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The article is devoted to the problems of definition, classification and genesis of the Epigravettian in the Central regions of the East European plain. It is concluded that Epigravettian sites could be characterized as industrially variable and multicultural. Epigravettian should be considered as a polygenetic phenomenon characterized by a cultural mosaic peculiar to specific geographical regions. In relation to the territory of the Desna and the Middle Dnieper Basin, we can assume a direct continuity between the local Gravettian and Epigravettian traditions, despite changes in technology and typology of stone and bone tools, as well as the style in the design of portable art objects.

The paper solved the problem of optimizing the piston skirt profile in the hot state according to the criteria of minimal frictional losses. The authors defined and improved the geometrical parameters of the piston design considering the optimum profile of the skirt; developed recommendations for improving the design of the piston. For six-cylinder V-shaped forced diesel engine, with a cylinder diameter of 150mm and a piston stroke of 160mm (further diesel) a piston design with improved tribological parameters was developed.

The article presents the results of a comprehensive approach to the research and development of technical solutions for the main tribosystems of six-cylinder V-shaped forced diesel engine, with a cylinder diameter of 150mm and a piston stroke of 160mm (further diesel). Technical solutions for diesel are evaluated by solving the problem of dynamics and lubrication of friction units on the basis of a single algorithm for hydrodynamic tribosystems with the reciprocation and rotation movement of the elements with a non-Newtonian fluid

The present paper discusses the spatial and stratigraphic analysis of an assemblage of archeological remains from the newly found point B (lettered in Cyrillic) of the Eastern Gravettian site Khotylevo 2. The new find was discovered by the Khotylevo Archaeological Expedition in 2005. The cultural layer of the site relates to a level of initial soil formation at the base of the Desna loess horizon. The stratigraphic position of the cultural layer at point B is typical of the entire Khotylevo 2 site and does not differ substantially from those at points А and Б. Currently, two closely related assemblages of archeological remains have been discovered at point B over an area of 45 m 2 . The first assemblage is noted for the presence of rounded shallow pits and embedded mammoth bones surrounding concentrations of bone coal; it also contains split animal bones, and flint splinters. Similar assemblages were discovered by F.M. Zavernyaev during the excavations at Khotylevo 2 in the 1970s. The second assemblage is marked by large clusters of intentionally arranged bones of woolly mammoth (Mammuthus primigenius). There is a certain pattern traceable in the bone arrangement, similar to those observed in mammoth bone structures of the Anosovka-Mesin dwellings. Microstratigraphic correlation of the two assemblages considered together with the radiocarbon dates strongly suggests them to be of different ages. The most abundant bone remains within the studied area belong to woolly mammoth. The list of mammal species identified from this site shows no significant difference from species lists known from other sites of the Russian Plain dated to the same chronological interval. The scarcity of bones belonging to other herbivorous mammals may be due to the fact that no butchering was performed at this part of the site. The abundance of mammoth bones does not directly indicate simultaneous overkill of those animals; it is quite possible, however, that individual animals were killed periodically.

The paper analyzes the numerical model of interaction between the rough surfaces of a piston-cylinder liner tribosystem in the form of a Markov chain. It is based on a model that takes into account elastic and plastic deformation and fatigue failure under load. We have provided a system of equations for the distribution of time-varying heights of protrusions. We have also analyzed the evolution of distributions for the contact interface of the piston-cylinder liner tribosystem of the diesel engine.

Complexation of the chiral P , N -bidentate ferrocene- and cymantrene-based iminoarylphosphites with [Rh(CO) 2 Cl] 2 , [Rh(COD)(THF) 2 ]BF 4 , [Pd(allyl)Cl] 2 , [Pt(allyl)Cl] 4 , [Pd(COD)Cl 2 ] and [Pt(COD)Cl 2 ] was found to give chelate complexes [Rh(CO)(η 2 -P,N)Cl], [Rh(COD)(η 2 -P,N)]BF 4 , [M(allyl)(η 2 -P,N)]BF 4 (M = Pd, Pt) and cis -[M(η 2 -P,N)Cl 2 ] (M = Pd, Pt), correspondingly. With the new P , N -ligands, up to 97% ee was achieved in the asymmetric Pd-catalysed alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate. In the enantioselective amination of 1,3-diphenyl-2-propenyl acetate with sodium diformylamide, up to 96% enantioselectivity was achieved.

The coordination of new chiral P,N-hybrid ligands possessing a phosphite-type phosphorus donor centre and azomethine nitrogen to [Rh(CO)2Cl]2 and PdCl2(cod) was examined.