学科分类
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21 个结果
  • 简介:Aseriesofthecoconutactivatedcarbons(CAC)basedabsorbentsmodifiedwithCuandCe(Cu/CAC,Cu/Ce/CAC)werepreparedbyimpregnationtechnologyforcarbondioxidecapture.TheadsocrptionequilibriumsofCO2onCu/CACandCu/Ce/CACweremeasured.TheresultsshowedthattheadsorptioncapacityofCO2ontotheactivatedcarbonmodifiedwithCu/Ceincreasedwiththedecreasingtemperatureinthesamepressure.TheadsorptioncapacityofCO2onCu/CACwashigherthanthatoftheblankCAC,andcomparedwiththeCu/CAC,theadsorptioncapacityofCO2ofCu/Ce/CACwiththemassratioofCu/Ce=30wasimprovedat298and303K.Inaddition,theadsorptionequilibriumdataforCO2atvarioustemperatureswasfittedtoLangmuir,FreundlichandD-Risothermmodels.ItwasfoundthattheD-RequationwasthebestmodelforfittingtheadsorptiondataonCu/Ce/CACatdifferenttemperatures.

  • 标签: ADSORPTION CO2 CAPTURE CU CE rare
  • 简介:ExperimentalresultsonthemagneticfieldbehaviorofthecriticalcurrentinsilversheathedBi-2223tapesarepresented.Theexperimentsconsistoftransportandmagneticmeasurementsinawidetemperaturerangeandinexternalmagneticfieldupto6T.SignificantenhancementoftheintragraincriticalcurrentdensitiesJcareobservedafterirradiationwithfastneutron.Thisisattributedtoanimprovementoffluxpinningcapabilitybytheneutroninduceddefects,buttheweaklinkstructureissomewhatdamagedasevidencedbythesmalldegradationoftransportcriticalcurrentatlowfield.Accordingtothemeasurementofremanentmagneticmomentbeforeandafterirradiationwithfastneutron,theconnectivityinBi-2223tapesisreducedby50%afterirradiatedtoafluenceof2×1021m-2,whichresultedinthecriticalcurrentsdegradatedbyafactorof10%.

  • 标签: NEUTRON IRRADIATION critical current FLUX PINNING
  • 简介:美国宇航局在加州帕萨迪纳的喷气推进实验室研究成功了一种制造YBa2Cu3O7-α高温超导电缆(封装在金属套管内)的新方法。据称,这种方法成本较低,过程易于控制,且对各种前体材料有很强的适应能力。该法分4个步骤:生产具有化学(配)比的前体(Precursor)粉;将前体粉包封在金属套管内;用轧制的方法使前体粉固结;在液态锂金属浴槽内进行处理,使之转变成超导组

  • 标签: 粉末冶金 金属套管 高温超导电缆 锂金属 实验室研究 喷气推进
  • 简介:本文主要进行了二价铜在溶液中用亚硫酸根将其还原成一价铜,并用氯离子作为沉淀剂制取氯化亚铜的研究。氯化亚铜生成过程中会产生H+,反应体系pH对氯化亚铜产品收率影响最大,所以过程中可通过滴加碳酸钠来控制体系酸度,并根据还原反应发生的速度控制碳酸钠的滴加速度来中和体系中的生成的酸,保持体系pH在2.0~3.0,使氯化亚铜产率达到92%以上。

  • 标签: 亚硫酸钠 硫酸铜 氯化亚铜 还原法
  • 简介:1·概述陶瓷刀具是机械切削加工中使用的一种新型切削刀具。它在一些工业发达国家已得到广泛的应用。在我国陶瓷刀具的推广和应用起步于五十年代,但陶瓷刀具推广和应用的进展缓慢,近年来,随着陶瓷刀具在机械切削加工中的不断推广和应用,它的作用逐渐引起了人们的重视,并得到生产实践的证实,已显示出其明显的优越性。陶瓷刀具与硬质合金刀具相比的主要优点是:陶瓷刀片的摩擦系数低,化学稳定性

  • 标签: 复合陶瓷刀具 氧化铝 机械切削 加工质量 合金刀具 表面粗糙度
  • 简介:Fe/Cu/Cemodifiedcoal-basedactivatedcarbon(AC)waspreparedbythesol-gelmethod,andtheeffectofFe/Cu/CeoncatalyticpropertiesofFe/AC,Fe-Cu/ACandFe-Cu-Ce/ACwasinvestigatedinthehydrolysisofcarbonylsulfide(COS)at50°C.Theirsurfacepropertieswereevaluatedbymeansofnitrogenadsorptionandwerecharacterizedbyusingscanningelectronmicroscopy(SEM),X-raydiffracto-metry(XRD)andX-rayphotoelectronspectroscopy(XPS).ThecatalyticactivitiesresultsshowedthatadditionofCuandCe...

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  • 简介:本文用循环伏安测温(CVT)热电化学外推方法首次研究了Cu2S阳极过程动力学性质。实验的塔费尔斜率b值与按迟缓放电机理所导出的Tafel斜率b的理论计算值相符。

  • 标签: CVT Cu_2S Tafel 斜率b
  • 简介:Metalsilver(Ag)wasaddedintoSm0.5Sr0.5CoO3(SSC)bynitratepyrolysismethodtoobtainporouscathodematerial(SSC-Agx)forSOFC.ThecompositephasesinthesematerialsofSSC-AgxwereidentifiedbyX-raydiffraction.ThemicrostructureofanelectrodeonCe0.sSm0.2O1.9intermediatetempera-tureelectrolytebyspraymethod,polarizationcurveandtheimperaturepedancespectraatlowandintermediate(500-800℃)wereinvestigated.Theresultsshowthatthematerialcontaining20%Agexhibitsthebestelectrochemicalproperties,itstotalimpedanceofcathodeisonly1/11ofSSCat600℃,andaquarterofSSCsat750℃.Thecompositetech-niqueofcathodeSm0.5Sr0.5CoO3addedwithAgisanefficientmethodtoimprovethecathodeperformanceofSOFCsoperatingintherangeofintermediatetempera-ture.

  • 标签: 燃料电池 固体氧化物 阴极成分 电化学性质 稀土元素
  • 简介:本文采用多种电化学实验研究方法探讨了酸性氯盐水溶液中Cu(Ⅱ)离子在铜电极上阴极还原的反应机理和电极过程动力学规律。

  • 标签: 酸性氯盐水溶液 Cu(Ⅱ)离子 电化学
  • 简介:Aseriesofcoal-basedactivecarbon(AC)catalystsloadedbyFe-Cu,Fe-Cu-CeandFe-Cu-Lawerepreparedbythesol-gelmethodforcarbondisulfide(CS2)hydrolysisandtheirperformancesforCS2hydrolysisinafixed-bedreactorwereinvestigatedinthiswork.TheresultsshowedthatthekindofrareearthoxideanditscontenthadobviouseffectonhydrolysisremovalofCS2.Theeffectsoftemperature,spacevelocity,CS2concentrationandO2concentrationwerealsodiscussedrespectively.Furthermore,thesuitableoperatingconditionswereobtained.Itwasfoundthatthepoisoningofhydrolysisactivesitescouldresultintheformationofsulfuricacidonthecatalystsurface.

  • 标签: rare earth OXIDE CATALYTIC HYDROLYSIS low
  • 简介:试图为高温度的熔融的盐反应堆的安装和电极的建设开发材料,在750和950湩爠晥湩浥湥?瑳敲杮桴湥湩?猠汯摩猠汯瑵潩?瑳敲杮桴湥湩?眠牯?慨摲湥湩?愠摮瀠敲楣楰慴楴湯猠牴湥瑧敨楮杮的Ni-11Fe-10Cu的高温度的氧化行为上的艾尔和Y的效果

  • 标签: Ni-Fe-Cu 合金 稀土元素 高温度的氧化行为 多层的氧化物规模
  • 简介:Phosphine(PH3)isahighlytoxicairpollutant,commonlyproducedinphosphorouschemicalindustry.Butithasreceivedlessresearchattentionduetoitshandlingdifficultly.COisthemaincontentofthephosphorouschemicalindustrytailgas,theconcentrationofwhichisalwaysmorethan80vol.%,anditcanbethefeedgastoproducevariousvaluableproductssuchasformate,oxalate,andmethanolandsoon.But,PH3isoneoftheimportantbarriers,whichisharmfultothefollowingchemicalprocess.Inordertomakeuseofthetailgas,PH3shouldberemovedfirstly,andCOshouldbecoveredinthewholepurifiedprocedureatthesametime.Inthiswork,themodifiedactivatedcarbon(MAC)wasusedastheadsorbenttoseparatePH3fromthemixturetailgas.SeriesofMACadsorbentswerepreparedfortheadsorptionofPH3,whichloadedCu-FeandCe(La),orseparately.ThePH3adsorptioncapacities,chemicalandphysicalpropertiesofMACwereallinvestigated.Theresultsshowedthatover99%PH3adsorptionefficiencywasachievedwhenusedMACadsorbents.TheremovalefficiencyandPH3adsorptioncapacityoftheCu-Fe-Ce/AC(20:1:0.4)werebothmuchhigherthanthosemodifiedactivatedcarbons.ThemaximumPH3adsorptioncapacitywas71mgofPH3/gofMAContheCu-Fe-Ce/AC,whichweremuchhigherthanliteraturedatausingCuOonlyforadsorbinghydridegases.

  • 标签: PHOSPHINE ADSORPTION ACTIVATED carbon adsorbents rare
  • 简介:15%Ag-addedcubicperovskitesSr0.9La0.1TiO3andRuddlesden-Popper(RP)phasesSr2.7La0.3Ti2O7werefabricatedviahydrothermalsynthesis,coldpressingandhigh-temperaturesintering.Thestructureandthermoelectricpropertieswerealsoinvestigatedforallsamples.TheresultsindicatedthatAgprecipitatedasasecondphase.AgadditionmadeelectricalconductivityandabsoluteSeebeckcoefficientenhanced,asaresult,theZTvalueswereenhancedbothfortwoseries.Comparedwithcubicperovskite,RPphasewassubjectedtosmallerimpactbyAgaddition.ThereasonsforenhancingZTvalueandthedifferentimpactfortwoseriesbyAgadditionwerealsodiscussed.

  • 标签: 热电性能 SEEBECK系数 Ag 钙钛矿相 水热合成法 高温烧结
  • 简介:(Cu60Zr30Ti10)98Y2bulkmetallicglass(Φ4mm×70mm)wasobtainedsuccessfullybycoppermouldcoolingandspraying-casting,andsomesampleswereisothermallyannealedattemperaturesof473and623K,whichwaslowerthantheglasstransitiontemperature(Tg)for1h.Microstructureandpropertiesofas-castandannealedsampleswerestudied.Crystallizationphases(Cu10Zr7andCuZr)wereobservedinannealedsamples,andthespeciesandfractionofthesephasesincreasedwithincreasingannealingtemperature.Mic...

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  • 简介:Selectivecatalyticoxidation(SCO)ofammoniawascarriedoutoverCu-MncompoundscatalystsmodifiedwithtrivalentrareearthoxideCe2O3andLa2O3respectively.TiO2wasusedassupportanddifferentratioofO2weretestedinordertofindanappropriateO2concentration(vol.%),andtheresultsshowedthat1%O2(vol.%)waspropitioustoSCOofammonia.TheeffectsofthetworareearthoxidesmodifiedcatalystsCe2O3-Cu-Mn/TiO2andLa2O3-Cu-Mn/TiO2onthecatalyticactivityandselectivityofammoniaoxidationwereinvestigatedunderthereactionconditionof500ppmammonia,1%O2(vol.%),atthetemperaturefrom125to250oC.TheresultsrevealedthebeneficialroleofCe2O3andLa2O3incatalyticactivityatlowtemperatureandleanoxygenconcentration,whilethemodificationwithCe2O3andLa2O3ledtothenegativeinfluenceonN2selectivity.ForthecatalystsmodifiedwithCeshowedlowerNOandN2OselectivitythanthecatalystsmodifiedwithLa,thentheeffectsofdifferentCeloadingsoncatalyticactivityandselectivitywerealsoconsidered,incombinationwithcatalystspreparationmethods,whichincludeincipientwetimpregnation,sol-gelmethodandco-precipitation.Resultsrevealedthatthecatalystspreparedbysol-gelmethodobtainedpreferablecatalyticactivitycomparedwiththeothers,reaching99%ammoniaat200oC,whereas96%NOwasdetected.Italsoindicatedthatdifferentcatalystpreparationmethodsignificantlydeterminedproductiondistribution.

  • 标签: AMMONIA selective CATALYTIC oxidation (SCO) rare
  • 简介:采用元胞自动机模型建立了05Cr17Ni4Cu4Nb不锈钢固溶过程的二维模型,模拟了固溶过程中的晶粒形核生长以及化合物相的扩散溶解,模拟结果动态地再现了固溶过程的微观组织特征。通过该模型分析了固溶温度和固溶时间对固溶处理后微观组织的影响。

  • 标签: 05Cr17Ni4Cu4Nb 元胞自动机 固溶
  • 简介:MeltspinningtechnologywasusedtopreparetheMg2Ni-type(Mg24Ni10Cu2)100–xNdx(x=0,5,10,15,20)alloysinordertoobtainananocrystallineandamorphousstructure.TheeffectsofNdcontentandspinningrateonthestructuresandelectrochemicalhydrogenstorageperformancesofthealloyswereinvestigated.ThestructurecharacterizationsofX-raydiffraction(XRD),transmissionelectronmicroscopy(TEM)andscanningelectronmicroscopy(SEM)linkedwithenergydispersivespectroscopy(EDS)revealedthattheas-spunNd-freealloydisplayedanentirenanocrystallinestructure,whereastheas-spunNd-addedalloysheldananocrystallineandamorphousstructureandthedegreeofamorphizationvisiblyincreasedwiththerisingofNdcontentandspinningrate,suggestingthattheadditionofNdfacilitatedtheglassformingoftheMg2Ni-typealloy.TheelectrochemicalmeasurementsindicatedthattheadditionofNdandmeltspinningimprovedtheelectrochemicalhydrogenstorageperformancesofthealloyssignificantly.Thedischargecapacitiesoftheas-castandspunalloysexhibitedmaximumvalueswhenNdcontentwasx=10,whichwere86.4,200.5,266.3,402.5and452.8mAh/gcorrespondingtothespinningrateof0(As-castwasdefinedasthespinningrateof0m/s),10,20,30and40m/s,respectively.Thecyclestability(S20,thecapacitymaintainrateat20thcycle)oftheas-castalloyalwaysrosewiththeincreasingofNdcontent,andthoseoftheas-spunalloysexhibitedthemaximumvaluesforNdcontentx=10,whichwere77.9%,83.4%89.2%and89.7%,correspondingtothespinningrateof10,20,30and40m/s,respectively.

  • 标签: 电化学测试 铸态合金 储氢性能 纳米晶体 NDX 非晶化