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Uchuskin M.G.,Kuban State University | Molodtsova N.V.,Kuban State University | Abaev V.T.,North Ossetian State University | Trushkov I.V.,Moscow State University | Butin A.V.,Perm State University
Tetrahedron | Year: 2012

A simple and efficient method for the synthesis of 2-(2-acylvinyl)-3-(5- alkyl-2-furyl)indoles by reductive recyclization of bis(5-alkyl-2-furyl)(2- nitroaryl)methanes is reported. This transformation was carried out by heating the substrates with SnCl 2·2H 2O in ethanol. The intermediate nitrosoarene moiety interacted with the furan ring via electrophilic nitrogen attack onto the C(2) position of the furan ring. It was shown that the related bis(5-alkyl-2-thienyl)(2-nitroaryl)methanes under the same reaction conditions failed to undergo the analogous recyclization and were transformed into bis(5-alkyl-2-thienyl)(2-aminoaryl)methanes. © 2012 Elsevier Ltd. All rights reserved.

Abaev V.T.,North Ossetian State University | Plieva A.T.,North Ossetian State University | Chalikidi P.N.,North Ossetian State University | Uchuskin M.G.,Perm State University | And 2 more authors.
Organic Letters | Year: 2014

A straightforward, efficient indole synthesis based on thermolysis of 2-(2-azidobenzyl)furans with attack of the formed nitrene moiety onto the ipso position of furan ring has been developed. The cyclization is accompanied by furan ring opening and affords indoles with a 2-acylvinyl substituent suitable for further modifications. © 2014 American Chemical Society.

Faulks N.R.,Appalachian State University | Kimball L.R.,Appalachian State University | Hidjrati N.,North Ossetian State University | Coffey T.S.,Appalachian State University
Scanning | Year: 2011

Since durable technology emerged between 3.4 and 3.2 million years ago, stone tools served as a major material means that hominins used to survive. Determining how different lithic tools functioned is a principal question in human evolution. The main experimentally based approach to the functional study of lithic technology uses stereo and incident-light microscopy, and is known as the Keeley Method. Although this method has demonstrated success in linking the morphology of microwear traces on flint tools to the function of the tool, there is no agreed upon model of how these microwear polishes form. At the same time, the characterization of these polishes has been a largely qualitative process. Herein, we use the atomic force microscope (AFM) to scan microwear traces on Middle Palaeolithic (Mousterian) tools from Weasel Cave, Russia to show quantitative data and small scale features of microwear polishes interpreted (using the Keeley Method) as due to contact with meat, fresh hide, dry hide, bone, wood, and hafting. These results follow those of to the previous AFM study on the experimental tools, namely that the meat and dry hide polishes are the least developed polishes with smaller changes in roughness and that the bone polish and wood polishes are more highly developed polishes and exhibit larger changes in roughness. Copyright © 2011 Wiley Periodicals, Inc.

Serdyuk O.,Southern Federal University | Butin A.,Kuban State University of Technology | Abaev V.,North Ossetian State University
Journal of Fluorine Chemistry | Year: 2010

In spite of a large number of publications describing the preparation of fluorinated furan derivatives, there is no systematized overview of the methods of their synthesis. In the present work we try to fill this gap and review the main schemes of syntheses of fluorofurans and perfluoroalkylfurans which contain a perfluoroalkyl group in the heterocycle and in the α-position of the carbon chain of substituents in the furan ring. © 2009 Elsevier B.V. All rights reserved.

Kubalova L.M.,North Ossetian State University | Fadeeva V.I.,Moscow State University
Journal of Phase Equilibria and Diffusion | Year: 2012

This work presents the results of a study of Ni 872xMoxB 13 alloys (x = 7, 10 and 14 at.%), which were obtained by mechanical alloying (MA) of elemental powder mixtures in a MAPF-2M highenergy planetary ball mill. The x-ray diffraction analysis and differential scanning calorimetry measurements were used. The single-phase fcc solid solutions of Mo and B in Ni were formed by MA of Ni-Mo-B mixtures of various compositions for 6-8 h. The coherent domain sizes of solid solutions calculated from the x-ray peak widths were 12-14 nm. The exothermic effects on the DSC curves, which corresponded to the phase transformations of supersaturated Ni(Mo,B) solid solutions, were observed during heating of the synthesized alloys. After heating to 700 °C, the alloys contained a fcc Ni(Mo) phase and a metastable hexagonal MoB4 phase. Thermodynamically stable phase composition of Ni80Mo7B 13 and Ni 77Mo 10B 13 alloys, containing three phases: fcc Ni (Mo), Ni 21Mo 2B 6 with cubic lattice and Ni 3B with orthorhombic lattice, was reached after the isothermal annealing at 1000 °C. The ratio between the amounts of these phases in the alloys corresponds to their location in a three-phase area of the Ni-Mo-B equilibrium phase diagram. © ASM International.

Kazaryan M.L.,North Ossetian State University
Telecommunications and Radio Engineering (English translation of Elektrosvyaz and Radiotekhnika) | Year: 2013

The method of digital signal compression by means of spectral transforms, known as zone coding, is considered. The spectrum of the modified discrete Haar transforms in the class of Lipschitzian signals and the mean-root square error of recovery in the class are evaluated. © 2013 by Begell House, Inc.

Kubalova L.M.,North Ossetian State University | Fadeeva V.I.,Moscow State University
Journal of Alloys and Compounds | Year: 2014

The effect of rotary-shear deformation during powders compacting on the decomposition of supersaturated Ni(Nb,B) and Ni(Mo,B) solid solutions is studied. The metastable fcc solid solutions were synthesized by mechanical alloying (MA) of the mixtures of components of Ni75Nb 12B13 and Ni73Mo14B13 compositions. The powders were compacted on a Bridgman anvil. Col plastic deformation action is realized by using this technique. As a result the initial structure of nonequilibrium supersaturated solid solutions changed. The data of X-ray diffraction analysis and scanning electron microscopy showed a partial decomposition of Ni(Nb,B) and Ni(Mo,B) solid solutions, which leads to the formation of cubic boride τ phases - Ni21Nb2B 6 with a lattice parameter of a = 1.0572 nm and, correspondingly, Ni21Mo2B6 phase with a lattice parameter of a = 1.0498 nm. The τ phase probably forms coherently to the fcc crystal lattice of solid solution because of its lattice parameter is equal to three lattice parameter of nickel. According to the data of local X-ray spectral analysis, the compacted alloys are heterogeneous and are contained boron-reach and also niobium- and molybdenum-rich regions. © 2012 Elsevier B.V. All rights reserved.

Tsidaeva N.I.,North Ossetian State University | Abaeva V.V.,North Ossetian State University | Magkoev T.T.,North Ossetian State University
Acta Physica Polonica A | Year: 2012

The magnetic and magneto-optical properties of the typical representatives of three rare-earth iron garnets (RIG) groups: with heavy rare-earth elements Yb, Er, Dy, Tb; with elements from the middle of lanthanide series Gd, Sm, and with light rare-earth element Nd are presented. In contradistinction to other work on the Faraday rotation, which were done only at 1152 nm (8696 cm -1), here we present FR spectra obtained in the energy region 5500-20000 cm -1 with high optical resolution. The investigations have been done at temperatures of 5, 82, 130, 295 K using magnetic field up to 25 kOe applied parallel to the [111] crystallographic axis of the crystals. It has been shown that the contribution proportional to the magnetic field and independent of temperature to the mixing of the ground state multiplets exceeds the paramagnetic contribution in YbIG, ErIG, GdIG, SmIG. In Tb and Dy iron garnets contributions from the two mechanisms have opposite signs, and the paramagnetic mechanism gives the greatest contribution to the Faraday rotation. Nevertheless, the contribution of the diamagnetic mechanism, caused by the influence of the exchange field in the iron sublattices on rare-earth ions, is significant, and it is necessary to take it into account. Anomalously large magneto-optical activity is observed in NdYIG. This is the result of contributions of the same sign and approximately equal in magnitude from the paramagnetic and diamagnetic mechanisms.

Dzgoev S.G.,North Ossetian State University
Bulletin of Experimental Biology and Medicine | Year: 2015

Effects of desmopressin (arginine vasopressin V2 receptor agonist) were studied for elucidation of the possible role of the kidneys in the regulation of blood hyaluronidase activity. Similar to vasopressin, intraperitoneal administration of desmopressin to Wistar rats increased blood hyaluronidase activity by 30%. Against the background of water load, nether desmopressin nor vasopressin increased blood hyaluronidase activity. The possibility of renal secretion of hyaluronidase into the blood as a mechanism of antidiuretic activity of vasopressin and its role in the regulation of water metabolism are discussed. © 2015, Springer Science+Business Media New York.

Kazaryan M.L.,North Ossetian State University
Telecommunications and Radio Engineering (English translation of Elektrosvyaz and Radiotekhnika) | Year: 2011

The application of the Tikhonov regularization method in the problem of modified Wiener filtering of signals by means of discrete orthogonal transformations is investigated. Regularization parameters for different discrete orthogonal transformations (DOTs) are found. Specific features of a Wiener filter depending on the spectral components are determined for different DOTs. Errors of recovery of the filtered signal with and without regularization are evaluated. These estimates demonstrate that a signal recovered by the Tikhonov regularization method is closer to the original signal than the signal recovered without the use of the regularization method. © 2011 by Begell House, Inc.

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