简介:Ba1.0Co0.7Fe0.2Nb0.1O3-δ(BCFN)oxidewithperovskitecubicstructurewassynthesizedbysolidstatereactionmethod.CO2corrosionofBCFNmembranewasinvestigatedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),diffusereflectanceinfraredFouriertransformedspectroscopy(DRIFT)andX-rayabsorptionfinestructurespectroscopy(XAFS).Cobalt(Co)K-edgeabsorptionspectraofBCFNannealedinCO2revealthattheoxidationstatesofCoinallthesampleswerelargerthan+3andtheydecreasedwiththeincreaseofcalcinationtime.At800℃,1%CO2introducedintoHecouldspeedupthereductionofCocationsincomparisonwithpureHe.Inaddition,sulfateionsinthebulkofBCFNmembranepreferredtomigratetothesurfaceunderCO2calcinationandformmonoclinicBa(CO3)0.9(SO4)0.1besidesorthorhombicwitherite.Moreover,SEMresultsindicatethatthenucleationandgrowthofcarbonatesgrainsstartedatthegrainboundaryofthemembrane.
简介:TheeffectofrapidsolidificationonstructureandelectrochemicalperformanceoftheLaNi4.5Co0.25Al0.25hydrogenstoragealloywasinvestigatedbyX-raypowderdiffractionandasimulatedbatterytest,includingmaximumcapacity,cyclingstability,self-discharge,andhigh-ratedischargeability(HRD).Allthemelt-spunalloysweresingle-phasewiththeCaCu5-typestructure(spacegroupP6/mmm).Incomparisontotheas-castalloy,therapidlyquenchedalloysmanifestedanimprovedhomogeneityofcompositionandexpandedlatticeparameters.Theelectrochemicalmeasurementsshowedthattheactivationproperty,cyclingstabilityandself-dischargeofthealloyelectrodeswerealsoimprovedfortherapidsolidifiedalloys.TheHRDoftheas-castalloywasbetterthanthoseofalltherapidlysolidifiedalloys.Asthequenchingrateincreased,theHRDandexchangecurrentdensityfirstdecreasedandthenincreased.
简介:试验制备了Pd/CeO2-ZSM-5/CC催化剂,测定了其对低中温尾气CO的催化净化活性。试验表明,Pd/CeO2-ZSM-5/CC催化剂具有良好的催化活性,Pd负载量大的催化剂活性越好。CO初始浓度为100ppm,O2浓度为21%,空速为100000h-1时,0.4%Pd催化剂的T100为192℃。
简介:Amethodbasedupontheweightedtotalcrosssection(WTCS)theoryisproposedtocalculatethephoto-ionisationcrosssectionsandtheradiativerecombinationratecoefficientsbetweenthefundamentallevelofCOandthemainelectronicstatesofitscorrespondingion.Totalphoto-ionisationcrosssectionsandradiativerecombinationratecoefficientsaredeterminedfromthecalculationofelementaryvibrationalphoto-ionisationcrosssections.TransitionsbetweenCO~+(X,AandB)andCO(X)areconsidered.Totalphoto-ionisationcrosssectionsandrecombinationcoefficientsarecomputedinthetemperatureinterval500-15000K.
简介:Threetypesofcarbonnano-onions(CNOs)includingNi@CNOs.Fe3C@CNOsandFe0.64Ni0.36@CNOsnanoparticleshavebeensynthesizedbycatalyticdecompositionofmethaneat850℃usingnickel,ironandiron-nickelalloycatalysts.Comparativeandsystematicstudieshavebeencarriedoutonthemorphology,structuralcharacteristicsandgraphiticcrystallinityoftheseCNOsproducts.Furthermore,theelectrochemicalhydrogenstoragepropertiesofthreetypesofCNOshavebeeninvestigated.MeasurementsshowthattheNi@CNOshavethehighestdischargecapacityof387.2mAh/g,coiTespondingtoahydrogenstorageof1.42%.ThiscomparisonstudyshowstheadvantagesofeachcatalystinthegrowthofCNOs.enablingthecontrollablesynthesisandtuningthepropertiesofCNOsbymediatingdifferentmetalsandtheiralloyforusinginthefuelcellsystem.
简介:InthispaperweusedMOF-5andCu3(BTC)2toseparateCO2/CH4andCH4/N2mixturesunderdynamicconditions.Bothmaterialsweresynthesizedandpelletized,thusallowingforameaningfulcharacterizationinviewofprocessscale-up.ThematerialswerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Byperformingbreakthroughexperiments,wefoundthatCu3(BTC)2separatedCO2/CH4slightlybetterthanMOF-5.BecausethecrystalstructureofCu3(BTC)2includesunsaturatedaccessiblemetalsitesformedviadehydration,itpredominantlyinteractedwithCO2moleculesandmoreeasilycapturedthem.Conversely,MOF-5withasuitableporesizeseparatedCH4/N2moreefficientlyinourbreakthroughtest.
简介:ThehotductilityofFe-36NiinvaralloywithdifferentadditionsoftheelementceriumwasinvestigatedusingaGleeble-3800thermal-mechanicalsimulatoroverthetemperaturerange850-1050℃,andtheimprovementmechanismofthehotductilitywasanalyzedusingacombinationofSEM,EDS,andOM.TheresultsindicatedthatFe-36Niinvaralloyexhibitedpoorhotductilitybelow1050℃,whichwasmainlyattributedtoweakgrainboundariesandtheactionofgrainboundarysliding.However,thealloyswithceriumcontentsof0.016%and0.024%bothdemonstratedsubstantialimprovementinthehotductilityovertheentiretestingtemperaturerange.Theobservedimprovementofthehotductilityofthealloywith0.016%ceriumat950℃andthealloywith0.024%ceriumat900℃wasassociatedmainlywiththegrainboundarystrengtheningandtherestrictionofthegrainboundaryslidingbecausetheadditionofceriumreducedthesegregationofsulfuratgrainboundariesandrefinedthegrainstructure.Theoccurrenceandaccelerationofdynamicrecrystallizationwerefoundtoberesponsibleforthehighhotductilityofthealloywith0.016%ceriumat1000℃andthealloywith0.024%ceriumat950-1000℃asaresultoftherefinementofthegrainstructurebyadditionofcerium.
简介:以FeMn合金粉末的形式在铁基合金粉末中添加Mn元素,退火后得到Fe-Cu-Mn部分预合金粉末,采用模壁润滑温压工艺制备Fe-Cu-Mn-C合金,通过对合金密度与硬度的测定以及形貌观察,研究Fe-Cu-Mn-C粉末的压制与烧结行为,以及Mn含量对合金密度和力学性能的影响。结果表明,通过退火处理实现部分预合金扩散而得到的Fe-Cu-Mn粉末具有很好的压制性能,Fe-2Cu-0.5Mn-0.9C压坯密度达到7.37g/cm3,烧结密度为7.33g/cm3;添加适量Mn能有效提升铁基合金的力学性能,其中Fe-2Cu-0.5Mn-0.9C合金的性能最佳,抗拉强度达到715MPa;随Mn含量增加,合金的孔隙增多、密度下降,导致强度和硬度下降。合金的局部氧化对性能产生一定的负面影响。Mn含量对合金组织影响不大,Fe-2Cu-Mn-0.9C合金呈现混合显微组织,由铁素体、珠光体和少量贝氏体构成。Mn的蒸发与凝聚是Fe-Cu-Mn-C的烧结机制。
简介:TheeffectsofheattreatmentsonthephasetransformationbehaviorofTi49Ni49.5Fe1V0.5andTi48Ni48.5Fe1V2.5alloyswereinvestigated.TheresultsindicatethatthealloyssubjectedtodifferentheattreatmentshaveB2structureatroomtemperature.AllthespecimensexhibitatwostageB2→R→B190martensitictransformationoncooling,butaB190→B2one-stagereversemartensitictransformationonheatingexceptagedA1alloy,whichundergoesanabnormaltwo-stagetransformationuponheating.ThephasetransformationtemperaturesareaffectedbyheattreatmentsandVcontent,whichcanbeattributedtothevariationofthesecond-phaseparticlescontentinthematrix.
简介:通过介绍全球及我国近年来CO2的排放状况,首先指出了CO2回收的迫切性及资源化利用的优势,并以CCS(碳捕集与封存)和CCU(碳捕集与利用)为例,分别介绍了诸如地质封存、海洋封存、化学转化和生物转化等规模化回收利用技术,阐述了这些技术的回收原理、工艺路线、安全环保性、技术优势和工业化案例。通过分析CCS各技术的封存能力、封存效果、技术瓶颈及其工业化推广的进度和潜力,指出CCS技术的全球化应用目前还存在一定的风险和制约:通过对比CCU各技术研究重点、转化瓶颈以及工业化进度等,指出化学转化法是目前最有效的CO2规模化回收利用技术:还介绍了其它几种具有规模化潜力的CO2利用新技术。
简介:混合氧化物(Ce0.6Zr0.4O2)由帮助微波的加热一起沉淀准备了的CeO2-ZrO2被用作支持经由早期湿的受精的方法与各种各样的CuO内容(0wt.%15wt.%)准备一系列CuO/Ce0.6Zr0.4O2催化剂。获得的CuO/Ce0.6Zr0.4O2样品被N2吸附,XRD,拉曼,TEM和H2-TPR技术,和他们的催化活动描绘因为公司氧化被调查。结果证明CuO/Ce0.6Zr0.4O2催化剂的活动被CuO的内容强烈影响,并且有10wt.%CuO的催化剂在公司氧化展出了最好的催化活动,它能在催化剂被归因于CuO,和高氧空缺集中的高分散和reducibility。
简介:Globalclimatechangeisoneofthemajorenvironmentalissuesfacedbyhumans.Existingevidenceindicatesthattheanthropogenicpushforariseintheatmosphericconcentrationofgreenhousegases(GHGs)(particularlyCO2)hasbeenaprimarycauseforglobalwarming.Asidefromeconomicandteclinologicalfactors,demographicdynamics(includinghumanconsumptioninabroaddemographicsense)hasbeenamajordriverforCO2emissions.Inthispaper,weperformedbothnonlinearregressionanalysis(basedontheSTIRPATmodel)andgraycorrelationdegreeanalysis(basedongraysystemtheory)ontheimpactofdemographicdynamicsonCO2emissions.OurresultsrevealthatCO2emissionsarepositivelycorrelatedwithpopulationsizeandGDPpercapitaandnegativelycorrelatedwithenergyintensity.WealsoshowthatgraycorrelationdegreewithCO2emissionsforfivevariables(i.e.,householdconsumption,urbanizationrate,householdsize,populationagingrate,populationsize)variessubstantially:householdconsumption>urbanizationrate>householdsize>populationagingrate>populationsize,withhouseholdconsumptionbeingthehighest,andpopulationsizethelowest.TomitigatetheimpactofdemographicdynamicsonCO2emissions,itisofvitalsignificancetonurturepeople’sawarenessofsustainableconsumptionandtoadheretocurrentpopulationcontrolpolicies.