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Balyts'kyi O..,Ukrainian Academy of Sciences | Kolesnikov V.O.,Shevchenko Lugansk National University | Eliasz Y.,West Pomeranian University of Technology | Havrylyuk M.R.,Ukrainian Academy of Sciences
Materials Science

It is shown that, in the course of rolling friction, the intensity of wear of hydrogenated specimens of high-nitrogen manganese steels is five times higher than for nonhydrogenated specimens. As the wear intensity increases, the color of the friction surface of the roller and the sizes of the wear products change. The outward appearance of nonhydrogenated and hydrogenated wear products is noticeably different (white and dark colors, respectively). The microhardness of the hydrogenated layer is equal to 7.6–8.2 GPa, whereas the microhardness of the layer of destroyed domains is 4.2–4.9 GPa. In the destroyed domains with signs of thermal seizure, we observe the elevated contents of carbide-forming elements (in particular, of molybdenum), which confirm the intensification of fracture in the investigated high-nitrogen steels under the conditions of rolling friction in carbide-enriched domains. © 2015 Springer Science+Business Media New York Source

Dyachenko I.V.,Shevchenko Lugansk National University | Vovk M.V.,Ukrainian Academy of Sciences
Russian Journal of General Chemistry

4-Carbamoyl(thiocarbamoyl)-3-thioxo-2,3,5,6,7,8-hexahydroisoquinolines were synthesized by the SNVin reaction of 2-acetyl-1-(N-morpholinyl) acetylcyclohexene with malonothio(dithio)amides. The cyclo-condensation direction was confirmed with the X-ray diffraction analysis of 1-methyl-3-methylthio-5,6,7,8-tetrahydroisoquinoline-4-carboxamide. © Pleiades Publishing, Ltd., 2012. Source

Abstract Recyclization of 2,6-diamino-4-hetaryl-4H-thiopyran-3,5-dicarbonitriles with α-bromoketones afforded 2-[4-aryl(hetaryl, cyclopropyl)thiazol-2-yl]-3-hetarylacrylonitriles. © 2015 Pleiades Publishing, Ltd. Source

Zvonok E.A.,Shevchenko Lugansk National University | Skutschas P.P.,Saint Petersburg State University
Paleontological Journal

A dentary fragment and osteoderm of the crocodile Tomistominae indet. from the Middle Eocene (Early Lutetian) Ikovo locality (Lugansk Region, Ukraine) is described. © 2011 Pleiades Publishing, Ltd. Source

Saraevaa T.A.,Shevchenko Lugansk National University | Khoroshilova G.E.,Shevchenko Lugansk National University | Zubatyuk R.I.,Ukrainian Academy of Sciences | Shishkin O.V.,Ukrainian Academy of Sciences | Shishkin O.V.,University of Kharkiv
Russian Journal of General Chemistry

Reactions of N-alkyl-2-chloropyridinium salts with benzimidazolylacetonitriles result in (E)-2-(1H-benzo[d ]imidazol-2-yl)-2-[1- alkylpyridin-2(1H)-ylidene]acetonitriles. The alkylation of the latter with ω-bromoacetophenones in boiling acetone may gives rise to the N-alkylated salts, which are stabilized in two configurations, Z and E. The heating of the salts in acetonitrile causes their transformation into 2-({1H-benzo[d ]-imidazol-2(3H)-ylidene}(cyano)methyl)-1-methylpyridinium bromide due to the dearoylmethylation. The structure of the latter was proved by the XRD analysis. © 2012 Pleiades Publishing, Ltd. Source

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