پديد آورنده :
آزادي، مرضيه
عنوان :
ساخت و بررسي خواص ساختاري،مغناطيسي و الكتريكي منگنايت: ﴿La0.5Ca0.5Mn1-xCrxO3(x=0.0,0.002,0.005,0.01,0.03
مقطع تحصيلي :
كارشناسي ارشد
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده فيزيك
صفحه شمار :
[هفت]، 98ص.: مصور، جدول، نمودار
يادداشت :
ص.ع. به فارسي و انگليسي
استاد راهنما :
حسين احمدوند
استاد مشاور :
پرويز كاملي
توصيفگر ها :
پادفرومغناطيس , نظم بار , آلايش كروم , پسماند گرمايي
تاريخ نمايه سازي :
11/3/94
استاد داور :
هادي سلامتي، اسماعيل عبدالحسيني
تاريخ ورود اطلاعات :
1396/10/02
چكيده انگليسي :
105 Investigation of structural magnetic and electrical properties of La0 5 Ca0 5Mn1 xCrxO3 x 0 0 002 0 005 0 01 0 03 manganite Student name Marzieh Azadi Email address m azadi@ph iut ac ir Date of submission 1393 3 19 Department of Physics Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Dr Hossein ahmadvand ahmadvand@cc iut ac irAbstractIn this work we have investigated detailed electrical magnetic and structural studies and thermal hysteresisbehavior on La0 5Ca0 5Mn1 xCrxO3 x 0 0 0 002 0 005 0 01 0 03 manganites Riteveld analysis exhibitedthat all samples are isostructural in Pnma space group at 300 k The experimental result indicate that mother sbody of La0 5Ca0 5MnO3 has very complicated magnetic structure and with 3 percent Cr substitution charg andorbital ordering of pure sample is destroyed Substituation of Cr at Mn site in La0 5Ca0 5MnO3 decreas electricalresistivity and increase metal isulator transition temperature TMI of sample Another significant Cr dopingeffect is unstabilizes the charg ordered state and increases the ferromagnetic metallic FM state with smallamount of substitution The magnetization of pure sample show a counterclockwise hysteresis loop and dopedsamples exhibit a clockwise loop The polycrystalline samples were synthesized by a mechanical method Appropriat amount of La CH3COO 1 5H2O Ca NO3 2 4H2O C4H6MnO4 4H2O C6H7O8 were mixed inproper stoichiometric and preheated at 600oC for 5 h Then samples ground and heated at 800 oC for 10 h Thepowder obtained was annealed at 1000oC for 2 h Finaly the samples were pelletized and heated at 1350 oC for10 h With using powder diffraction patterns we checked phase purity of samples at room temperature Weperformed Ritveld riefinment of the diffraction pattern by using the FULPROF programs magnetization wasmeasured by using ac susceptometr Resistivity measurement were carrid out using prob technique to measurethe dc resistivity between 30 and 300 k Kay words Manganite Thermal hysteresis ac susceptibility Cr doping Charge ordering FM AFM
استاد راهنما :
حسين احمدوند
استاد مشاور :
پرويز كاملي
استاد داور :
هادي سلامتي، اسماعيل عبدالحسيني
