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Victor Kurasov

Publications and source records attributed to Victor Kurasov.

At least 19 recordsLinked to original sources
arXiv2013

Non stationary nucleation: the model with averaged velocity

A new model to calculate the rate of nucleation is formulated. This model is based on the classical nucleation theory but considers also vapor depletion around the formed embryo. The key characteristic which arises in frames of this theory is the mean time of the embryo formation. On the base of this time the probability to observe the embryo formed during the given time is estimated which allows to construct a simple approximate theory.

cond-mat.stat-mech↗
arXiv2013

Non stationary nucleation: the model with minimal environment

A new model to calculate the rate of nucleation is formulated. This model is based on the classical nucleation theory but considers also vapor depletion around the formed embryo. As the result the free energy has to be recalculated which brings a new expression for the nucleation rate.

cond-mat.stat-mech↗
arXiv2010

Late periods of the condensation process

The full evolution during the late periods of the condensation process is described in the analytical form. The process is split into several periods and for every period the simple approximate solution is given.

cond-mat.stat-mech↗
arXiv2008

Variations of parameters in nucleation process under different external conditions

The nucleation process under different external conditions is considered. It is shown that the duration of this process can be connected with the microscopic corrections to the free energy of the critical embryo. Connection between variations in the value of the critical embryo free energy and the duration of the nucleation stage is given for several types of external conditions. This connection is in some cases reciprocal to uncertainty relation in quantum theory. In Appendix the derivation of main features of the general theory on the base of restrictions coming from the possibility of effective and stable observations is given.

cond-mat.stat-mech↗
arXiv2007

Theoretical description of nucleation in multicomponent system

The full theoretical analysis of the kinetics of multicomponent nucleation is presented. The relief of the free energy with surface excesses was analyzed, the valleys and ridges were described, their mutual interaction was studied. The new possibility to change the valley of nucleation is shown. The possibility to have one common valley instead of several neighbor ones which leads to the radical change in the height of the effective activation barrier and to the new value for the nucleation rate.

cond-mat.stat-mech↗
arXiv2007

Effective interaction of exhausted regions in kinetics of nucleation

An effect of overlapping of exhausted regions around droplets of a new phase is analyzed. Several approximation to take overlapping into account are suggested. The small parameter responsible for convergence is extracted. The multi particle effects of overlapping are described.

cond-mat.stat-mech↗
arXiv2005

Stochastic effects in the growth of droplets

The effects of stochastic absorption and ejection of molecules by growing droplets have been considered. Both analytical and numerical approaches have been used. They demonstrate the satisfactory coincidence. It is proved that in general case corresponding to the asymptotic at big numbers of molecules in the critical embryo the effects of stochastic growth are small in comparison with the effects of stochastic appearance of droplets.

cond-mat.stat-mech↗
arXiv2005

Some properties of evolution equation for homogeneous nucleation period under the smooth behavior of initial conditions

The properties of the evolution equation have been analyzed. The uniqueness and the existence of solution for the evolution equation with special value of parameter characterizing intensity of change of external conditions, of the corresponding iterated equation have been established. On the base of these facts taking into account some properties of behavior of solution the uniqueness of the equation appeared in the theory of homogeneous nucleation has been established. The equivalence of auxiliary problem and the real problem is shown.

cond-mat.stat-mech↗
arXiv2004

Dispersion of nucleation under the smooth variation of external conditions

A simple method to calculate dispersion of the total number of droplets appeared in the process of nucleation caused by the smooth variation of external conditions has been presented. The analytical result for dispersion is compared with results of numerical simulations and the coincidence has been observed. The role of stochastic appearance of several first droplets in formation of dispersion has been analyzed.

cond-mat.stat-mech↗
arXiv2004

Corrections to a mean number of droplets in nucleation

Corrections to a mean number of droplets appeared in the process of nucleation have been analyzed. The two stage model with a fixed boundary can not lead to a write result. The multi stage generalization of this model also can not give essential changes to the two stage model. The role of several first droplets have been investigated and it is shown that an account of only first droplet with further appearance in frame of the theory based on the averaged characteristics can lead to a suitable results. Both decay of metastable phase and smooth variations of external conditions have been investigated.

cond-mat.stat-mech↗
arXiv2004

Explicit two cycle model in investigation of stochastic effects in diffusion regime of metastable phase decay

The theory for manifestation of stochastic appearance of embryos in the global decay of metastable phase has been constructed. The regime of droplets growth is supposed to be both free molecular one and diffusion one. The deviation for a mean droplets number from the value predicted by the theory based on averaged characteristics have been calculated. The value of dispersion for the distribution of the total droplets number in particular attempt has been also calculated analytically. Comparison with results of numerical simulation has been given and the correspondence between simulation and analytical approximate results is rather good.

cond-mat.stat-mech↗
arXiv2003

Kinetic effects of multi-component nucleation

The process of multicomponent condensation is considered. The theory taking into account several channels of nucleation is constructed. The analytical approximate description of the whole condensation process is given. The specific phenomena of the secondary nucleation is described analytically. The possibility of the partial reverse condensation is discussed.

cond-mat↗
arXiv2003

Kinetics of nucleation for the decreasing rate of the new embryos growth

Kinetics of the first order phase transition is investigated. In some rather wide spread situations the property of avalanche growth of the objects of a new phase doesn't take place. This radically complicates the theoretical description of the nucleation kinetics and this case was completely investigated here. The power-like dependencies with decreasing absolute value of derivative on time were chosen as the model laws of embryos growth. All main characteristics of the nucleation period including the spectrum of sizes of the new phase objects were obtained. An analytical approximate description of nucleation in different external conditions was fulfilled. The errors of such description are found and proved to be small.

cond-mat↗