Vol 487, No 3 (2019)

Mathematics

On the energy current for the harmonic crystals in the half-space

Dudnikova T.V.

Abstract

We consider the dynamics of the harmonic crystal in the half-space with zero boundary condition. We assume that the initial data are a random function. We prove the convergence of the distributions of the solutions to a limiting measure for large times. The formula for the limiting energy current density (in mean) is derived. The application to the case of the Gibbs initial measures is given. We find the stationary non-equilibrium states, in which there exists a non-zero heat flow passing through the points of the crystal.

Доклады Академии наук. 2019;487(3):235-237
pages 235-237 views

High excursions of Bessel process and other processes of Bessel type

Piterbarg V.I., Rodionov I.V.

Abstract

A high excursion probability for the modulus of a Gaussian vector process with independent identically distributed components is evaluated. It is assumed that the components have means zero and variances reaching its absolute maximum at a single point of the considered time interval. An important example of such processes is the Bessel process.

Доклады Академии наук. 2019;487(3):238-241
pages 238-241 views

Mathematical physics

Many-dimensional tauberian theorems for holomorphic functions of bounded argument

Drozhzhinov J.N.

Abstract

For generalized functions with Laplace transform has nonnegative imaginary part in tube domain over positive actant, we found sufficient conditions for existence of quasiasymptotic, the function with regular behavior with respect to which the quasiasymptotic exists being explicitly found. The obtained results are used to steady of the asymptotic behaviour of solutions of the Cauchy problem of passive operators.

Доклады Академии наук. 2019;487(3):242-245
pages 242-245 views

Physics

Approximation of the n-vicinity method

Kryzhanovsky B.V.

Abstract

We determined a small parameter that determines the possibility of using the n-vicinity 06_method to calculate the free energy of a spin system, and found the types of spin systems for which this method is applicable. It is shown that this method is applicable for the analysis of spin systems, where the number of nearest neighbors is greater than 16/3.

Доклады Академии наук. 2019;487(3):246-251
pages 246-251 views

Technical Physics

The influence of cavitation and the degree of overlap of the flow of cylindrical flow bodies on the flow pattern, hydrodynamic and spectral characteristics of a flat-type hydrodynamic generator

Ganiev S.R., Shmyrkov O.V., Rudakov V.P.

Abstract

The paper presents the results of studies of flow behind cylindrical flow bodies in a flat-flow hydrodynamic generator, obtained on the hydrodynamic bench of the experimental base of the National Scientific Center NBMT RAS with the degree of flow blocking by flow bodies St/S0 = 10-80%, Re numbers (0,5-5) · 105, PVH inlet pressure = 0,1-0,8 MPa. It was found that with the same pressure drop two different types of flow can be realized behind the flow bodies: with a developed cavitation zone, within which there is an extensive low pressure area and without it, but with the formation of vortex structures with the presence of centers of cavitation bubbles in them. At a certain value of input to output pressure, which is constant for each value of the degree of overlap of the flow, powerful pressure peaks of the resonant type arise with an amplitude of 2-2,5 times the maximum value of the input pressure. The frequency of occurrence of these pressure peaks increases linearly with increasing pressure drop, and decreases by an order of magnitude with an increase in the degree of overlap of flow up to 80%. The frequency dependence of the number Re for each value of St/S0 is linear. The value of the Strouhal number St with an increase in St/S0 increases linearly with St/S0 = 0,82 and the value St = 1,2.

Доклады Академии наук. 2019;487(3):252-256
pages 252-256 views

Mechanics

Optimal disturbances of stably stratified turbulent Couette flow

Glazunov A.V., Zasko G.V., Mortikov E.V., Nechepurenko Y.M.

Abstract

Direct numerical simulation data of a stably stratified turbulent Couette flow contains two types of organized structures: the rolls that arise at neutral and close to neutral stratification, and the layered structures, which manifest themselves as the static stability increases. It is shown that both types of structures have spatial scales and forms that coincide with the scales and forms of the corresponding optimal disturbances of the simplified linear model of the Couette flow with the same Richardson numbers.

Доклады Академии наук. 2019;487(3):257-261
pages 257-261 views

Chemistry

A new approach to the synthesis of thiacrowns on a thiacalix[4]arene scaffold

Muravev A.A., Yakupov A.T., Solovieva S.E., Antipin I.S.

Abstract

A new strategy of synthesis of thiacalix[4]monothiacrown-ethers in 1,3-alternate stereoisomeric form has been suggested and implemented through macrocylization of the lower rim of 3-bromopropoxy-substituted thiacalixarene by dithiols.

Доклады Академии наук. 2019;487(3):262-265
pages 262-265 views

Catalytic isomerization of substituted vinylcyclopropanes

Raskil’dina G.Z., Borisova Y.G., Davletshin A.R., Zlotsky S.S.

Abstract

The catalytic isomerization of substituted vinyl-gem-dichlorocyclopropanes was studied in the presence of a series of zeolite catalysts. It is shown that the only reaction products are substituted gem-dichlorocyclopentenes. The influence of a number of factors (type of catalyst, temperature, reaction time) on the yield of isomerization products was investigated.

Доклады Академии наук. 2019;487(3):266-269
pages 266-269 views

Chemical Technology

Mineral-polymer composites based on hydroxyapatite with polyvynylpyrrolidon for medicine

Fadeeva I.V., Grabovenko F.I., Fomin A.S., Barinov S.M., Murzakhanov F.F., Ahmed A.I., Mamin G.V.

Abstract

Composites of hydroxyapatite (HA) with polyvinylpyrrolidone (PVP) were synthesized by precipitation in water solutions, mass relations of HA/PVP varied in region 3,6-14,5. The composite materials were investigated using XRD, IR, electron paramagnetic resonance (EPR) spectroscopy and transmission electron microscopy (TEM). Based on the TEM results it was found that during calcination of composites at 400 °C small agglomerates consisting of individual crystalline HA particles were formed, resulting in a particle size (according to TEM) slightly larger than coherent scattering region. Using the method of photoinduced EPR spectroscopy confirmed the presence of interaction between HA and PVP. The resulting composites can be used as materials for reconstructive surgery.

Доклады Академии наук. 2019;487(3):270-274
pages 270-274 views

Physical chemistry

Inhibition of oxidated reducing reactions in the field of low frequency impacts

Fadeev G.N., Boldyrev V.S., Bogatov N.A., Nikolaev A.L.

Abstract

The effect of low-frequency oscillations on a system consisting of two biochemically active components: the dye of methylene blue and ascorbic acid is investigated. Each of these components can be reversibly oxidized and reduced. The system is interesting in that it makes it possible to trace the influence of the low-frequency acoustic field on the mutual redox process and to reveal the features of the effect of such oscillations. It was found that, in this system, with the introduction of low-frequency effects, redox processes are not accelerated, but slowed down. There is an effect inhibition of the sound-chemical process in the field of low-frequency acoustic effects. The effect is quantified.

Доклады Академии наук. 2019;487(3):275-278
pages 275-278 views

Geology

About morphology and genesis of washout-like structures in a coal seam at an object in the Eastern Donbas

Mokhov A.V.

Abstract

Based of study of the morphological features of a coal seam in a mine of the Eastern Donbas, the mineral and coal elements of the object studied were identified as a single sedimentary association of a pseudo-washout nature. Specific criteria for attributing coal-bearing structures to epigenetic or syngenetic washouts of a coal seam were elaborated.

Доклады Академии наук. 2019;487(3):279-282
pages 279-282 views

Late stages in the evolution of the late Mesozoic East Mongolian volcanic areal: rock age and composition

Yarmolyuk V.V., Kudryashova E.A., Kozlovsky A.M.

Abstract

The Mandakh-Madal-Gobi (MMG) zone of alkali basalt magmatism has been delineated in the Late Mesozoic East Mongolian volcanic areal. It comprises clusters of igneous rock bodies and isolated stocks, domes, sills, laccoliths, dikes, and limited fragments of lava flows composed of tephrite, phono-tephrite, and trachybasalt. Two pulses of magmatism in the MMG zone have occurred in the Late Cretaceous (about 85 Ma) and Early Cenozoic (about 50 Ma). Recognition of this zone and deciphering of its formation history demonstrated that the development of the entire East Mongolian volcanic areal had the same regularities as those identified in other major regions of the Late Mesozoic Central Asia magmatic province. This indicates that the areal undoubtedly belongs to the latter. These facts support the conclusion that the correlation observed through the zone’s evolution between reduction in the volume of igneous products and the change in their composition towards the OIB was apparently determined by a decrease in the effect of thermal sublithospheric mantle melts upon a metasomatically enriched lithospheric mantle, leading to its gradual elimination from the magma sources.

Доклады Академии наук. 2019;487(3):283-288
pages 283-288 views

Geochemistry

Hydrothermal synthesis of framed titanosilicates with a structure of ivanyukite mineral

Gerasimova L.G., Nikolaev A.I., Shchukina E.S., Maslova M.V.

Abstract

The phase formation in the Na2O-TiO2-SiO2-H2SO4-H2O system during hydrothermal has been studied. The obtained data were used for the producing of a new type of sorbents with a frame structure similar to the mineral ivanyukite. Excess amounts of silicon and sodium in relation to titanium (III) and titanium (IV) as well as pH up to 12 provide “supersaturating” of the salt mass and affect the rate of precipitation, phase composition, structure and surface properties. The framework arrangement of SiO4 tetrahedron and TiO6 octahedron create channels where Na+ and water molecules are located. The structure of ivanyukite along with mesoporosity provides its high ion-exchange properties.

Доклады Академии наук. 2019;487(3):289-292
pages 289-292 views

Sources of eocene magmatism of Western Kamchatka (according to geochemical and isotope Sr-Nd-Pb characteristics of basites)

Fedorov P.I., Perepelov A.B., Kovalenko D.V., Dril S.I., Lobanov K.V.

Abstract

The isotope-geochemical characteristics of the Eocene-Oligocene magmatic rocks of Western Kamchatka were studied. It is shown that the igneous rocks of the Eocene (45-53 Ma) Kinkil complex of Western Kamchatka are characterized by geochemical signs of super-subduction volcanism. Their isotopic composition of Sr, Nd and Pb, low concentrations of HFSE and HREE relative to the composition of MORB, suggest the formation of primary melts from depleted or poorly enriched in isotopic composition of the mantle wedge sources in different contaminated quartz-feldspath sialic sediments. From the end of the Middle Eocene on the territory of Western Kamchatka, K-Na alkaline-basalt magmatism (46-31 million years), whose geochemical characteristics are similar to E-MORB, as well as ultrapotassic alkaline-basalt magmatism, which continued to develop to the early Miocene (35-17 million years). The geodynamic nature of Late Paleogene alkaline magmatism involves the implementation of processes of diffuse rifting.

Доклады Академии наук. 2019;487(3):293-298
pages 293-298 views

Geophysics

Variations of the parameters of internal gravity waves in the atmosphere of Central Asia before earthquakes

Adushkin V.V., Nifadiev V.I., Chen B.B., Popel S.I., Kogai G.A., Dubinskii A.Y., Weidler P.G.

Abstract

Based on the data of experimental studies of wave disturbances in the Earth’s atmosphere before and after the earthquakes in Uzbekistan (May 26, 2013) and Kyrgyzstan (January 8, 2007), earlier unknown changes in the parameters of internal gravity waves are revealed. These changes were manifested during the period of five days before the earthquake and in certain cases can be used for short-term prediction of the time when seismic events are to occur.

Доклады Академии наук. 2019;487(3):299-303
pages 299-303 views

Structure of the Khatanga-Lomonosov fracture zone according to seismic data

Shipilov E.V., Lobkovsky L.I., Shkarubo S.I.

Abstract

According to the results of geophysical data interpretation considered the structural features of the Khatanga-Lomonosov fracture zones (HLZ), adapted to the strip joint part on the Laptev Sea continental margin with the structures of the spreading of the Eurasian basin and the Lomonosov ridge. Its reflection in anomalous geophysical fields, in a wave seismic picture on sections is shown on the example of separate links of HLZ and the character of its kinematic interrelations with heterogeneous tectonic elements is illustrated. The tectonic nature, role and place of this fault zone in the geodynamic evolution of the region are substantiated.

Доклады Академии наук. 2019;487(3):304-309
pages 304-309 views

Geography

Estimation of the thermodynamic parameters of land cover from multispectral measurements of reflected solar radiation (Landsat) in terms of nonextensive statistical mechanics

Puzachenko Y.G., Krenke A.N., Puzachenko M.Y., Sandlerskii R.B., Shironya I.I.

Abstract

The use of the apparatus of nonadditive statistical mechanics for the evaluation of thermodynamic ecosystem variables based on multispectral measurements of reflected solar radiation is discussed. The parameter q is accepted corresponding to the conditions of the Förster’s maximum of organization. On the basis of remote information (Landsat) the entropy, Kullback information, Förster measure of organization, free energy, exergy, bound and internal energy, energy costs for evapotranspiration and photosynthesis for q-index values measured for each pixel of remote sensing scenes. It is shown that the seasonal dynamics of the q-index and the organization measures fully correspond to consequences that follow from the theory of open nonequilibrium systems, and thermodynamic variables reflect well the current state of ecosystems.

Доклады Академии наук. 2019;487(3):310-316
pages 310-316 views

Results of cryotrasologic indication of paleosols encountered to the north of the European and West-Siberian Loess belt

Sheinkman V.S., Melnikov V.P., Sedov S.N., Rusakov A.V.

Abstract

Rock freezing affects the soil complexes under maximal temperature gradients and forms a set of specific cryotrasological features in the solid soil matrix. When preserved these features serve as direct or indirect indicators of the past cryogenic conditions. Transformation of soil material on macro- and microscale belongs to the direct indicators whereas gleying in the well-drained positions, conditioned by the permafrost waterlogging is an indirect indicator. A variety of these features observed in the paleosols to the north of the European and West Siberian Loess belt was used by the authors to reconstruct the cryogenic environments of the late Pleistocene.

Доклады Академии наук. 2019;487(3):317-321
pages 317-321 views

Oceanology

On deep-water reception of pseudorandom acoustical signals propagating from the shelf zone to the deep ocean

Akulichev V.A., Morgunov Y.N., Golov A.A., Kamenev S.I., Petrov P.S.

Abstract

The results of an experiment conducted in September 2017 to substantiate the applicability of the “acoustic mudslide” effect when solving the positioning problems of autonomous underwater vehicles in cases of their operation at depths substantially exceeding the depth of the axis of the underwater sound channel are discussed. The results of the experimental studies and numerical analysis of the effect of an acoustic energy focusing in the near-bottom layer of the shelf and its transition into deep-water (up to 500 m) layers of the Sea of Japan for summer-autumn hydrological conditions are presented. Mathematical modelling of the propagation of acoustic waves in a model waveguide reproducing the experimental conditions using the parabolic equation method has been performed. The observed effective signal propagation speeds are explained using the normal wave method.

Доклады Академии наук. 2019;487(3):322-327
pages 322-327 views

Carbonate characteristics of the Gulf of Anadyr waters

Pipko I.I., Pugach S.P., Savelieva N.I., Luchin V.A., Dudarev O.V., Sergienko V.I., Semiletov I.P.

Abstract

The first field data describing the dynamics of the carbonate system, aragonite saturation state, and CO2 fluxes between the ocean and the atmosphere in the Gulf of Anadyr in the late autumn season are presented. It was established that during this period the gulf waters absorbed carbon dioxide from the atmosphere at a rate of -22,5 mmol m2 day1, which determined the “classical” mechanism of seawater acidification due to uptake of excess atmospheric CO2. In general, surface waters of the gulf were supersaturated with respect to aragonite. The exception was the highly dynamic region of Anadyr Strait, where the vertical distribution of the investigated parameters was homogeneous, the surface waters were close to equilibrium with respect to aragonite, and CO2 flux was directed to the atmosphere. Bottom waters of the gulf, in contrast, were characterized by significant seasonal corrosivity with respect to aragonite due primarily to remineralization of organic matter to CO2. It was shown that during the late fall relatively salty and acidic, quasi-equilibrium with respect to aragonite, and oxygen-depleted waters with high concentrations of nutrients and CO2 have been entered the Chirkov Basin and further the Arctic Ocean with the Navarin current.

Доклады Академии наук. 2019;487(3):328-332
pages 328-332 views

Biochemistry, biophysics, molecular biology

Effect of zinc excess and low temperature on the IRT1 gene expression in the roots and leaves of barley

Kaznina N.M., Titov A.F., Repkina N.S., Batova Y.V.

Abstract

We studied the effect of zinc excess (1000 µM) and low temperature (4 °C) on the IRT1 gene expression in barley roots and leaves. Exposure at each of the stress factors separately, induced an increase in the content of the HvIRT1 gene transcripts, more pronounced in the leaves. At the same time, growth of seedlings continued. Under the combined action of factors in the first 3 days, the amount of mRNA also increased, but after 7 days of exposure it significantly declined, which corresponded with a complete inhibition of seedlings growth. It is assumed that the seedlings growth inhibition under the combined effect of the zinc excess and low temperature is associated with a decrease in the transcriptional activity of the HvIRT1 gene, due to the deficiency of a number of trace elements under these conditions.

Доклады Академии наук. 2019;487(3):333-337
pages 333-337 views

Ethylene-insensitive Arabidopsis mutants etr1-1 AND ein2-1 have decreased freezing tolerance

Popov V.N., Deryabin A.N., Astakhova N.V., Antipina O.V., Suvorova T.A., Alieva G.P., Moshkov I.E.

Abstract

The freezing tolerance of Arabidopsis thaliana (L.) Heynh. was studied in relation to functioning of the ethylene signaling pathway. Constitutive freezing tolerance was compared in wild-type plants (ecotype Col-0) and ethylene-insensitive mutants etr1-1 and ein2-1. For the first time it was established that ethylene-insensitive mutants had by 25-30% lower net photosynthesis rate, the decreased content of soluble sugars and, as a result, lower freezing tolerance. Our work provides evidence that perception and transduction of ethylene signal are necessary for constitutive tolerance of Arabidopsis to low temperature.

Доклады Академии наук. 2019;487(3):338-341
pages 338-341 views

General biology

Stimulation of seed germination by humic substances: on the nature of the phenomenon

Shoba S.A., Salimgareeva O.A., Gorepekin I.V., Fedotov G.N., Stepanov A.L.

Abstract

The effect of soil compared to sand on the germination of wheat seeds and the development of their seedlings, as well as the effect of seed treatment with humic substances on their development in sand and soils was studied. For a number of the Russian Plain soils, it was shown that the soils inhibit seed germination significantly. It was established that pre-sowing treatment of seeds with humic preparations has a noticeable stimulating effect when sowing treated seeds in sod-podzolic soil and has no effect practically when sowing these seeds in sand. On the basis of the known phenomenon of soil allelotoxicity, it was suggested that the stimulating effect of humic substances on seed development is to limit the influence of allelotoxins on their development.

Доклады Академии наук. 2019;487(3):342-345
pages 342-345 views

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