Фазовые превращения в однокомпонентных многофазных системах: фазово-полевой подход

The problems of constructing a multiphase model of the phase field for the processes of phase transitions of the first kind are considered. Based on the Gibbs energy of the complete system expressed in terms of antisymmetrized combinations of phase fields, it is shown that the equations of dissipative dynamics of a locally nonequilibrium system follow from the condition of its monotonic decrease, preserving the normalization of the sum of variables by one and the following properties of the previously known two-phase model.

The Entropy-Based Approach to Physics of Living Systems and the Chaos and Self-Organization Theory

Рассматриваются фундаментальные законы поведения живых систем с позиций классической термодинамики Р. Клаузиуса и Л. Больцмана и термодинамики неравновесных систем I.R. Prigogine. Показывается с позиций новой теории хаоса-самоорганизации, что законы термодинамики невозможно применять к живым гомеостатическим системам на уровне организации этих систем (т. е. на системном уровне), хотя на молекулярном уровне все работает. Одновременно мы не можем использовать и законы термодинамики неравновесных систем. Для гомеостатических (живых) систем неприменима теорема Гленсдорфа–Пригожина о минимуме прироста энтропии P=dE/dt в области (окрестности), где энтропия E имеет максимум (в точках равновесия). Более того, само понятие равновесия в границах термодинамики неприменимо к медико-биологическим системам – системам третьего типа. The fundamental living system behavior patterns are considered in terms of classical Clausius and Boltzmann thermodynamics, and I. R. Prigogine nonequilibrium system thermodynamics. The new theory of chaos and selforganization shows that the laws of thermodynamics are inapplicable to live homeostatic systems at their level of organization (i.e., the system level), although they are perfectly applicable at the molecular level. We cannot use the laws of nonequilibrium system thermodynamics, either. The Glensdorff–Prigogine theorem stating the minimum entropy increase P=dE/dt in the area (vicinity) where the entropy E has a maximum (at the equilibrium points) is inapplicable to homeostatic (living) systems. Moreover, the very concept of nonequilibrium as used in thermodynamics is inapplicable to the systems of the 3rd kind (medical and biological systems).

Автоволны локализованной деформации, индуцированной фазовым превращением

An approach and a model for the nucleation and development of deformation bands and their fronts during plastic deformation due to phase transformation are proposed. A solid is considered as an open nonequilibrium system, the relaxation of which is determined by both vibrational and electronic degrees of freedom. Electronic transitions between different states of a system of nuclei and electrons upon deformation initiate the excitation of an unstable vibrational mode of atomic displacement to positions characteristic of the martensite phase.

Time evolution and thermodynamics for a nonequilibrium system in phase-space

The integrable system is constrained strictly by the conservation law during the time evolution, and the prethermal state from the nearly integrable system is also constrained by the conserved parameters (the constants of motion) with the corresponding generalized Gibbs ensemble (GGE), which is indubitably a powerful tool in the prediction of the relaxation dynamics. For stochastic evolution dynamics with considerable noise, the two-point correlation of local operators (like the density of kinks or transverse magnetization correlators), which do not exhibit the thermal features, display the behaviors of nonthermalization and an asymptotic GGE. In fact it is an asymptotic quasi-steady state with an infinite temperature, therefore the required distance to the nonthermal steady state is in an infinite time average. In this paper, we unambiguously investigate the relaxation of a nonequilibrium system in a canonical ensemble for integrable and nonintegrable systems. Temporal behavior of the many-body quantum system and the corresponding linear-coupling between the harmonic oscillators are discussed. The matrix-method in entropy ensemble is utilized to discuss the boundary and the diagonalization algebraically. The approximation results for nonintegrable system under the considerable perturbations are also presented.

CALCULATION OF THE NONEQUILIBRIUM SYSTEMS CONSISTING OF AN AGGREGATE OF LOCALLY-EQUILIBRIUM SUBSYSTEMS

The basis of SLT is the postulate of nonequilibrium, according to which there is an objective property of matter – “nonequilibrium”, which characterizes the uneven distribution of matter and motion in space. A new formulation of the SLT is given in relation to the set of locally equilibrium subsystems that make up the nonequilibrium system: when real (irreversible) processes occur, the nonequilibrium of the isolated system (IS) decreases, and in reversible processes the nonequilibrium in the system of locally equilibrium subsystems does not change (the increment of one kind of nonequilibrium completely compensated by a decrease in the disequilibrium of some other kind). The maximum work that can be done when the nonequilibrium system goes into equilibrium is considered as a quantitative characteristic of the nonequilibrium system. The article provides a calculated confirmation of the theoretical provisions of the concept of nonequilibrium and its mathematical apparatus by examples of determining the loss of IS disequilibrium during operation of a heat engine performing an irreversible cycle and the nonequilibrium state of an adiabatic system (AS). Schemes of an IS consisting of a hot body, the environment, and a working fluid performing a temperature-imperfect Carnot cycle are given, as well as an AS consisting of the environment and a working fluid, upon expansion of which work is given to an external work receiver. It is shown that the external work of the adiabatic system should be determined not by the decrease in the thermodynamic potential of the working fluid, as is generally accepted, but by the decrease in the potential of all AS bodies (the working fluid and the environment). As a result, analytical expressions are obtained for the practical calculation of nonequilibrium and its reduction during real processes in systems consisting of an aggregate of locally-equilibrium subsystems, which is new in thermodynamics.

The chemical and isotopic compositions of thermal waters and gases in the Republic of Buryatia, Russia

The chemical and isotopic compositions of waters and associated gases in the Republic of Buryatia are investigated in this report. Results show the thermal waters are predominantly enriched in N2. They are alkaline, low salinity and have high concentrations of HCO3-, SO42-, F, Si but low values for Ca2+, Mg2+, K+. According to isotopic composition, the thermal waters are meteoric in origin. Despite the low salinity, the thermal waters are in equilibrium with calcite, magnesite, fluorite, albite, laumontite and other minerals but are not equilibrium with respect to primary aluminosilicates. This indicates that the thermal waters and water-bearing rocks represent the equilibrium-nonequilibrium system.