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The paper presents the results of dust load spatial distribution at Omsk city territory by the results of snow survey in 2013. The districts with low, middle, high, and very high pollution levels were revealed at the territory of the city. The most polluted districts are located at the territory of the east part of Omsk, where the biggest enterprises are located. The obtained data were compared with the dust data for other cities of the south part of the Western Siberia.

In the present work, peculiarities of the design and main characteristics of a series of airborne lidars developed at the Institute of Atmospheric Optics SB RAS are given. Physicotechnical parametres of lidars intended for sensing optically dense media, such as cloudiness, atmospheric pollution, and sea water are considered.

The description of the laser rangefinder monitoring system for Ust–Kamenogorsk shipping lock's wall deflections and the results of 8.5–years observations are presented. Ust–Kamenogorsk shipping lock has high-head single-lift chamber with 47 m depth. The wall deflections are caused by seasonal thermal deformations and dynamic loads related to the lock filling-emptying. The trend is found of the chamber width decrease with the rate of ~ 2.2 mm/year in the upper part of the lock. The effect of the lock filling-emptying process on the wall deflection dynamics was studied.

The results of experiments filamentation of terawatt femtosecond pulses of a Ti:Sapphire laser at atmospheric path length of 106 m using different spatial focus and power pulses are presented. The high efficiency control for the position and length of the field filamentation change the initial focus of the laser beam. The dependences of the length and position of filamentation on the initial degree of focus and power of the pulses, the number of filaments along the filamentation region are found. The obtained data on the length of the filamentation regionand the number of filaments with the results of earlier experiments and data of other authors were compared.

The paper presents the study of the 557.7 and 630–nm atomic oxygen emission responses to sharp variations in solar wind parameters, caused by shocks. The optical and geomagnetic data of the Eastern Siberia and interplanetary magnetic field and solar wind data were used for the analysis. It has been found that the considered emission intensity was increased for some cases, whereas in other cases there were no responses during sudden sharp variations in solar wind plasma speed and density. It has been shown that the presence or absence of the responses in the emissions was not related to the disturbance amplitude of the solar wind parameters. It has been suggested that the emission intensity increase could be caused by the electrons precipitation from the magnetic trap during interaction between the solar wind shock and magnetosphere.

The structure and spin moments of iron-silicon clusters FeSi _n are calculated by a multiconfigurational self-consistent field (MCSCF) method in order to refine the spin moments in the ground state and their changes during the transition from the ground electronic state to excited ones. Transition energies to the first singlet state are obtained for the first time; the degree of stability of magnetic properties with temperature is evaluated in a wide range. The limiting number of silicon atoms, which corresponds to the disappearance of the cluster magnetic moment is found. The non-empirical calculation is compared with the data of the elecron density functional method in its different variants. The presence of iron-silicon clusters in the substance can be the reason for a local alteration of the magnetic field.

Molecules of phosphoryl compounds (H ₃PO, HF ₂PO, F ₃PO, Cl ₃PO, CH ₃POF ₂, CH ₃POCl ₂, and (CH ₃) ₃PO) are calculated at the Hartree-Fock, density functional theory with the B3LYP functional, and Möller-Plesset second order perturbation theory levels with different basis sets. Based on the calculation results and the comparison with the existing experimental data, methods and basis sets providing the calculation of the structures, dipole moments, and polarizabilities of phosphoryl compounds with high accuracy and low costs of computational resources are selected.

Within the quantum theory of atoms in molecules (QTAIM) the electronic structure of sulphoxylate acid НОSОH and compounds of a homological series of ethers of sulphoxylate acid CH ₃(CH ₂) _n ОSОH, where n ≤ 8, is studied. It is found that there is an intramolecular hydrogen bond O⋯H resulting in the formation of a cyclic structure СH ₃CH ₂OSOH. Qualitative relationships of the electronegativities of the groups χ( R) are obtained and the χ( R) scale is derived. The possibilities of predicting “structure-property” correlations are discussed.

We report for the first time the synthesis of γ-iminophosphonates and phosphine oxides from the acid-catalysed reaction of primary amines with γ-phosphonylketones. The full characterization of these compounds through their ¹H, ³¹P, and ¹³C NMR spectra indicates that they are obtained as a mixture of Z and E isomers. An unambiguous method for the assignment of these configurations, based on the ¹³C chemical shifts of C2 carbon atoms in the a position with respect to the C=N double bond is used. The ³¹P chemical shifts are also of diagnostic importance in assigning the Z and E configurations. Indeed, the phosphorus atom is found to resonate at a slightly higher field in Z isomers.

Two ligands for coordination compounds incorporating benzimidazole moieties, namely 1,1'-butane-1,4-diylbis(5,6-dimethyl-1H-benzimidazole) and 1,1'-butane-1,4-diylbis(1H-benzimidazole), are synthesized and then characterized both experimentally and theoretically. Their structures are studied by single crystal X-ray diffraction, UV-Vis spectroscopy, and FT-IR spectroscopy. The optimized geometries, vibrational frequencies, vertical excitation energies of the two ligands are calculated using the (TD)DFT/B3LYP/TZVP method. The calculated results reproduce the experimental data. Additional bonding information about the coordinated N atoms in the two ligands is obtained by FMO and NBO analysis to investigate the substitute-group effect on the coordination ability. The results confirm that the ligand with electron-donating methyl groups on the benzimidazole moieties has a stronger coordination ability.