Irkutsk State Pedagogical University

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Irkutsk, Russia

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Semenov A.L.,Irkutsk State University | Gavrilyuk A.A.,Irkutsk State University | Gavrilyuk A.V.,Irkutsk State Pedagogical University | Semirov A.V.,Irkutsk State Pedagogical University | And 4 more authors.
Inorganic Materials | Year: 2010

We have studied the effect of laser processing conditions on the dynamic magnetic properties of amorphous Fe 64Co 21B 15 ribbons. The results indicate that the laser beam scan speed and direction on the sample surface relative to the axis of rolling play a key role in determining the variation of the relative dynamic magnetic permeability with magnetic field and its sensitivity to elastic tensile stress. © Pleiades Publishing, Ltd., 2010.


Korlyukov A.A.,RAS Nesmeyanov Institute of Organoelement Compounds | Antipin M.Y.,RAS Nesmeyanov Institute of Organoelement Compounds | Buzin M.I.,RAS Nesmeyanov Institute of Organoelement Compounds | Zel'bst E.A.,Irkutsk State Pedagogical University | And 3 more authors.
Journal of Structural Chemistry | Year: 2010

Using X-ray diffraction the presence of two phases of 1-fluorosilatrane (FSa) is stated and the specific features of their spatial structure are studied. Phase transition occurs at 156-158 K and is characterized by low energy. In the low-temperature phase, four crystallographically independent molecules are ordered, while in the high-temperature phase one of two independent molecules has disordered carbon β-atoms. A quantum chemical analysis of crystal packing in the low-temperature FSa phase is performed. The estimated value of the coordination N→Si bond strength in the crystal is 29. 2 kcal/mol. The charge distribution indicates the localization of valence electron density around the O3SiF fragment. © 2009 Springer Science+Business Media, Inc.


Voronkov M.G.,Favorsky Irkutsk Institute of Chemistry | Korlyukov A.A.,RAS Nesmeyanov Institute of Organoelement Compounds | Zel'bst E.A.,Irkutsk State Pedagogical University | Grebneva E.A.,Favorsky Irkutsk Institute of Chemistry | And 2 more authors.
Journal of Structural Chemistry | Year: 2010

X-ray diffraction is used to determine the crystal and molecular structure of spirocyclic (C=O→Si←O′=C′) bis(2-methyl-4-pyrone-3-oxy)difluoro(λ6)siliconium containing a hypervalent silicon atom and the previously unknown F2SiO4 coordination center. The coordination polyhedron of the silicon atom is a slightly distorted octahedron. © 2009 Springer Science+Business Media, Inc.


Semirov A.V.,Irkutsk State Pedagogical University | Bukreev D.A.,Irkutsk State Pedagogical University | Moiseev A.A.,Irkutsk State Pedagogical University | Volchkov S.O.,Ural Federal University | And 3 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2012

The influence of a magnetic field or the mechanical stresses on the impedance of the Fe 73.5Si 16.5B 6Nb 3Cu 1 and Fe 73.5Si 13.5B 9Nb3Cu 1 ribbons was investigated in the (297/433) K temperature range. It is shown that impedance changes, which are observed under the application of mechanical stresses and temperature, are conditioned by the structural features and magnetic properties of the alloys. The temperature increase leads to a decrease of the saturation magnetostriction constant, an increase of the anisotropy axis dispersion and a decrease of the anisotropy effective value. It was determined that the maximum sensitivity of impedance to the mechanical stresses reaches the value of about 2%/MPa for the Fe 73.5Si 16.5B 6Nb 3Cu 1 and Fe 73.5Si 13.5B 9Nb 3Cu 1 samples. Copyright © 2012 American Scientific Publishers All rights reserved.


Voronkov M.G.,RAS Institute of Chemistry | Korlyukov A.A.,RAS Nesmeyanov Institute of Organoelement Compounds | Zelbst E.A.,Irkutsk State Pedagogical University | Knyazev S.P.,RAS Nesmeyanov Institute of Organoelement Compounds | And 3 more authors.
Journal of Structural Chemistry | Year: 2010

The crystal structures of anhydrous 1-germatranol and its complex with HCCl 3 are centrosymmetrical dimers because of their intermolecular hydrogen bonds. In the germatranol crystal, the axial and equatorial oxygen atoms of its two molecules are hydrogen bonded into an eight-membered coordination cycle. In the complex with HCCl 3, the two molecules of germatranol are likewise linked in dimers, and both axial oxygen atoms are H bonded with HCCl 3. In the investigated structures, the axial Ge-O bond is shorter than the equatorial ones. Depending on the number and strength of the hydrogen bonds, the interatomic Ge-O and Ge ← N distances change markedly. The quantitative estimates of the H bond energy are obtained from quantum chemical calculations of the model systems containing 1-germatranol and HCCl 3 molecules. © 2010 Pleiades Publishing, Ltd.


Semirov A.V.,Irkutsk State Pedagogical University | Bukreev D.A.,Irkutsk State Pedagogical University | Moiseev A.A.,Irkutsk State Pedagogical University | Lukshina V.A.,RAS Institute of Metal Physics | And 3 more authors.
Technical Physics | Year: 2011

The temperature dependences of the magnetic properties and the magnetoimpedance effect of soft magnetic nanocrystalline Fe 73.5Si 16.5B 6Nb 3Cu 1 alloy ribbons are studied in the temperature range 24-160°C. A high temperature sensitivity of the impedance and the magnetoimpedance effect of the ribbons are detected in the ac frequency range 0.1-50 MHz. At an ac frequency of 50 MHz, the change in the impedance reaches 0.2 Ω/°C (0.5%/°C) in the temperature range 85-160°C. When the temperature increases, a monotonically decreasing character of the dependence of the magnetoimpedance effect on the applied magnetic field changes into a dependence having an increasing initial segment. The effect of temperature on the magnetoimpedance properties of the soft magnetic nanocrystalline ribbons is shown to result from temperature-induced changes in their electrical conductivity, magnetization, and effective magnetic anisotropy. © 2011 Pleiades Publishing, Ltd.


Stanevich A.M.,Russian Academy of Sciences | Mazukabzov A.M.,Russian Academy of Sciences | Kornilova T.A.,Russian Academy of Sciences | Maksimova E.N.,Irkutsk State Pedagogical University
Lithology and Mineral Resources | Year: 2012

First finds of microfossils from the silicified microphytolitic carbonates of the Uluntui Formation in the southwestern Baikal region are described. They are represented by remains of the cyanobacterial community that formed microphytolites. These microfossils are accompanied by acritarchs probably belonging to green algae. The silicified microfossils are sufficiently well preserved despite complete and repeated recrystallization of host primary carbonate rocks. Main phases of secondary mineralization are related to hydrothermal-metasomatic processes, which were likely provoked by collisional events on the southern flank of the Siberian Craton in the Silurian. © 2012 Pleiades Publishing, Ltd.


Kulikova N.N.,Russian Academy of Sciences | Suturin A.N.,Russian Academy of Sciences | Saibatalova E.V.,Russian Academy of Sciences | Boiko S.M.,Russian Academy of Sciences | And 3 more authors.
Geochemistry International | Year: 2011

Based on materials collected in 2003-2007, data on aquatic lichens of the genus Verrucaria from the rocky littoral zone of Lake Baikal are discussed. The maximum density of their occurrence was observed at a depth of 1.5 m; 95-100% of rock fragments recovered from depths of 1. 5-2.2 m are encrusted by 24-43% with the thalli of Verrucaria spp. It was found that the lichens contribute actively to the physical and physicochemical weathering of their rock substrate and prefer to reside on the rocks of granitic composition. The chemical composition of aquatic verrucaria is dominated by the same elements that are most abundant in the rocks (Ca > K > Fe > Al > Mg > P > S > Na > Mn > Sr > Ba), and, in most cases, the characteristic element ratios of the rock compositions are preserved in the composition of the thalli of Verrucaria spp. Compared with the elemental composition of the near-bottom water layer, the lichens most extensively concentrate the elements that slowly migrate in water: Gd > Sm > Pr > Nd > Al > La > Dy > Tb > Y > Lu > Ce > Yb > Be > Tm > Co > Nb > Mn > Zn. Compared with the composition of rocks, the mineral composition of the thalli of Verrucaria spp. is enriched by a factor of 100-10 in Hg > As > P > Zn > Li > S > U > Mo > Se > Cd > Ca > Tl > Sr > Pb > Be. © 2011 Pleiades Publishing, Ltd.


PubMed | Irkutsk State Pedagogical University
Type: Journal Article | Journal: Journal of nanoscience and nanotechnology | Year: 2012

The influence of a magnetic field or the mechanical stresses on the impedance of the Fe73.5Si16.5B6Nb3Cu1 and Fe73.5Si13.5B9Nb3Cu1 ribbons was investigated in the (297 divided by 433) K temperature range. It is shown that impedance changes, which are observed under the application of mechanical stresses and temperature, are conditioned by the structural features and magnetic properties of the alloys. The temperature increase leads to a decrease of the saturation magnetostriction constant, an increase of the anisotropy axis dispersion and a decrease of the anisotropy effective value. It was determined that the maximum sensitivity of impedance to the mechanical stresses reaches the value of about 2%/MPa for the Fe73.5Si16.5B6Nb3Cu1 and Fe73.5Si13.5B9Nb3Cu1 samples.

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