The results of the study of the elemental and charge composition of the plasma of a vacuum arc discharge with a cathode made of magnesium Mg are presented. Time-of-flight spectrometry was used to determine the mass-charge composition of the ion current extracted from the vacuum arc plasma. The spectral characteristics of the discharge plasma were studied by recording the power density distribution of its radiation in the optical spectral range. Both methods were used simultaneously, so that a high level of identity was maintained not only in the operating conditions of the vacuum arc, but also in the true composition of the plasma of the cathode spots, which are the elementary cells of the structure of such a discharge. It was found that the fractions of heavy charged particles, represented by single- (Mg+) and double-charged (Mg2+) magnesium ions, in the beam extracted from the expanding plasma, depend significantly on the average energy deposited in the discharge. With the increase of the average energy the fraction of Mg2+ decreased, while that of Mg+ increased. In turn, the relative amplitudes of the lines of ions (Mg II and Mg III) and atoms (Mg I) of magnesium in the emission spectra of the plasma of cathode spots did not depend on the discharge energy characteristics. Based on the obtained results, reasoning is given about the mutual complementarity of the methods used and the further development of methods for diagnostics of cathode arc plasma.

This paper presents the results of an experimental study of laser generation based on electron transitions in neutral krypton atoms in the near- and mid-infrared spectral regions, pumped by a pulsed inductive longitudinal discharge of a low-pressure gas active medium. Particular attention is given to the investigation of population inversion formation conditions and experimental studies of the influence of gas mixture compositions (Kr–Ar, Kr–He, Kr–He–Ar), gas pressure, and discharge parameters on the energy, temporal, and spatial characteristics of the laser generation. For the first time, laser generation at a wavelength of 810 nm (corresponding to the 5p → 5s transition of Kr I) was recorded in a pulsed inductive longitudinal discharge at an optimal pressure of approximately 0.05 torr. Laser generation on 4d → 5p and 6s → 5p transitions (at 1442, 1476, and 2524 nm) was also detected in pure krypton at pressures around 1 torr. Temporal lasing characteristics were investigated, showing that the optical pulse duration was 6 ± 1 ns (FWHM). The spatial beam profile had an elliptical shape with dimensions of approximately 6 ± 0.2 × 5.2 ± 0.2 mm. The pulse lasing energy did not exceed 3 μJ, corresponding to a peak power of about 600 W.

Abstract The results of aerosol condensation activity obtained at the Siberian ZOTTO background station (60.8° N, 89.35° E) are presented. The measurements were carried out during the growing season from June 18 to July 6, 2021. The condensation activity of aerosol particles was estimated from cloud activation spectra measured depending on the supersaturation of water vapor and the aerosol particles size. Based on these data, the size distributions of activated particles, the critical diameters of cloud activation, and the hygroscopicity parameter of aerosol particles are calculated. The obtained cloud activation parameters are compared with similar data obtained at background stations in the Amazon rainforest and boreal forests of Northern Europe.

One approach to constructing terahertz radiation sources for analyzing atmospheric gas composition is based on the use of nonlinear optical generators that convert the frequencies of intense near-infrared laser sources. This method’s downside is that its efficiency is proportional to the square of the generated frequency. This paper proposes a solution based on the use of cascade conversion, which involves generating intermediate frequencies in a local infrared transparency window of a nonlinear crystal and then downconverting these frequencies to the subterahertz region. For the first stage, an enhanced conversion due to a significant increase in quadratic susceptibility near optical phonons or stimulated polariton scattering is allowed. A second-stage model is considered for the process of subterahertz difference frequency generation under pumping in the local infrared transparency window in a KTP crystal. The fulfillment of collinear phase matching is demonstrated, and the figure of merit is estimated.

The morphology and composition of aerosol particles determine their activity in atmospheric heterogeneous processes and affect the radiation and chemical properties of the atmosphere. However, there is still insufficient information about the morphological characteristics of atmospheric aerosols. This work studies mineral composition of dust aerosol particles and identify natural and anthropogenic components in aerosol composition in the surface air layer in Moscow metropolis in winter. Microparticles containing a lot of potentially toxic elements, such as heavy metals and metalloids of anthropogenic or mixed origin, were found. Several groups of metal-containing microparticles in near-surface aerosols were identified, the most common of which were: (1) sulfates (mainly Ba and Sr); (2) sulfides (Fe, Sb, and Pb); (3) oxides (Fe, W, Cu, As, Cd, and Pb); (4) intermetallides (Pb–Sn–Zn, Pb–Zn, Cu–Zn, Cu–Pb, Te–Sb–Al–Bi, and Fe–Ni–Cu–Sn–Fe–Cr–Ni); (5) native metals (Pb, Zn, Ni, Te, Fe, Zr, and W). The distributions of different elements over the surface of a filter with an aerosol sample was estimated. It was found that most of microminerals in dust particles were in the calcium phase, and to a lesser extent, in silicate and aluminosilicate phases. The results complement information on the morphology and micro-mineral composition of aerosols in the near-surface air of a megalopolis and can be useful both for clarifying the role of aerosol particles in atmospheric heterogenic processes which change the climate and for solving applied environmental problems.

The Russian Federation regularly participates in the international program of the Acid Deposition Monitoring Network in East Asia (EANET). Two regions in the Asian Russia were selected for monitoring research: South-Eastern Siberia (three sites) and Far East (one site). A database on the chemical composition of atmospheric aerosol has been compiled over the operation period. The spatial and temporal variability of the ion composition of aerosol over five-year periods from 2001 to 2024 was studied using the ratio of the summed concentrations of the main ions. Based on data from other projects, some relevant trace elements in atmospheric aerosol were analyzed: Li, Al, Ti, V, Mn, Fe, Sr, Th, U, Ba, and Co (of terrigenous origin) and Cr, Cu, and Ni (of nonterrigenous origin). Their contribution to the total level of atmospheric air pollution at the EANET monitoring sites was assessed. The monitoring results on atmospheric depositions can be used for practical assessment of the environmental conditions, scientific research, and public information.

In 2023, more than a third of dangerous weather events in the Siberian Federal District were associated with strong wind, which emphasizes the importance of improving the accuracy and timing of its forecasting. Modern numerical simulation and machine learning methods make it possible to improve forecasts; however, the task of direct calculation of wind gusts remains topical due to the limited resolution of models. An original method is proposed for correcting the results of short-term forecast of wind gusts obtained on the basis of mesoscale models of numerical weather forecasting using advance measurements and artificial neural networks. The results show that the proposed correction method makes it possible to improve the forecast of wind gusts by various semiempirical methods. The results can be applied in meteorology, energy engineering, transportation, and other industries to minimize damage from dangerous weather events.

The prediction of the level of air pollution by gaseous and aerosol constituents in cities becomes increasingly significant in view of their serious negative impact on public health and growing ecological risks. The article presents an approach to estimating and adjusting the emission power of anthropogenic sources based on direct and inverse modeling. The WRF-Chem model was used as a direct simulation tool, and the IMDAF system developed by the authors was used for inverse simulation. The results of direct simulation provided data on meteorological fields and the distribution of admixtures necessary for solving adjoint problems. The use of the adjoint problem method made it possible to calculate a correction factor that determines how much the power of sources that fall into the sensitivity zone should be changed to achieve the best agreement with measurements. Our approach can be used to improve the prediction of air quality, refine the inventories of anthropogenic emissions, and develop the strategies for reducing the ecological risks on global and regional scales.