Experimental measurements and molecular statistics methods were used to calculate ther modynamic characteristics of adsorption (TCA) of alkyladamantanes of different structure on the surface of hydrogen treated graphitized thermal carbon black (GTCB) Carbopack C HT. High selectivity of separation of isomeric alkyladamantanes on GTCB is due to specific features of their geometry and electronic structure. The influence of the spatial structure of adsorbates on the TCA was established. Special attention was given to analysis of the heat capacities of adsorption. The best agreement between the experimental TCA and those calculated by the molecular statistics methods is achieved when the "cage effect" in the adamantane ring is taken into account. The corresponding corrections are introduced into the parameters of the atom atomic potential function of pair intermolecular interaction of the Me groups with the carbon atoms of the basal face of graphite, which are localized in the nodal positions of the lattice. The critical parameters for a large group of alkyladamantanes were calculated in terms of the addi tive group Lydersen method. A set of various topological indices used further for constructing structure-retention correlations on GTCB was obtained.At present the single natural source of adamantane and its alkyl derivatives is petroleum. 1-8 Alkyladamantanes of certain molecular weight are usually presented by mixtures of many isomers differed by both the structure of the alkyl group and the number and position of substituents in the adamantane skeleton. Isomeric alkyladamantanes often differ insignificantly from each other by physicochemical properties, which impedes their analysis and separation. There are a number of methods of isolating and concen trating alkyladamantanes such as thermodiffusion separa tion, formation of adducts with thiocarbamide, azeotropic distillation with steam or with tri(perfluorobutyl)amine. 2-4 A leading role belongs to preparative GLC followed by identification of isomers by high performance capil lary GLC on stationary phases (SP). 2,9-14 However, in spite of achieved success in studying the chromatographic behavior of this group of compounds under the GLC con ditions, a series of questions related to efficient separation and identification of some isomers with similar structure even in relatively narrow fractions remains unanswered so far. 2-5,10,12-14 The influence of specific features of the molecular structure of the adamantane framework on the chromato graphic behavior of adamantane derivatives under the con ditions of gas chromatography was studied by many au thors. It was found 15-19 by gas adsorption chromatogra phy (GAC) of adamantyl containing compounds on graphitized thermal carbon black (GTCB) that a possible reason for the different adsorption behavior of 1 and 2 functional adamantane derivatives is the "cage effect" in the adamantane system resulting in adsorption nonequiv alence of the substituents in the nodal and bridging posi tions of the adamantane framework. Analo...

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The purpose of this article is to analyze and identify the key problems and reserves of growth of innovative activity of Russian industrial enterprises from the standpoint of the principles of development of the new economy. The works of domestic and foreign authors were studied to achieve this purpose. The study included methods of system analysis, methods of expert survey, method of statistical data analysis, which together allowed identifying the essence of the problem under study. The results of research were aimed at identifying the role of digital innovation, i.e. the introduction and use of new information and communication technologies to improve and manage business processes, increase the competitiveness of the domestic economy.

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