Vol 485, No 4 (2019)

Mathematics
Sub-Finsler structures on the Engel group
Ardentov A.A., Sachkov Y.L.
Abstract

A one-parameter family of left-invariant sub-Finsler problems on a four-dimensional nilpotent Lie group of depth 3 with two generators is considered. The indicatrix of sub-Finsler structures is a square rotated by an arbitrary angle in the distribution. Methods of optimal control theory are applied. Abnormal and singular normal trajectories are described, and their optimality is proved. Singular trajectories arriving at the boundary of the reachable set in fixed time are characterized. A bang-bang phase flow is constructed, and estimates for the number of switchings on bang-bang trajectories are obtained. The structure of all normal extremals is described. Mixed trajectories are studied.

Доклады Академии наук. 2019;485(4):395-398
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Differential properties of semigroups and estimates of distances between stationary distributions of diffusions
Bogachev V.I., Miftakhov A.F., Shaposhnikov S.V.
Abstract

We obtain new bounds on the total variation distance and the Kantorovich distance between stationary distributions of diffusion processes in terms of certain distances between diffusion and drift coefficients.

Доклады Академии наук. 2019;485(4):399-404
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Analogues of Korn’s inequality on Heisenberg groups
Isangulova D.V.
Abstract

Two analogues of Korn’s inequality on Heisenberg groups are constructed. First, the norm of the horizontal differential is estimated in terms of its symmetric part. Second, Korn’s inequality is treated as a coercive estimate for a differential operator whose kernel coincides with the Lie algebra of the isometry group. For this purpose, we construct a differential operator whose kernel coincides with the Lie algebra of the isometry group on Heisenberg groups and prove a coercive estimate for this operator. Additionally, a coercive estimate is proved for a differential operator whose kernel coincides with the Lie algebra of the group of conformal mappings on Heisenberg groups.

Доклады Академии наук. 2019;485(4):405-409
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On minimal surfaces on two-step Carnot groups
Karmanova M.B.
Abstract

For graph mappings constructed from contact mappings of arbitrary two-step Carnot groups, conditions for the correct formulation of minimal surfaces’ problem are found. A suitable notion of the (sub-Riemannian) area functional increment is introduced, differentiability of this functional is proved, and necessary minimality conditions are deduced. They are also expressed in terms of sub-Riemaninan mean curvature.

 

Доклады Академии наук. 2019;485(4):410-414
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Outer billiards outside a regular dodecagon
Rukhovich F.D.
Abstract

The existence of an aperiodic orbit for an outer billiard outside a regular dodecagon is proved. It is shown that almost all orbits of such an outer billiard are periodic, and all possible periods are explicitly listed. The proofs of the theorems make use of computer calculations.

Доклады Академии наук. 2019;485(4):415-421
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Technical Physics
Normal glow discharge: comparison of calculated and experimental data
Surzhikov S.T., Kozlov P.V., Kotov M.A., Ruleva L.B., Solodovnikov S.I.
Abstract

The combined numerical and physical modeling of a glow discharge between plane disk electrodes in molecular nitrogen is performed at pressures р = 3 and 5 Tor. The satisfactory description of experimental data by the drift-diffusion model is shown. The simultaneous analysis of experimental and calculated data has permitted identification of the normal burning regime of a glow discharge. However, the essential effect of model parameters such as the secondary electron emission coefficient and the first Townsend coefficient on the calculated voltage-current characteristic has been demonstrated in this case.

Доклады Академии наук. 2019;485(4):422-427
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Mechanics
An analogy between electromagnetic and internal waves
Baydulov V.G., Lesovskiy P.A.
Abstract

For the symmetry group of internal-wave equations, the mechanical content of invariants and symmetry transformations is determined. The performed comparison makes it possible to construct expressions for analogs of momentum, angular momentum, energy, Lorentz transformations, and other characteristics of special relativity and electro-dynamics. The expressions for the Lagrange function are defined, and the conservation laws are derived. An analogy is drawn both in the case of the absence of sources and currents in the Maxwell equations and in their presence.

Доклады Академии наук. 2019;485(4):428-433
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Exact solution of problems of diffraction of unsteady waves on a wedge under mixed boundary conditions by the Smirnov-Sobolev method
Israilov M.S.
Abstract

Antil now, the Smirnov-Sobolev method has been applied only to diffraction problems with the Dirichlet and Neumann boundary conditions. In this study, it is shown that the method also leads to an exact solution of the mixed problem of diffraction on a wedge, which is very important, for example, for estimating the possibility of protection from blast waves by wedge-shaped barriers with different reflecting properties of the sides.

Доклады Академии наук. 2019;485(4):434-437
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On the problem of thermoacoustics of conductive materials under laser irradiation
Morozov N.F., Muratikov K.L., Semenov B.N., Indeitsev D.A., Vavilov D.S.
Abstract

Within the framework of the one-temperature model of thermoelasticity, the analysis of the effect of electon localization processes on the thermoelastic response of conductors under pulsed laser irradiation is performed. It is shown that the localization of electrons can lead to a significant tightening of the deformation processes in conductors compared with the processes that develop according to the usual thermoelastic mechanism.

Доклады Академии наук. 2019;485(4):438-441
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Chemistry
Mixed-ligand gallium complexes with N-vinylpyrrolidone- N-vinylformamide-N-vinyliminodiacetic acid terpolymers containing dithiocarbamates as a coligand
Gorshkov N.I., Murko A.Y., Gavrilova I.I., Malakhova I.I., Krasikov V.D., Panarin E.F.
Abstract

Terpolymers with a molecular weight of 65 and 13 kDa containing 90 mol.% of N-vinylpyrrolidone, 7 mol.% of N-vinylformamide, and 3 mol.% of N-vinyliminodiacetic acid units have been synthesized. Diethyldithiocarbamate and benzyldithiocarbamate have been used as coligands. The mixed-ligand complexation with Ga3+ ion has been studied by HPLC. The composition and structure of the resulting metal-polymer complexes have been determined by exclusion chromatography and spectral (IR, 1H NMR) data.

Доклады Академии наук. 2019;485(4):442-446
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Synthesis and hydrophobic properties of poly[(perfluoro-tret-hexyl)bytylmethacrylate]
Mel’nik O.A., Kondratenko М.S., Tyutyunov A.A., Igumnov S.M., Khokhlov A.R.
Abstract

A new fluorinated polymethacrylate with perfluoro-tret-hexyl groups in the side chain has been prepared by radical polymerization. Polymer films applied from solutions in supercritical carbon dioxide enables the preparation of superhydrophobic coatings.

Доклады Академии наук. 2019;485(4):447-450
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Physical chemistry
Polymer-inorganic composites based on Celgard matrices obtained using solutions of (aminopropyl)triethoxysilane in supercritical carbon dioxide
Elmanovich I.V., Zefirov V.V., Sizov V.E., Kondratenko M.S., Gallyamov M.O.
Abstract

A method has been developed for the fabrication of a polymer-inorganic composite material based on the Celgard polymer matrix by means of the introduction of silica nanoparticles with amino groups into the polymer structure through impregnation of porous structure with solutions of the aminosilane precursor in supercritical СO2. The presence of inorganic nanoparticles made it possible to noticeably enhance the hydrophilicity of the material, and the absolute wetting ability of supercritical CO2 was favorable for uniform particle distribution in membrane pores. The particles growing in membrane pores allowed one to reduce the pore size, which opens ways to control ion-transport selectivity.

Доклады Академии наук. 2019;485(4):451-456
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Geology
Late Ordovician volcanism of the northern part of Altai-Sayan area and its geodynamic nature
Vorontsov A.A., Perfilova O.Y., Kruk N.N., Tarasyuk A.S.
Abstract

The results of geological-geochemical studies of some Late Ordovician associations in the frame of the Minusinsk Trough with available geological and U-Pb, Rb-Sr, and K-Ar age dates are presented. The Late Ordovician volcanic rocks form a continuous igneous series, the basalts of which are different from Devonian basalts of the Minusinsk Trough in the lower TiO2 content (≥1.7 wt %) and more fractionated REE pattern. These features should be considered the index characteristics of Late Ordovician rocks. Their compositions reflect processes of fractionation crystallization and mixing of trachibasaltic magmas with crustal melts. When taking into account the regional geological data, it is shown that magmatic activity at the Late Ordovician endogenic evolution stage in the northern part of the Altai-Sayan fold area was caused by the interaction of a mantle plume and the lithospheric mantle, which was metasomatically reworked and enriched in water during former subduction processes.

Доклады Академии наук. 2019;485(4):457-463
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New data on the mineral composition of unique rhenium U-Mo-Re ores of the Briketno-Zheltukhinskoe deposit in the Moscow Basin
Engalychev S.Y.
Abstract

Data on the mineral composition of Re-rich U-Mo-Re ores from the Briketno-Zheltukhinskoe deposit that were obtained using state-of-the art analytical equipment are presented for the first time. The deposit is confined to Lower Carboniferous (Missisipian) coal-bearing strata in the Moscow Basin. The found mineral association of Re ores has made it possible to identify the most likely rhenium carrier minerals. They are Mo-containing minerals: wulfenite, ilsemannit, ferrimolybdite, and kamiokite. Re is hosted by them and partly replaces Mo in the structure. The association of Re with U, Mo, Se, Ag, V, Tl, As, Ni, Co, and dispersed organic matter is recorded.

Доклады Академии наук. 2019;485(4):464-467
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40AR/39AR age of the Albyn gold ore deposit (eastern part of the Mongol-Okhotsk fold belt)
Kadashnikova A.Y., Sorokin А.А., Ponomarchuk A.V., Travin А.V., Ponomarchuk V.А., Dementienko A.I., Eirish L.V.
Abstract

It was established that the age of hydrothermal metasomatites of the Albyn gold deposit, one of the most famous in eastern Asia, can be estimated at 135-131 Ma. It is assumed that the formation of this deposit is associated with dislocations and metamorphism of volcanogenic-sedimentary strata of the Mongol-Okhotsk belt.

Доклады Академии наук. 2019;485(4):468-473
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Geochemistry
Age and sources of detrital zircons from Jurassic conglomerates of the Strelka Depression (northern frame of the Mongol-Okhotsk fold belt)
Zaika V.A., Sorokin A.A., Kovach V.P., Sorokin A.P., Kotov A.B.
Abstract

The article presents the results of U-Th-Pb geochronological studies of clastic zircons from cement of the Jurassic conglomerates of the Strelka Depression extended in a sublatitudinal direction along the border between the southern margin of the Selengino-Stanovoy Superterrane and the Mongol-Okhotsk fold belt. It has been shown that Paleoproterozoic and Neoarchean zircons dominate in the conglomerate cement. This indicates that the main demolition of the material to the sedimentation basin was carried out from the southeastern frame of the North Asian Craton (from the north in modern coordinates). In our view, the Strelka Depression formed after the completion of orogenic processes associated with the formation of the Mongolo-Okhotsk structure.

Доклады Академии наук. 2019;485(4):474-478
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JPD-analysis as a new approach for studying the zircon texture with micron spatial resolution with application to geochronology
Zamyatin D.A., Votyakov S.L., Shchapova Y.V.
Abstract

The polygenic and polychronous character of zircon texture is the key source of information on the conditions of its growth and secondary alterations. In this research the JPD method of processing of the BSE and CL images including plotting of JPD histograms and JPD maps of grains was developed and applied for quantitative study of the internal texture of zircon grains with micron spatial resolution and for its use in geochronometry. The nomenclature for distinguished zones on the generalized diagram (BSE vs. CL) is suggested for zircons of a wide range of the conditions of its formation, age, size, texture types, and degrees of structure disordering. The JPD-analysis of zircon internal texture is applied for interpretation of the nature of variations in the BSE and CL intensities within an individual heterogeneous grain (on the quantitative level) and between different grains (on the qualitative level). The approach is suggested as the preliminary stage during geochronological studies increasing the reliability of the local electron microprobe and mass spectrometry isotope dating of the mineral.

Доклады Академии наук. 2019;485(4):479-483
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Mineralogy, trace element composition, classification of Onello high-Ni ataxite
Litasov K.D., Ishikawa A., Kopylova A.G., Podgornykh N.M., Pokhilenko N.P.
Abstract

The trace element composition of the Onello meteorite is analyzed in detail using SEM and LA-ICP-MS. The following Ni contents of minerals are determined (wt %): 23.0-25.4 in taenite, 5.8-8.8 in kamacite, 22-26 in schreibersite, 44-52 in nickelphosphide, 20.6-21.8 in allabogdanite, and 75-81 in awaruite. In the trace element content, the Onello meteorite corresponds to the IAB group of iron meteorites. Inside this group, it mostly matches the sHH subgroup (with high Au and Ni contents). The presence of allabogdanite in the meteorite indicates the high PT parameters of its formation: >8 GPa and 1000-1400 °C. Thus, the formation of the Onello meteorite is related to impact metamorphism of a parental body of iron meteorites of the IAB group and vinonaites, in which a P- and Ni-rich area underwent melting and further crystallization.

Доклады Академии наук. 2019;485(4):484-487
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First results of U-Pb LA-SF-ICP-MS-dating detrital zircons from the middle riphean (?) terrigenous deposits of the Polar Urals
Ulyasheva N.S., Pystina Y.I., Pystin A.M., Grakova O.V., Hubanov V.B.
Abstract

The first results of U-Pb LA-SF-ICP-MS-dating of detrital zircons from terrigenous deposits of the Miniseishor suite of the Nyarovei series of the Harbei anticlinorium of the Polar Urals are presented. The series has a presumably Middle Riphean age and lies at the base of the section of the Polar Ural Upper Precambrian. The data obtained give grounds to limit the lower age interval for the formation of sediments of the Minisejshor suite abroad 660 million years ago. Allotment the Nyarovei series as a Middle Riphean straton is erroneous. Formation of the whole cut the Nyarovei series occurred in a relatively narrow age range at the end of the late Riphean. The dominant role in the formation of deposits of the entire series belonged to the products of erosion close arrays of deeply metamorphosed rocks.

Доклады Академии наук. 2019;485(4):488-492
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Geophysics
Structure of the terrain and gravitational field of the planets: Kaula’s rule as a consequence of the probability laws by A.N. Kolmogorov and his school
Gledzer E.B., Golitsyn G.S.
Abstract

Kaula’s empirical rule has been known for more than 50 years: the coefficients of expansion over spherical harmonics for the fluctuations of the gravitational field and terrain of the planets decrease as the number of the harmonic squared. This was found for Venus, the Moon, Mars, the asteroid Vesta, and very small celestial bodies. The inverse-square line spectra were also found for various types of the Earth’s surface on a scale of up to a hundred kilometers. From this it follows that the spectra of the terrain slope angles are constant, i.e., “white noise”. This, they are delta-correlated horizontally. These are the assumptions under which the random walk laws were derived by A.N. Kolmogorov in 1934. Using them, the equation of the horizontal probability diffusion of the terrain with the linear coefficient diffusion D is derived. Based on the empirical data, D = 1.3 ± 0.3 m for the Earth, while for Venus it is almost an order of magnitude less. The slopes resist the wind; the rock crumbles, and the water flows down the slopes as well. This consideration turns Kaula’s rule into the random walk laws (over terrain) developed by Kolmogorov in 1934.

Доклады Академии наук. 2019;485(4):493-496
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Low frequency seismic noise before and after the Sumatra megaearthquake December 26, 2004
Sobolev G.A.
Abstract

The paper aims at detailed study of the structure of seismic noise before and after the Sumatra mega-earthquake with M = 9.1 of December 26, 2004. The records by IRIS seismic stations in the different regions of the world, equipped with STS-1 seismometers providing ground motion velocity recording in a broad range of periods from 0.2 to 360 s with the use of standard equipment, form the empirical base of the research. In the records by each station, the intervals free of the earthquakes, interference of manmade impacts, and noise enhancement due to cyclone propagation were selected. The noise bursts in the ranges 40-80, 80-160, and 160-320 s differ by the shape and time of occurrence suggesting different sources of their generation. The absence of the correlation between the noise recordings at the neighboring seismic stations spaced 102 - 103 km apart indicates the influence of local processes. The noise reflects turbulent processes in the Earth’s atmosphere whereas the exponential growth of the noise with the increase of the oscillation period is consistent with A.N. Kolmogorov’s theory of locally isotropic turbulence in the atmosphere. The noise amplitude after the Sumatra mega-earthquake with M = 9.1 of December 26, 2004 has increased by a factor of 1.5-2 in January 2005 compared to January 2004 irrespective of the location of a seismic station.

Доклады Академии наук. 2019;485(4):497-501
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Oceanology
New look at the water exchange between the Arctic and North Atlantic in Iceland basin
Gladyshev S.V., Gladyshev V.S., Klyuvitkin A.A., Gulev S.K.
Abstract

Based on the multi-year current observations along 59.5 N in the Subpolar North Atlantic multi-jet transport of arctic water along Reykjanes Ridge eastern slope producing Iceland-Scotland overflow water (ISOW) in Iceland Basin is revealed. Main jet properties as well as their contribution to the deep water transport are discussed.

Доклады Академии наук. 2019;485(4):502-506
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Monitoring the circulation of coastal waters off the Southern coast of Crimea
Ivanov V.A., Kuznetsov A.S., Morozov A.N.
Abstract

The paper presents the results of integrated monitoring of water dynamics in the coastal zone off the Southern coast of the Crimea for 2008-2016. The regime and features of circulation of coastal waters were determined. An intensive contribution of low-frequency oscillations of coastal currents at the seasonal and synoptic scales was identified based on the results of spectral analysis of a nine-year set of vector dynamics series. For water fluctuations in the coastal zone, the alongshore structure of reciprocating jet streams caused by water dynamics at the shelf and continental slope dominates.

Доклады Академии наук. 2019;485(4):507-510
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Biochemistry, biophysics, molecular biology
Singlet-triplet fission of carotenoid excitation in the purple phototrophic bacteria Thermochromatium tepidum
Klenina I.B., Gryaznov A.A., Makhneva Z.K., Proskuryakov I.I.
Abstract

Confirmation of intermolecular mechanism of excitation fission involving two carotenoid molecules in the purple phototrophic bacteria Thermochromatium tepidum is obtained.

Доклады Академии наук. 2019;485(4):511-514
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The development of reporter system for the investigation of molecular mechanisms of ecdysone response
Mazina M.Y., Krasnov A.N., Georgiev P.G., Vorobyeva N.E.
Abstract

To study the mechanisms of transcriptional regulation, a convenient experimental approach is to use the artificial chimeric constructs, carrying the regulatory elements of interest. In the present work, we describe the creation and characterization of a novel genetic construct, which makes possible to study the transcriptional regulation of the early-late gene of the ecdysone cascade. Using the data of genome-wide experiments, we have isolated the main regulatory region of the hr4 gene, which was successfully used to create a chimeric reporter construct expressing a fluorescent protein upon the treatment with the ecdysone hormone. This reporter system can be used to study the mechanisms of the ecdysone response, both in cell culture and in tissues, at various stages of the Drosophila development.

Доклады Академии наук. 2019;485(4):515-518
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General biology
Trophosome in vestimentifera Ridgeia piscesae Jones, 1985 (Annelida, Siboglinidae) develops from cells of the coelomic lining
Malakhov V.V., Gantsevich M.M.
Abstract

The structure of early juvenile specimens of vestimentifera Ridgeia piscesae (Annelida, Siboglinidae) was studied. As adults, vestimentiphers are deprived of the intestine and have a trophosome, in which cells chemoautotrophic bacteria are living. In early juvenile individuals of 280-300 microns in size, it was found that trophosome develops from cells of the coelomic lining on the surface of the intestine and on the side walls of the body. This structure of the rudiment of the trofosome suggests that the bacteria are first captured by the cell wall of the body and then transferred to the cell on the surface of the intestine.

Доклады Академии наук. 2019;485(4):519-522
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Systematics and distribution of ferret badgers Melogale (Mammalia, Mustelidae) in Vietnam: first genetic data
Rozhnov V.V., Korablev M.P., Abramov A.V.
Abstract

Genetic studies of the ferret badgers Melogale conducted in Vietnam have shown that this area is inhabited by three species, M. moschata, M. personata, and M. cucphuongensis, which can be attributed to sibling species (cryptic species). M. personata was found to be widespread not only in southern and central Vietnam, but also in the northern provinces (Lang Son, Ha Giang, Ninh Binh), while M. cucphuongensis was found in the provinces Lang Son, Ha Giang, Cao Bang, and Dak Lak, apart from Ninh Binh, from where it was described. The data obtained suggest a sympatric distribution of all three species over the Vietnam area and confirm sympatry of M. personata and M. moschata in southern Vietnam, which has been earlier established on the basis of morphological data.

Доклады Академии наук. 2019;485(4):523-528
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