電子束輻照合成納米磁性材料.pdf

1、上海大學(xué)碩士學(xué)位論文電子束輻照合成納米磁性材料姓名：何林鋒申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：應(yīng)用化學(xué)指導(dǎo)教師：周瑞敏20050301Abs仃actInthispaperanewmethod，usingelectronbeam，hasbeensuccessfullydevelopedtosynthesizemagneticnanometermetalmaterials，includingnickelnano—particles，cobaltllan

2、o—particlesandironnanoparticles，andsomeoftheirpropertieshavebeentestedNanoparticlescanbesimplypreparedbyelectronbeamgeneratedfromindustrialelectronbeamacceleratorfromaqueoussolutionsoftheirsaltatambientpressureandroomtem

3、peraturewithouttheaddifionofanycatalystThestructure，morphology，size，sizedistribution，opticalproperties，magneticpropertiesandthemeltingpointhavebeencharacterizedbyX—raydiffraction(XRD)，laserscatteringparticlesizedistribut

4、ionanalysis(LSPSDA)，transmissionelectronmicroscopy(TEM)，ultravioletvisiblespectrophotometer(VSM)anddifferentialscanningcalorimeter(DSC)，respectivelyIntheexperiment，theaverageparticlesizeandtherateyieldofnano—materialswer

5、einfluencedbytheconcentrationofmetalion，pHofthesolution，theconcentrationofsurfactantandtheradiationdoseNanoparticlenickelandnano—particlecobaltwerepreparedsuccessfullybyelectronbeamgeneratedbyelectronbeamacceleratorfromt

6、heinorganicsalt，nickelsulfate(NiS046H20)andcobaltsulfate(COS04‘7H20)inawatersystemusingpolyvinylalcohol(PVA)assurfaceactiveagentandisopropylalcohol(IPA)asscavengerofoxidativeradicalsTheaveragesizeofnickelnano—particlesan

7、dcobaltnano—particlesareabout39rimand32nmrespectively’Nanocrystallineferrousferricoxide，F(xiàn)e304powders，hasbeenpreparedbyelectronbeamfromferricsulfateaqueoussolutionInexperimenttheproductsdidnotdependonthepHofthesolutionund

8、erthehighirradiationdosebyelectronbeamAfterreductionbypurehydrogen，nanoparticleironwasobtained，whichexhibitslowremanenceandcoercivityatambienttemperature，indicatingthatitbelongstothecubiccrystalsystemnlemagneticpropertie

9、softhepowdersrevealedthattheironissuperparamagneticnlereductiontemperaturewasfoundtoaffecttheparticlesizewhenthereductiontemperatureofferrOUSferricoxidewas5lO℃theaveragesizeoftheironpowderproduct，isabout34nmInaddition，at

10、thesameradiationdose，withinacertainrangeduringtheirradiationofcobalt，higheryieldrateWasobtainedundermovableconditionsthanwhenthesolutionswerestaticKeywords：nano—nickel；nanocobalt；llanoiron；electronbeamirradiation；electro