Figure 1 - uploaded by Alexander Umantsev
Content may be subject to copyright.
Free energy density of a system that can undergo a phase transition as a function of an order parameter. Curves a, b, c correspond to different temperatures: (a) T C <T<T E , (b) T= T E , (c) T> T E . Only b curve is possible for continuous transitions.
Source publication
All stages of phase transformations in materials, nucleation, growth, and coarsening, are subjected to thermal effects that stem from the redistribution of energy in the system like, release of latent heat and heat conduction. The thermal effects change the rate and outcome of the transformation and may result in appearance of unusual states or pha...
Contexts in source publication
Context 1
... equilibrium states η E =Ξ(T) are the extremals of the free energy functional, Eq.(2). The homogeneous part of the equilibrium set η E =Ξ(T) must have at least two minima, η 1 and η 2 , corresponding to stable phases, separated by a maximum, which corresponds to an unstable equilibrium state, η t , called transition state, Figure 1. A few important parameters may be defined for the system: the equilibrium temperature T E -as f(T E , η 1 )= f(T E , η 2 ); the activation barrier height B=f(T E , η t )-f(T E , η 1 ); and the latent heat L=|e(T, η 1 )-e(T, η 2 )| of transformation. ...
Context 2
... discontinuous transitions b≠0 and the equilibrium set η E =Ξ(T) consists of phases with different symmetries, disordered with η α =0 and ordered with η β (T), separated by the transition state η γ (T), which is unstable above T C but gains thermodynamic stability below T C , Figure 2b. The activation barrier B exists at all temperatures above the spinodal one, see Fig.1, the latent heat L does not vanish, and, in accordance with the Gibbs phase rule, the thermodynamic equilibrium between β and α phases is achieved at the specific temperature T E only, see Fig.2b. ...
Context 3
... (16, 17) identify the local interfacial variables V n , K, T_, [T], [dT/du], and relate them to the thermodynamic interfacial quantities, L, σ, ε, Γ s , l I and kinetic properties of the medium like α, m. The beauty of these equations is that they are expressed only through measurable quantities and appropriate thermodynamic parameters of a system and still are applicable to many different situations. ...
Context 4
... interesting and unusual equilibrium thermal effect consists in stabilization of the transition state γ in very small particles of materials that undergo discontinuous transitions. The most striking feature of this effect is that the transition state possesses maximum free energy among all other homogeneous states of the system at the same temperature, see Fig.1. This state was called the adiabatic nanophase (ANP) [17] because stabilization of the transition state is a completely equilibrium effect, which comes about as a result of two mutually assisting constraints: insulation and confinement. ...
Similar publications
Life presents us with problems of varying complexity. Yet, complexity is not accounted for in theories of human decision-making. Here we study instances of the knapsack problem, a discrete optimisation problem commonly encountered at all levels of cognition, from attention gating to intellectual discovery. Complexity of this problem is well underst...
As a result of the increasing use of mobile devices in education, new approaches to define the learning competences in the field of digitally mediated learning have emerged. This paper examines these approach-es, using data obtained from empirical research with a group of Spanish university students. The analysis is focused on the experiences of st...
Accountancy bodies related to education have had influence in the reformulation of curriculum and standard of the discipline of Accounting Theory. The scientific community in turn has discussed in articles and books, the identity of the discipline in the world to assist the consolidation process. One way to verify the identity of a discipline is to...
We investigate whether federal contractors incur political costs in the form of higher tax payments or if they sometimes wield sufficient political power to escape these costs. Our study provides new evidence testing accounting theories regarding political costs in a policy setting increasingly important due to growing government spending and feder...
Access policy violations by organizational insiders are a major security concern for organizations because these violations commonly result in fraud, unauthorized disclosure, theft of intellectual property, and other abuses. Given the operational demands of dynamic organizations, current approaches to curbing access policy violations are insufficie...
