【摘 要】
:
The polycrystalline samples of Pr0.45(Ca1-xSrx)0.55MnO3 (x =0.0,0.2,0.4,0.6) were prepared by solid-state reaction.Influence of Sr2+ substitution for Ca2+ at A
【机 构】
:
Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-materials Research,Department of El
【基金项目】
:
the National Natural Foundation of China;the Natural Science Research Key Program of Anhui Educational Committee;the Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-materials Research
论文部分内容阅读
The polycrystalline samples of Pr0.45(Ca1-xSrx)0.55MnO3 (x =0.0,0.2,0.4,0.6) were prepared by solid-state reaction.Influence of Sr2+ substitution for Ca2+ at A site on magnetism was studied through the measurements of X-ray diffraction (XRD) spectrum,the magnetization-temperature (M-T) curves and electron spin resonance (ESR) curves.The results show that the magnetism strengthens and charge ordering weakens gradually with the increase of Sr2+ substitution amount,respectively.The transition of paramagnetism(PM)-antiferromagnetism(AFM) occurs below the transition temperature of charge ordering (Tco),and there is little ferromagnetic phase in the antiferromagnetic background at the lower temperature,which results in complex magnetic phases of the samples.Ferromagnetic clusters appear and grow larger with the increase of substitution amount.In addition,the reentrant spin-glass behavior appears at about 41 K.The magnetism phenomenon of the samples is mainly due to the competition between double exchange and Jahn-Teller coupling.The Jahn-Teller coupling becomes weak,and the double exchange wins the advantage in the competition with the increase of substitution amount,which leads to the magnetism variation of the system.
其他文献
为推动区域协调发展,逐步缩小区域发展差距,必须注重高职教育发展,引导高职教育跨区域合理流动,引进先进教学设备和高精尖技术人才,这是高职教育为经济发展作贡献的基本途径
The robust guaranteed cost sampled-data control was studied for a class of uncertain nonlinear systems with time-varying delay.The parameter uncertainties are t
输电网规划设计的电网工程全寿命周期成本分析可以使得电网项目在实现全寿命周期内经济、社会、环境等成本最低,综合效益最优,具有全系统、全费用、全过程,即"三全"的特点。本文
A reproducing kernel collocation method based on strong formulation is introduced for transient dynamics. To study the stability property of this method, an alg
The selective catalytic reduction reaction belongs to the gas-solid multiphase reaction,and the adsorption of NH3 and NO on CuO/y-Al2O3 catalysts plays an impor
±800kV楚雄换流站SVC装置调试阶段发现TCR电抗器运行产生的磁场,严重影响到其周围设备的安全运行,为解除隐患采取了地网解环和抬高电抗器的措施。本文对采取的措施和实施效果
The synthesis of Al2O3-coated and uncoated LiMn2O4 by solid-state method and fabrication of LiMn2O4/graphite battery were described.The structure and morphology
The microstructural evolution and interfacial reaction of the Au/Sn/Au/Sn/Au/Sn/Au couples were investigated during annealing at 453,523,and 543 K for up to 240
The microstructure of the as-cast 7A55 aluminum alloy and its evolution during homogenization were investigated by means of optical microscopy (OM),scanning ele
In order to verify the validity of finite element numerical simulation method for asphalt mixture,which consists of aggregates,mastic (where mastic is a kind of