简介:CdSthinfilmsweredepositedbytheionlayergasreaction(ILGAR)method.Structural,chemical,topographicaldevelopmentaswellasopticalandelectricalpropertiesofas-depositedandannealedthinfilmswereinvestigatedbyXRD,SEM,XPS,AFMandUV-VIS.Theresultsshowedthatthethinfilmsareuniform,compactandgoodinadhesiontothesubstrates,andthegrowthofthefilmsis2.8nm/cycle.Theevolutionofstructureundergoesfromthecubicstructuretothehexagonalonewithapreferredorientationalongthe(002)planeafterannealingat673K.AnamountofC,OandClimpuririescanbereducedbyincreasingthedryingtemperatureorbyannealinginN2atmosphere.ItwasfoundthatthebandgapoftheCdSfilmsshiftstohigherwavelengthafterannealingorincreasingfilmthickness.Theelectricalresistivitydecreaseswithincreasingannealingtemperatureandfilmthickness.
简介:Recoveryprocessesofsecondaryresourcesusuallyencounterproblemsbecauseofthediversecompositionsofwastes.Toenhancetheapplicabilityoftraditionalhydrometallurgicalprocesstowardsecondaryresources,theadjustmentofcomponentsisnecessary.Intraditionalhydrometallurgicalseparation,precipitationandcomplexationareextensivelyused.However,theircombinationasaspecificmetalseparationmethodhasnotyetbeenstudiedindetail.Thisapproachisverypromisingforsolvingproblemscausedbychangeablecomponentsduringrecyclingprocessesofsecondaryresources.Thispaperreviewstheeffectsofprecipitationandcomplexationinmetalseparationprocesses,andametalseparationmethodsystemof‘‘complexation–precipitation’’developedtoadjustthecomponentsofsecondaryresourcesisintroduced.
简介:Vanadiumnitridewassynthesizedbyone-stepmethodusingV2O5andcarbonblackasrawmaterialsinnitrogenatmosphere.ThephasesofdifferentreactionproductspreparedindifferentreactiontemperatureswereanalyzedbyX-raydiffraction(XRD),andthedynamicbehavioroftheprocessofsynthesizingvanadiumnitride(VN)byone-stepmethodwasstudiedwithnon-isothermalthermogravimetry.Themechanismfunctionandkineticparametersofreactionprocesswerecalculatedbythermalgravimetricanalyses(TGA),andthereactionrateequationwasestablished.TheXRDresultsshowthatforthesamplestestedwithminimalVNafterholdingfor4hat1273K,themainphaseofproductsisVNat1476K,whilesomevanadiumnitridestransformintovanadiumcarbidesagainover1573K.ItisfoundthatN2isbeneficialtostimulatereductionandproceedcarbonizationreaction,andthereductionandnitridationreactioncanoccursimultaneously.TheactivationenergyofpreparingVNbyone-stepmethodis104.005kJ·mol-1,andthefrequencyfactoris470.52at1280–1358K,and150.052kJ·mol-1and2.359104at1358–1426K,respectively.
简介:Fe(OH)3precursorsolwaspreparedbyasol-gelmethod.Theprecursorsolwasdippedontotheabsorbentcotton,andgelwasformedontheabsorbentcottontemplateafterthevolatilizationofmoisture.Fe2O3microtubulesweresynthesizedaftertheprocessofself-propagationorcalcination.Thephase,morphology,andparticlediameterofthesampleswereexaminedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM),andthemagneticpropertiesofthesamplesweremeasuredusingavibratingsamplemagnetometer(VSM).TheexternaldiametersofFe2O3microtubulesrangedbetween8and13μm,andthewallthicknessesrangedbetween0.5and2μm.ThetypeofthecalcinationmethodplaysasignificantroleindevelopingtheFe2O3phaseandthevariationinthemagneticpropertiesinthesol-geltemplatecomplexingmethod.γ-Fe2O3wassynthesizedbyaself-propagationmethod.However,α-Fe2O3wassynthesizedaftercalcinationat400°Cfor2h.Thecoercivityofthesamplessynthesizedbycalcinationat400°Cfor2hafterself-propagationwasfoundtoincreasesignificantly,therebypresentinghardmagneticproperties.
简介:nano石墨表/氧化铝composites被一个灵巧的受精减小过程在situ准备。composites的微观结构被X光检查衍射(XRD)分析,并且在减小以后的最后的阶段作文是艾尔2O3,金属Fe和石墨水晶。扫描电子显微镜学(SEM)图象证明Fe的粒子尺寸是大约20?nm,和石墨的lamellae厚度是大约30?nm。然后,绝缘的性质和composites的传导性的机制在0.01-1.00的频率范围试验性地被调查?由阻抗分析器的GHz。composites的介电常数的真实部分与Fe3+集中增加的结果表演,由于在Fe和艾尔23和薄片状的石墨形成的三维的网络。因此,悦耳的microtopography和nano石墨表/氧化铝composites的电的参数能被改变Fe3+集中认识到。
简介:Thewell-distributionspindleLiFePO4(LFP)nanoparticlesascathodeoflithiumsecondarybatteriesweresynthesizedbyasolvothermalreactionrouteatlowtemperature(180°C)inwhichtheascorbicacidwasusedasreducingagent.InordertoguaranteethatthepHvaluesofthermalsystemswerenotaffectedtoomuchandthereducibilityofthesystemwasenhancedatthesametime,glucosewaschosenasanauxiliaryreductantinthisreaction.TheobtainedpowderswerecharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),andlaserparticleanalyzer.Theresultsshowthatthecarbon-coateduniformspindleolivineLiFePO4/C-glucoseparticles(glucoseasauxiliaryreductant,LFP/C-G)arepreparedwiththesize500–600nmandwithoutanyimpurityphases.Theirelectrochemicalpropertieswereevaluatedbyelectrochemicalimpedancespectroscopy,cyclicvoltammetry,andgalvanostaticcharge/dischargetests.LFP/C-Ghasahigherconductivityandbetterreversiblecapabilitythancarbon-coatedLFP(LFP/C).ThehighestdischargecapacityofLFP/C-Gis161.3mAh·g-1at0.1Cand108.6mAh·g-1at5.0C,respectively.TheresultsimplythattheneatcrystalnanostructureofLFP/C-Ghasexcellentcapacityretentionandcyclingstability.Theaddingofglucoseisthekeyfactorforthewelldistributionandneatcrystalstructureofnanoparticles,thustheelectrochemicalperformancesofmaterialsareimproved.
简介:La-dopedSr-hexaferrite(Sr_(1-x)La_xFe_(12)O_(19))(x=0.05,0.10,0.15,0.20)nanopowderswithparticlesizerangingfrom80to110nmweresuccessfullysynthesizedbysol-gelauto-combustion.Thephaseformationtemperatureincreases,whiletheparticlesizedecreasesastheLadopingcontentgoesup.ThepartialsubstitutionofSr~(2+)byLa~(3+)resultsinthesuppressioneffectsonthegrowth-upofthecrystallitesandtheenhancementoftheelectronhoppingbetweenFe~(3+)withdifferentvalences,whichleadstotheimprovementinthedielectriclossandmagneticloss.Therefore,boththemicrowaveabsorbingabilitiesandabsorbingfrequencyrangesaretunedbyLa-doping.ThesynthesizedSr-hexaferritenanopowderswithdopingelementcontentof0.10demonstratethefinebroadmicrowaveabsorbingproperties.
简介:Auniformtransienttemperaturefieldmodelofelectricalcontactsoperationwasfoundbyanalyzingtheprocessofclosingarc→constrictionresistanceJouleheat→breakingarc.EssentialparametersofAg/La2NiO4electricalcontactmaterialfortransienttemperaturefieldcalculationwereobtainedthroughtestsofelectricalcontactexperimentalinstrumentunder18VDCindifferentcurrents,othercorrelationexperiments,andcalculationanalysis.Thefiniteelementmethodwasappliedtosolvethetransienttemperaturefield,andthefeaturesanddistributionofthetransienttemperaturefieldwereobtained.Theconditionofmaterialerosionandmasstransfercanbeforecastedbythosecalculationresults.ItisbeneficialtoresearchaboutthelifetimeofAg/La2NiO4electricalmaterial.
简介:EmployingLi2CO3,NiO,Co3O4,andMnCO3powdersasstartingmaterials,Li[Ni1/3Co1/3Mn1/3]O2wassynthesizedbysolid-statereactionmethod.Variousgrindingaidswereappliedduringmillinginordertooptimizethesynthesisprocess.Aftersuccessiveheattreatmentsat650and950℃,thepreparedpowderswerecharacterizedbyX-raydiffraction(XRD)analysis,scanningelectronmicroscopy,andtransmissionelectronmicroscopy.Thepowderspreparedbyaddingsalt(NaCl)asgrindingaidexhibitaclearR3mlayerstructure.ThepowdersbyothergrindingaidslikeheptaneshowsomeimpuritypeaksintheXRDpattern.Theformerpowdersshowauniformparticlesizedistributionoflessthan1μmaveragesizewhilethelattershowsawidedistributionrangingfrom1to10μm.EnergydispersiveX-ray(EDX)analysissshowthattheratioofNi,Co,andMncontentinthepowderisapproximately1/3,1/3,and1/3,respecively.TheEDXdataindicatenoincorporationofsodiumorchlorineintothepowders.Charge-dischargetestsgaveaninitialdischargecapacityof160mAh·g-1forthepowderswithNaCladditionwhile70mAh·g-1forthepowderswithheptane.