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la{0.67-x}ca{0.33}mno{3}系列样品的磁热效应

Keywords: 无机非金属材料,锰钙钛矿,磁致冷,磁热效应

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Abstract:

?用溶胶--凝胶法制备了不同空位浓度掺杂的la$_{0.67-x}$ca$_{0.33}$mno$_{3}$系列样品($x$=0.00,0.02,0.06,0.10),用扫描电子显微镜(sem)观察了样品的形态和颗粒大小,x射线衍射实验结果显示样品为单相钙钛矿结构,用振动样品磁强计(vsm)测量了样品的磁化强度随温度变化的$m$--$t$曲线和起始磁化$m$--$h$曲线.研究了空位浓度对样品的居里温度$t_{\rmc}$和磁熵变的影响.结果表明,空位浓度的掺杂将样品的居里温度$t_{\rmc}$提高至室温附近,磁熵变得到增强.对于经历了一级相变的样品la$_{0.67-x}$ca$_{0.33}$mno$_{3}$($x$=0.02),在居里温度$t_{\rmc}$(277k)附近和1t外磁场下,最大磁熵变达到了2.78j/(kg$\cdot$k).

References

[1]  1igorsevostianov,markkachanov,connectionbetweenelasticmoduliandthermalthermalconductivitiesofanisotropicshortfiberreinforcedthermoplastics:theoryandexperimentalverification,materialsscienceanden-gineering,360,339(2003)
[2]  4wanghaiying,shangjialan,liuguoquan,overviewondescriptionmethodsforthespatialdistributionofthesecondphaseinmulti-phasematerials,advancesinme-chanics,30(4),558(2000)(汪海英,尚嘉兰,刘国权,复相材料中第二相的空间分布状况的描述方法综述,力学进展,30(4),558(2000))
[3]  5y.t.zhu,g.zong,a.manthiram,strengthanalysisofran-domshort-fibre-reinforcedmetalmatrixcompositemate-rials,j.mater.sci.,29,6281(1994)
[4]  2j.s.bergstrom,l.b.hilbertjr.,aconstitutivemodelforpredictingthelargeeformationthermomechanicalbe-havioroffluoropolymers,mechanicsofmaterials,37,899(2005)
[5]  3zengqingdun,memo-destructionandintensityofcom-posites(beijing,sciencepublishingcompany,2002)p.52(曾庆敦,复合材料的细观破坏机制与强度(北京,科学出版社,2002)p.52)
[6]  6liuminshan,sunaifang,dongqiwu,thermalcon-ductivecompositecompactplate-shellheatexchanger,prcpat.200610128280.x,2006(inchinese)(刘敏珊,孙爱芳,董其伍,导热复合材料紧凑型板壳式换热器,中华人民共和国发明专利,200610128280.x,2006)
[7]  7sunaifang,liuminshan,dongqiwu,modificationandapplicationsituationofptfeinanticorrosiveheatexchanger,materialsformechanicalengineering,31(9),1(2007)(孙爱芳,刘敏珊,董其武,耐腐蚀换热器用聚四氟乙烯的改性与应用现状,机械工程材料,31(9),1(2007))
[8]  8v.a.shelestova,v.v.serafimovich,p.n.grakovich,theef-fectofthesizeofcarbonfibersonthephysicomechanicalpropertiesoffluviscomposites,mechanicsofcompositematerials,38(2),125(2002)
[9]  9akihirooshima,akiraudagawa,shigerutanaka,fabri-cationofpolytetrafiuoroethylene/carbonfibercompositesusingradiationcrosslinking,radiationphysicsandchem-istry,62(1),77(2001)
[10]  10p.n.grakovich,v.a.shelestova,plasma-chemicalmodifi-cationofcarbonfibersasanefficientmethodofregulat-ingpropertiesofptfe-basedcompositematerials,sci-encechina,a,44(s1),292(2001))

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