简介:AseriesofnovelAgCl/Ag2CO3heterostructuredphotocatalystswithdifferentAgClcontents(5wt%,10wt%,20wt%,and30wt%)werepreparedbyfacilecoprecipitationmethodatroomtemperature.TheresultingproductswerecharacterizedbypowderX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),X-rayphotoelectronspectroscopy(XPS),andultraviolet–visiblediffusereflectancespectroscopy(UV–VisDRS),respectively.Thephotocatalyticactivityofthesampleswasevaluatedbyphotocatalyticdegradationofmethylorange(MO)underUVlightirradiation.WiththeoptimalAgClcontentof20wt%,theAgCl/Ag2CO3compositeexhibitsthegreatestenhancementinphotocatalyticdegradationefficiency.Itsfirst-orderreactionrateconstant(0.67h-1)is5.2timesfasterthanthatofAg2CO3(0.13h-1),and16.8timesfasterthanthatofAgCl(0.04h-1).TheformationofAgCl/Ag2CO3heterostructurecouldeffectivelysuppresstherecombinationofthephoto-generatedelectronandhole,resultinginanincreaseinphotocatalyticactivity.
简介:在氩气气氛下,将Ag2O与石墨通过机械活化或热还原反应生成Ag,对其等温还原过程的动力学进行研究。结果表明,采用Johnson-Mehl-Avrami模型能合理地解释Ag2O与石墨经机械活化和热还原合成Ag的过程。采用相同的模型来研究机械活化和热还原反应合成Ag的动力学时,机械活化还原过程中的Avrami指数比热还原的要高;热还原和机械活化过程中的晶核长大机制分别是扩散控制和界面控制。
简介:ToreducetheproductioncostofBi-2223superconductingtapes,Bi-2223/Ag/Nitapeswerefabricatedbythepowder-in-tubeprocess.TheeffectofheattreatmentonthemicrostructureandcriticalcurrentoftheBi-2223/Ag/Nitapeswerestudied.ThephasecompositionsofthesampleswerecharacterizedusingXRD.ThemicrostructurewasobservedusingSEM.ExperimentalresultsindicatethathighertemperatureismoreconducivetotheformationofBi-2223phaseatanatmosphereof8.5%O2.Afterthetwo-steph...
简介:在之中无铅焊接材料,Sn-Ag-Cu合金有许多优点优异界面的性质和高度例如好弄湿的性质,爬抵抗。在这篇文章,组织和Sn-Ag-Cu材料的焊接性能被调查。二合金的表面形态学被实体镜的显微镜观察并且扫描电子显微镜(SEM)。化学宪法被X光检查精力散的光谱学(版本)检验。Sn-Ag-Cu的机械性质焊接Sn-Cu与那些相比系统地被评估焊接。结果证明Sn-Ag-Cu焊接基于不同焊接垫不同焊接性质。在接口的金属间化合的化合物(IMC)的厚度与老化时间增加。为镀金的垫,有很多IMC图,并且在焊接连接它能减少电的连接的可靠性。Sn-Ag-Cu焊接关节表演在传统的Sn-Cu上的一个优异机械性质焊接。酒窝减少和洞的数字增加因为Sn-Cu0.7合金和Sn-Ag3.0-Cu0.5合金的破裂表面有同类地分布式的许多小尺寸酒窝。
简介:MoleculardynamicssimulationwascarriedouttoinvestigatetheliquidandamorphousmicrostructuresofbinaryAgx-Rh(100-x)(x=25,50,75inatomfraction)alloys.SegregationfeatureofhomogeneousinteratomicbindingofAg-Rhliquidwasfoundandprobed,whichcanberetainedintoamorphoussolidsuponrapidcooling.Homogeneousbindingmayoccurwhenthedifferenceintheelementalatomicsizesislessthan10%.Theicosahedrainliquidbeforetheformationofamorphousstateexistinastablestateandthenetworkformedby1551-clustersinmoltenalloyswouldinhibitthecrystallizationanddiffusionofatoms.Ahigherdegreeof1551-clusterswillbefavorabletoformmetallicglasses.
简介:Theobjectiveofthisresearchistopreparespeciallydesignedsurfacetextureonhardsteelsurfacebyelectrochemicalmicromachining(EM)andtoincorporateelectrolessplatedAg/MoS2solidlubricantcoatingintothedimplesofEMtexturedsteelsurfacetoeffectivelyreducefrictionandwearofsteel-steelcontacts.ThefrictionandwearbehavioroftheAg/MoS2solidlubricantcoatingonEMtexturedsteelsurfacewasevaluatedinrelationtothesizeandspacingofthedimplesthereon.Themicrostructur...
简介:对于有机卤代物的电化学还原,银基纳米催化剂显示出优异的催化活性。采用简单的化学还原法制备Ag-Ni纳米颗粒(NPs),并采用X射线衍射、紫外-可见光谱、透射电镜以及能量散射谱等方法对制备的纳米催化剂进行表征。采用循环伏安法、计时电流法以及电化学阻抗谱在有机介质中研究Ag-Ni纳米颗粒对苄氯还原的电催化活性。结果表明:Ni元素的加入可明显减小Ag-Ni纳米颗粒的尺寸,使苄氯的还原峰电位φp正移且增加Ag-Ni纳米颗粒的催化活性。然而,当Ni的含量大于一定值后,Ag-Ni纳米颗粒的催化活性反而降低。同时,对Ag-Ni纳米颗粒的协同催化效应进行探讨。
简介:Basedonthephasediagrams,measuredactivitiesandtheannexationprinciple,thecalculatingmodelsofmassactionconcentrationsforIn-Pb-AgandIn-Bi-Sbternarymetallicmeltshavebeenformulated.Theresultsofcalculationbothagreewithpractice,andobeythelawofmassaction,showingthatthemodelsformulatedcanreflectthestructuralrealityofthecorrespondingmeltsandtheannexationprincipleisapplicabletothethem.
简介:由到Mg-Cu-Ag-Gd合金的Nb的次要的增加,Mg-Cu-Ag-Gd-Nb体积有象好机械性质一样的改进热稳定性和腐蚀抵抗的金属性的玻璃(BMG)被开发。Mg54Cu26.5Ag8.5Gd11xNbx(x?=?0,1)有2的一条直径的BMG?公里被扔的铜模子制作。Mg54Cu26.5Ag8.5Gd10Nb1BMG展览扩大了58的supercooled液体区域?K。电气化学的大小显示Nb的增加在增加的腐蚀潜力证实的NaCl答案改进基于Mg的BMG的腐蚀抵抗,尽管在NaOH答案的BMG的腐蚀行为上的Nb的重要效果都没被观察。Mg-Cu-Ag-Gd-NbBMG也显示出高压缩的力量直到890?MPa和大约1.9%的有弹性的紧张。
简介:TheprocesstoobtainhighT(110K)phasequickly,themicrostructureandpropertiesofAg-sheathedBi(Pb)-Sr-Ca-Cu-Osuperconductortapeshavebeenstudied.ItwasfoundthattheformationtimeofthehighTcphasewasgreatlyshortenedbytheadditionofmoreCaandCutothenominalcompositionofBi(Pb):Sr:Ca:Cu=2:2:2:3andtheadoptionofappropriatesinteringtemperatureandcoolingrate.SuperconductorpowderwithpredominanthighT,phasewaspreparedaftera840C/50htreatment.TheJoftheAg-sheathedtapesandthemagneticfielddependenceofJwereobviouslyimprovedbyrepeatedlypres-singandsintering.Themaximumtransportcurrentdensityat77Kinazeromagneticfieldwas12,200A/cm2.ThemagneticdependenceofJwassummarizedasfollows:6.450A/cm2(B⊥1.B∥S.0.1T)1,810A/cm2(B⊥1.B∥S,1T),390A/cm2(B⊥1.B∥S,2T)(B:magneticfield.1:electriccurrent.S:surfaceoftapes).TheimprovementofJwasattributedtotheformationoftheplate-likestructurewithhomogeneouscompositiondistributionandthestrongc-axistexture.
简介:EffectofaddedCo2+(aq)oncopperelectrowinningwasstudiedusingdopedpolyaniline(Pani)andPb-Ag(1%)anodesandastainlesssteelcathode.ThepresenceofaddedCo2+(aq)intheelectrolytesolutionwasfoundtodecreasetheanodepotentials.TheoptimumlevelofCo2+(aq)concentrationintheelectrolyte,withrespecttothemaximumsavingofpowerconsumptionwasestablished.Linearsweepvoltammetry(LSV)wasusedtostudytheinfluenceofaddedCo2+(aq)ontheanodicprocessesinacoppersulfate-sulfuricacidelectrolyte.Theoxygen-evolutionpotentialforPanianodeisdepolarisedatlowercurrentdensities(≤0.01A/cm2)andattainssaturationatρ(Co2+)o≈0.789g/L;whilsttheoxygen-evolutionpotentialforPb-Ag(1%)anodeisdepolarisedathighercurrentdensities(≤0.02A/cm2)andattainssaturationatρ(Co2+)o≈1.315g/L.Thepreferredorientationsofthecopperdepositschangefrom(220)to(111)withtheadditionof0.394?0.789g/LCo2+buthigherconcentrationsfavor(220)orientationagain.
简介:Auniformtransienttemperaturefieldmodelofelectricalcontactsoperationwasfoundbyanalyzingtheprocessofclosingarc→constrictionresistanceJouleheat→breakingarc.EssentialparametersofAg/La2NiO4electricalcontactmaterialfortransienttemperaturefieldcalculationwereobtainedthroughtestsofelectricalcontactexperimentalinstrumentunder18VDCindifferentcurrents,othercorrelationexperiments,andcalculationanalysis.Thefiniteelementmethodwasappliedtosolvethetransienttemperaturefield,andthefeaturesanddistributionofthetransienttemperaturefieldwereobtained.Theconditionofmaterialerosionandmasstransfercanbeforecastedbythosecalculationresults.ItisbeneficialtoresearchaboutthelifetimeofAg/La2NiO4electricalmaterial.
简介:TheagingbehaviorofAl-Cu-Mg-AgalloyswithhighCu/Mgwasstudiedbytransmissionelectronmicroscopy(TEM)andsmall-angleX-rayscattering(SAXS)usingsynchrotronradiation.TEMstudyrevealsthatthemajorstrengtheningphasesofthealloyafteragingat160?Cfor10hareΩandlessθ′.SAXSstudyshowsthatthescatteringpatternsarecomposedofseveralconcentriccirclesatthebeginningofagingprocess,whichisreplacedbythebutterfly-wingsscatteringpatternswiththeincreaseofagingtime...
简介:基于化学镀Ni工艺,研究Sn-3.5Ag-0.5Cu合金在Ni-P(-SiC)镀层/SiCp/Al基体上的润湿行为,分析镀层的显微结构和Sn-3.5Ag-0.5Cu/Ni-P(-SiC)镀层/SiCp/Al体系的润湿和界面行为。结果表明,SiC颗粒均匀地分布在镀层中,且Ni-P(-SiC)镀层与SiCp/Al复合材料之间没有界面反应。Sn-3.5Ag-0.5Cu对Ni-P、Ni-P-3SiC、Ni-P-6SiC和Ni-P-9SiC镀层/SiCp/Al基体对应的最终接触角分别为~19°、29°、43°和113°。在Sn-3.5Ag-0.5Cu/Ni-P-(0,3,6)SiC镀层/SiCp/Al界面处形成含有Cu、Ni、Sn和P的反应层,其主要包含Cu-Ni-Sn和Ni-Sn-P相。此外,熔融的Sn-Ag-Cu合金可以通过Ni-P/SiC界面渗入Ni-P(-SiC)复合镀层与SiCp/Al基体接触。