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We have developed and experimentally implemented an adaptive laser vector-phase hydroacoustic measuring system, which allows one to determine the total acoustic intensity vector. A receiving element of the measuring system comprises six spatially separated fibre-optic coil-type sensors. Signals from the sensors are phase demodulated by using a six-channel adaptive holographic interferometer based on dynamic holograms multiplexed in a photorefractive CdTe crystal. Performance of the developed measuring system has been experimentally tested by determining the bearing and localisation of a source of a weak hydroacoustic field.

The effect of shape deformation of a spherical nano-object on quantum states of a particle in it has been analyzed theoretically. For this purpose, a functional method of surface shape perturbation theory has been proposed. The method allows us to determine the effect of a wide range of deviations of a limited three-dimensional volume (nano-object) from the initial shape on the quantum characteristics of a charge localized inside the nano-object. An analysis has demonstrated that the probability density for a particle in quantum-size states is more sensitive to surface shape perturbations than the energy spectrum and the density of quantum states. Even small shape perturbations lead to a smearing of the probability density for the location of a particle inside a nano-object and lift the degeneracy in the magnetic quantum number. A mixing of pure states corresponding to a sphere has been observed. The degree of mixing and the splitting of the energy levels increase with increasing quantum numbers land m.

We present the results of studying the nonlinear optical response of nanodispersions of semiconductor (TiO2, ZnO) and dielectric (SiO2, Al2O3) nanoparticles of spherical, spheroidal and flake shape, suspended in polar and nonpolar dielectric matrices (water, isopropanol, polymethylsiloxane and transformer oil) by means of z-scanning in the field of low-intensity visible laser radiation. It is found that, unlike semiconductor nanoparticles and particles of spherical shape, flake-shaped SiO2 and Al2O3 nanoparticles suspended in nonpolar matrices exhibit nonlinear optical response within the intensity interval from 0 to 500 W cm-2 that vanishes at higher intensities. The diagrams of energy states of the optical electrons in nanoparticles that allow explanation of differences in the nonlinear-optical properties of nanodispersions are proposed. Good agreement between the experimental and theoretical dependences of nonlinear refractive indices and absorption coefficients on the intensity of radiation is observed.

The problem on the interaction between a spherical body that oscillates in a prescribed manner and a thin elastic cylindrical shell filled with an ideal compressible liquid is formulated. It is assumed that the geometrical center of the sphere is located on the cylinder axis. The problem is solved based on the possibility of representing a partial solution of the Helmholtz equation written in cylindrical coordinates in terms of partial solutions in spherical coordinates, and vice versa. By satisfying the boundary conditions on the surfaces of the sphere and the shell, we obtain an infinite system of linear algebraic equations to determine the coefficients of expansion of the liquid-velocity potential into a Fourier series in terms of Legendre polynomials. The hydrodynamic characteristics of the liquid filling the cylindrical shell are determined and compared with the cases where a sphere oscillates in an infinite liquid and in a rigid cylindrical vessel

A problem on the interaction of a spherical body oscillating in a predetermined fashion and a rigid cylinder is formulated. The bodies do not intersect, are immersed into an ideal compressible liquid, and their centers are in one plane. The solution is based on the possibility of representing the partial solution of the Helmholtz equation, written in cylindrical coordinates, in terms of partial solutions in spherical coordinates, and vice versa. An infinite system of linear algebraic equations is obtained by satisfying the boundary conditions on the sphere and cylinder surfaces. The system is intended for determining the coefficients of the expansion of the velocity potential into a series in terms of spherical and trigonometric functions. The system obtained is solved by the reduction method. The appropriateness of this method is substantiated. The hydrodynamic characteristics of the liquid surrounding the spherical and cylindrical bodies are determined. A comparison is made with the problem on a sphere oscillating in an infinite incompressible liquid that contains also a cylinder and in a compressible liquid that contains nothing more. Two types of motion of the sphere — pulsation and oscillation — are considered

The problem on the interaction between a spherical body oscillating by a definite law and a rigid cylinder filled with an ideal compressible liquid is formulated. The geometrical center of the sphere is located on the cylinder axis. The solution is based on the possibility of representing the particular solutions of the Helmholtz equation in cylindrical coordinates in terms of particular solutions in spherical coordinates, and vice versa. As a result of satisfaction of the boundary conditions on the surfaces of the sphere and cylinder, an infinite system of linear algebraic equations is obtained to determine the coefficients of expansion of the potential of liquid velocities into a Fourier series in terms of Legendre polynomials. The use of the reduction technique for solving the infinite system obtained is substantiated. The hydrodynamic characteristics of the liquid filling the cylindrical cavity are determined and compared with the case of a sphere vibrating in an infinite liquid.

Abstract: The structure of CuII complexes with hydroxamic acids Cu[R1N(O)−(O)CR2]2, where R1=Ph, R2=Me; R1=Me, R2=Ph, was studied by ESR spectroscopy. In toluene solutions and low-temperature glasses, the complexes exist as two forms, which were identified ascis-andtrans-isomers. The proportions of the isomers were determined.

Conclusions 1.Equations for entropy production were derived from a position of irreversible thermodynamic processes taking account of irreversibility associated with temperature gradients, physicochemical transformations, and damage which accumulates in the material due to mechanical loads.2.By using the kinetic equation obtained for damage accumulation an estimate is given for entropy arising in the material with programmed mechanical loading.

A method of calculating higher-order correlation corrections, using Green's functions and the Feynman diagrammatic technique, is developed. A basis of the single-electron orbitals is computed using the relativistic Hartree-Fock method. The interaction of an atom with an external field is computed by solving the time-dependent Hartree-Fock equations. In the methodology presented, we consider all the second-order correlation corrections and the dominating classes of higher order diagrams: the screening of the Coulomb interaction of electrons, particle-hole interaction and mass operator iterations. The calculation of the energy levels, the intervals of hyperfine structure and the amplitudes of the allowed EI-transitions in Cs shows that the method developed ensures precision at the 0.1–1% level. A calculation of the parity nonconservation of the El-amplitude of the transition 6s–7s in Cs is produced. The result <6s¦Dz¦7s> = -(0.91 ± 0.01)·10-11 i¦e¦aB (-QW/N) is obtained.

A machine for tension, compression, and bend testing of carbon-carbon composite materials at temperatures up to 3300 K in vacuum, air, and an inert atmosphere is described. Mechanical design solutions providing a uniform temperature field in the volume of the specimen, methods of measurement of strain and temperature with increased accuracy, and a plan of automation of the experiment are given.

1.It was demonstrated that shells of the investigated materials in the temperature interval 20–500 °C fail either in consequence of exhaustion of strength or as a result of loss of stability. At room temperature exhaustion of strength occurs; upon heating there is gradual transition to loss of stability. The replacement of the mechanism of rupture is due to decrease in strength of the bond upon heating, which leads to lessening of the bond between the reinforcing layers.2.The suggested analytical dependences make it possible to evaluate the limit state and also the type of rupture of cylindrical shells of reinforced materials under conditions of nonuniform heating and axial compression.

Conclusions 1.If there is reliable adhesion between the skins and the filling, one obtains the highest carrying capacity on loading at normal and elevated temperatures.2.The form of loading affects the carrying capacity at room temperature. For instance, if external hydrostatic pressure is accompanied by axial force, the carrying capacity is reduced by about 30% by comparison with the value for hydrostatic pressure alone. The effects of the detailed form of loading become somewhat less as the temperature is raised.3.The main factor affecting the carrying capacity of a multilayer conical shell at elevated temperatures is the loss of adhesion between layers.4.The carrying capacity of a conical shell falls considerably when both sides are heated to 70°C, or when one side is heated to 150°C (the fall is 50–70% relative to the same conditions at 20°C.

Abstract We studied the effects of 30-day injections of sulpyride and treatment with Prostatilen on the development of prostatic hyperplasia and LPO in rats. Sulpyride induced proliferation of lateral lobes, increased the content of lipid hydroperoxides and glutathione peroxidase activity in the gland; in the blood this preparation increased lipid hydroperoxide concentration and decreased glutathione peroxidase and total antioxidant activity. Prostatilen prevented the development of hyperplasia and normalized the prooxidant-antioxidant balance in tissues, except total antioxidant activity of the blood.

We studied the effect of transplantation of fetal liver cells and postnuclear cytoplasmic fraction from human fetal soft tissues on the prooxidant-antioxidant equilibrium in the liver and blood of rats after partial hepatectomy. The preparations increased antioxidant activity and decreased the intensity of lipid peroxidation, which probably contributes to their therapeutic effects.

This article describes an apparatus for determining the load-carrying capacity of reinforced plastics in various media under short-time loads.

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The nonlinear-optical properties of heterogeneous liquid nanophase composites based on high-energy-gap Al2O3nanoparticles are studied experimentally. The factors determining the nonlinear-optical properties of composites and their strong dependence on the matrix material are analysed and physical mechanisms are proposed to explain the results obtained.