompositions,structuralparametersandthermalbehavioroftheresultingLDHsareverysimilartothoseofmaterialsproducedbyusingtheseparatenucleationandagingsteps(SNAS)method.Themajoradvantageofthenewmethodisthatnoby-productisproduced,sothatfiltrationandwashingprocessesareunnecessary.Theconsequentreductioninwaterconsumptionisbeneficialtotheenvironment.

简介：ThecharacteristicsofsuspendedsedimentimagecanbereflectedbythecoefficientsofbiorthogonalwavelettransformofCDF(2,2).Basedonthepowerdistributionindifferentscales,anadaptivealgorithmisproposedinthispaper,wherebythecoefficientsareadjustednon-linearly.Theparticleinformationcanbewellretainedwhiletheuselessbackgroundisremoved.Inthisway,satisfactorybinaryimagecanbeobtainedforfurtheranalysisofthesedimentparticle.

简介：TiO2@ZrO2@Y2O3:有coremultishell结构的Eu3+合成粒子通过layer-by-layer(LBL)的联合被综合自己组装方法和一个solgel过程。获得的样品与扫描电子被描绘显微镜学(SEM)，传播电子显微镜学(TEM)，X光检查光电子光谱学(XPS)，X光检查衍射(XRD)，和荧光spectrophotometry。结果证明合成粒子有coremultishell结构，球形的形态学，和狭窄的尺寸分布。TiO2核心上的ZrO2层的存在能有效地阻止在TiO2核心和Y2O3壳之间的反应；为在在TiO2@ZrO2@Y2O3的TiO2核心和Y2O3壳之间的反应的温度:Eucoremultishell黄磷能被300提高

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

简介：PureAl2O3-2SiO2powderswerepreparedbysol-gelandcoprecipitationmethods,andtheiralkaliactivationreactivitieswerecompared.Thealkali-activationreactivityofthepowderpreparedbythesol-gelmethodwashigherthanthatofthepowderpreparedbythecoprecipitationmethod.Thepowderswereinvestigatedby27AIand29Simagic-anglespinningnuclearmagneticresonancespectroscopy（MASNMR）tounderstandtherelationshipbetweentheirstructureandalkali-activationreactivity.The27AlMASNMRdatashowedthatthefive-coordinateAIcontentofthepowderpreparedbythesol-gelmethodwashigherthanthatofthepowderpreparedbycoprecipitation.Thehighercontentoffive-coordinateAlcorrespondedtohigheralkali-activationreactivity.The29SiMASNMRdatashowedthatforthepowderpreparedbythesol-gelmethod,siliconwasreplacedbyaluminumatsecondarycoordinationsitesofthecentralSiatomsduringcalcination.However,forthepowderpreparedbysingle-batchcoprecipitation,themainchangewasfromalowdegreeofpolycondensationtoahighdegreeofpolycondensation.

简介：HomogeneousNi2+-dopedtitaniagelwassynthesizedbyasol-gelprocess,andthexerogelwasthenobtainedthroughaginganddrying,leadingtotheformationofNi/TiO2nanocompositeafterheattreatmentunderasuitablereducingatmosphere.TheresultingnanocompositewascharacterizedbyTGA-DSC,TEM,XRDandBETmethods.Theresultsshowthatthestructureandgrainsizeofthenanocompositescouldbemanipulatedbyalteringtheheat-treatmentconditions,andthatthenanocompositepossessesamesoporousstructurewithaporeradiusofca.28nmandaspecifictheanatase-rutilephasetransformation.

简介：DrivenbycuriosityaboutpossibleflightoptionsfortheChang’e-2spacecraftafteritremainsattheSun-EarthL2point,effectiveapproachesweredevelopedfordesigningpreliminaryfuel-optimalnear-Earthasteroidflybytrajectories.Theapproachesincludetheuseofmodifiedunstablemanifolds,gridsearchofthemanifolds’parameters,andatwo-impulsemaneuverfororbitalphasematchingandz-axisbiaschange,andaredemonstratedtobeeffectiveinasteroidtargetscreeningandtrajectoryoptimization.Asteroidflybysareexpectedtobewithinadistanceof2×107kmfromtheEarthowingtotheconstrainedEarth-spacecraftcommunicationrange.Inthiscase,thespacecraft’sorbitalmotionissignificantlyaffectedbythegravitiesofboththeSunandtheEarth,andtherefore,theconceptofthe"heliocentricoscillating-Keplerorbit"isproposed,becausetheclassicalorbitalelementsoftheflybytrajectoriesreferencedintheheliocentricinertialframeoscillatesignificantlywithrespecttotime.Theanalysisandresultspresentedinthisstudyshowthat,amongtheasteroidswhoseorbitsarethemostaccuratelypredicted,"Toutatis","2005NZ6",or"2010CL19"mightbeencounteredbyChang’e-2inlate2012or2013withtotalimpulseslessthan100m/s.

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.

简介：Thecoordinationpolymer,(Nd(H2O)5)2(2,6-AQDS)3·2H2Owhere2,6-AQDS=2,6-anthraquinonedisulfonate,hasbeensynthesisedviaahydrothermalroute.Structurally,itconsistsoflayersofmonomericNdpolyhedrawhicharelinkedby2,6-AQDSanionsformingapolymeric,three-dimensionalnetwork.EachNdatomisninecoordinate,bondingtofivewatermoleculesandtofouroxygenatomsfromfour2,6-AQDSanionswhichinturnpillarthelayersbybridgingtwoNdatomsinonelayer,andcoordinatingtoasingleNdintheother.

简介：NanocrystallineSnO2wassynthesizedbydirectmixingandgrindingofSnCI4-5H2OandNaOHatroomtemperature,followedbycalcinationatdifferenttemperaturesfordifferenttimesinair.ProductsampleswerecharacterizedbyX-raydiffractionandtransmissionelectronmicroscope,revealingthattheamorphousprecursorSnO2wastransformedtocrystalsat200℃for3h,andthattheaverageparticlesizeincreaseduponraisingthecalciningtemperatureorprolongingthecalciningtime.Themechanismofthephasetransformationoftheproductsisdiscussed.

简介：连贯的多角形的粒子的二维的分离元素模型(DEM)模拟被开发了估计点来源颤动的利益在楔形的hoppers导致流动。使用的particleparticle相互作用模型基于一个多接触原则。没有颤动，学习的第一部分在严肃下面调查了粒子分泌物决定批评的孔尺寸(Bc)就作为粒子形状的功能支撑流动。多角形形状的粒子比圆形的粒子需要一个更大的孔，这被显示出。当粒子顶点的数字增加，Bc减少，这也被显示出当粒子顶点的数字增加。圆形的粒子的增加以一种线性方式支持多角形的流动。学习的第二部分证明那颤动能提高流动，有效地减少Bc。模型表明了震荡器地点(高度)的重要性，与在提高的以前的连续统模型结果，和颤动振幅一致流动。

简介：Uniformlysizedα-Fe2O3hexagonalplateletsweresynthesizedbyahydrothermalprocessusingFe(OH)3suspensionandlargeamountofNaOH.ThereactionproductswerecharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),selectedareaelectrondiffraction(SAED),andavibratingsamplemagnetometer(VSM).Theresultsshowthatthehexagonalplateletsarefine,monodisperseandconsistingofsingle-crystals.Themagnetichysteresis(M-H)curveofthesamplesmeasuredatroomtemperatureindicatesthattheα-Fe2O3micro-plateletsexhibitferromagneticbehaviorswithrelativelylowcoercivity.