Vol 61, No 3 (2016)

On the basis of the use of the generalized (natural) coordinates for the description of electrons and nuclei and the representation of a molecule as a stable geometrical figure, where the electrons and nuclei interact by Coulomb’s law, while nuclei with nuclei interact elastically, a Hamiltonian describing simultaneously the electron and vibrational states and the rotations of a molecule as a whole is proposed.

A generator of turbulent electron beams in an independent mode and in the mode of amplification of an external single-frequency signal is experimentally investigated. The formation of higher harmonic components in the spectrum of output radiation of the generator is shown experimentally. The phenomenological model of the turbulent electron flow is constructed on the basis of a chain of interacting “electron vortices” described by the modified nonlinear Van-der-Pol differential equations. The modes of independent dynamics and the mode of amplification of an external harmonic signal are considered. The results of numerical modeling and experimental investigations are compared. The qualitative correspondence of the behavior of the dependences obtained from the experimental investigation of the generator of turbulent electron beams and the results obtained from numerical modeling is shown.

The structure of strips produced from the Cu–1 wt % Y binary alloy using cold deformation by rolling to the degree of deformation of ~99%, followed by recrystallization annealing, as well as the process of texture formation in these strips, is studied. The possibility of forming a perfect cubic texture in a thin strip made of a binary yttrium-modified copper-based alloy has been shown in principle, which opens the prospect of the use of this alloy to produce substrates for strip high-temperature superconductors of the second generation. The optimum conditions of annealing have been determined, which make it possible to form a perfect biaxial texture in the Cu–1 wt % Y alloy with a content of cubic grains {001}〈100〉 ± 10° on the surface of the textured strip of over 95%.

A method of prediction of distributions of local electric fields in composite media based on analysis of the tensor operators of the concentration of intensity and induction is proposed. Both general expressions and the relations for calculating these operators are obtained in various approximations. The analytical expressions are presented for the operators of the concentration of electric fields in various types of inhomogeneous structures obtained in the generalized singular approximation.

Transverse eigenvibrations of a pipeline element fixed between two supports and transporting an ideal fluid are investigated. The global properties of the spectrum in dependence on the value of the transported-fluid velocity, the relative linear densities of the pipe material and the fluid, the longitudinal force, and its direction are established.

The growth in the amplitude of the small nonsphericity of cavitation bubbles in acetone and water under strong compression is considered. A hydrodynamic model is used in which the compressibility of the liquid, the nonstationary thermal conduction of the vapor and the liquid, and nonequilibrium evaporation–condensation processes, as well as imperfection of the vapor, are considered. It has been shown that the increase in the amplitude of the small nonsphericity of cavitation bubbles in the form of separate spherical harmonics during compression in water is substantially (more than 10 times) higher than during compression in acetone. This indicates that acetone is much more advantageous over water to implement a process of the nearer-to-spherical extreme compression of the medium in the cavitation bubbles.

Results of the experimental study of vibration stabilization of the process of postcritical deformation during the tensile testing of solid cylindrical specimens made of 20 and 40Cr structural steels under additional vibrations are presented. The vibrations are implemented using cyclic torsion of the specimens at a small amplitude and a frequency of 10–30 Hz.