![]() ![]() Hence, the ball-milling time influences also the universality class. The thermodynamic entropy therefore has the dimension of energy divided by temperature, and the unit joule per kelvin (J/K) in the International System of Units (SI). However, for LT-6h, the model changed and the best one became the 3D-Ising model. Entropy change describes the direction and quantifies the magnitude of simple changes such as heat transfer between systems always from hotter to cooler spontaneously. Both LT-1h and LT-3h systems are belonging to the tricritical mean field model. Noting that raising the ball-milling time weakens the RCP. Consequently, the LT sample could be a permanent magnet in a magnetic refrigerator. The relative cooling power (RCP) value in the LT-1h sample at 2 T is 108% (211.758 J kg−1) compared to that of the Gd at 2 T. Since entropy changes are much smaller than enthalpy. Hence, the magnitude of S for a reversible process such as a phase change is calculated. Based on the AC-susceptibility, raising the ball-milling time facilitates the appearance of a spin-glass (SG) state. When a system receives an amount of energy q at a constant temperature, T, the entropy increase S is defined by the following equation. Additionally, it is accompanied with an increase in coercivity and a decrease in the saturation magnetization and remanence. By increasing the ball-milling duration, the proportion of homogeneity is increased, and the material becomes slightly more resilient, according to the Curie-Weiss law. Thus, increasing the ball-milling time of the sample leads to the elevation of TC and does not enhance the magnitude of the magnetization the fact that it affects the magnetic interactions between atoms. The entropy change for a real, irreversible process is then equal to that for the theoretical reversible process that involves the same initial and final states. This transition is around 176, 182, and 183 K accompanied by a decrease in the magnitude in both ZFC and FC data. The Zero-Field-Cooling and Field-Cooling (ZFC/FC) magnetization measurements illustrated that all the systems are presenting a ferromagnetic to paramagnetic phase transition around Curie temperature (TC). According to Williamson-Hall method, as the ball-milling duration is increased, the material's crystallite size decreases from approximately 145 to 99 nm for LT-1h and LT-6h, respectively. We have investigated the ball-milling time effect on different physical properties of La0.6X0.1Te0.3MnO3 (X is a lacuna) system (LT) milled for 1 h (LT-1h), 3 h (LT-3h), and 6 h (LT-6h). La0.6X0.1Te0.3MnO3 system with significant refrigerant capacity at low magnetic field and double magnetic entropy change peaks: effect of ball-milling time on physical and critical behaviors Authors: Show that the entropy change in the cyclic process of an ideal gas that include an isobar, an isochor, and an isotherm is zero. ![]()
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