On estimating the magnetocaloric effect from magnetization measurements
On estimating the magnetocaloric effect from magnetization measurements
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DOI：
10.1016/j.jmmm.2009.06.013
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发表时间：
2010-05-01
影响因子：
2.7
通讯作者：
Amaral, V. S.
中科院分区：
文献类型：
--
作者：
Amaral, J. S.;Amaral, V. S.
我们解决的各个方面，一个stimating从磁化测量的磁热效应，并使用一个麦克斯韦关系在第一和第二阶相变，包括（a）使用磁化作为一个热力学变量在一个不均匀的情况下（结构或化学分布，磁畴）和（B）非平衡条件（不可逆性）的第一阶相变，包括混合相条件。我们发现，麦克斯韦方程或任何其他方法，如面积微分应谨慎使用，而不是包括在一个平衡，这可能会导致虚假的结果。利用朗道和平均场理论等方法模拟一阶和二阶磁相变的磁熵变，有助于更好地理解磁熵变中常见的异常峰的性质及其物理相关性。(C)2009爱思唯尔有限公司版权所有。
We address various aspects one stimating the magnetocaloric effect from magnetization measurements, and the use of a Maxwell relation in first-and second-order phase transitions, including( a) the use of magnetization as a thermodynamic variable in an inhomogeneous situation (structural or chemical distributions, magnetic domains) and (b) non-equilibrium conditions (irreversibility) on first-order phase transitions, including mixed-phase conditions. We find that the Maxwell equation or any other methods such as area differentiation should be used with caution and not included at a out of equilibrium, which can lead to spurious results. The use of methods for modeling the magnetic entropy change of first- and second-order magnetic phase transitions, such as Landau and mean-field theory, can be helpful to better understand the nature of the commonly found anomalous peaks in magnetic entropy change and their physical relevance. (C) 2009 Elsevier B.V. All rights reserved.