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Z Kozísek

Publications and source records attributed to Z Kozísek.

4 recordsLinked to original sources
PubMed2006

Size distribution of nuclei in a closed system.

Kinetic equations describing the formation of nuclei from a supersaturated vapor in a closed system are solved numerically to determine the size distribution of nuclei at various times. Depletion of vapor phase during phase transition process is taken into account. Evolution of the size distribution of nuclei is analyzed. Due to the decrease of the supersaturation of the vapor phase, a maximum appears in the size distribution of nuclei, which disappears at sufficiently long time. Supersaturation of the mother phase decreases to a value close to 1.

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PubMed2005

Duration of nucleation process in supercooled halide melts.

We present a model allowing to estimate the so-called time lag of nucleating halide melts using electrical conductivity measurements. Due to the complex-forming nature of molten halide salts we suppose two basic types of charge carriers in the melt: complexes (playing the role of monomers-building units) and clusters of a newly forming solid phase. Within context of the nonstationary nucleation theory we determined a formula expressing the time dependency of electrical conductivity of such a system and compared this result with the experimental data obtained for the melts of PbBr2, PbCl2, and KPb2Cl5. In terms of this formula the time lag of nucleation may be estimated. This important quantity characterizing the moment from which the nucleated clusters only grow to the macroscopic sizes has been found to be approximately 75% of the total duration of the nucleation process itself.

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PubMed1999

Analytical approach to time lag in binary nucleation.

We present an analytical formula for the time required to establish steady state in a nucleating binary system. To test our solution, we evaluate the time lag for a range of activities of both components at the vapor-liquid transition, and show that our result is in much better agreement with a purely numerical simulation than other available analytical formulas, which overestimate the time lag by factors of from 2 to 200.

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