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1IntroductionLuisaclassicCLreagentusedmostlyinanalyticalchemistry.TheCLreactionsofLuwithhydrogenperoxidecatalyzedbymetalions[1,2]andorganicreductantssuchasglucose,anduricacid[3,4]havebeenstudiedsomuch,butthereactionsofLuwithraremetalreductantshaveneverbeenr… 相似文献
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J.S.Wang ) M.L.Zhou) J.X.Zhang) Z.R.Nie) T.Y.Zuo) G.J.Zhang) ) State Key Laboratory of Materials Chemistry Applications Peking University Beijing China) Schoolof Materials Science Engineering Beijing Polytechnic Univers 《金属学报(英文版)》1999,12(4):602-606
1.IntroductionAsanewkindofrareearthmolybdenumcathodematerial,MoY2O3isexpectedtosubstituteradioactiveWThO2cathodematerialsinthefuture.Mo4wt%Y2O3allows,relativetoMoLa2O3〔12〕(whichhasbeenwidelystudiedsince1970sinordertosubstituteWThO2cathodemater… 相似文献
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0 IntroductionAg basedfillermetalisthemostimportantandwidelyusedbrazingmaterialandtheeffectoftracecontentofimpuritiesintroducedbytheproductionprocessandrawmaterialsonthepropertieshasbeendeeplystudied[1~ 7] .FortheimpuritiesPbandBiinAg basedfillermetal,the… 相似文献
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1IntroductionSpectrophotometricdeterminationofgold(Ⅲ)hasbeenstudied[1]andappliedextensively,butofgold(Ⅰ),fewpaperswererepor... 相似文献
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1 IntroductionMoltencarbonatefuelcell (MCFC)isbelievedtobeoneofthemostpromisingnewenergyconversiondevicethatconvertschemicalenergyinfossilfuelsintoelectric ity[1~ 5].Itisahighlyefficientandenvi ronmentallycleansourceofpowergenera tion .Manyorganizationsworld… 相似文献
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1 INTRODUCTIONMetalInjectionMolding (MIM )developedveryfastasakindofpowdermetallurgynet shapingpro cessinrecentyears .Introducingtheideaofplasticinjectionmolding ,thebinderisaddedintometalpowdersasthevehicleofflowabilitytogetmoldedparts .Thebinderhastobere… 相似文献
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Preparation of Phosphors MAl_2O_4∶Eu~(2 )(M=Ca,Sr,Ba) by Microwave Heating Technique and Their Phosphorescence 总被引:3,自引:0,他引:3
1 IntroductionMAl2 O4∶Eu2 (M =Ca ,Sr ,Ba )havebeenknownasexcellentphosphorswithemissioncolorsfrombluetogreenun derultravioletandcathode rayexcita tion[1~ 3].Studiesonphosphorsweremostlyperformedin 1 960s′andearly 1 970s′mainlyforlampandcathode raytubeap plication .In 1 990… 相似文献
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1 INTRODUCTIONInthepastdecades ,greatadvancestowardsun derstandingthereactionsofsulfidemineralsurfacewithxanthatereagentshavebeenmade .Thekeytotheseadvancesisrecognizingthatthereactionsin volvechargetransfer .Manydynamicelectrochemicaltechniqueshavebeena… 相似文献
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1 INTRODUCTIONCu basedshapememoryalloys (SMAs)arecom merciallyattractivesystemsforapplicationsbecauseoftheirlowercost.Uptonow ,Cu ZnandCu AlbasedSMAshavebeenwidelystudied .However,theseCu basedalloys,especiallythealloysofCu Al NisystemandtheoneswithhighAlcont… 相似文献
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1 IntroductionFluorometricmethodshavebeenproventobeusefulfortheassayofmetalionsinsolution[1 ,2 ] .Recently ,thefluo rescencedeterminationofrareearthele mentshasbeenreportedinagreatdealofpapers .Mostoftheanalyticalmethodsin volvedcomplexationofrareearthelement… 相似文献
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1 INTRODUCTIONSHS ,theself propagatinghigh temperaturesyn thesis,wasfirstdiscoveredbyMerzhanovandBorovinskayawhentheystudiedsolidfu 相似文献
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1 INTRODUCTIONThroughoutthecastingoperation ,moldfillingplaysaveryimportantroleincastingqualitycontrol.Manyofthecastingdefectscanberelatedtothefluidflowphenomenainvolvedinthisstageoftheopera tion .Ithasbeennotedthatthepropergatingdesigniscrucialtoachiev… 相似文献
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1IntroductionMoreandmorecarbonatemeltshavebeenemployedtoserveaselectrolyterecently,especiallyinmoltencarbonatefuelcells(MCFC).MCFCisbelievedtobeoneofthemostpromisingnewenergyconversiondevicethatconvertschemicalenergyinfossilfuelsintoelectricity[1~3].MCFCt… 相似文献
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1 INTRODUCTIONThereliabilityofsolderjointsisoneofthecriti calissuesinSurfaceMountTechnology (SMT )field[1~ 3 ] .Themoresevereserviceenvironmentalconditionsofelectronicdevicesinautomotiveapplica tion ,andthedevelopmentofadvancedinterconnec tiontechnologiesfora… 相似文献
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1 INTRODUCTIONMagnesiumalloysarebeingincreasinglyusedinautomobileindustryinordertodecreasemasstherebyreducingfuelconsumptionandpollution[1~ 4 ] .How ever,thereductionofyieldstrengthandcreepresis tanceofMg Alalloyabove 12 0℃limitstheirapplica tionsinautomobile… 相似文献
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1 IntroductionAsakindofseparationtechnique ,solventextractioniswidelyapplied .More over ,insynergisticsystemtheextracingpowerofthemixtureexceedsobviouslythesumeffectoftheextractingpowersofitscomponents .Theenhancedextractionhasbeenobservedinmanymetalextra… 相似文献
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1 INTRODUCTIONRecentlyaluminum raremetalalloysattractmuchinterest.Metallicthermoreduction ,inwhichoxidesandchloridesofraremetalarereducedandin situalloyedbyaluminum ,hasthebestprospectinallproductionmethodsofaluminum raremetalalloys .Howeverthismethodismo… 相似文献
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Microstructure and properties of AZ80 magnesium alloy prepared by hot extrusion from recycled machined chips 总被引:5,自引:0,他引:5
1 INTRODUCTIONMagnesiumalloyshavemanyadvantagessuchaslowdensity ,highspecificstrength ,goodelectromag neticshieldingcharacteristics ,excellentcastabilityandmachinabilityetc .Magnesiumisanabundantele mentsinceabout 1.93% (massfraction)ofearthcrustconsistofmagne… 相似文献
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Developing new reagent for selectively precipitation of molybdenum from tungstate solution 总被引:2,自引:0,他引:2
1 INTRODUCTIONMolybdenumandtungstenshowverysimilarchemi calpropertiesowingto :1)theyarealllocatedattheⅥBcolumnintheperiodictableofelementsand 2 )the“lan thanidecontraction”makestheradiiofMo6+ andW6+(Zr4 + andHf4 + ,Nb5+ andTa5+ )almostequaltoeachother .Thisbringsabou… 相似文献
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《中国有色金属学会会刊》2001,(3)
TheTransactionsofNonferrousMetalsSocietyofChina(hereafterTrans .NonferrousMet.Soc .China) ,foundedin 1991andsponsoredbyTheNonferrousMetalsSocietyofChina ,ispublishedbimonthlyandmainlycontainsreportsoforiginalresearchwhichreflectthenewprogressesinthefieldofno… 相似文献