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1.
Graphene with a periodic array of defects in a homogeneous magnetic field is considered. We suggest a solvable model of the system. Three types of defects are studied. The spectra of the Hamiltonians have the Hofstadter butterfly type. The comparison of the spectrum for pure graphene and one for the system having defects of each type is made. 相似文献
2.
Dr. Alexey A. Mikhaylov Dr. Alexander G. Medvedev Dr. Andrei V. Churakov Dmitry A. Grishanov Dr. Petr V. Prikhodchenko Prof. Dr. Ovadia Lev 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):2980-2986
Tellurium–peroxo complexes in aqueous solutions have never been reported. In this work, ammonium peroxotellurates (NH4)4Te2(μ‐OO)2(μ‐O)O4(OH)2 ( 1 ) and (NH4)5Te2(μ‐OO)2(μ‐O)O5(OH)?1.28 H2O?0.72 H2O2 ( 2 ) were isolated from 5 % hydrogen peroxide aqueous solutions of ammonium tellurate and characterized by single‐crystal and powder X‐ray diffraction analysis, by Raman spectroscopy and thermal analysis. The crystal structure of 1 comprises ammonium cations and a symmetric binuclear peroxotellurate anion [Te2(μ‐OO)2(μ‐O)O4(OH)2]4?. The structure of 2 consists of an unsymmetrical [Te2(μ‐OO)2(μ‐O)O5(OH)]5? anion, ammonium cations, hydrogen peroxide, and water. Peroxotellurate anions in both 1 and 2 contain a binuclear Te2(μ‐OO)2(μ‐O) fragment with one μ‐oxo‐ and two μ‐peroxo bridging groups. 125Te NMR spectroscopic analysis shows that the peroxo bridged bitellurate anions are the dominant species in solution, with 3–40 %wt H2O2 and for pH values above 9. DFT calculations of the peroxotellurate anion confirm its higher thermodynamic stability compared with those of the oxotellurate analogues. This is the first direct evidence for tellurium–peroxide coordination in any aqueous system and the first report of inorganic tellurium–peroxo complexes. General features common to all reported p‐block element peroxides could be discerned by the characterization of aqueous and crystalline peroxotellurates. 相似文献
3.
Medvedev A. G. Sharipov M. Yu. Mikhaylov A. A. Grishanov D. A. Churakov A. V. Prikhodchenko P. V. 《Russian Journal of Coordination Chemistry》2021,47(10):670-678
Russian Journal of Coordination Chemistry - Sodium and potassium tert-butyl peroxide hydrates 2Na+·2C4H9 $${\text{O}}_{2}^{ - }$$ ·7H2O (I) and 2K+· 2C4H9 $${\text{O}}_{2}^{ - }$$... 相似文献
4.
A. A. Grishanov 《Polymer Science Series D》2014,7(2):118-121
This paper presents the results of research on creating composites using the DEG-1 water-soluble epoxy resin cured by polyethylenepolyamine. It was shown that the obtained composites, in which quartz sand or Portland cement were used as the filler, have high damping properties, rigidity, and bending compressive strengths. 相似文献
5.
The behavior of the microband domain structure of films having pronounced crystallographic anisotropy is Investigated in rotating magnetic fields. In small fields, passing through the difficult axis, discontinuities are observed on the curves of mechanical moments which are associated with the reorientation of the magnetic moment by 90°. At the same time a new metastable transient domain phase appears in the form of wide bands stretched along the difficult axis.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 3#x2013;6, June, 1985. 相似文献
6.
I. N. Bardasov A. Yu. Alekseeva N. L. Malyshkina O. V. Ershov D. A. Grishanov 《Russian Journal of Organic Chemistry》2016,52(6):830-833
Three-component condensation of aliphatic aldehydes with resorcinol and malononitrile dimer (2-aminoprop-1-ene-1,1,3-tricarbonitrile) afforded the corresponding 5-alkyl-2,4-diamino-8-hydroxy-5H-chromeno[2,3-b]pyridine-3-dicarbonitriles. 相似文献
7.
A. A. Mikhaylov A. G. Medvedev D. A. Grishanov T. A. Tripol’skaya E. A. Mel’nik P. V. Prikhodchenko O. Lev 《Russian Journal of Inorganic Chemistry》2017,62(12):1624-1631
A composite based on sodium germanate and reduced graphene oxide was obtained for the first time by precipitating the initial peroxogermanate on a graphene oxide followed by heat treatment in vacuum. According to powder X-ray diffraction, sodium germanate crystallizes during the heat treatment in vacuum at 500°C. Scanning transmission electron microscopy examination showed that sodium peroxogermanate nanoparticles form a thin film on the surface of graphene oxide flakes. The electrochemical characteristics of composites obtained with different heat treatment conditions were studied as the anodes of lithium ion batteries. 相似文献
8.
Back Cover: Peroxide Coordination of Tellurium in Aqueous Solutions (Chem. Eur. J. 9/2016) 下载免费PDF全文
9.
S.A. Grishanov 《Topology and its Applications》2008,155(16):1757-1765
A new family of weight systems of finite type knot invariants of any positive degree in orientable 3-manifolds with non-trivial first homology group is constructed. The principal part of the Casson invariant of knots in such manifolds is split into the sum of infinitely many independent weight systems. Examples of knots separated by corresponding invariants and not separated by any other known finite type invariants are presented. 相似文献
10.
Bochek A. M. Zabivalova N. M. Shamolina I. I. Grishanov S. A. 《Russian Journal of Applied Chemistry》2002,75(9):1517-1521
Isolation of pectins form flax pedicels and fibers was studied. Isolated pectins and flax fibers treated by various chemical procedures were studied by IR spectroscopy. The morphology of fascicles of flax fibers was studied by electron microscopy as influenced by chemical treatment. 相似文献