简介:Heterogeneousprecipitationmethodwasusedtopreparedsurfacecoatingonself-madeBaMgAl10O17:Euphosphor.Resultsillustratethatthecoatingfilmcanbesilicondioxideinamorphousstatewith50nminthickness.Photoluminescenceresultsindicatethatthecoatinglayerpresentsanobservableimprovedeffectontheenhancementofthermalstability.Whenbakedat600℃for1h,theluminanceofcoatedBAMkeepsat92%higherthanthatofuncoatedBAMby23%.ThisprotectiveeffectcanbeattributedtothehighcompactdegreeanduniformityofthisamorphousSiO2coatingfilmwhichisservedasadiffusionblocklayertoinbreakoxygenatom,thusreleasestheoxidationextentofEu2+effectively.
简介:Inthispaper,varioustechniquesincludingBET,XRD,SEMandXPSwereusedtostudythesinteringofpureandLa2O3-dopedtitania.Theexperimentalresultsshowthatsinteringoftitaniaproceedsviavolumediffu-sion.Addingoflanthanumoxidedecreasestherateofsinteringandhindersthephasetransitionfromanatasetorutilecrystalbystrongsurfaceinteractionbetweenthemixedcrystals(La4Ti9O24,La0.66TiO2.99)andTiO2.
简介:Ternarycomplexesofeuropiumandterbiumwithbenzoicacidand1,10-phenanthroline[RE(BA)3phen](BA=benzoatephen=1,10-phenanthroline)wereintroducedintoasilicamatrixbysol-gelmethod.Thethermalstabilityandluminescencebehaviorofthecomplexesinsilicagelswerestudiedincomparisonwiththecorrespondingsolid-statecomplexesbythermaldecomposition,excitationandemissionspectra.Thethermalstabilityofthecomplexesisenhancedinsilicagelmatrixandtheluminescenceremainesunchanged.
简介:Theeffectofanexternalelectricfieldonthecrystallizationbehaviorofamorphous(Nd0.1Fe0.9)3Balloywasinvestigated.ThecrystallizationproductofNd2Fe23B3phasewasobtainedforthisamorphousalloyannealedat923Kfor300sinthepresenceofanexternalelectricfieldof300kV·m-1(50Hz);whilethecrystallizationproductsareNd1.1Fe4B4,α-Fe,andFe3Bphasesunderthesameannealingconditionexceptforfree-electricfield.Ontheotherhand,thesampleswereannealedat1023K,whichishigherthanthedecompositiontemperatureofmetastableNd2Fe23B3phase,for600s.Inthecaseofthepresenceofanexternalelectricfield,themetastableNd2Fe23B3phase,asamainphase,isstillstayedinthesample.ThisfactsuggeststhattheexternalelectricfieldenhancesthestabilizationofthemetastableNd2Fe23B3phase.Theeffectoftheexternalelectricfieldonthephaseselectionandstabilizationwasexplainedintermsofthespecificconductancedifferencebetweenthecrystallizationproducts.