The Basic Theorem of Temperature-Dependent Processes

Abstract

The basic theorem of isokinetic relationships is formulated as “if there exists a linear correlation “structure∼properties” at two temperatures, the point of their intersection will be a common point for the same correlation at other temperatures, until the Arrhenius law is violated”. The theorem is valid in various regions of thermally activated processes, in which only one parameter changes. A detailed examination of the consequences of this theorem showed that it is easy to formulate a number of empirical regularities known as the “kinetic compensation effect”, the well-known formula of the Meyer–Neldel rule, or the so-called concept of “multi-excitation entropy”. In a series of similar processes, we examined the effect of different variable parameters of the process on the free energy of activation, and we discuss possible applications.

Parameter Variability in Viscous Convection

“…Obviously, there is no fit between model results and measured time series. The overall development is obviously correct, but its dynamics are much too slow, in two respects: (1) The transition from an initial phase with an almost constant temperature to a dynamic phase with strong gradients appears too late, with the exception of cooling in point A; (2) the gradients in the dynamic phase are smaller than the ones in the observed data. Moreover, the model cannot reproduce the peculiar behavior of the temperature curve at point B in the cooling experiment.…”

“…with activation energy E a and Boltzmann constant k B [2]. The coefficient ς 0 in formula (0) depends on the reference temperature.…”

Dynamic Character of Thermal Analysis Where Thermal Inertia Is a Real and Not Negligible Effect Influencing the Evaluation of Non-Isothermal Kinetics: A Review

“…At present, non-isothermal kinetics has become the focus of attention, with a number of review papers published [82][83][84][85], but with almost none of them questioning the influence of thermal inertia as one of the missing key factors. Thermo-analytical methods that actually deal with heat transfer and the inclusion and description of this transfer in the standard thermo-analytical literature are so far mostly absent.…”

“…The articles describing the transfer imbalance due to heating are sporadic [77][78][79][80][81], as also are discussions on the correct determination and interpretation of thermo-analytically off-equilibrium temperature [45]. Therefore, a rather more detailed depiction and transfer of the thermal problem to the pages of journals is required that directly deals with heat transfer [31,53,79,80]; this has still been lacking in traditional thermo-analytical journals and so we gladly welcomed the new thermo-journal attitude [84].…”

Entropy and Isokinetic Temperature in Fast Ion Transport

“…From Equation ( 14 ), one may see that, in addition to the entropy, the prefactor is affected by many parameters, including the mobile ion concentration, ion jump distance, and attempt frequency. Therefore, it is worth noting that MNR applies only to “closely related systems”, when the material candidates have similar composition and structure, so that other parameters do not differ much between different samples or for variable measurement parameters, as discussed in the literature on chemical reactions [ 24 , 25 , 35 ] and in the previous and following sections. However, when the ion concentration changes, the defect formation energy may also vary, causing changes in the activation energy.…”