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The study examines changes in the abundance (density) and distribution of European Sprattus sprattus (Linnaeus, 1758) eggs and larvae, as well as the phenology of its spawning depending on hydrologic factors and abundance of gelatinous macroplankton in the Black Sea in November 2016–2017. An increase in temperature of the sea surface layer observed since the beginning of the century and the enhanced heat content of the cold intermediate layer contributed to the preservation of warm-water mesozooplankton at the end of the fall hydrologic season, which provided favorable trophic conditions for all planktophages. The biomass of scyphomedusa Aurelia aurita was the third largest in the gelatinous macroplankton in 2016 and the largest in 2017 for the long-term annual research in fall months. Gelatinous macroplankton, however, did not have a significant impact on the survival of sprat in the early stages of its development. The average number of sprat eggs and larvae in November 2016 (184 and 11 ind/m2, respectively) and November 2017 (268 and 21 ind/m2, respectively) exceeded their maximum values recorded in the 1950s. The larvae did not differ in length composition in the beginning of the spawning season in 2016 and 2017.

—The bay waters of the Sea of Okhotsk near the Shantar Islands are the most important summer grazing areas for bowhead whales (Balaena mysticetus) of the Okhotsk population. A hydrobiological survey during the period from July 12–28th, 2016, demonstrated that waters around the Shantar archipelago are characterized by high concentrations of humic substance supplied by the peat-laden banks of rivers flowing into the bays. The average chlorophyll concentrations in bottom waters of Uda and Academy bays were 1.1 and 4.3 mg/m3, respectively. Uda and Academy bays are mainly considered heterotrophic and autotrophic basins, respectively. The measured zooplankton biomass in Uda Bay ranged from 9.5 to 2513 mg/m3, averaging 736 mg/m3; the corresponding characteristics in Academy Bay were 0.38 to 3620 mg/m3, averaging 458 mg/m3. In the Shantar water area, copepods of the species Calanus glacialis were the dominant contributor in terms of zooplankton biomass and species abundance. During early summer, nine bowhead whales were sighted south off Feklistov Island and lone whales were recorded in the North Strait and at the mouth of Nikolai Bay. The low density of polar whales in the Shantar water area in early summer may be due to the low zooplankton biomass after spring bloom and the last spawning.

The modern pattern of distribution and feeding habits of the bowhead whale, Balaena mysticetus, in the Sea of Okhotsk are studied. The existence of a feeding aggregation of this whale species in the southwesternmost portion (apex) of Ulban Bay has been confirmed. There, the animals feed in shallow waters with depths of 3–5 m, which are only slightly larger than their body height. The quantitative composition and species structure of zooplankton at the stations that were set near feeding whales have been analyzed. In the samples taken in the immediate proximity to the feeding whales, the abundance of zooplankton reached 31409 ind./m3, with the average value of 17565 ind./m3. The lowest abundance, from 56 to 1879 ind./m3 (mean 927 ind./m3), was in the samples from western Konstantin Bay, where bowhead whales were not observed. In 16 samples collected in the immediate proximity to the feeding whales in the shallow waters of Ulban Bay, the average zooplankton biomass was 547.9 mg/m3, which is 3.9 times higher than that in the samples from waters where the whales were absent. Copepods dominated quantitatively at all the stations in Akademiya Bay. The proportion of euphausiids in the zooplankton biomass was lower than 1%, both near the feeding whales and in the absence of whales.

Stages of work are listed in monitoring corrosion behavior by control specimens, methods are considered for evaluating material corrosion resistance, and types of control specimens used in monitoring equipment and pipelines are presented.

An axisymmetric thermoelastic problem for a sphere with conical cuts in the poles under the action of a quasi-stationary temperature field depending on the meridional angle and on the sphere radius is solved by a method based on the Castigliano variational principle. Orthonormalized systems of polynomials are used as the coordinate functions. Results of numerical calculations of the stress state of a spherical solid are presented.

This paper presents a solution of the problem of unsteady heat transfer in a three-layer hollow sphere in a central-symmetric formulation with various time-dependent boundary conditions on the inner and outer surfaces. In each layer of the sphere there is heat release of known intensity which depends on the radial coordinate and time. The solution is obtained by a finite integral transform on the radial coordinate. A numerical solution is presented for one version of the boundary conditions.

Two new hybrid compounds, which belong to autocomplexes of the dinitroquinoline series and contain an NH spacer and fragments of photochromic fulgimides as donor components, were synthesized. These autocomplexes were used as ligands in the synthesis of cobalt-containing metal chelates. The spectral-kinetic study revealed that these compounds exhibit photochromism. The introduction of photochromic fulgimide moieties into the autocomplexes has no substantial effect on the spectral properties of the latter but influences the kinetics of photochromic transformations by decreasing their efficiency. Chelate complexes of the hybrid compounds with cobalt ions are characterized by the lowest efficiency of photochromic transformations due to a decrease in the intensity of activating radiation as a result of its absorption by the dinitroquinoline moieties, which are not conjugated with fragments of photochromic compounds.

A number of new chelate compounds based on 3d-transition metals and autocomplexes of the dinitroquinoline series were synthesized. The crystalline structure of the new complexes was determined by X-ray analysis, and their spectral properties were studied. The complexes have a conformation which gives rise to two modes of contact intramolecular charge transfer: intraligand, which is intrinsic to the initial ligand molecules, and interligand (as in binary charge-transfer complexes). The latter involves the corresponding pairs of donor and acceptor fragments of the initial ligand molecules, which appear spatially close as a result of complex formation.

An integral transformation with the aid of which a solution of the problem of unsteady-state heat transfer in a system of three coaxial finite cylinders with different boundary conditions on their surfaces depending on space and time is presented. Each of the cylinders evolves heat of a certain intensity, depending on time and coordinates. A numerical solution of one variant of the boundary conditions is given and illustrated by figures. The method of transforming the solution of the problem with other boundary conditions is shown.

A number of new NH-bridged nitroquinoline derivatives with intramolecular charge transfer (autocomplexes) were synthesized starting from 8-chloro-5,7-dinitroquinoline and aromatic N,O-heterocyclic amines characterized by different donor powers and substitution patterns. The charge transfer in their molecules may occur via both direct polar conjugation through the bond sequence including the bridging nitrogen atom and through space between spatially close molecular fragments (contact charge transfer).

Procedures for synthesis of coordination compounds of copper(II) with bis(5-amino-1,2,4-triazol-3-yl)alkanes as ligands. A conclusion was drawn that the coordination polyhedron of copper(II) has different configurations depending on the structure of the ligand and on the coordination mode.

Results of cholecystectomy performance were analyzed in 99 patients with a biliary calculous disease, the course of which have become complicated by cholecystitis occurrence, in 49 of them professional diseases of respiratory organs, including silicosis, antracosis, were registered. Estimating results of laparoscopic and open cholecystectomy, we have established, that carboperitoneum in laparoscopic cholecystectomy impacts negatively the course of early postoperative period, what manifests with hemodynamic and respiratory disorders. The level of fibronectin and endotelin--1 in the blood plasm directly depends on the respiratory disorders severity and may be applied as a test for respiratory dysfunction. The method of cholecystectomy in patients, suffering professional diseases of respiratory organs, must be selected, depending on severity of functional disorders of respiratory organs.

Possible pathways of alkylation of 5-aminotetrazole with dihalo-substituted compounds and the alkylation products were studied.

A scheme of acylation of amino-1,2,4-triazoles under conditions of low-temperature polycondensation is proposed. The effect of reaction conditions on the yield and properties of reaction products is established.

The frequencies and forms of the normal vibrations of 5-trifluoromethyl- and 1- methyl-5-nitrotetrazole and the potential energy constants were calculated, and the effect of electron-acceptor substituents on the electronic structure of the tetrazole ring was investigated. The position of the hydrogen atom for 5-trifluoromethyltetrazole was established by the methods of vibrational spectroscopy. The frequencies in the experimental spectra were assigned to the principal types of normal vibrations.

The frequencies and forms of the normal vibrations of 3-azido- and 3-azido-5-methyl-1,2,4-triazoles and their 1-deutero-substituted derivatives were calculated, the effect of the geometrical parameters of 3-azido-1,2,4-triazole on the vibrational spectra was investigated, and the most probable three-dimensional model of the molecule was selected. The solution of the inverse spectral problem was effected by the method of least squares, and the potential energy constants of the azidotriazoles were calculated. It is shown that the force constants of the azido group increase and the elastic constants of the ring decrease when an azido group is introduced into the 1,2,4-triazole molecule. The frequencies in the experimental spectra were assigned to the principal types of normal vibrations.

Bands of the sequence &V = --2, --3, --4 of the second positive system of nitrogen N~(2+) were used in the capacity of the pyrometric component when studying glow discharge in sealed or weakly permeable tubes [6, 7]. The present work examines the usefulness of MURS for operational monitoring of the gas temperature in a glow discharge in an atmosphere of nitrogen with a pumping rate v through an interelectrode gap of ~i00 m/sec at an operating pressure of p > 1.33 kPa. The need for similar studies is caused by lasers being used in technology which have separate excitation of the gain medium's components [8] along with closed cycle CO2-EDL's. The merit of identifying the rotational temperature Tro t with the gas temperature Tg follows from the relationship between the rotational relaxation time TR-T [9-11] and the lifetime ~c of the C3Eu of nitrogen allowing for its deactivation due to collisions with other molecules [12]. For p = 1.33 kPa in correspondence with the data of [9-12], Tc/TR_T - i0, i.e., in the course of rc = 40 nsec rotational--translational relaxation does not take place and a Boltzmann distribution of the molecules is established in the CSHu state with respect to the rotational levels with a temperature Tro t = Tg. The validity of the proposition just made is demonstrated experimentally in [13].

From an analysis of the IR and Raman spectra and a calculation of the frequencies and forms of the normal vibrations of the nitrotriazoles, conclusions have been drawn on the structure of 3,5-dinitro-1,2,4-triazole and 1-methyl-3,5-dinitro-1,2,4-triazole. The nitro group in position 3 of the triazole ring is located in the plane of the molecule, and that in position 5 is rotated about the CN bond. The spatial nonequivalence of the nitro groups leads to the splitting of the absorption bands in the IR spectra that are characteristic for the anti- and synphase vibrations of the nitro groups.

The frequencies and forms of the normal vibrations of a number of azido derivatives of 1,2,4-triazole [3-bromo-5-azido-(I), 1-methyl-3razido-(II), and 3-azido-5-nitro-1,2,4-triazole (III)] were calculated. The inverse spectral problem for the parameters of the azido group was solved by the method of least squares. A similar method was used to calculate the potential energy constants of the triazole ring with the aid of data on the force fields of the previously investigated nitrotriazoles. It is shown that the introduction of electron-donor or electron-acceptor substituents in the triazole ring does not affect the force constants of the CN and NN bonds of the azido group. Transmission of the electronic effects in the ring as a function of the nature and position of the substituent was investigated.

The dipole moments of indazole and a number of its nitro derivatives in dioxane solution were measured. The directions of the vectors of the dipole moments of indazole in the tautomeric 1-H and 2-H forms were determined to solve the problems associated with the tautomerism and the position of the substituents in the molecules. The experimental values of the dipole moments, of the investigated compounds were compared with the values calculated via a vector additive scheme. As a result it was shown that the mononitro and dinitro derivatives of indazole exist primarily in the 1-H tautomeric form, whereas the trinitro and tetranitroindazoles exist in the 2-H tautomeric form. The ratios of the isomers were calculated for compounds that have dipole moments intermediate between the 1-H and 2-H forms. A deviation between the experimental and calculated dipole moments of compounds containing two nitro groups in the ortho position was established; this may be explained by disruption of the coplanarity of the molecules or by deviation from additivity because of the introduction of strong electron-acceptor substituents.

Standard xenon flash tubes have been tested at high powers. Results are given on the shock wave in the discharge and the spectrum at 3000–9000 a as functions of circuit parameters. It is found that the shock wave ceases to have any marked effect on envelope breakage if the circuit contains inductance. The emission is not of blackbody type in the region examined.