Особенность в точке перехода от равновесной к метастабильной фазе металлического расплава
The quantum nuclear effects are studied in water using centroid molecular dynamics (CMD) method. The aim is the calibration of CMD implementation in LAMMPS. The calculated intramolecular energy, atoms gyration radii and radial distribution functions are shown in comparison with previous works. The work is assumed to be the step toward to solution of the discrepancy between the simulation results and the experimental data of liquid n-alkane properties in our previous works.
The small number of dust particles in the system and their large kinetic energy make it impossible to use the notion of “temperature” to describe the dynamics of dust particles in gas discharge without substantiation. We simulated the isolated and open systems of dust particles based on the molecular dynamics method and suggested the substantiation of applying the term “temperature” to describe the dynamics of the system of dust particles in the gas discharge plasma. The closeness of the equilibrium velocity distribution for a small number of particles and the Maxwell distribution for isolated and open systems is shown. It is found that the average kinetic energy precisely coincides with the velocity distribution parame ter of the dust particles. The necessity of separation the temperature of the horizontal motion and the temperature of the vertical motion of dust particles is shown.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.