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Description of the developed prototype of a remote detector of hazardous substance vapors based on a tunable ¹³С¹⁶О₂ laser is given. Results of test measurements of laser radiation transmission of organic liquid vapors (acetone, ammonia, ethanol, gasoline) are presented. The remote detection of acetone and ammonia vapors at distances up to 100 m is experimentally implemented.

The results of two-frequency lidar investigation at wavelengths of 561 and 532 nm of the atmosphere scattering are presented. The laser radiation band covers two emission lines of atomic oxygen and three emission lines of atomic nitrogen. The lines correspond to the transitions between the exited states of ions of atomic oxygen or nitrogen. The possibility of application of the lidar method for ionosphere investigations is discussed. The physical basis of this method may be the resonance scattering on upper atmosphere ions.

The spatiotemporal variability of carbon monoxide (CO) during the atmospheric blocking event over European Russia in summer of 2010 is studied using the CO measurements from satellite Atmospheric Infrared Sounder (AIRS) instrument. Total column CO data from AIRS are compared with those from the ground-based spectrometer operated at Zvenigorod Scientific Station of A.M. Obukhov Institute of Atmospheric Physics. The peculiarities of CO field evolution conditioned by the regional atmospheric circulation associated with the omega block in the presence of severe wildfires are revealed.

A three-dimensional numerical model of moist convection and formation of convective cloudiness in the Arctic atmosphere is considered. A model of mixed clouds with explicit description of liquid and ice phases is used with nonstationary equations for cloud-drop and ice-particle size distributions. The model capability in the reproduction of polar mesoscale cyclones in the Arctic atmosphere is analyzed.

A technique is developed for retrieving the vertical profile of the mass saltation flux from measurements of the saltating sand mass concentration and wind velocity in the surface air layer. The technique is based on the solution of direct and inverse problems of the saltation sand dynamics. In order to estimate the saltating sand sliding coefficient, calculation results are compared with measurements in wind channels. The conditions for the saltating sand trajectories to fall in the altitude ranges from 0.5 to 1.0 cm and from 1.0 to 2.0 cm are ascertained. The effects of the diameter, sand grain liftoff velocity and angle, and the friction velocity on the sliding coefficient are analyzed. The sliding coefficient for sand particles of 100 μm diameter is estimated for the first time.

Transfer of the solar radiation in a freely expanding spherical atomic cloud is numerically investigated. The spectral and spatial characteristics of the absorbed and scattered radiation are calculated; the influence of the expansion velocity of the medium on them are detected.

The remote sensing results of the dynamics of thermokarst lake areas are presented. The study is carried out for 29 test sites in the permafrost zone of Western Siberia and covers 35 years. It shows a trend toward a decrease in the areas of thermokarst lakes during the period under study. The time series of climatic variables (temperature and precipitation), received from reanalysis, are analyzed. It is found that an increase in the annual average temperature is accompanied by a reduction in the areas of thermokarst lakes located in the permafrost zone of Western Siberia.

Air environment pulse-periodic discharge in apokamp mode is studied. It is confirmed that the blue and red diffuse minijets (apokamps) form from the plasma discharge channel under the floating potential. It is shown that at low pressures the apokamps are units-tens of centimeters in size and possess the properties inherent to giant plasma jets (sprites, starters, and blue jets) observed in the Earth's atmosphere at altitudes of 17-100 km. Morphological, spectral, and electrophysical parameters of apokamps in various conditions are ascertained. It is found that plasma minijets are easier implementable at the positive polarity of the discharge channel. A gradual change in the color of diffuse jets with a decrease in the air pressure is demonstrated.

The results of experimental study of a gas-discharge Ne-Eu laser are presented. In this work, lasing lines, pulse shapes in europium atom and ion in the conditions of this experiment are identified. Influence of the buffer gas pressure and pulse repetition rate on the energy characteristics of the laser is ascertained; their optimal values are determined. It is shown that under optimum operating conditions for the corresponding transitions the output power is 1 W at 1759 nm line and 70 mW at 664.5 nm line.

This paper deals with the use of a scalar product with derivatives for constructing semi-orthogonal spline-wavelets. The reduction of supports of such wavelets in comparison with classical semi-orthogonal wavelets is shown. For the splines of the 3rd degree, the algorithm of wavelet-transformation in the form of the solution to a three-diagonal system of the linear equations with strict diagonal prevalence has been obtained. The results of numerical experiments on the calculation of derivatives of a discretely set function are presented.