熱電氧化物（Ca-,3-Co-,2-O-,6-）-,1-x-（Ca-,3-Co-,4-O-,9-）-,x-體系的正電子湮沒(méi)研究.pdf

1、河南師范大學(xué)碩士學(xué)位論文熱電氧化物（CaCoO）（CaCoO）體系的正電子湮沒(méi)研究姓名：王海英申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：凝聚態(tài)物理指導(dǎo)教師：路慶鳳20050501AbstractWehaveprepared(Ca3C0206)。(C83C0409)I“x=0，01，02，O3，O4，O5，O6，O7，O8，09，10)by“rapidheatingprocedure’’andinVestigatedseriesofsamplesusing

2、XRD、SEMtechniquesanddiscussedthetransitionDrocedurefromc83c0206toCa3C0409andtherelationshipbetweenposi訂onlifetimeandcrystalconversionTheresuItofXRDshowedthesamplescrystalweSamplesfromx_O1tox_09existnootherxRDpeakexceptc8

3、3c0206andc83c0409phasesFromsEMfigurewecanseethatca3C0206hasshon_barstructurewithallkindsofdjrectionsandCa3C0409hasnakystmcturewhichjsparalleltothesurf配eBecauseoftheirdi仃erentorginalreactionpowder，samples’crystalformandsi

4、zeofdefectsofSEMfromx=o1tox=09changedreguI盯lyltjndicatesthatcrystaIIineanddefectdens時(shí)haslargechange啦ersimeringinmesamesime卜temDeratureandsintertimenthiswork，wecalculateposiIronbulklifetimerl，(freelifetimeorBLOCH1ifetime)

5、，aVerage1ifetimef^VelectIDndensityneanddensityofdefectnumberCvWithxincreasjng行eelifetimeV抓esslowlyC印tured1ifetimer2increaSessIowlynrstandcomejtspeakatx=O5，thenCaptured1ifetjme砭decrcasesslOwlyfromx_05tox_10samplesAtthesan

6、letime，wefounditaRercalculationthatposjtmnbulklifetimerIl，aVeragelifetimer^’，electrondensityncanddensityofdefectnumbercvformpeakontheoccasionof5#、6#phase廿ansitionbecauseofdefectse師cientintroductionThisphenomenonistightly

7、connectedwiththosetwosubstances，Ca3c0409“，odimensionnakyC0021ayerstructureandCa3C0206onedimensionchainstructure，whjchhavespecaI咖sponpropertiesandstructuresKeywords：positronannihjlationspectra；Xraddiffractjon；scanningelec