Vol 486, No 1 (2019)

Mathematics
On the classification of stably reflective hyperbolic Z[√2]-lattices of rank 4
Bogachev N.V.
Abstract

In this paper we prove that the fundamental polyhedron of a 2-arithmetic reflection group in the three-dimensional Lobachevsky space contains an edge such that the distance between its framing faces is small enough. Using this fact we obtain a classification of stably reflective hyperbolic 2-lattices of rank 4.

Доклады Академии наук. 2019;486(1):7-11
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Homogenization limit for the Diffusion Equation in a domain Perforated along (n - 1)-Dimensional Manifold with Dynamic Conditions on the Boundary of the Perforations: Critical Case
Zubova M.N., Shaposhnikova T.A.
Abstract

The problem of homogenization the diffusion equation in a domain perforated along an (n - 1)-dimensional manifold with dynamic boundary conditions on the boundary of the perforations is studied. A homogenization model is constructed that is a transmission problem for the diffusion equation with the transmission conditions containing a term with memory. A theorem on the convergence of solutions of the original problem to the solution of the homogenized one is proved.

Доклады Академии наук. 2019;486(1):12-19
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Perron stability and its study at the first approximation
Sergeev I.N.
Abstract

Natural concepts of Perron stability, asymptotic stability, and complete instability of the trivial solution to a differential system are introduced. Their features and relationships with Perron exponents and similar Lyapunov ones are indicated. An absolute and unique coincidence of research opportunities for Perron and Lyapunov stability and asymptotic stability at the first approximation is found.

Доклады Академии наук. 2019;486(1):20-23
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Some properties of ultrafilters of widely understood measurable spaces
Chentsov A.G.
Abstract

Filters and ultrafilters (maximal filters) on the π-system with “zero” and “unit” are considered (here, π-system is a nonempty family of sets closed with respect to finite intersections); so, our π-system contains including and empty sets. Characteristic properties of ultrafilters obtained from special representations for bases of two typical topologies connected with construction of Wallman extension and Stone compactums are investigated. The topology of Wallman type on the ultrafilters set of arbitrary π-system with “zero” and “unit” is defined. In addition, initial set is transformed in a compact T1-space with points in the form of ultrafilters of above-mentioned π-system. Under equipment of the resulting ultrafilter set with two topologies (by sense, Stone and Wallman topologies), bitopological space with comparable topologies is obtained; for this space, the degeneracy (in the sense of coincidence for above-mentioned topologies) and nondegeneracy conditions are indicated. The initial set is immersed in above-mentioned bitopological space as everywhere dense subset. Resulting construction is oriented on application in extensions of abstract attainability problems with constraints of asymptotic character (we keep in mind the possible application of ultrafilters as generalized elements).

Доклады Академии наук. 2019;486(1):24-29
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Physics
Wave mixing in a system of moving coaxial cylinders
Ganiev R.F., Reviznikov D.L., Sukharev T.Y., Ukrainskii L.E.
Abstract

The results of computer simulation of mixing in a system of moving coaxial cylinders are presented. Detailed spatial-temporal pictures of the processes occurring were obtained and the main structures in the flow field were determined. Based on the analysis of the singular points of the vector velocity field of the liquid, a method for profiling the rotor is proposed. Introduced dimensionless quantities, the use of which allows the transition from laboratory bench installations to real production devices.

Доклады Академии наук. 2019;486(1):30-33
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Transverse deformation and nonlinearity of force interactional interaction of solids
Sanditov D.S.
Abstract

At this stage, it is necessary to allow the dependence of the Poisson coefficient (parameter of elasticity theory) on the nonlinearity of the interatomic interaction force and the anharmonicity of lattice vibrations (Gruneisen parameter). This dependence follows from the experimental data and finds justification in the framework of the existing theoretical developments, primarily the BRB model (Berlin-Rothenburg-Baserst). The relationship between the linear (harmonic) and nonlinear (anharmonic) properties of solids is discussed using the example of the unambiguous connection of the Poisson coefficient μ with the Gruneisen parameter.

Доклады Академии наук. 2019;486(1):34-38
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Technical Physics
The fractal model of reinforcement of nanocomposites polymer/carbon nanotubes with ultrasmall concentrations of nanofiller
Kozlov G.V., Dolbin I.V., Koifman O.I.
Abstract

The structural aspects, defining reinforcement degree (enhancement of elasticity modulus) of nanocomposites polymer/carbon nanotubes with ultrasmall concentrations of nanofiller, were considered. It has been shown that the indicated parameter is controlled by two factors, namely, structure of nanocomposite and type of reinforcing component. Introduction of nanofiller in matrix polymer changes its structure in virtue of formation of interfacial regions. Hence, the efficiency of nanofiller as reinforcing element is defined by its ability to generate interfacial regions.

Доклады Академии наук. 2019;486(1):39-43
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Analysis of the crystallogeometry of tetragonal martensite in indium-cadmium alloys by the method of electron back scattering diffractions
Schastlivtsev V.M., Khlebnikova Y.V., Rodionov D.P., Egorova L.Y.
Abstract

It was shown in the work using electron back scattering diffractions analysis that when cooling lower than temperature of the martensitic fcc-hct transformation in the alloy In - 4.5 wt% Cd a packet structure is formed consisting of colonies of tetragonal lamella plates. At the next packages there are always three grades of the plates of a tetragonal martensite which are in twinning situation and differing with the direction of the tetragonality axis. Each martensitic plate consists in turn of a set of more shallow submicrotwinning plates alternating in the direction of an axis of tetragonality. On the basis of the obtained data it is possible to conclude that the structure of the package consisting of twinning plates and the structure of the separate martensitic plate consisting, in turn, of submicro-twins submits to the general regularities. At each structural level in group of the neighboring areas the building blocks of three grades differing with the direction of a tetragonality axis are found.

Доклады Академии наук. 2019;486(1):44-48
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Chemistry
A new approach to obtaining carboranylmethylsiloxanes
Izmaylov B.A., Vasnev V.V., Markova G.D.
Abstract

The efficient method for the synthesis of o(m)-carboranylmethylsiloxanesby the Grignard reaction based on 1,2 (7)-bis(bromomagnesiummethyl)-o(m)-carboranes and 1-chloro-1,1,3,3,3-pentamethyldisiloxane was developed. As a result, 1-(1,1,3,3,3-pentamethyldisiloxanylmethyl)-2(7)-methyl-o(m)-carboranes, 1,2(7)-bis(1,1,3.3,3-pentamethyldisiloxanylmethyl)-o(m)-carboranes, exocyclic 1,2-(o-carborano)-4,6-bis(dimethylsilyl)-5-oxa-cycloheptane, 1,7-bis(chloro-1,1,3,3-tetramethyldisiloxanylmethyl)-m-carborane and the oligomer containing two 1,7-bis(dimethylsilylmethyl)-m-carborane units were obtained.

Доклады Академии наук. 2019;486(1):49-52
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Sources of paleomagnetic signal in iron-bearing marine sedimentary deposits
Rudmin M.A., Mazurov A.K., Sergienko V.I., Savichev O.G., Semiletov I.P.
Abstract

This paper presents the results of interpreting the change in the magnetic signal of ferruginous marine sedimentary rocks using the example of the Cretaceous-Paleogene Bakchar deposit (Western Siberia). Anomalous magnetic susceptibility (MS) values are determined by two factors: (a) a diagenetic process accompanied by the formation of pyrrhotite, greigite and siderite in ironstones, (b) an increase detrital input with deposition of magnetite and ilmenite in the siltstones on the background of climate moistening and intense weathering. It is shown that increased MS values in iron-bearing marine sedimentary deposits can be associated with the formation of ferrimagnetic sulfides, which indicates to the methane emission through ancient marine bottom sediments.

Доклады Академии наук. 2019;486(1):53-56
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Chemical Technology
The influence of sodium niobate addition on sintering and properties of zirconia ceramics
Smirnov V.V., Smirnov S.V., Obolkina T.O., Goldberg M.A., Antonova O.S., Barinov S.M.
Abstract

The study of sintering, microstructure and phase composition of zirconia ceramics containing the additive - sodium niobate. It is shown that the use of an additive helps to reduce the sintering temperature to 1,400 ° C. The obtained materials are characterized by a high content of the tetragonal phase, a fine-crystalline structure and high strength up to 440 MPa during bending. The developed low-temperature materials can be used in dentistry as ceramic crowns.

Доклады Академии наук. 2019;486(1):57-60
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Physical chemistry
Voltammetric analysis in blood serum in patients with severe combined trauma
Tsivadze А.Y., Petrikov S.S., Goroncharovskaya I.V., Evseev А.K., Shabanov A.K., Batishchev O.V., Andreev V.N., Goldin M.M.
Abstract

Voltammetric analysis of antioxidant activity of blood serum in patients with severe combined trauma showed differences in favorable and adverse outcome groups. Based on the experimental data a criterion for assessing risk of adverse outcome in critically ill patients is proposed.

Доклады Академии наук. 2019;486(1):61-64
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Geology
Influence of asphaltenes on wettability of gas and oil saturated reservoir rock
Mikhailov N.N., Ermilov O.M., Sechina L.S.
Abstract

The wettability of terrigenous and carbonate rock cores of oil and gas condensate fields extracted with n-hexane and chloroform by asphaltenes was studied. The obtained values of core wettability with asphaltenes show their contribution to the change of wettability of different rocks.

Доклады Академии наук. 2019;486(1):65-68
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Specific features of supercontinent cycles in the metallogeny of tantalum
Tkachev A.V., Rundqvist D.V., Vishnevskaya N.A.
Abstract

The metallogeny of tantalum through the geological history has been analyzed. A representative sampling contains mineral deposits of five types: pegmatitic, granitic, alkaligranitic, foidic, and carbonatitic ones. They were formed with a variable intensity during the time range from the Late Mesoarchean to Cenozoic. The most notable resources of tantalum are known in the deposits of the Rodinian cycle, as well as the Pangean and Colombian ones. All these cycles stand out against other ones by a leading role of the deposits associated with alkaline magmas of mantle origin. However, the concentrates of the highest quality to extract tantalum are obtained from the deposits in rare-metal pegmatites and lithium-fluorine granites produced by crustal magmas. Only the pegmatitic deposits are known for the Kenoran cycle in tantalum metallogeny. They contain a maximum amount of such high-quality resources.

Доклады Академии наук. 2019;486(1):69-73
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Geodynamic position of large and super large precious metal and uranium ore districts and nodes in the East Asia
Khomich V.G., Boriskina N.G.
Abstract

The analysis results of the geophysical, seismic tomography and mineragenic data are presented, revealing the prerequisites for the regular of the location large and unique precious metals and uranium ore nodes of Southeast Russia, East Mongolia and Northern China. Shown that probable causes localization of the world-class ore clusters and districts above a stagnant oceanic slab perimeter are predetermined by concentration of the lower mantle fluid-heat fluxes at the frontal part of the slab and on its flanks, which are represented by sublatitudinal paleotransformal faults.

Доклады Академии наук. 2019;486(1):74-77
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Deep xenolith of platinum-bearing websterite from paleoproterozoic Volchetundra gabbro-anorthosite massif in the Kola region
Chashchin V.V., Savchenko Y.E., Lyulko M.S.
Abstract

The results of studies of the deep platinum-bearing xenolith found in the Volchetundra gabbro-anorthosite massif of the Kola region are presented. It is shown that xenolith with a size of 8.5 × 4 m is composed of websterite in the central part and plagiowebsterite in the marginal. The chemical and mineral composition of xenolith rocks was studied. Information is given on the contents of noble and chalcophile elements in them, as well as the composition of platinum group minerals.

Доклады Академии наук. 2019;486(1):78-82
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Geochemistry
New data on fiedlerite-1A from ancient slags of Lavrion, Greece: crystal structure and H-bonding
Zubkova N.V., Chukanov N.V., Pekov I.V., Pushcharovsky D.Y., Katerinopoulos A., Voudouris P., Magganas A.
Abstract

The crystal structure (R = 0.0750) of fiedlerite-1A Pb3Cl4F(OH) H2O from ancient slags of Lavrion (Greece) was studied on a single crystal. The mineral is triclinic, a = 8.5741(7), b = 8.0480(5), с = 7.2695(4) Å, (a = 90.087(5), (b = 102.126(6), (g = 103.424(6)) V = 476.37(6) Å3, Z = 2. Pb2+ cations centre bicapped trigonal prisms Pb(1)F(H2O)Cl6, Pb(2)(OH)2FCl5 and Pb(3)(OH)F2Cl5. Additional Pb′site with 10% occupancy was revealed in the structure. There are two basic structure fragments alternating along the a axis: (100) layers formed by Pb(2)- and Pb(3)-centred polyhedra and elongated along the b axis zig-zag chains formed by Pb(1)-centred polyhedra sharing common edges. IR spectrum of fiedlerite-1A is given.

Доклады Академии наук. 2019;486(1):83-87
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On time of the triassic rifts system origin in West Siberia
Ivanov K.S., Erokhin Y.V.
Abstract

It is commonly supposed that a very substantial volume of early basalt magmatism effused synchronously on Siberia platform and West Siberia in a very short time interval at 249.4 ± 0.5 Ma (Reichow et al., 2002, etc.). This magmatism and induced climate change are considered as a main reason of the most catastrophic in the Earth history extinction at the border of Permian and Triassic time. But these conclusions were based on incomplete and unrepresentative data on West Siberia. We have obtained by analysis of pyroxenes monofraction from kainotype basalts of Guslinskaya P-430 well Ar-Ar age 268.4 ± 7.5 Ma. In Taurovskaya 503 well this age is 268.1 ± 7.5 Ma. Hence, volcanism in axial rift zones of the basement of West Siberia plate began earlier than that considered before and significantly earlier than on Siberia platform.

Доклады Академии наук. 2019;486(1):88-92
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Water in parental basaltic magmasof the Menshiy Brat volcano (Iturup Island, Kurile islands)
Nizametdinov I.R., Kuzmin D.V., Smirnov S.Z., Rybin A.V., Kulakov I.Y.
Abstract

The paper presents study of the liquidus assemblage of olivine and spinel in high-magnesian basalts (MgO up to 10 mas. %) of the Menshiy Brat volcano (Iturup Island). It was possible to reconstruct the water content and evolution of volatile components in the primary parental magmas that took part in the formation of the Medvezhya Caldera, Iturup Islands. It is shown that the initial water content in the primary melts could reach 5 mas. % with oxygen fugacity corresponding to oxygen buffer NNO + 0.4 log. units. The evolution of magmas involved continuous degassing while magma rises to the surface. The water-rich fluid, which is constantly separated by evolving magma, could play a significant role in the formation of large siliceous magma chambers, which participated in catastrophic caldera eruptions.

Доклады Академии наук. 2019;486(1):93-97
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The geochemical characteristics of the Jurassic plume magmatism within Ahlmannryggen massif (Queen Maud Land, East Antarctica)
Sushchevskaya N.M., Belyatsky B.V., Leitchenkov G.L., Batanova V.G., Sobolev A.V.
Abstract

Mesozoic dikes associated with the Karoo plume were studied within the East Antarctica where at Queen Maud Land on the Almannryggen massif high-Ti magnesian Fe-basalts were found. It is assumed that such basalts originate by means of the pyroxenite-containing mantle melting. The isotopic characteristics of the studied dolerites reflect the composition of the pyroxenite source - the ancient oceanic lithosphere (ЕМI), submerged at the mantle depths of 150-170 km in the paleosubduction zone of the Gondwanian continent and transformed 180 m.y. ago into the pyroxenite melt when interacting with the plume mantle peridotite.

Доклады Академии наук. 2019;486(1):98-102
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Oceanology
About the methane flux into the atmosphere in the South-China sea
Shakirov R.B., Yatsuk A.V., Mishukova G.I., Obzhirov A.I., Yugai I.G., Lan N., Cuong D.
Abstract

The new results of gasgeochemical studies in the integrated expedition of the Russian Academy of Sciences on R/V “Akademik Boris Petrov” (Cruise 42) along the regional profile (3180 km) in the South China Sea (Bien Dong) from January 10-16, 2017 are presented. The expedition conducted in the frame of the Second International Indian Ocean Expedition (IIOE-2). For the first time, five zones of increased methane fluxes were detected. Zones with maximum values of methane fluxes correlate well with the location of hydrocarbon deposits and tectonic faults.

Доклады Академии наук. 2019;486(1):103-107
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Biochemistry, biophysics, molecular biology
Cytokinins and Abscisic Acid Regulate the Expression of the Genes for Plastid Transcription Apparatus during Heat Shock
Andreeva A.A., Bychkov I.A., Danilova M.N., Kudryakova N.V., Kusnetsov V.V.
Abstract

The treatment of Arabidopsis thaliana plants with exogenous cytokinin (CK) followed by heat shock (HS) activated the expression of the genes for the plastid transcription machinery but adversely affected the plant viability. Abscisic acid (ABA), conversely, promoted maintaining the resistance to HS and had differentially affected different components of the plastid transcriptional complex. This hormone suppressed the accumulation of transcripts of PEP genes and the genes encoding PAP proteins, which are involved in DNA-RNA metabolism. However, it had no effect or activated the expression of NEP genes and PAP genes, which are involved in the redox regulation, as well as the genes encoding the stress-inducible trans-factor (SIG5) and the plastid transcription Ser/Thr protein kinase (spCK2). Thus, for the adaptation of plants to elevated temperatures, both increase and decrease in the expression of the genes for the plastid transcriptional machinery with the involvement of various regulatory systems, including phytohormones, are equally significant.

Доклады Академии наук. 2019;486(1):108-113
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Synuclein deficiency decreases the efficiency of dopamine uptake by synaptic vesicles
Ninkina N.N., Tarasova T.V., Chaprov K.D., Goloborshcheva V.V., Bachurin S.O., Buchman V.L.
Abstract

In the present study we analyzed uptake of radiolabeled dopamine by intact synaptosomes and purified synaptic vesicles isolated from the dorsal striatum of mice with constitutive inactivation of all three synuclein-coding genes and wild type mice. Synuclein deficiency substantially compromised the uptake of this neurotransmitter by synaptic vesicles whereas had no effect on synaptosomal dopamine uptake.

Доклады Академии наук. 2019;486(1):114-117
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Estimation of metabolism of catecholamines in peripheral organs as an indicator of their desympathization under the influence of neurotoxins
Safandeev V.V., Kolacheva A.A., Ugrumov M.V.
Abstract

On the preclinical (early) and clinical stages of experimental model of Parkinson’s disease after administration of 1-methyl-4-phenyl-1,2,3-6-tetrahydropyridine (MPTP) neurotoxin to mice during 5 and 10 weeks was evaluated the toxic effect of MPTP, i.e. the catecholaminesand their metabolites content’s in the heart, receiving the most extensive sympathetic innervation. The obtained data testified to the beginning of the desimpathization of the heart at the preclinical stage of PD and its progression at the clinical stage of the disease.

Доклады Академии наук. 2019;486(1):118-122
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Cell biology
The adhesion of human dermal fibroblasts on anodized nanotube-layered titanium, modified for implantology application
Fadeyev F.A., Khrunyk Y.Y., Belikov S.V., Lugovets D.V., Gubaeva O.V., Karabanalov M.S., Leontyev S.L., Popov А.А.
Abstract

Anodization of titanium implants is accompanied by the formation of titanium oxide nanotubes improving osseointegration. An excessive fibroblast adhesion on the surface might lead to the formation of fibrous capsule resulting in implant rejection. In our research, we demonstrated that the adhesion activity of human dermal fibroblasts on anodized surface was not elevated, which is promising for the use of titanium with nanotube-layered surface for implantology.

Доклады Академии наук. 2019;486(1):123-126
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General biology
Siboglinids (Annelida, Siboglinidae) as possible indicators of carbohydrates on the case of the Sea of Okhotsk
Karaseva N.P., Gantsevich M.M., Obzhirov A.I., Shakirov R.B., Starovoytov A.V., Smirnov R.V., Malakhov V.V.
Abstract

Siboglinids (Annelida, Siboglinidae) as possible indicators of carbohydrates on the case of the Sea of Okhotsk Geographical and bathymetric distribution of siboglinides in the sea of Okhotsk was studied. More than 75% of all siboglinides were found at a depth of 400 m. These findings were mainly concentrated in the North-Western part of the shelf. A comparison of the distribution of siboglinides in the Sea of Okhotsk and generalized geological data on the distribution of hydrocarbons showed that siboglinides in the sea of Okhotsk were mostly found in the areas of hydrocarbon manifestations and were absent in the central regions, where in the bottom sediments and in the near-surface layer of water we have registered minimal methane and hydrocarbon concentrations.

Доклады Академии наук. 2019;486(1):127-130
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The provisional dermal folds in the mouth apparatus of the American paddlefish Polyodon spathula Walbaum, 1858 (Acipenseriformes, Polyodontidae)
Tsessarsky A.A.
Abstract

The transitory dermal infoldings are described for the first time in front and behind the upper jaw in the larvae and postlarvae of the American paddlefish, Polyodonspathula Walbaum, 1858. In sturgeons these infoldings are necessary for the jaw protraction. In the paddlefishes, they, probably recapitulate the ancestral state. At the same time, the presence of these folds at the larval stages might indicate that the paddlefish larvae possess the protractive jaws. Further developmental studies of the jaw kinematics in Polyodonspathula are needed to test both hypotheses.

Доклады Академии наук. 2019;486(1):131-134
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