Vol 488, No 1 (2019)

Mathematics
Quantum graphs with summable matrix potentials
Granovskyi Y.I., Malamud M.M., Neidhardt H.
Abstract

Let G be a metric, finite, noncompact, and connected graph with finitely many edges and vertices. Assume also that the length at least of one of the edges is infinite. The main object of the paper is Hamiltonian Hα associated in L2(G; Cm) with matrix Sturm-Liouville’s expression and boundary delta-type conditions at each vertex. Assuming that the potential matrix is summable and applying technique of boundary triplets and the corresponding Weyl functions we show that the singular continuous spectrum of the Hamiltonian Hα as well as any other self-adjoint realization of the Sturm-Liouville expression is empty. We also indicate conditions on the graph ensuring the positive part of the Hamiltonian Hα to be purely absolutely continuous. Under an additional condition on the potential matrix the Bargmann type estimate for the number of the negative eigenvalues of the operator Hα is obtained. Also we find a formula for the scattering matrix of the pair {Hα, HD} where HD is the operator of the Dirichlet problem on the graph.

Доклады Академии наук. 2019;488(1):5-10
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A neural network construction for pattern recognition problems with standard information on the basis of the algorithms of model with piecewise linear surfaces and parameters
Zhuravlev Y.I., Dyusembaev A.E.
Abstract

In the paper for recognition problems with standard information on the basis of the operator approach and the model with parameters and piecewise linear surface has been constructed a neural network which reproduced of computations performs by the correct algorithm.

Доклады Академии наук. 2019;488(1):11-15
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On the complexity of some partition problems of a finite set of points in Euclidean space into balanced clusters
Kel’manov A.V., Pyatkin A.V., Khandeev V.I.
Abstract

We consider some problems of partitioning a finite set of N points in d-dimension Euclidean space into two clusters balancing the value of (1) the quadratic variance normalized by a cluster size, (2) the quadratic variance, and (3) the size-weighted quadratic variance. We have proved the NP-completeness of all these problems.

Доклады Академии наук. 2019;488(1):16-20
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Cross-entropy optimal dimensionality reduction with condition on information capacity
Popkov Y.S., Popkov A.Y.
Abstract

Using a data leads to a problem of its sufficiency to solve specific task. Proposed paper is devoted to a modification of direct-inverse projection method (DIP-method) based on an idea of information capacity. DIP-method is updated with a condition on maintaining the information capacity in given ranges. Modified dimensionality reduction method (mDIP) based on the problem of minimization cross-entropy function on a set defined by linear inequality. Minimization of the function is suggested to perform by the first-order multiplicative algorithm. There obtained conditions of local convergence.

Доклады Академии наук. 2019;488(1):21-23
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Theoretical physics
Structural-induced lubricity of liquid crystal nanomaterials of cholesterol at metal friction
Kolesnikov V.I., Ermakov S.F., Shershnev E.B., Sychev A.P.
Abstract

Experimentally, it was found that with the change in temperature there is a structural-induced increase in the lubricating capacity of liquid-crystal nanomaterials induced by transformations in the cholesteric mesophase. It is shown that in this temperature range, the minimum values of the friction coefficient practically coincide with the peak values of the dynamic viscosity, which together indicates in favor of the ordered state of the cholesterol liquid-crystal structures at these temperatures. As a result, it can be assumed that in this temperature range, spirally twisted layers of liquid-crystal cholesterol molecules with high antifriction action are formed in the friction zone. It is noted that the thickness of the friction-implemented cholesteric liquid-crystal films is sensitive to temperature changes in the contact area, changing the color and energy loss.

Доклады Академии наук. 2019;488(1):24-28
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Mechanics
Aeroelastic stability of a cylindrical shell of linearly varying thickness
Bakulin V.N., Konopelchev M.A., Nedbay A.Y.
Abstract

For the first time, the aeroelastic stability equations of a composite cylindrical shell of linearly varying thickness are obtained on the basis of the bending theory of orthotropic shells for a shell subjected to axial forces and supersonic gas flow. The solution of the equations is assumed of the form of a trigonometric series in the axial coordinate. The problem is reduced to an infinite system of algebraic equations by the Bubnov-Galerkin method. The obtained characteristic equation is approximated by the Lagrange polynomial, whose stability is investigated with the use of the Routh-Hurwitz criterion. As a numerical example, the effect of the thickness gradient, structural damping and axial force on the critical velocity for a composite shell of linearly varying thickness in supersonic gas flow is shown. The refinement in the value of the critical velocity resulting from the use of the suggested model is about 35% as compared to the results for a shell of averaged constant thickness. This indicates the relevance of this model for aircraft weight optimization. The suggested approach expands the range of problems to be solved and allows for the analysis of the aeroelastic stability for orthotropic cylindrical shells of linearly varying thickness in supersonic gas flow.

Доклады Академии наук. 2019;488(1):29-35
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Chemical Technology
Sintering and properties of dioxide of ceramics containing the sodium silicate additive
Smirnov V.V., Smirnov S.V., Obolkina T.O., Antonova O.S., Goldberg M.A., Khairutdinova D.R., Ovchinnikova O.A., Barinov S.M.
Abstract

The dependences of the formation of the microstructure and the phase composition of ceramics based on partially stabilized zirconium dioxide on the sintering temperature and the content of the sintering additive are established. It is shown that the introduction of an additive, which forms a low-temperature melt based on sodium silicate - Na2SiO3, leads to a decrease in the sintering temperature by 200 °C. As a result of the work, were obtained dense nanocrystalline materials with a crystal size of 100-200 nm, flexural strength up to 600 MPa and a sintering temperature of 1200-1250 °C. 

Доклады Академии наук. 2019;488(1):36-39
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Physical chemistry
Changes in the mechanical properties of powdered aluminum matrix composites modified with micro additive hybrid materials based on multi-walled carbon nanotubes decorated with titanium carbide nanoparticles
Aborkin A.V., Babin D.M., Zalesnov A.I., Ob`yedkov A.M., Kremlev K.V., Alymov M.I.
Abstract

The method of powder metallurgy produced bulk composite materials based on aluminum alloy AMg2, strengthened with 0.05 wt.% MWCNT and MWCNT, decorated with TiC nanoparticles. The results of a comparative analysis of the structure-phase composition and properties of powder composites are presented. It has been established that the use of MWCNT-hybrid filler contributes to an increase in the conditional yield strength during compression of a composite material compared with an aluminum-matrix composite filled with MWCNT.

Доклады Академии наук. 2019;488(1):40-43
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Debonding of metal coating of a track-etched membrane
Bazhenov S.L., Razumovskaya I.V., Kovalets N.P., Bedin S.A.
Abstract

Behavior of metallic nano-coating of the track membrane based on polyethylene terephthalate film under tension was investigated. In the vicinity of cracks in the coating, conical-shaped debondings of the coatings were observed. Debondings have the form of sharp cones, elongated along the tension axis and perpendicular to the cracks. Nanopores initiate multiple cracking of the coating, and the cracks initiate local debondings. Short microcracks mutually suppress their growth. As a result, long cracks crossing the entire coating do not appear. As a result, the coating retains its continuity and conducts electric current.

Доклады Академии наук. 2019;488(1):44-46
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Physical chemistry CeF4 complexes in organic solvents
Il`in E.G., Parshakov A.S., Yarzhemsky V.G., Ugolkova E.A., Goyeva L.V., Privalov V.I.
Abstract

The first complexes of cerium tetrafluoride in solutions were investigated by 19F NMR and IR spectroscopy. The temperature dependence of the 19F NMR spectra was, studied and it was concluded that mobile equilibrium exists between the molecular adduct and singly charged ionic forms, including geometric isomers. The static probability of stereoisomer formation [CeF4(dmso)4] was calculated using the square antiprism configuration and, based on the relative intensity of the 19F NMR resonance signals, they were assigned to possible stereoisomers. Quantum-chemical calculations of the structure of the isomer [CeF4(dmso)4], the isomer [CeF3(dmso)5]+ and [CeF5(dmso)3]-, showing their thermodynamic stability, were performed.

Доклады Академии наук. 2019;488(1):47-51
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Geology
Rb-Sr age of the riphean glauconites of the Kamov group (Baikit anteklise, Siberian platform)
Zaitseva T.S., Kuznetsov A.B., Ivanova N.A., Maslennikov M.A., Pustylnikova V.V., Turchenko T.L., Nаgovitsyn K.E.
Abstract

A mineralogical and geochemical study was conducted and the Rb-Sr age of globular layered silicates (GPS) of the glauconite-illite series of the Dolgokta Formation from a parametric Chunkinskaya-282 drillcore was determined. The assessment of suitability of the mineral for geochronological purposes took into account the data of Mössbauer spectroscopy and modeling of the cation distribution in the GPS octahedral net. Mineralogical and crystalochemical characteristics indicate an epigenetic alteration of glauconite structure; therefore, its Rb-Sr isochronous age (1300 ± 7 Ma) is “rejuvenated” and reflects the stage of partial recrystallization. The 87Sr/86Sr ratio in dolomites of the Dolgokta and Kuyumba formations varies from 0.70602 to 0.72230, which confirms the epigenetic recrystallization. The model Rb-Sr age of glauconite, calculated taking into account the enrichment of radiogenic 87Sr, is within 1340-1400 Ma. The age estimate determines the upper limit of distribution of the Mesoproterozoic fossil Tappania, found in the Yurubchen and Dolgokta formations of the Baikit anteclise.

Доклады Академии наук. 2019;488(1):52-57
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Sm-Nd age of picrites of the Lysogorsk complex (Southern Urals): evidence of initial middle riphean magmatism
Kovalev S.G., Maslov A.V., Kovalev S.S., Vysotsky S.I.
Abstract

The article presents new data on the age of the picrites of the Lysogorsk complex, common in the Taratash metamorphic complex (Bashkir meganticlinorium, western slope of the Southern Urals). Based on Sm-Nd dating (1409 ± 89 Ma) and calculated data on the crystallization pressure and temperature of mineral parageneses, it is concluded that picrites belong to the initial type of magmatism, which characterizes the initial stages of the Mashak magmatic event.

Доклады Академии наук. 2019;488(1):58-61
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Early mesozoic alkaline magmatism of the western framing of the Mongol-Okhotsk belt: age and structural position
Yarmolyuk V.V., Kozlovsky A.M., Sal`nikova E.B., Eenzhin G.
Abstract

A zonal igneous area appeared at the western end of the Mongol-Okhotsk belt in the early Mesozoic. Its central part forms a giant Khentey-Dauria batholith, which from the north and west is framed by rift-like structures with bimodal and alkaline granite magmatism. The geochronological studies of the peralkaline granites of the Choyr and Gal-Shara massifs were carried out. These massifs belong to the North Gobi (southern) border of the batholith. The age of the first was 215 million years, the age of the second was 213 million years. It is shown that associations involving alkaline igneous rocks are fairly well developed in the North Gobi zone. They are controlled by faults and grabens of the northeast strike. Thus, it was established that the formation of the zonal magmatic area was characterized by a specific mode. In its central part, which corresponds to the zone of the Mongol-Okhotsk suture, anatexis and batholite formation processes took place, and the periphery was involved in the processes of rifting. The data obtained indicate the closure of the western part of the Mongol-Okhotsk trough before the formation of the zonal magmatic area. The structure of the magmatic area was determined by the mechanisms of the plume-lithospheric interaction in the region characterized by a collision suture (anatectic melting zone) and its less tektonic tense framing (rifting zones).

Доклады Академии наук. 2019;488(1):62-66
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Geochemistry
Sources of matter for Neoarchaean subalkaline magmatic rocks of the Keivy structure (Kola Peninsula)
Vetrin V.R.
Abstract

The Neoarchaean subalkaline magmatism of Keivy structure is expressed in formation of the volcano-plutonic association of latite-monzonite-granite (ALMG). The quantity of the measured relation 143Nd/144Nd in rocks is determined in 0.511061-0.511365, and values of model age are located in an interval from 3.14 to 3.21 billion years at εNd (2670) from 2.2 to -1.3. The initial relations 176Hf/177Hf in zircon are in limits 0.280950-0.281069, and figurative points of composition form the field around a trend of the CHUR. According to the isotope and geochemical data for all rocks the basic composition of protholits is supposed. In quantity εHf(T) points of zircon are localized in the field of the development of the crust with 176Lu/177Hf = 0.015 and 3.0-3.3 billion years age. It probably demonstrates the formation of initial melts mainly at the expense of matrix with a long time of stay in crust. The formation of ALMG magmas is assumed to appear due to the melting of metasomatically altered rocks of the lower crust during intrusion of basaltic melts initial for the rocks of the dike complex and the gabbro-labradorite massifs into the upper crust.

Доклады Академии наук. 2019;488(1):67-70
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Characteristic of rare-earth element distributions in mud volcanic waters
Ershov V.V., Elovskiy E.V., Puzich I.N.
Abstract

The original results on the distribution of rare-earth elements in the waters of mud volcanoes in Sakhalin Island, Taman Peninsula and Azerbaijan are presented. It has been shown that mud volcanic waters with total content of rare-earth elements less than 0.5 mcg/l are enriched with heavy lanthanides and characterized by a deficiency for Cerium. The Yuzhno-Sakhalinsk mud volcano demonstrates higher rare-earth element content in active griffons according to our study.

Доклады Академии наук. 2019;488(1):71-73
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Geophysics
Contribution of natural and anthropogenic emissions of CO2 and CH4 to the atmosphere from the territory of Russia to global climate change in the 21st century
Denisov S.N., Eliseev A.V., Mokhov I.I.
Abstract

Obtained the estimates of the contribution of anthropogenic and natural GHG emissions into the atmosphere from the territory of Russia to global climate change under various scenarios of anthropogenic impact in the 21st century. Accounting for changes in climatic conditions can strongly influence the indicators of the impact of various greenhouse gas emissions on the climate system, especially at large time horizons. Moreover, depending on the planning horizon, the role of the natural fluxes of greenhouse gases into the atmosphere from terrestrial ecosystems may change. Currently, terrestrial ecosystems in the Russian regions affect global temperature in both directions: absorbing CO2 from the atmosphere contributes to slowing its growth, and emitting CH4 into the atmosphere accelerates warming. The net effect of the natural fluxes of these greenhouse gases from the Russian regions in modern conditions helps to slow down warming. This net effect is increasing in the first half of the 21st century, and after reaching a maximum (depending on the anthropogenic emission scenario) decreases by the end of the century under all the considered anthropogenic impact scenarios due to an increase in natural CH4 emissions and a decrease in CO2 absorption by terrestrial ecosystems.

Доклады Академии наук. 2019;488(1):74-80
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Conjugacy problem for stationary heat fields
Ladovsky I.V., Martyshko P.S., Byzov D.D., Tsidaev A.G.
Abstract

Analytic solution for thermal conjugation stationary problem is obtained for the model of layered inhomogeneous media. Heat flux components for crust and mantle are selected. Recalculation of mantle component of flux down to the mantle top was performed, the results compared with relief of deep structures.

Доклады Академии наук. 2019;488(1):81-85
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Geography
New data of vegetation development of North Baikal area in the Middle-Late Holocene
Vershinin K.E., Osipov E.Y.
Abstract

For the first time, a continuous section of peat was obtained from the hard-to-reach mid-mountain North-Western part of the lake Baikal. The material was studied by methods of spore-pollen analysis, analysis of plant cell residues and radiocarbon Dating (data calibrated). The least identified in the Holocene speed of peat accumulation in the Baikal area. According to the calculated sedimentation rates, the temporal resolution of the study ranges from 100 years at the bottom of the incision to 800 years at the top. With a factor analysis identified six local pallinson and five Botanic zones. Changes in the vegetation cover and ecotope moisture conditions for 7670 years were reconstructed. For the first time in a quarter of a century, the height of the upper forest boundary has been clarified.

Доклады Академии наук. 2019;488(1):86-90
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Holocene methane emissions in the South-Western part of the Okhotsk Sea (on the basic of carbon isotopes in the tests of benthic foraminifera)
Pletnev S.P., Romanova A.V., Wu Y., Annin V.K., Utkin I.V., Vereshchagina О.F.
Abstract

We report several negative carbon stable isotope excursions in benthic foraminifera in a gas-bearing core LV50-05, collected from an area of active methane venting on the Eastern Slope of Sakhalin Island, the Okhotsk Sea. Within the study area, four methane events (ME) are established in Holocene: short-term ME-1 (700-900 yr BP) and ME-2 (from 1200 to 1400 yr BP), long-term ME-3 (2500-4700 yr BP) and ME-4 (7400-10000 yr BP).

Доклады Академии наук. 2019;488(1):91-93
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Oceanology
Methodology of directional development of local biocenoses for optimization of monitoring and improvement of the marine environment on shelves of Russia
Ushivtsev V.B., Vostokov S.V., Lobkovsky L.I., Vodovsky N.B., Galaktionova M.L.
Abstract

The results of field experiments on the development of local biocenoses based on bottom bio-stations situated in areas with high anthropogenic influence in the Northern and Middle Caspian region are presented. Structural and functional parameters of local communities were studied in comparison with characteristics of background biocenoses. Biodiversity and informational content of local communities as objects of monitoring and bio indication was assessed. The application of the bottom biocenosis directed development on artificial substrates for monitoring and improvement of the marine environment are discussed.

Доклады Академии наук. 2019;488(1):94-98
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Biochemistry, biophysics, molecular biology
Activation of Su(Hw) controlled genes is associated with increase in GAF binding
Elizar`ev P.V., Chetverina D.A., Melnikova L.S., Srivastava A., Mishra R.K., Golovnin A.K., Georgiev P.G., Erokhin M.M.
Abstract

The interaction of the GAF protein with the promoters of neuron-specific genes during activation and repression of transcription has been studied. We have shown that while the Su(Hw) protein remains stably associated with the promoters of these genes at different transcriptional state, the GAF protein level is significantly higher when transcription is activated.

Доклады Академии наук. 2019;488(1):99-102
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The antiproliferative action of the “early” protein of papillomavirus HPV16 E2 on testis toumors of mice induced by the injection of Hela cells
Salyaev R.K., Rekoslavskaya N.I., Stolbikov A.S.
Abstract

The аntiploliferative effect of the “early” protein of high-risk oncogenic human papillomavirus HPV16 E2 on mice testis tumors was discovered after the indyction that was happened after the intramuscular injection of cancer HeLa cells suspension. The regression of mice testis tumors was mostly dramatic during first 1-2 days after oral vaccination with HPV16 E2 (500 mg per mice) made in tomato plant expression system that was gradually decreasing to control variant. The typical monolayer of HeLa cells on the cultivation flask bottom was appeared after seeding of testis tissue cells on the DMEM medium they were only for 18% functionally active according to the detection by the staining with nitroblue tetrazolium and trypane blue.

Доклады Академии наук. 2019;488(1):103-107
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Physiology
Combined irradiation by gamma rays and carbon nuclei increases the C/EBP-β LIP-isoform content in the pituitary gland of rats
Anokhina I.P., Anokhin P.K., Kokhan V.S.
Abstract

C/EBP-β, a basic leucine zipper transcription factor, has important roles in the regulation of organism’s immune and inflammatory responses. Wistar rats subjected to the combined irradiation were characterized by an increase in the content of C/EBP-β LIP-isoform in the pituitary gland. The obtained data indicate that moderate doses of ionizing radiation to initiate the endoplasmic reticulum stress response and are likely to initiate C/EBP-β-mediated cell death according to the apoptotic scenario. This study also confirms the earlier hypothesis about the alterations of the hypothalamic-pituitary-adrenocortical axis in response to moderate doses of ionizing radiation.

Доклады Академии наук. 2019;488(1):108-111
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General biology
Responses of aquatic organisms to cyanobacteria and elodea in microcosms
Verbitsky V.B., Kurbatova S.A., Berezina N.A., Korneva L.G., Meteleva N.Y., Makarova O.S., Sharov A.N., Ershov I.Y., Malysheva O.A., Russkikh Y.V., Chernova E.N., Borisovskaya E.V.
Abstract

The aim of the work was to investigate the effect of cyanobacteria and elodea on population characteristics (abundance, biomass, fecundity) and “health” indicators (embryo status, heart rate and thermal resistance) of aquatic invertebrates in microcosms with controlled conditions. In July-August 2018, four treatments with environmental conditions of the coastal zone of the Rybinsk Reservoir during the period of cyanobacterial bloom were modeled. Mass species of plankton (with 80% dominance of large Daphnia longispina) and benthic animals (Unio pictorum, Gmelinoides fasciatus, Asellus aquaticus) and Elodea canadensis were placed in microcosms. In treatments with cyanobacteria, the toxic microcystins-LR were detected (24-53% of the sum of toxins, or 6,6-66,5 µg/l). The cyanobacteria Aphanizomenon flos-aquae, Microcystis aeruginosa and Gloeoitrichia spp. affected the structure of plankton reflecting in a decrease in the amount of green algae and an increase in the abundance of small crustaceans. Under the influence of cyanobacteria, variables of benthic animals differed significantly from control treatment, including a reduced level of thermal resistance of mollusks and amphipods, an increased recovery time of the heart rate after loading (salinity test) in mollusks, a decrease in individual fecundity, and an increase in the frequency of malformations and embryo mortality in amphipods. The presence of elodea enhanced these effects. Thus, the mass development of cyanobacteria and elodea affects the physiological status of sensitive species of aquatic animals, reducing their adaptability to natural stresses and worsening the quality of offspring.

Доклады Академии наук. 2019;488(1):112-116
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