Vol 61, No 5 (2016)

Excitation of multicomponent trains of coherent optical phonons with different frequencies in monoclinic m-LaVO₄ and tetragonal t-GdVO₄ crystals under impulsive femtosecond SRS-lasing is reported.

The martensite structure of a hardened pseudosingle crystal of grade 37KhN3A medium-carbon structural steel (0.37 wt % C, 1.50 Cr, 3.0 Ni, 0.33 Mn) had the form of coarse packets with dimensions of to 1 cm in the cross section. Every packet was composed of six-orientation martensite crystals arising on one common austenite plane of type {111}. The position of three texture maximums was determined using an X-ray diffractometer for every orientation. In addition, the position of four maximums of retained austenite was found. The periods of martensite lattices and retained austenite as well as the carbon concentration in martensite lattices and near the boundaries are determined.

The equations of dynamics of elastic shells subjected to large deformations are formulated. The Eulerian coordinates on a circular cylinder and time are accepted as independent variables, and one of the unknown functions is the distance from a point of the shell surface to the cylinder axis. The equations of dynamics of nonlinearly elastic shells in the Eulerian coordinates are convenient for exact formulation of the problem on the interaction of strongly deformable shells with moving fluids and gases. The equations obtained can be used for dynamic calculations of fluids and gases flowings in pipelines, blood vessels, hoses, and other nonlinearly deformable thin-walled tubular elements of constructions.

The property to have various representations is investigated for the block elements describing the solutions of boundary-value problems for sets of partial differential equations in the regions with a boundary. These representations have various destinations. One of the representations, which is called packed, is convenient for constructing solutions in block structures on the basis of solutions in separate blocks. Another representation, which is called unpacked, is convenient for a detailed investigation of the properties of solutions in an individual block of the block structure.

In the case of extrusive eruption, we consider the problem on magma degassing which rises in a volcano conduit crossing porous water-saturated rocks. We show that the intensity of outflow of volcanic gases into the rocks is comparable to the intensity of their transport with the rising magma. The magma degassing in the rocks substantially affects the eruption dynamics, in particular, the duration of the periods of eruptive activity.

The problem of determining the phase-space distribution function for the system of the noninteracting dust particles for the mathematical model of cosmic dust Kordylewski clouds—clusters of the non-interacting dust particles in the vicinity of the triangular libration points of the Earth–Moon–Particle system taking into account perturbations from the Sun was considered.