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1.
1IntroductionLuisaclassicCLreagentusedmostlyinanalyticalchemistry.TheCLreactionsofLuwithhydrogenperoxidecatalyzedbymetalions[1,2]andorganicreductantssuchasglucose,anduricacid[3,4]havebeenstudiedsomuch,butthereactionsofLuwithraremetalreductantshaveneverbeenr…  相似文献   

2.
1.IntroductionAsanewkindofrareearthmolybdenumcathodematerial,MoY2O3isexpectedtosubstituteradioactiveWThO2cathodematerialsinthefuture.Mo4wt%Y2O3allows,relativetoMoLa2O3〔12〕(whichhasbeenwidelystudiedsince1970sinordertosubstituteWThO2cathodemater…  相似文献   

3.
0 IntroductionAg basedfillermetalisthemostimportantandwidelyusedbrazingmaterialandtheeffectoftracecontentofimpuritiesintroducedbytheproductionprocessandrawmaterialsonthepropertieshasbeendeeplystudied[1~ 7] .FortheimpuritiesPbandBiinAg basedfillermetal,the…  相似文献   

4.
1IntroductionSpectrophotometricdeterminationofgold(Ⅲ)hasbeenstudied[1]andappliedextensively,butofgold(Ⅰ),fewpaperswererepor...  相似文献   

5.
1 IntroductionMoltencarbonatefuelcell (MCFC)isbelievedtobeoneofthemostpromisingnewenergyconversiondevicethatconvertschemicalenergyinfossilfuelsintoelectric ity[1~ 5].Itisahighlyefficientandenvi ronmentallycleansourceofpowergenera tion .Manyorganizationsworld…  相似文献   

6.
1 INTRODUCTIONMetalInjectionMolding (MIM )developedveryfastasakindofpowdermetallurgynet shapingpro cessinrecentyears .Introducingtheideaofplasticinjectionmolding ,thebinderisaddedintometalpowdersasthevehicleofflowabilitytogetmoldedparts .Thebinderhastobere…  相似文献   

7.
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   

8.
Electrodeposition of dixanthogen on surface of pyrrhotite electrode   总被引:2,自引:1,他引:1  
1 INTRODUCTIONInthepastdecades ,greatadvancestowardsun derstandingthereactionsofsulfidemineralsurfacewithxanthatereagentshavebeenmade .Thekeytotheseadvancesisrecognizingthatthereactionsin volvechargetransfer .Manydynamicelectrochemicaltechniqueshavebeena…  相似文献   

9.
1 INTRODUCTIONCu basedshapememoryalloys (SMAs)arecom merciallyattractivesystemsforapplicationsbecauseoftheirlowercost.Uptonow ,Cu ZnandCu AlbasedSMAshavebeenwidelystudied .However,theseCu basedalloys,especiallythealloysofCu Al NisystemandtheoneswithhighAlcont…  相似文献   

10.
1 IntroductionFluorometricmethodshavebeenproventobeusefulfortheassayofmetalionsinsolution[1 ,2 ] .Recently ,thefluo rescencedeterminationofrareearthele mentshasbeenreportedinagreatdealofpapers .Mostoftheanalyticalmethodsin volvedcomplexationofrareearthelement…  相似文献   

11.
Ignition time of self-propagating high-temperature synthesis by laser   总被引:1,自引:0,他引:1  
1 INTRODUCTIONSHS ,theself propagatinghigh temperaturesyn thesis,wasfirstdiscoveredbyMerzhanovandBorovinskayawhentheystudiedsolidfu  相似文献   

12.
1 INTRODUCTIONThroughoutthecastingoperation ,moldfillingplaysaveryimportantroleincastingqualitycontrol.Manyofthecastingdefectscanberelatedtothefluidflowphenomenainvolvedinthisstageoftheopera tion .Ithasbeennotedthatthepropergatingdesigniscrucialtoachiev…  相似文献   

13.
1IntroductionMoreandmorecarbonatemeltshavebeenemployedtoserveaselectrolyterecently,especiallyinmoltencarbonatefuelcells(MCFC).MCFCisbelievedtobeoneofthemostpromisingnewenergyconversiondevicethatconvertschemicalenergyinfossilfuelsintoelectricity[1~3].MCFCt…  相似文献   

14.
1 INTRODUCTIONThereliabilityofsolderjointsisoneofthecriti calissuesinSurfaceMountTechnology (SMT )field[1~ 3 ] .Themoresevereserviceenvironmentalconditionsofelectronicdevicesinautomotiveapplica tion ,andthedevelopmentofadvancedinterconnec tiontechnologiesfora…  相似文献   

15.
Tensile and creep properties of Mg-9Al based alloys containing bismuth   总被引:6,自引:0,他引:6  
1 INTRODUCTIONMagnesiumalloysarebeingincreasinglyusedinautomobileindustryinordertodecreasemasstherebyreducingfuelconsumptionandpollution[1~ 4 ] .How ever,thereductionofyieldstrengthandcreepresis tanceofMg Alalloyabove 12 0℃limitstheirapplica tionsinautomobile…  相似文献   

16.
1 IntroductionAsakindofseparationtechnique ,solventextractioniswidelyapplied .More over ,insynergisticsystemtheextracingpowerofthemixtureexceedsobviouslythesumeffectoftheextractingpowersofitscomponents .Theenhancedextractionhasbeenobservedinmanymetalextra…  相似文献   

17.
1 INTRODUCTIONRecentlyaluminum raremetalalloysattractmuchinterest.Metallicthermoreduction ,inwhichoxidesandchloridesofraremetalarereducedandin situalloyedbyaluminum ,hasthebestprospectinallproductionmethodsofaluminum raremetalalloys .Howeverthismethodismo…  相似文献   

18.
1 INTRODUCTIONMagnesiumalloyshavemanyadvantagessuchaslowdensity ,highspecificstrength ,goodelectromag neticshieldingcharacteristics ,excellentcastabilityandmachinabilityetc .Magnesiumisanabundantele mentsinceabout 1.93% (massfraction)ofearthcrustconsistofmagne…  相似文献   

19.
1 INTRODUCTIONMolybdenumandtungstenshowverysimilarchemi calpropertiesowingto :1)theyarealllocatedattheⅥBcolumnintheperiodictableofelementsand 2 )the“lan thanidecontraction”makestheradiiofMo6+ andW6+(Zr4 + andHf4 + ,Nb5+ andTa5+ )almostequaltoeachother .Thisbringsabou…  相似文献   

20.
TheTransactionsofNonferrousMetalsSocietyofChina(hereafterTrans .NonferrousMet.Soc .China) ,foundedin 1991andsponsoredbyTheNonferrousMetalsSocietyofChina ,ispublishedbimonthlyandmainlycontainsreportsoforiginalresearchwhichreflectthenewprogressesinthefieldofno…  相似文献   

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