Biomedical subjects

LM Pismen

Publications and source records attributed to LM Pismen.

18 recordsLinked to original sources

PubMed2000

Interaction of vortices in a complex vector field and stability of a "Vortex molecule"

We consider interaction of vortices in the vector complex Ginzburg-Landau equation (CVGLE). In the limit of small field coupling, it is found analytically that the interaction between well-separated defects in two different fields is long ranged, in contrast to the interaction between defects in the same field which falls off exponentially. In a certain region of parameters of CVGLE, we find stable rotating bound states of two defects-a "vortex molecule."

Journal Article↗

PubMed2000

Disjoining potential and spreading of thin liquid layers in the diffuse-interface model coupled to hydrodynamics

The hydrodynamic phase field model is applied to the problem of film spreading on a solid surface. The disjoining potential, responsible for modification of the fluid properties near a three-phase contact line, is computed from the solvability conditions of the density field equation with appropriate boundary conditions imposed on the solid support. The equations describing the motion of a spreading film are derived in the lubrication approximation (in the limit of small contact angles). In the case of quasiequilibrium spreading, it is shown that the correct sharp-interface limit is obtained, and sample solutions are obtained by numerical integration. It is further shown that evaporation or condensation may strongly affect the dynamics near the contact line, and that it is necessary to account for kinetic retardation of the interphase transport to build up a consistent theory.

Journal Article↗

PubMed2000

Dynamic quasicrystalline patterns: wave-mode-turing-mode resonance with turing-mode self-interaction

We study perturbatively the effect of resonant Turing-mode interactions on the slow time evolution of quasicrystalline patterns sustained by resonant interaction between wave and static composite modes. We find that stabilization of quasicrystalline patterns by quadratic wave-mode-Turing-mode interactions is possible even under the action of weak destabilizing Turing-mode self-interactions.

Journal Article↗

PubMed2000

Crystallization kinetics and self-induced pinning in cellular patterns

Within the framework of the Swift-Hohenberg model it is shown numerically and analytically that the front propagation between cellular and uniform states is determined by periodic nucleation events triggered by the explosive growth of the localized zero-eigenvalue mode of the corresponding linear problem. We derive an evolution equation for this mode using asymptotic analysis, and evaluate the time interval between nucleation events, and hence the front speed. In the presence of noise, we find the velocity exponent of "thermally activated" front propagation (creep) beyond the pinning threshold.

Journal Article↗

PubMed1995