Vol 489, No 6 (2019)

Mathematics
On the Gardner Problem for the Phase-Locked Loops
Kuznetsov N.V., Lobachev M.Y., Yuldashev M.V., Yuldashev R.V.
Abstract

This report shows the possibilities of solving the Gardner problem of determining the lock-in range for multidimensional phase-locked loops systems. The development of analogs of classical stability criteria for the cylindrical phase space made it possible to obtain analytical estimates of the lock-in range for third-order system.

Доклады Академии наук. 2019;489(6):541-544
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Crystallization of Binary Alloys and Non-Equilibrium Phase Transitions
Radkevich E.V., Vasil’eva O.A., Sidorov M.I.
Abstract

A model was constructed for the reconstruction of the initial stage of crystallization of binary alloys as a nonequilibrium phase transition, the mechanism of which is diffusion stratification. Numerical experiments were performed. Self-excitation of a homogeneous state by the edge control melt cooling condition.

Доклады Академии наук. 2019;489(6):545-551
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Kinetic algorithms for the modeling of conductive fluids flow on high performance computational systems
Chetverushkin B.N., Saveliev A.V., Saveliev V.I.
Abstract

This letter presents the results of the mathematical modeling of processes of electrically conducting fluid flow dynamics for complex heat transfer systems. The study was carried out based on detailed calculations on parallel high performance computational systems on the basis of the kinetically consistent magnetogasdynamic approach, adjusted for this class of problems. The kinetically consistent algorithm adapts well to the architecture of high performance computational systems with massive parallelism and makes it possible to conduct effective research of complex heat transfer systems with high resolution. The article presents the approach, method and algorithms as well as the results of the mathematical modeling.

Доклады Академии наук. 2019;489(6):552-557
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Computer Engineering
The duality principle and new forms of the inverse Laplace transform for the analysis of signal propagation in inhomogeneous media with dispersion
Pavelyev A.G., Pavelyev A.A.
Abstract

New equations for Laplace transform inversion are obtained. The equations satisfy the causality principle. The impulse response of a channel is determined in order to analyze dispersion distortions in inhomogeneous media. The impulse response excludes the possibility that the signal exceeds the speed of light in the medium. The transmission bandwidth, the angular spectrum, and the Doppler shift in the ionosphere are computed.

Доклады Академии наук. 2019;489(6):558-563
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Technical Physics
Effect of standing waves on the local strength of modeled ice field
Epifanov V.P., Sazonov K.E.
Abstract

Two scenarios of the influence of standing waves on the strength properties of ice lying on the surface of the liquid are considered: in the process of freezing the ice field and as a result of instability, which is caused by compression on the pool walls due to the expansion of water during freezing. The obtained experimental hardness profiles of the ice field indicate the formation of periodic structures characteristic of the wave process. It is shown that in both cases the standing waves arising in the basin change the strength characteristics of the ice cover.

Доклады Академии наук. 2019;489(6):564-569
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Mechanics
The precession of Mercury’s orbit
Amel’kin N.I.
Abstract

Within the framework of classical mechanics the influence of the planets in the solar system to the precession of the orbit of Mercury is investigated. It is shown that the average offset of the perihelion of mercury’s orbit computed within the flat limited tasks is 556,5 angular seconds per century and coincides with the observation data with relative accuracy of 2,5%. Incomplete overlap between the computed average offset and observations can be explained by the presence in observations offset oscillatory components with a total amplitude up to 20 angular seconds and periods from several years to several decades.

Доклады Академии наук. 2019;489(6):570-575
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Criteria of existence of Ferry vortex singularities in supersonic conical flows in the absence of branch points of shock waves
Zubin M.A., Maksimov F.A., Ostapenko N.A.
Abstract

Based on the results of a numerical study of the control of the flow structure near a diamond-shaped wing with conical conjugation consoles for sliding flow in regimes with supersonic leading edges, criteria are determined for the existence of Ferry vortex singularities in the absence of branch points of the head and internal shock waves.

Доклады Академии наук. 2019;489(6):576-580
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The new model of erosion destroying
Kuzavov V.T.
Abstract

A new physical (experimental) model of cavitation destruction of the studied materials is proposed. In the mo-dern model of the cavitation effect, the destruction of materials is associated with the impacts of cumulative jets, which are formed during the asymmetric slamming of cavitation bubbles near the solid surface and the shock waves that occur during their compression. In the new model, erosion damage is explained by the formation of cavitation tubes (с-tubes) with a spiral high-frequency structure in the materials under study that were previously unknown in the literature. The destruction of materials is associated with the focusing of acoustic energy along the axis of the spiral structures. When focusing energy, there is a significant increase in pressure and temperature along the axis of the spiral structures, which leads to the destruction of the materials under study.

Доклады Академии наук. 2019;489(6):581-584
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On the refined stress analysis in the applied elasticity problems accounting of gradient effects
Lomakin E.V., Lurie S.A., Rabinskiy L.N., Solyaev Y.O.
Abstract

The paper proposes an extension of the approaches of gradient elasticity of deformable media, which consists in using the fundamental property of solutions of the gradient theory - ​the smoothing of singular solutions of the classical theory of elasticity, converting them into a regular class not only for the problems of micromechanics, where the length scale parameter is of the order of the material‘s characteristic size, but for “macromechanical” problems. In these problems, the length scale parameter, as a rule, can be found from the macro-experiments or numerical experiments and does note have an extremely small values. It is shown, by attracting numerical three-dimensional modeling, that even one-dimensional gradient solutions make it possible to clarify the stress distribution in the constrained zones of the body and in the area of the loads application. It is shown that additional length scale parameters of the gradient theory are related with specific boundary effects and can be associated with structural geometric parameters and loading conditions that determine the features of the classical three-dimensional solution.

Доклады Академии наук. 2019;489(6):585-591
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New cases of integrable ninth-order systems with dissipation
Shamolin M.V.
Abstract

The paper shows the integrability of certain classes of ninth-order dynamic systems that are homogeneous in part, in which the system on the tangent bundle to four-dimensional manifolds is distinguished. In this case, the force fields have various dissipation and generalize the previously considered ones.

Доклады Академии наук. 2019;489(6):592-598
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Chemical Technology
Distribution of TR2O3, P2O5 and Nb2O5 between two immiscible melts in the monazite–SiO2–NaF–Nb2O5–Fe2O3 system
Delitsyn L.M.
Abstract

Monacite-SiO2-NaF-Nb2O5-Fe2O3 system on 1200 °C isotherm is characterized by a wide area of two immiscible melts: silicate and phosphate-fluoride, salt. The system is a mutual education in molten salt a new phase of rare earth double phosphates and fluoridahospital REE and Na in the composition of which is Fe and Nb. Iron has a great influence on the immiscibility of melts: in the absence of iron, the liquation area occupies 50% of the chart area, at 5% Fe2O3 - 57%, at 10% Fe2O3 - 70%. REE, P and Nb oxides are contrast distributed between the two immiscible melts. REE and P are 95% concentrated in phosphate-salt melt. Niobium is concentrated in an iron-silicate melt. In the absence of Fe2O3 in the silicate melt, the content of Nb2O5 = 4,91%, at 15,33% it = 6,89%, i.e. increased by 40%.

Доклады Академии наук. 2019;489(6):599-605
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Physical chemistry
Electrodeposition of platinum from carbon dioxide based supercritical electrolyte
Ursov E.D., Kondratenko M.S., Gallyamov M.O.
Abstract

For the first time, the electrodeposition of platinum from a carbon dioxide-based supercritical electrolyte with the addition of acetonitrile as a co-solvent and tetrabutylammonium tetrafluoroborate salt was studied.  Dimethyl (1,5-cyclooctadiene) platinum is used as a precursor. It has been established that as a result of potentiostatic electrodeposition, not a continuous film is formed, but agglomerates of densely packed platinum nanoparticles.

Доклады Академии наук. 2019;489(6):606-610
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Geology
Precambrian diamond crystals from the Siberian craton
Afanasiev V.P., Pokhilenko N.P., Egorova E.O., Leendenblot E.S.
Abstract

Analysis of diamond grains from placers in the northeastern Siberian craton shows that some diamond varieties (round dodecahedra, varieties II and V-VII in the classification of Orlov) may originate from Precambrian sources. The Precambrian diamonds have different sedimentation histories. Namely, diamonds of varieties V-VII are most strongly rounded though being the most resistant to wear. Therefore, they should have the longest history of dispersal and transport, and thus should be derived from the oldest primary deposits.

Доклады Академии наук. 2019;489(6):611-615
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Age of Ichinsky and Khangar stratovolcanoes (Sredinny range, Kamchatka)
Pevzner M.M., Lebedev V.A., Volynets A.O., Kostitsin Y.A., Babansky A.D., Tolstykh M.L.
Abstract

K-Ar isotopic age of the beginning of formation of Ichinsky (0,35 Ma) and Khangar (0,4 Ma) stratovolcanoes is established for the first time, as well as the age of the final stage of activity of the Lauchan Ridge (about 0,9 Ma) in the Sredinny Range of Kamchatka. Probably the formation of the studied volcanoes may be caused by the generation of the new deep NNE fault within the Sredinny Range of Kamchatka, which in turn was connected to the regional reasons of the increasing endogenous activity at the North-West Pacific.

Доклады Академии наук. 2019;489(6):616-620
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Mamon stratum of the upper devonian of the Voronezh anteclise - new kaolin-bearing province
Savko A.D., Novikov V.M., Boeva N.M., Krainov A.V., Milash A.V., Zhegallo E.A., Ovchinnikova M.Y., Bortnikov N.S.
Abstract

The lithofacies analysis of the Mamon showed showed that secondary kaolin deposits, forming a new kaolin-bearing province in the southern part of the Voronezh anteklise, are associated with a complex of deluvial-proluvial, lacustrine-boggy, and floodplain-oxbow deposits. The main ore minerals are kaolinite, quartz and secondary iron oxides and gibbsite. The presence of both terrigenous and autistic kaolinite was revealed. An important role in the formation of the latter, as well as gibbsite, played an organic substance.

Доклады Академии наук. 2019;489(6):621-625
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Geochemistry
Dissolution of pyrochlore and microlite in alkaline, sub-aluminous and high-aluminous granitoid melts
Chevychelov, V.Y., Virus A.A., Shapovalov Y.B.
Abstract

The represented experimental data on the Ta and Nb contents in acidic magmatic melts of different compositions, when dissolving pyrochlore and microlite at T = 650–850 °C and P = 100–400 MPa, make it possible to obtain quantitative characteristics to create physico-chemical models of the genesis of Ta–Nb deposits. At pyrochlore dissolution in granitoid melts at P = 100 MPa, the highest Nb content (0,7–1,9 wt.%) is obtained in alkaline melts, it decreases to 0,06–0,38 wt.% in sub-aluminous melts, and then slightly increases to 0,11–0,41 wt.% in high-alumina melts. An increase in temperature increases the dissolution of pyrochlore, and an increase in pressure decreases its. In high-alumina granite melts the pyrochlore is unstable. At the microlite dissolves with the increase in the alumina-rich melt, the Nb/Ta ratio in the melt increases approximately doubles.

Доклады Академии наук. 2019;489(6):626-630
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Oceanology
New data on geology of the Osborn Knoll, Indian ocean
Levchenko O.V., Marinova Y.G., Portnyagin M.V., Werner R., Lobkovsky L.I.
Abstract

The Osborne Plateau is a large intraplate elevation in the eastern part of the Indian Ocean, which has been poorly studied by geological and geophysical methods. In cruise SO258/1 on RV Sonne, were collected new data with Parasound seismic profiling and multi-beam echo sounder survey. Fractures in the sedimentary cover, which extend to the bottom surface, indicate on high neotectonic activity in the area of the Osborne Plateau. It can continue up to the present, as well as in the adjacent segment of the Ninetyeast Ridge, where strong earthquakes are recorded. Two reflectors in the upper part of the sedimentary cover mark global regressive changes in the World Ocean level at the boundary of the Miocene / Pliocene and Pliocene / Pleistocene. The reflector in the sediments at the boundary of the Lower / Upper Pliocene is associated with a change in the regional hydrodynamic regime at the time in the eastern Indian Ocean. The rocks dragged on the Osborn Knoll are identical to volcanic rocks of the Ninetyeast Ridge, confirming their assumed genetic similarity, but they are more identical to basalts of the Kerguelen plateau. Extremely modified vitroclastic tuffs appear to have been formed as a result of explosive volcanic eruptions of alkaline basalts or foidites in subaeral or relatively shallow water conditions and represent the most recent eruption in the region.

Доклады Академии наук. 2019;489(6):631-636
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Biochemistry, biophysics, molecular biology
Multifunctional ENY2 protein interacts with RNA helicase MLE
Nikolenko J.V., Kurshakova M.M., Krasnov A.N.
Abstract

ENY2 protein of Drosophila melanogaster was previously discovered and characterized in our laboratory [1]. It was found that ENY2 is a subunit of several multiprotein complexes and connects various stages of gene expression [2-4]. This work is devoted to studying the interaction of ENY2 with RNA helicase MLE. This interaction was confirmed by independent methods. Data were obtained indicating that this interaction is conserved in evolution and is important for the functioning of MLE in both sexes.

Доклады Академии наук. 2019;489(6):637-640
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Microbiology
New method of complex photo-fluorescent microbiotesting
Sibirtsev V.S., Garabadgiu A.V., Shvets V.I.
Abstract

The biotesting procedure is described, which provides for recording changes in the intensities of elastic light scattering, light absorption and intrinsic photofluorescence of the protein component, as well as determination of concentration and structuring coefficients of the genomic component of samples with viable unicellular test organisms, incubated in a liquid nutrient medium in the presence and absence of various external chemical factors. The results of the analysis using this technique of the antibiotic activity of cations of various metals are presented. It is shown that using this technique can be much more rapid, objectively and comprehensively than using standard visual microbiotesting methods, to assess the effect on reproduction rate, metabolic activity and genome structure of test organisms of samples of various products, wastes, etc.

Доклады Академии наук. 2019;489(6):641-645
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General biology
Climate and land use as key factors of the stability of organic matter in soils
Kurganova I.N., Semenov V.M., Kudeyarov V.N.
Abstract

Stocks of organic carbon in the soils and its resistance to biodegradation depend on a combination of external and internal determinants which control not only the decomposition, but also the stabilization of organic matter (OM). Soil OM stability was evaluated: 1) by specific mineralization rate (SpMinR) for the forest ecosystems located in various climatic zones of Eurasia (temperate, Mediterranean, and tropical) and 2) by the biological stability index (IBS), determined for the main soil types of the European part of Russia under natural vegetation and agricultural crops. It is shown that the key factors determining the stability of OM of substances in soils are the climate and type of vegetation (land use). Thus, a close negative correlations between the SpMinR values and the annual precipitation and the average annual air temperature were found in the soils of the Eurasian transect. It was revealed that the share of stable and biologically conservative OM and IBS values in the soils under agricultural crops were significantly higher than in the soils of natural cenoses.

Доклады Академии наук. 2019;489(6):646-650
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The CoOccurence of Hyoplagus and Lepus (Leporidae, Lagomorpha) in the early pleistocene of Crimea
Lopatin A.V.
Abstract

New fossils of Leporidae from the Lower Pleistocene deposits of the Taurida Cave in the central Crimea (Belogorsk district, Zuya village) are referred to Hypolagus brachygnathus (Kormos, 1930) and Lepus sp. Cooccurrence of Hypolagus and Lepus in the Early Pleistocene of Crimea is significant in terms of the question of the first appearance of Lepus in Europe, as well as the hypothesis of the competition with hares as one of the possible causes of extinction of Hypolagus.

Доклады Академии наук. 2019;489(6):651-653
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