arXiv subjects

Vladimir Kh. Dobruskin

Publications and source records attributed to Vladimir Kh. Dobruskin.

5 recordsLinked to original sources

arXiv2022

Impact of humanity on climate change

The thermodynamic approach shows that the total energy produced by humanity disrupts the thermal balance of the planet and causes counteraction, that is, climate change, which can slow down the progress of civilization. This outcome not only confirms the consensus on the role of humanity in climate change, but also quantifies it. The calculation of the average temperature of the Earth is based on its energy balance and includes the application of the Stefan-Boltzmann equation. The confusion in the use of the equation was discovered and clarified; the boundaries of application of the Law was outlined. The application of the Stefan-Boltzmann equation shows that the energy produced by humanity is responsible for about half of the magnitude of global warming. This result should have a strong impact on environmental decision-making

physics.ao-ph↗

arXiv2021

Thermodynamics approach to near future of civilization

The purpose of this study is to consider the near future of civilization in the framework of thermodynamics. Kardashev's proposal to evaluate the development of celestial civilizations by the amount of energy they are able to use was adopted to translate the concept of human activity into the language of physics. The discussion is limited to considering the last 500 years of history from the beginning of the scientific and technological revolutions to our immediate future. The application of classical and nonequilibrium thermodynamics is discussed. In the framework of classical thermodynamics, two systems are compared: a) the first is a hypothetical quasi-equilibrium system, Earth without a population. Since biological evolution becomes almost imperceptible for a short period of time, such a system remains in the same pristine state for the entire period; (b) the second is our habitable planet, which is not in equilibrium due to rapid anthropogenic evolution and can be considered as a combination of the first system with human civilization. It is shown that in response to the development of civilization (a) the equilibrium of the hypothetical system is disturbed and processes are initiated aimed at reducing the amount of energy produced, and (b) there is a maximum on the path of civilization development over time. The resistance of nature will continue until a new balance is established, corresponding to a lower level of energy production. The central problem is whether humanity is ready and able to agree on a new balance, otherwise the degradation of our planet can lead to the collapse of civilization.

physics.soc-ph↗

arXiv2010

Physicochemical Perturbations of Phase Equilibriums

The alternative approach to the displacement of gas/liquid equilibrium is developed on the basis of the Clapeyron equation. The phase transition in the system with well-established properties is taken as a reference process to search for the parameters of phase transition in the perturbed equilibrium system. The main equation, derived in the framework of both classical thermodynamics and statistical mechanics, establishes a correlation between variations of enthalpies of evaporation, Δ(ΔH), which is induced by perturbations, and the equilibrium vapor pressures. The dissolution of a solute, changing the surface shape, and the effect of the external field of adsorbents are considered as the perturbing actions on the liquid phase. The model provides the unified method for studying (1) solutions, (2) membrane separations (3) surface phenomena, and (4) effect of the adsorption field; it leads to the useful relations between Δ(ΔH), on the one hand, and the osmotic pressures, the Donnan potential, the surface curvature, and the pore structure, on the other hand. The value of Δ(ΔH) has a clear physical meaning and gives a new insight into our understanding of the apparently different phenomena. The model is applicable if the change between entropies of the comparable gas phases is far more than the difference between entropies of the liquid phases.

physics.chem-ph↗

arXiv2010

Effect of Chemical Composition on Enthalpy of Evaporation and Equilibrium Vapor Pressure

Proceeding from the Clausius-Clapeyron equation, the relation is derived that establishes a correlation between the partial enthalpy of evaporation from binary solutions, concentrations of components, and equilibrium vapor pressures. The difference between enthalpies of evaporation of components from solutions and those from the pure liquids, D(DH), depends on the chemical nature and concentrations, X, of solutions. The effect of concentrations on D(DH) makes different appearances in ideal and non-ideal solutions, although, as a whole, D(DH) increases with the growth of concentration of the second component. A model is introduced, which considers D(DH) as the sum of energetic changes of three sequential stages: passage of molecules from the bulk liquid into the surface layer, exit of the molecules on the outer side of the interface, and the following desorption into the gas phase. In the framework of the model, the main contribution to enthalpy of evaporation comes from the processes in the surface layer. It is suggested that adsorption from solutions, which changes the chemical composition of the surface layer with respect to that of the bulk solution, determines, to great extent, the difference in the forms of the curves D(DH)=f(X) for ideal and non-ideal solutions.

physics.chem-ph↗

arXiv2008

Size Dependent Phase Transitions

The contributions of heat and work in generating a new surface area are considered. Unlike the classical theory of vapor/droplet equilibrium, which associates changing surface areas with work done against the surface tension, an alternative approach assumes that the droplets grow due to a controllable condensation of vapor and the internal energy of droplets changes due to the heat of the phase transition, and not due to the mechanical work. The effect of radii on the internal energy is discussed. The theory of the vapor/droplet equilibrium is constructed on the basis of the fundamental Clapeyron equation. When droplet radii exceed about 50 Lennard-Jones' molecular diameters, the classical and new models yield similar values of thermodynamic parameters, but differ essentially in the range of the finest clusters and nanocapillaries. In contrast to the Kelvin equation, which is not applicable for adsorption in micropores with radii less than 1 nm and fails in its description of hysteresis loops in mesopores, the present approach is in reasonably good agreement with observations; the model gives rational explanations to the mechanism of a droplet growth and critical parameters of nucleation.

cond-mat.soft↗