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The behavior of hydrogen molecules in carbon nanopores of different shapes (slit-shaped, cylindrical, and spherical) is investigated using the molecular dynamics method. It is shown that an adsorbed molecular layer with increased density is formed near the nanopore walls, and dynamic equilibrium is established between this layer and the gas in the central region of the nanopore. The distribution of the density of gas molecules over the cross section is found to depend on the size and wall curvature of nanopores: with a reduction in the nanopore size, the density of the adsorbate increases more rapidly in spherical nanopores, whose walls are characterized by greater mean curvature.

A molecular-dynamic study of nucleation of structural defects in materials with an initially perfect crystal lattice by thermal fluctuations under high strain rates is performed. It is shown that thermal fluctuations can generate structural defects. There exists some threshold value of strain at which abrupt growth of regions with local structural changes is observed.

A constitutional function for a bistable cellular automaton is presented which is universal for numerous processes. The bistable cellular automaton formalism was used to describe the propagation of a combustion (switching) wave in a chemically active medium. The calculated dependence of front velocity on the initial state and properties of a system was used to describe the synthesis of Ni3Al in a powder mixture. The calculated results were in good agreement with experimental data. The relationships obtained permit calculation of the important technical parameters for synthesis in the combustion regime.

Impurity behaviour (both thermodynamic and mechanic properties) are investigated under pressure and shear application. The conditions are found of shear instability occurrence — the critical temperature θc and critical shear stress τc. θc decreases with shear stresses application and τc decreases with temperature growth. The used Green's functions method could be applied for the different cases of atomic Hamiltonians and for the different types of mechanical loading. Das Storstellenverhalten (sowohl thermodynamische als auch mechanische Eigenschaften) unter Druck und Scherung wird untersucht. Bedingungen fur das Auftreten von Scherungsinstabilitat, die kritische Temperatur θc und die kritische Scherspannung τc werden gefunden. θc nimmt mit der Scherspannung ab und τc nimmt mit steigender Temperatur ab. Die benutzte Methode der Greenschen Funktionen last sich fur verschiedene Falle atomarer Hamiltonians und fur die verschiedenen Arten der mechanischen Belastung anwenden.

Molecular dynamics techniques are used to show that heat can be transferred ballistically in threedimensional crystalline materials at temperatures on the order of Debye temperatures.

Atomic structure changes of a crystal induced by shock waves are studied by molecular dynamic method. α-Fe crystallites are used for simulation having a rectangular area in the (110) plane and containing about 104 atoms. The radial distribution function of atoms is shown to lose its discrete form, typical of a crystal and to become continuous when the shock wave planar front is distorted. Microfragmentation in the corresponding areas of a crystal is shown at the same time to be the result of the shock wave distortion with a planar front. [Russian Text Ignored].