简介：Theeffectoflanthanumiononmembranepermeabilityofcornrootsegmentisstudied.ResultsshowsthattreatmentoftherootsegmentswithLaCl3·7H2Ocandecreasetheionleakageoftheroottissue.Theleakagedecreaseshyincreasingtheconcentrationoflanthanum,andtheconcentrationhasnofurtherdependenceonionleakagesabove25μmol/L.Aftertreatingtheroottissueforonehourwithlanthanumion,theamountofleak-agehaslineardependenceontimewithinthefirst2handaftertwohourstheleakageincreases.Theionleakageofthetissuedependesonthetimeoflanthanumtreatment.Whenthedurationoftreatmentisprolonged,theleakagedecreasesrapidlyandtheleakagereachesaminimumat30minutes.Otherrareearthelementscanalsodecreaseionleakage.Thereisnosignificantdifferenceintheionleakageamongtheseelements.

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简介：InordertosensitizetheluminescenceofEu3+ionsinheavymetalglass,zincleadborateglasssamplescontainingvariousconcentrationsofEu3+andTb3+ionswerepreparedtostudytheTb3+toEu3+non-radiativeenergytransferphenomena.EnergylevelstructuresofTb3+andEu3+ionswereplottedtoshowtheexcitationandenergytransferroutes.EfficientenergytransferfromTb3+toEu3+wasobservedandstudiedqualitativelyintermsofdopingconcentrations.Thesensitizationturnedouttobelesseffectivethanexpected.FurtherstudiestocharacterizetheoxidationofTb3+intotetravalentstateandtoexaminethemechanismofenergytransferareproposed.

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简介：LanthanidedopedNaYF4microcrystalsweresynthesizedviaafacilehydrothermalmethod.MulticolorupconversionluminescencewasobservedinNaYF4microcrystalsdopedwithYb3+/Er3+,Yb3+/Tm3+,andYb3+/Er3+/Tm3+undertheexcitationof980nminfraredlight.Importantly,theexcitationpowerdensitydependenceofupconversionemissionintensityindicatedclearlytheenergytransferfromTm3+toEr3+ionsundertheexcitationoflowpowerdensity(5×102–9×102W/cm2).Meanwhile,theinverseenergytransferfromEr3+toTm3+ionsundertheexcitationofrelativelyhigherpowerdensity(4.1×104–4.9×104W/cm2)wasalsorevealed.ThiswasadirectevidenceforreversibleenergytransferbetweenEr3+andTm3+ions.Undertheexcitationofhighpowerdensity(4.1×104–4.9×104W/cm2),darksensitizerswerealsomotivatedsothatthebottleneckeffectofhighconcentrationYb3+iondopingwasbroken.ThiswasthemainreasonforrealizinghighupconversionefficiencyofthesampleswithheavydopingofYb3+ion.

简介：Ba0.85Ca0.15Ti0.9Zr0.1O3(BCTZ)lead-freepiezoelectricceramicsco-dopedwithCeO2(x=0.1wt.%,0.2wt.%,0.3wt.%,0.4wt.%,0.5wt.%)andLi2CO3(0.6wt.%)werepreparedbyconventionalsolid-statereactionmethod.InfluenceofCeO2dopingamountonthepiezoelectricproperties,dielectricproperties,phasecompositionandmicrostructureofpreparedBCTZlead-freepiezoelectricceramicsdopedwithLi2CO3wereinvestigatedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM)andotheranalyticalmethods.TheresultsshowedthatthesinteredtemperatureofBCTZlead-freepiezoelectricceramicsdopedwithCeO2decreasedgreatlywhenLi2CO3dopingamountwas0.6wt.%;apureperovskitestructureofBCTZlead-freepiezoelectricceramicsco-dopedwithLi2CO3andCeO2andsinteredat1050°Ccouldalsobeobtained.Thepiezoelectricconstant(d33),therelativepermittivity(εr)andtheplanarelectromechanicalcouplingfactor(kp)ofBCTZceramicsdopedwithLi2CO3increasedfirstlyandthendecreased,thedielectricloss(tanδ)decreasedfirstlyandthenincreasedanddecreasedatlastwhenCeO2dopingamountincreased.TheinfluenceofCeO2dopingonthepropertiesofBCTZlead-freepiezoelectricceramicsdopedwithLi2CO3werecausedby'softeffect'and'hardeffect'piezoelectricadditiveandcausinglatticedistortion.WhenCeO2dopingamount(x)was0.2wt.%,theBCTZceramicsdopedwithLi2CO3(0.6wt.%)andsinteredat1050°Cpossessedthebestpiezoelectricpropertyanddielectricpropertywithd33of436pC/N,kpof48.3%,εrof3650,tanδof1.5%.

简介：FluorescencespectraofSm2+andEu2+→Sm2+energytransferwerestudiedinSrB4O7.Thereappearsonlyfluorescencefrom5D0transitionofSm2+at77K.Thevibroniclinesassociatedwith5D0→7F0transitionwereobserved.Thethermalpopulationtoupperstatesof5D1and4f5dlevelsfrom5D0givesriseto5D1→7FJand5d→4fradiativetransitionsofSin2+athighertemperature.

简介：Pt-freecounterelectrode（CE）composedofLa2MoO6（La2O3-MoO3）wassuccessfullysynthesizedbysimplepyrolysisoflanthanumacetate（C6H9O6La·xH2O）andhexaammoniumheptamolybdatetetrahydrate(（NH4）6Mo7O24·4H2O).Furthermore,threeproportionscompositescatalystsofLa2MoO6@MWCNTsbasedonLa2MoO6andmultiwallcarbonnanotubes（MWCNTs）werepreparedandcharacterizedasPtfreecatalystforCEindye-sensitizedsolarcells（DSSCs）.ThemorphologyandstructureofLa2MoO6@MWCNTscompositesweredeterminedbyscanningelectronmicroscopy,transmissionelectronmicroscopeandX-raydiffraction.TheelectrochemicalperformanceofLa2MoO6@MWCNTscompositecatalystsforCEswasdeterminedbyphotocurrent-voltagemeasurements,cyclicvoltammetry,electrochemicalimpedancespectroscopy,andTafelpolarization.Thepowerconversionefficienciesof4.68%,4.87%and5.06%areobtainedforLa2MoO6:MWCNTswiththemassratiosof5:1,3:1and1:1towardsthereductionofI3-toI-underthesameconditions,respectively,whicharesuperiortothoseofMWCNTs（3,94%）andLa2MoO6（1.71%）electrodes.TheexperimentalresultsrevealthatthepresenceofMWCNTsresultsinanaugmentedactivecatalyticsurfaceareaandenhancedchargetransferfromCEtotheelectrolyte.

简介：Cr的Nanopowder:Cr的GGG和nanopowder，Nd:有从0.1at.%到1.5at.%的Cr3+的不同集中的GGG被大音阶的第五音胶化方法用醋酸和乙烯乙二醇综合。热gravimetric分析和微分扫描热量测定(TGA-DSC)，X光检查衍射(XRD)和光致发光光谱学被用来描绘粉末。当在1000点对待时，雏晶尺寸是大约58nm?????????????????猯灵?匠?猼'T资???猼灵?????????猯'T??猼灵????￣?????猯'T????猯灵??猼'T?????吗????????????????‵渠????????浮？？