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Data on the variability of vertical and temporal aerosol structures in the stratosphere over Tomsk received during experiments at the lidar station for high-altitude atmosphere sounding of Institute of Atmospheric Optics SB RAS carried out in 2011-2015 are described. As in the previous studies, the emphasis is placed on disturbances of the aerosol components in the stratosphere due to volcanic eruptions and on identification of peculiarities in the intra-annual variability of the stratospheric aerosol content. A feature of that period, except for the second half of 2011 (the appearance of eruptive layers from the Grimsvotn volcano eruption over Tomsk), was near absence of volcanic activity, which leads to the formation of stratospheric aerosol and its transfer toward Tomsk; this allows the study of the behavior of the vertical structure of the background aerosol in the stratosphere during the five years. The analysis of the lidar data shows a steady trend of aerosol filling of the lower stratosphere during cold seasons, with the aerosol content maximum in December-January, and near absence in warm seasons throughout the stratosphere.

The high-resolution analysis of the ro-vibrational IR spectrum of the absorption bending bands n₂ + n₄ (F₁) and n₂ + n₄ (F₂) of the ²⁸SiH₄ molecule is performed with the SPHETOM software package. About 618 experimental transitions are assigned to n₂ + n₄ (F₁) and n₂ + n₄ (F₂) bands with J^max = 8. Rotational, centrifugal distortion, tetrahedral splitting, and resonance interaction parameters for these vibrational bands are determined from the weighted fit of experimental line positions. The obtained set of parameters reproduces the initial experimental data with the accuracy closed to experimental uncertainties, d_rms = 8 × 10^-4 cm^-1.

A method for parameterizations of the absorption of UV radiation by atmospheric ozone is described. Parameterizations are proposed for computer modeling of tropospheric fluxes of UV-A and UV-B radiation and modified fluxes of biologically active UV radiation in medical applications (for the analysis of vitamin D formation and risk of erythema, cancer, and cataracts). The parameterizations allow solution of the UV radiation transfer equations at the only effective spectral point to obtain integral fluxes in the 280-400 nm range (taking into account the spectral factors characterizing biological effects). When using the parameterizations, the characteristic errors in the calculations of the fluxes in the clear and cloudy troposphere are ~ 3-5%. The use of these parameterizations is relevant for fast radiation models, for example for on-line modeling of UV radiation fluxes for medical purposes. This method can be used to improve the accuracy of radiation codes in general atmospheric circulation models, radiation-chemical models, etc.

A method of generation of electromagnetic energy and magnetic flux in a magnetic cumulation generator is proposed. The method is based on dynamic variation of the circuit coupling coefficient. This circuit is compared with other available circuits of magnetic energy generation with the help of magnetic cumulation (classical magnetic cumulation generator, generator with transformer coupling, and generator with a dynamic transformer). It is demonstrated that the proposed method allows obtaining high values of magnetic energy. The proposed circuit is found to be more effective than the known transformer circuit. Experiments on electromagnetic energy generation are performed, which demonstrate the efficiency of the proposed method.

This paper describes the results of measurement of the temperatures of gaseous and liquid reacting media, carried out by the thermocouple method with the use of a battery (copper-constantan-copper) of planar thermocouples, placed in the medium under study. It is shown that convective heat transfer lasting for 0.5-1.5 μs equalizes the temperatures of “hot” thermocouple junctions and environment. The relationship between the voltage on the thermobattery and time, which occurred in this type of heating, was determined by a pulse oscilloscope. The measured maximum voltage was used to determine the temperature of the medium. A series of experiments was carried out on measuring the temperature of water and emulsion explosive matrix, which were compressed by a shock wave, as well as the detonation products of ammonite with sodium hydrogencarbonate at various mass ratios. The estimates of heat fluxes from the detonation products to the metallic surfaces of the thermobattery contacting with them are obtained.

The group analysis method is applied to a system of integrodifferential equations corresponding to a linear thermoviscoelastic model. A recently developed approach for calculating the symmetry groups of such equations is used. The general solution of the governing equations for the system is obtained. Using subalgebras of the admissible Lie algebra, two classes of partially invariant solutions of the considered system of integrodifferential equations are studied.

The evolution of small perturbations of the kinematic and dynamic characteristics of the radial flow of a flat ring filled with a homogeneous Newtonian fluid or an ideal incompressible fluid is studied. When the flow rate is specified as a function of time, the basic motion is completely defined by the incompressibility condition regardless of the properties of the medium. For the streamfunction, we obtained a biparabolic equation with four homogeneous boundary conditions, which simulate adherence to the expanding (narrowing) walls of the ring. Upper-bound estimates of the perturbation are obtained using the method of integral relations for quadratic functionals. The case of exponential decay of initial perturbations is considered on a finite or infinite time interval. Justified The admissibility of the inviscid limit in the given problem is substantiated, and and both upper- and lower-bound estimates for this limit are obtained.

This paper derives a new system of equations for the simulation of the dynamics of long-wave perturbations on the surface of a thin horizontal layer of heavy viscous fluid moving under the action of turbulent gas flow. In the case of small Reynolds numbers of the fluid, this system of equations is used to derive an evolution equation for the value of deviation of the film thickness from the unperturbed level. Some solutions of this equation are given.

A steady boundary layer flow of a non-Newtonian Casson fluid over a power-law stretching sheet is investigated. A self-similar form of the governing equation is obtained, and numerical solutions are found for various values of the governing parameters. The solutions depend on the fluid material parameter. Dual solutions are obtained for some particular range of these parameters. The fluid velocity is found to decrease as the power-law stretching parameter  in the rheological Casson equation increases. At large values of  , the skin friction coefficient and the velocity profile across the boundary layer for the Casson fluid tend to those for the Newtonian fluid.

Electrokinetic processes in the vicinity of inhomogeneous ion-selective surfaces (electrodes, membranes, microchannels, and nanochannels) consisting of alternating conducting and non-conducting regions in the presence of normal-to-surface electric current are numerically studied. An increase in the electric current density is observed in the case of some particular alternation of conducting and nonconducting regions of the surface. The voltage-current characteristics of homogeneous and inhomogeneous electric membranes are found to be in qualitative agreement. Various physical phenomena leading to the emergence of supercritical current in homogeneous and inhomogeneous membranes are detected.