简介：转变地方法(TFM)被开发估计有任意的形状的水晶composites的各向异性的绝缘的性质和水晶包括的绝缘的性质，绝缘的轴与各向异性的水晶的那些其校长不同矩阵。包括形状引起的复杂边界值问题被介绍一个转变电场进水晶composites区域避免，并且有效各向异性的绝缘的回答以转变地被提出。而且，数字结果证明水晶composites的有效各向异性的绝缘的回答周期性地作为在包括和矩阵水晶材料的主要的绝缘的轴之间的旋转角度的功能变化。它被发现那更逍遥法外包括形状导致的包括体积部分有效各向异性的绝缘的回答上的深刻效果。

简介：Themixedmatrixmembranes(MMMs)weredevelopedbyincorporatinggraphiteoxide(GO)flakesfunctionalizedwithironoxide(Fe3O4)intoPebaxmatrix.ThePebax/Fe3O4-GOMMMswereusedtoseparateCO2/CH4andCO2/N2gasmixture.TheresultsshowedthattheMMMswithmagneticalignmentpresentedthebettergasseparationperformancethanthatofrandomarrangementofPebax/Fe3O4-GOmixedmatrixmembranes.ThereasonwasthattheFe3O4-GOflakesarrangedmagneticallyinthemembraneplayedamultipleroleinimprovingtheperformanceofMMMs.Firstly,undertheactionofthemagneticfield,themagneticalignmentofFe3O4-GOflakesinPebaxmatrixconstructedtheshortertransferpathforgasmolecule,increasingtheCO2permeability.Secondly,thehydroxylgroupsinGOflakesandthepresenceofFe3O4havestrongerbindingforceforwater,improvingtheCO2solubilityselectivity.Thirdly,thebetterinteractionbetweenthemagneticalignmentofGOcompositesandpolymermatrix,reducedtheinterfacedefects.Especially,theoptimumgasseparationperformsneewasobtainedattheFe3O4-GOflakescontentof3wt%inPebaxmatrixatverticalarrangementwithselectiv让yof47and75forCO2/CH4andCO2/N2,respectively,andCO2permeabilityof538Barrerat0.2MPaandroomtemperature.

简介：Theeffectivethermalconductivityofcompositeswithellipsoidalfillersisanalyzedbyusingahomogenizationmethodthatisabletorepresentthemicrostructureprecisely.Inthisstudy,variousparameterssuchasthevolumefraction,shape,anddistributionofthefillerarequantitativelyestimatedtounderstandthemechanismsofheattransferinthecomposite.First,thermalboundaryresistancebetweenresinandfillerisimportantforobtainingcompositeswithhigherthermalconductivity.Second,theanisotropyoftheeffectivethermalconductivityarisesfromcontactbetweenfillerinthecaseofellipsoidalfillerandproduceslowerthermalresistance.Finally,thefillernetworkandthermalresistanceareessentialfortheheattransferincompositesbecausethepathofthermalconductionisimprovedbycontactbetweenneighboringfillerparticles.

简介：Alkalimetalhydroxideandhydridecompositesystemscontainbothprotic(HbondedwithO)andhydridichydrogen.Theinteractionofthesetwotypesofhydridesproduceshydrogen.Theenthalpyofdehydrogenationincreasedwiththeincreaseofatomicnumberofalkalimetals,i.e.,-23kJ/molH2forLiOH-LiH,55.34kJ/molH2forNaOH-NaHand222kJ/molH2forKOH-KH.Thesethermodynamiccalculationresultswereconsistentwithourexperimentalresults.H2wasreleasedfromLiOH-LiHsystemduringballmilling.ThedehydrogenationtemperatureofNaOH-NaHsystemwasabout150℃;whereasKOHandKHdidnotinteractwitheachotherduringtheheatingprocess.Instead,KHdecomposedbyitself.Inthesethreesystems,NaOH-NaHwastheonlyreversiblehydrogenstoragesystem,theenthalpyofdehydrogenationwasabout55.65kJ/molH2,andthecorrespondingentropywasca.101.23J/(molH2K),sothetemperatureforreleasing1.0barH2wasashighas518℃,showingunfavorablethermodynamicproperties.TheactivationenergyforhydrogendesorptionofNaOH-NaHwasfoundtobe57.87kJ/mol,showinggoodkineticproperties.

简介：AseriesofxNiAl2O4/γ-Al2O3compositeswithvariousNicontentshavebeenpreparedviaone-steppartialhydrolysisofmetalnitratesaltsintheabsenceofsurfactantsandusedforcarbondioxidereformingofmethane.ThecharacterizationresultsdemonstratedthattheNiAl2O4/γ-Al2O3materialspossessedmesoporousstructuresofuniformporesizes;andtheNi2+ionswerecompletelyreactedwithaluminatoNiAl2O4spinelinthematricesusingN2sorption,XRD,TEM,andXPS.TheNiAl2O4/γ-Al2O3materialsexhibitedexcellentcatalyticpropertiesandsuperiorlong-termstabilityforcarbondioxidereformingofmethane.TheeffectsofNicontentontheintrinsicactivitiesandtheamountsofcokedispositionofthexNiAl2O4/γ-Al2O3catalystswerediscussedindetailforthecarbondioxidereformingofmethane.TheresultsrevealedthattheNiparticlesizesdidnotaffecttheintrinsicactivityofmetallicNi,butsmallerNiparticlescouldreducetherateofcokedeposition.

简介：Compositesofcarbonaerogelandgraphiteoxide(GO)weresynthesizedusingaself-assemblymethodbasedondispersiveforces.Theirsurfacewasmodifiedbytreatmentinhydrogensulfideat650and800℃.Thesamplesobtainedwerecharacterizedbyadsorptionofnitrogen,TA-MS,XPS,potentiometrictitration,andHRTEMandtestedascatalystsforoxygenreductionreactions(ORR)inanalkalinemedium.Thesynergisticeffectofthecomposite(electricalconductivity,porosityandsurfacechemistry)leadstoagoodORRcatalyticactivity.Theonsetpotentialforthecompositeofcarbonaerogelheatedat800℃isshiftedtoamorepositivevalueandthenumberofelectrontransferwas2e-atthepotential0.68VversusRHEanditincreasedto4e-withanincreaseinthenegativevaluesofthepotential.Anexcellenttolerancetomethanolcrossoverwasalsorecorded.

简介：Amine-silicacompositematerialsforpost-combustionCO2capturehaveattractedconsiderableattentionbecauseoftheirhighCO2uptakeatlowCO2concentrations,excellentCO2captureselectivityinthepresenceofmoisture,andlowerenergyrequirementsforsorbentregeneration.Thisreviewdiscussestherecentadvancesinamine-silicacompositesforCO2capture,includingadsorbentpreparationandcharacterization,CO2captureunderdryandmoistureconditionsatdifferentCO2partialpressures,sorbentregeneration,andstabilityaftermanycyclicsorption-desorptionruns.

简介：Theshiftinthepercolationthresholdofcompressedcompositeswasstudiedbya3Dcontinuumpercolationmodel.AMonteCarlo(MC)methodwasemployedinthesimulations.Thepercolationthresholdwasfoundtorisewiththecompressionstrain,whichcapturesthebasictrendincompression-inducedconductivityvariationfromtheexperiments.Bothfiberbendingandtextureformationcontributetothepercolationthreshold.Theresultssuggestthatfillerswithahighaspectratioaremoredesirableforsensorandelectricalswitchapplications.

简介：Objectives:Polymerizationshrinkageofdentalcompositesremainsamajorconcerninrestorativedentistrybecauseitcanleadtomicro-crackingofthetoothanddebondingatthetooth-restorationinterface.Theaimofthisstudywastomeasurethefull-fieldpolymerizationshrinkageofdentalcompositesusingtheopticaldigitalimagecorrelation(DIC)methodandtoevaluatehowthemeasurementisinfluencedbythefactorsinexperimentsetupandimageanalysis.Methods:Fourcommercialdentalcomposites,PremiseDentine,Z100,Z250andTetricEvoCeram,weretested.Compositewasfirstplacedintoaslotmouldtoformabarspecimenwithrectangular-sectionof4mmmm,followedbythesurfacepaintingtocreateirregularspeckles.Curingwasthenappliedatoneendofthespecimenwhiletheotherpartwerecoveredagainstcuringlightforsimulatingtheclinicalcuringconditionofcompositeindentalcavity.Thepaintedsurfacewasrecordedbyacharge-coupleddevice(CCD)camerabeforeandaftercuring.Subsequently,thevolumetricshrinkageofthespecimenwascalculatedwithspecialistDICsoftwarebasedonimagecrosscorrelation.Inaddition,afewfactorsthatmayinfluencethemeasuringaccuracy,includingthesubsetwindowsize,specklesize,illuminationlightandspecimenlength,werealsoevaluated.Results:ThevolumetricshrinkageofthespecimengenerallydecreaseswithincreasingdistancefromtheirradiatedsurfacewithaconspicuousexceptionbeingthecompositePremiseDentineasitsmaximumshrinkageoccurredatasubsurfacedistanceofabout1mminsteadoftheirradiatedsurface.Z100hadthegreatestmaximumshrinkagestrain,followedbyZ250,TetricEvoCeramandthenPremiseDentine.Largersubsetwindowsizemadetheshrinkagestraincontoursmoother.Butthecostwasthatsomedetailsintheheterogeneityofthematerialwerelost.Verysmallsubsetwindowsizeresultedinalotofnoiseinthedata,makingitdifficulttodiscernthegeneralpatterninthestraindistribution.Speckle

简介：AKondo-likeeffect,namely,theupturnofresistivityatlowtemperatures,isobservedinperovskitemanganitewhennonmagneticinsulatorsaredopedassecondaryphase.Inthispaper,thelow-temperatureresistivityupturneffecthasbeenarguedtooriginatefrominterfacialmagneticphasereconstruction.HeisenbergspinlatticeshavebeensimulatedusingtheMonteCarlomethodtorevealphasecompetitionaroundsecondaryphaseboundary,namely,manganite-insulatorboundarythatbehaveswithaweakantiferromagnetictendency.Moreover,theresistornetworkmodelbasedondouble-exchangeconductivemechanismreproducesthelow-temperatureresistivityupturneffect.Ourworkprovidesareasonablephysicalmechanismtounderstandthenoveltransportbehaviorsinmicrostructuresofcorrelatedelectronsystems.

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简介：Two-dimensional(2-D)BiVO4nanosheets-graphene(GR)compositeswithdifferentweightadditionratiosofGRhavebeenpreparedviaafacilewetchemistryprocess.X-raydiffraction(XRD),Ramanspectra,X-rayphotoelectronspectra(XPS),UV-visdiffusereflectancespectra(DRS),field-emissionscanningelectronmicroscopy(FE-SEM),transmissionelectronmicroscopy(TEM),nitrogenadsorption-desorption,transientphotocurrentresponseandphotoluminescence(PL)spectrawereemployedtodeterminethepropertiesofthesamples.ItisfoundthatBiVO4nanosheetscouldpavewellonthesurfaceofgraphenesheets.BiVO4nanosheets-GRcompositeswithaproperadditionamountofGRexhibitedhigherphotocatalyticactivitythanbareBiVO4nanosheetstowardliquid-phasedegradationofrhodamineB(RhB)andmethylorange(MO)undervisiblelightirradiation.TheenhancementofphotocatalyticactivitiesofBiVO4nanosheets-GRcompositescanbeattributedtotheeffectiveseparationofphotoexcitedelectron-holepairs.Thisworknotonlyprovidesasimplestrategyforfabricatingspecific2-Dsemiconductor-2-DGRcomposites,butalsoopensanewwindowofsuch2-Dsemiconductor-2-DGRcompositesasvisiblelightphotocatalyststowardanimprovedvisiblelightphotoactivityinpurifyingpollutedwaterresources.

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简介：Herein,wereportthevictorioussynthesisofmetal-organicframeworks(MOFs)onTiO2nanotubes(NTs)usingalayer-by-layer(LbL)approach.HighlycrystallineandhomogenousthinfilmsofMOFsweregrownandcharacterizedusingXRD,SEM,FT-IRandUV/Visspectroscopy.Moreover,theutilizationoftheMOFfilmsassensitizerswasprobedinbespokeGraetzeltypeliquidjunctionsolarcells.TheconstructedcellperformancerevealedanIscof1.16mAcm–2,Vocof0.63V,FFof0.33,andEffof0.42%.Further,pumpprobetransientlaserspectroscopywasperformedtoinvestigatetheenergyandchargetransferdynamicsoftheMOFs/TiO2NTsinterface.Theresultsindicated86%injectionefficiency.Theultrafastpump-probespectroscopyallowstheinvestigationofthisprocessandthedifferencesbetweenMOFs.ItalsoshowedthattherelaxationoftheMOFchromophoresisincompetitionwithelectroninjectionintheTiO2motif.Thusthisstudyprovidesanewinsightintoelectrontransferfromphotoexcitedmetal-organicframeworks(MOFs)intotitaniumdioxide.