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Composites comprising MoVTeNbO mixed oxide and zirconia-pillared montmorillonite clays (PilCs) were prepared. XRD and TEM with EDX studies confirmed the preservation of M1 MoVTeNbO phase in these composites responsible for high activity and selectivity in ethane oxidative dehydrogenation into ethylene. For composites with PilC content of 10 wt%, the best ethylene yield exceeding that of bulk MoVTeNbO oxide was demonstrated for clays with zirconia pillars doped with Ce and Al possessing the highest specific surface area. This is explained by optimized chemical interaction of these clays with MoVTeNbO mixed oxide improving its bulk oxygen mobility and reactivity by structure disordering while blocking surface sites responsible for combustion due to the stabilization of the reactive terminal oxygen species.

For the first time, the distribution of methane in the brine and bottom sediments of the Ulan-Blag stream (tributary of Lake Baskunchak), fed by underground degassing springs, as well as directly in Baskunchak Lake at a distance from underground sources. The composition of the main ions in brine, acid-base and redox conditions in bottom sediments have been established. The brine mineralization in Baskunchak Lake is 312 g/dm3, which is 2.1 times higher than the mineralization of the Ulan-Blag stream. The chemical composition of the brine of both stations is classified as chloride type, sodium cationic composition. The concentration of methane in the brine of the studied underground degassing sources in the ravine stream of the Ulan-Blag reaches high values (up to 215 µl/dm3), exceeding by 1–2 orders of magnitude its concentration in the brine of Lake Baskunchak. The low concentrations of methane in the brine of the lake are probably due to its insignificant flow from the bottom sediments into the water due to the presence of a salt crust that prevents gas emission, as well as due to its small concentrations in the upper layers of sediments.

The article provides a brief description of the geological and tectonic structure and technogenic transformations in the drainage basin of two lakes of the Krasnodar Krai (Malyy Liman and Abrau). They belong to a single natural-technogenic system. On the example of these mountain lakes, the grain-size distribution, elemental (mercury) and isotopic (cesium-137) composition of bottom sediments was studied. The use of a set of methods and technologies, including those developed by the authors, made it possible to determine the parameters of the anthropogenic impact layer in bottom sediments and the chronology of its formation. It is closely related to natural and man-made events in the drainage basin.

Seventy-eight cases of enterovirus infection, including 25 neuroinfections, occurred in Rostov-on-Don, Russia, during May-June 2013. The outbreak was caused by an enterovirus A type 71 (EV-A71) subgenotype C4 lineage that spread to neighboring countries from China ≈3 years earlier. Enterovirus associated neuroinfection may emerge in areas with a preceding background circulation of EV-A71 with apparently asymptomatic infection.