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1.
Catalytic Oxidative Properties and Characterization of CuO/CeO2 Catalysts   总被引:1,自引:0,他引:1  
CeO2 ormaterialscontainingCeO2 possessuniqueredoxpropertiesincatalyticprocesses[1~ 3] ,andcanimprovedispersionofactivecomponentsonthesup portsandthusenhancetheirthermalstabilityandcatalyticactivity .MoststudieshaveusedCeO2 asanadditive[4 ] andexamineditsintera…  相似文献   

2.
Perovskite typeoxides (generalformulaABO3 )havebeenattractingmuchattentionformorethantwodecadesduetotheirpotentialcommercialapplicationsascatalystsforvariousreactions :oxidationofCO[1~ 3 ] andlighthy drocarbons[4~ 7] ,combustionofnaturalgasorCH4 [8~ 1 1 ] (tocontrolN…  相似文献   

3.
Adsorption of Er( Ⅲ ) and Its Mechanism on Diglycolamidic Acid Resin   总被引:15,自引:0,他引:15  
Thesynthesischaracterizationandadsorp tionpropertyofpolymericmaterialshavebeenpublishedinrecentyears[1~ 9] .DiglycolamidicacidresinDAARisanovelpolymericmaterialwhichcontainsafunctionalgroup [-N(CH2 COOH ) 2 ].Itpossessesnotonlyprotonthatcanexchangewithcation ,b…  相似文献   

4.
Crystalengineeringofcoordinationpoly merswithopenframeworksassembledfromor ganic metalcompoundshasbeenofgreatinter estsowingtotheirpotentialpropertiesasnovelmaterialssuchasgasadsorption[1,2 ] ,ion ex change[3] andcatalysis[4] .Theconstructionofcoordinationpolym…  相似文献   

5.
YBa2 Cu3O7,so called 12 3compound ,isanim portanthighTc oxidesuperconductor[1] .Itscrystalstructureisquasiperovskite (Fig .1)witharegularstackingofBaandYlayersinthec direction .Itisorthorhombic ,belongingtothePmmmspacegroupwithoneformulaunitperprimitivecell .Theyttr…  相似文献   

6.
Ithasbeenmorethan 2 0yearssincerareearths (RE)areappliedinagriculture .Duringlastyears ,theaccumulationofREinsoilswasacceleratedbecauseRE NH4HCO3 complexfertilizerswereextensivelyappliedanddirectlyusedinsoils[1] ,sothereisagrowingconcernabouttheadverseeffectof…  相似文献   

7.
Basedonthehepaticcontentsoflipidper oxidesafter 0 0 5mg·kg-1bodyweight(bw)ofSmCl3andPrCl3weregivenbyp .o ,i .pandi.vinjectiontotheratsdailyfor 1 2d ,Nieetal[1] foundthattheybothinhibitedthelipidperoxidationandelevatedtheSODactivity .However,ahigherdose (2 8mmol·kg-1)ofL…  相似文献   

8.
ItisnowwellestablishedthatnumerousfactorsinfluencethereactionpathwaysinsuchacomplicatedY Ba Cu Osystem ,forin stance ,thecrystallinesizesandthereagent[1] ,thedegreeofmixingandhomo geneity[2 ,3] ,theoxygenpartialpressure[4~ 6 ] ,aswellasthereactorsizeandcrucibleshap…  相似文献   

9.
Thepoormechanicalpropertiesofcastmaterials ,especiallylowtoughness ,isamainfactorlimitingtheapplicationofprecisecastdies[1] .ThroughthemodificationofcastH1 3steelbyRE ,thedendritesegregationofCH1 3steelwasimprovedandgrainboundarycarbidewasalsoundercontrol.Acc…  相似文献   

10.
Becauseoftheirpossiblerelevancetomodelcompoundsofcationtransportacrossmembranes,differenttypesofopenchain“crown”ethermoleculeshavebeensynthesizedinordertostudytheirinteractionwithsodium ,potassiumandrareearthions[1,2 ] .Panetal.[3 ] showedthatCe3 formsa 1∶1com…  相似文献   

11.
IntermetallicLnNi5 compoundswithCaCu5 structuraltypeinthetransitionmetalsublatticesubstitutedbyMn ,Al ,Co ,Sn ,GearepromisingmaterialsforM -Hbatteries[1] .Usuallythesecompositionshavebeenpreparedbymeltingofthepureelementsfollowedbyap propriateannealingandthenb…  相似文献   

12.
Mostoforganolanthocenecomplexescon tainingLn Cσ bondhaveproventobehighlyefficientcatalystsorprecatalysts ,suchasforC-Hbondactivationreaction[1] ,hydrogenationreaction[2 ] ,andhomogenouspolymeriza tion[3] .However ,amongthisfamilyofcom plexes ,σ bondedorganolanthoc…  相似文献   

13.
Spectrophotometricmethodsarewidelyusedforthedeterminationofrareearthele ments,andmono and 2 ,7 bisazo derivativesofchromotropicacidarebeingextensivelyem ployed[1~ 2 ] .Thoughmorethanahundredreagentsbasedonasymmetricalphosphonebi aszoderivativesofchromotropicac…  相似文献   

14.
Themagneticpropertiesofheteropolynu clearcomplexescontainingboth 4fand 3dionshaveattractedconsiderableinterestssince1 985 [1] .Carboxylicacidisakindofpotentialligandforthedesignandsynthesisofthiskindofmagneticmolecularmaterials .Somecar boxylatecompoundswerep…  相似文献   

15.
Anumberoflanthanideternarycomplexescon tainingheterocyclicamineshavebeenreportedsince1960 [1] .Inrecentyearsmuchattentionhasbeenpaidtoquaternarycomplexesoflanthanidesbecauseofin terestingstructure ,coordinationmode ,competitionre actionandproperty[2~ 9] .ESRcane…  相似文献   

16.
2 mercaptobenzothiazolewasfirstreportedbyHofmann[1 ] in 1 887.Ithasbeenusedasanacceleratorinthevulcanizationofrubberformanyyears .Todayitisstillbeingusedasamainacidicacceleratorinrubberindustry .Butithasdisadvantagesofvulcanizationreversionandeasyscorch[2 ] whe…  相似文献   

17.
Therearealotsofreportsaboutthepoly merizationofacrylonitrile (AN) [1~ 3] .Intheradicalpolymerization ,usuallyitisinitiatedbybenzoperoxide ,K2 S2 O4 Na2 S2 O3,Fe2 + H2 O2 andsomeorganiccompounds .There portsonorganolanthanidesassingle componentcatalystswasrarelyinlitera…  相似文献   

18.
Teapolysacchridecomplex ,oneofthebasicmacromoleculesintea ,hasmanyphar maceuticaleffectsandiseasytodissolveinteainfusion[1] .Zhongetal .[2 ] discoveredthatthereisaREbindingpolysaccharideinleavesofteaplant (CamelliaSinensisLO .Kuntze) .Inthispaper ,thestudyontheco…  相似文献   

19.
Thepervoskite typeLaCrO3materialhasbeenextensivelyinvestigatedforitsapplica tion ,suchasanelectrodematerial,electro catalysisandgassensor[1~ 3] .Chemicalcom positionandphasepurityaretwoparameterswhichoftenaredifficulttobecontrolledinmulticomponentmetaloxide…  相似文献   

20.
Stainlesssteelsare practicallyusedinneutralmedialwhichdon’tinitiatestresscorrosioncracking(SCC)aslongasthesteelsareprotectedfromlocal izedcorrosion[1] .Theoriginal 30 4steelcanavoidpittingbutcrevicecorrosion .Ifcrevicecorrosionisavoidedbyadditionalalloyingto…  相似文献   

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