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The work noted the relevance of the development of the military-industrial complex of Russia. An analysis of sales volumes of a number of the largest enterprises of the military-industrial complex of the Russian Federation was carried out, as a result of which two leading organizations were identified. The value of the sales indicator for one analyzed enterprise was evaluated, indicating the reasons for the high results in three enterprises. Based on the analysis of data on the number, conclusions were made about the priority of large enterprises in the structure of the military-industrial complex of the Russian Federation and about the rather serious attention paid by the state to the development of the military economy in modern conditions. When considering the territorial location of the analyzed enterprises, the employment of employees of large organizations of the MIC industries in various regions of Russia is clearly shown, which serves as one of the main factors in the development of the regional economy throughout the country. It was noted the place of the largest enterprises of the military-industrial complex in the ranking of the 100 largest military-industrial companies in the world, based on income from sales of military products by world manufacturers in 2020. The build-up of the country's military power directly depends on the potential of military-industrial complex enterprises and the directions of their development. In the ranking of the analytical company GlobalFirepower for 2020, Russia was ahead of China, but lost to the United States. There are different opinions about the objectivity of this and similar ratings. However, it is impossible not to pay attention to the values of those factors in the GlobalFirepower rating, which indicate insufficient attention to them from the military-industrial complex of the Russian Federation at the present time.

We have studied the catalytic activity of LiZr2(PO4)3-based NASICON-type phosphates for conversion of C2 and C3 aliphatic alcohols with the aim of selectively preparing C2–C4 olefins. Selectivity has been controlled via partial heterovalent substitutions of In3+ or Nb5+ for Zr4+ or Mo for phosphorus. We have investigated the structure and morphology of the synthesized catalysts. The nature of the dopants has been shown to play a key role in determining the selectivity of the catalysts studied. Partial In3+ substitution for Zr4+ improves the dehydrogenating properties of the materials, whereas partial substitutions of Nb5+ for Zr4+ and Mo6+ for P5+ improve their dehydrating properties. We have demonstrated the possibility of highly selective preparation of ethylene and butylenes from ethanol and of propylene from propanol-1 and propanol-2.

The article presents the results for obtaining the conditioned target product from metallurgical waste, such as vanadium-containing converter slag, steelmaking slag and magnesium-containing fused periclase, by increasing their particle surface reactivity through mechanical activation at the grinding stage. The paper presents the characteristics of the feed and grinding products and the process flows for the processing of respective technogenic raw materials. The dispersion and reactivity of the finely dispersed product, established by the change in the material wetting heat, and the role of mechanical activation for the subsequent processing and improvement of the resulting product grade are evaluated. Mechanical activation of magnesium oxide powder at the last processing stage for low-grade fused periclase promotes an increase in the energy of surface-active centers of the ground material and an improvement in its electrical insulating properties (as compared with ball grinding). Mechanochemical activation of vanadium slag promotes the formation of homogeneous, well-permeable granules, intensification of redox processes during leaching and obtaining the target product (V2O5 paste) with the mass fraction of vanadium pentoxide of 84–86 %. An increase in the reactivity of the dump steelmaking slag during mechanochemical activation allows obtaining high-activity composite cements with the slag content of up to 20 wt.%.

A study of methanol steam reforming (MSR) in the presence of a Ni0.2–Cu0.8/Ce0.3Zr0.7O2-δ catalyst in conventional and membrane reactors has revealed that the hydrogen yield in a reactor with a Pd–Cu membrane is higher than that in a conventional flow reactor. It has been shown that the Pd–Cu alloy membrane exhibits high hydrogen permeability. Methanol steam reforming in the membrane reactor provides the production of high-purity hydrogen, because a stream of pure hydrogen free from any impurities is effluent from the permeate zone. Measurements of the hydrogen permeability of the Pd–Cu alloy foil membrane in the membrane reactor before and after catalysis have been conducted.

The possibility of paraffins and C4 olefins mixture separation on membranes made of polyethylene with radiation-grafted sulfonated polystyrene is shown. The selective separation is achieved due to the butenes and isobutene facilitated transfer in the form of a π-complex with a proton. Moreover, despite the significantly larger cross-sectional size, obstructing the transfer, isobutene molecules are also transferred much faster than butane, and the separation coefficient reaches 3.8. An unusual fact was discovered of separation selectivity and permeability increase with the separated gases flow humidity rise.

—The diagenesis of organic matter (OM) is studied in bottom sediments taken in February, 2018 from therapeutic mud deposits of the Uglovoi Bay and Voevoda and Ekspeditsiya bights (Peter the Great Bay, Sea of Japan). The carbonate system of bottom sediments and pore water were analyzed for the contents of nutrients, dissolved organic carbon, humic substance, and concentrations of sulfates and chlorides. The concentrations of organic carbon, chlorophyll-a, humic and fulvic acids, and mobile sulfide species are measured in a solid phase of sediment. Underwater photographing shows that sampling localities are covered by Zostera marina meadows in the Voevoda and Ekspeditsiya bights and by diatom mats in Uglovoi Bay. The proportions between dissolved inorganic carbon and alkalinity, as well as data on sulfate–chlorine ratios and mobile sulfide species indicate that the OM degradation in bottom sediments is mainly controlled by sulfate reduction. The Uglovoi Bay and Voevoda and Ekspeditsii bights are characterized by different values of bioturbation coefficients: 3.0, 107.6, and 14.5 cm2/day, respectively. The estimated fluxes of organic carbon from water into sediment and of dissolved inorganic carbon from sediment into water significantly differ. The disbalance between organic and inorganic carbons can be caused by the following reasons: (a) ignored CO2 flux released by marine organisms from bottom sediments through their siphonal system; (b) partial OM consumption in food with its subsequent deposition in it.

Purpose. The work is aimed at estimating the organic carbon abundance in the bottom sediments of the littoral zone in connection with the state of macrozoobenthos in the Sevastopol region coastal waters with different levels of the anthropogenic pressure (by the example of the Laspi Bay). Methods and Results. The samples were taken in the dynamically active coastal-shelf zone (up to the depths ~ 20 m) of the Laspi Bay in September, 2017. Two samples were taken during the 103rd cruise of R/V "Professor Vodyanitsky" (September, 2018). The geochemical composition of bottom sediments was investigated. The bottom sediments of natural humidity were analyzed in accordance with the requirements of the regulatory documents. In the sediments containing the aleurite fraction in the central part of the Laspi Bay (station 4), the organic carbon content (Сorg) increased its natural course up to 0.46 %, but did not exceed its maximum values characteristic of the similar lithological sediments in the shallow-water part of the Crimea Southern Coast (1.14 %). In the deep part of the bay occupied with the aleurite-pelitic silt, the Сorg content exceeded 2 %. Absence of the Сorg accumulation within the depths under study is conditioned primarily by the grain-size composition of the bottom sediments, the hydrodynamic factor and the morphometric features of this coastal site. Presence of a small portion of the aleurite-pelitic fraction in the bottom sediments also does not promote the organic carbon accumulation. Thus, spatial distribution of the carbon organic and inorganic forms is conditioned by the features of the matters’ lateral migration, which, in its turn, is governed by dependence of the bottom sediments’ chemical and dispersion structure upon the environmental morphodynamic conditions. Conclusions. The littoral sediments were found to be characterized by a low organic content (Сorg = 0.16 %) not exceeding the geochemical background values of the surface bottom sediments in the Black Sea shelf zones. At present, the organic matter accumulation is determined by the features of the environmental morphodynamic conditions (transition of fine particles to the deep zones) and by the dispersed composition of the bottom sediments.

We have studied the catalytic activity of Cu–Ni bimetallic catalysts on yttrium-, tin-, zinc-, and niobium-doped zirconia and ceria supports for methanol steam reforming (MSR), a process for hydrogen production, and examined the effect of the nature of the dopants and annealing temperature on the structure and particle size of the oxide supports and the catalytic activity of the metal oxide composites. In all cases, the addition of heterovalent ions improved the catalytic activity of the materials for the MSR process in comparison with undoped zirconia. The highest hydrogen yield was reached in the case of catalysts doped with niobium and yttrium oxides.

Lack of a systematic and environmentally efficient approach to exploitation of bays of Sevastopol (Kruglaya and Kazachya bays) resulted in their severe pollution. The combination of natural and anthropogenic factors led to the deterioration of the benthic communities living conditions. The purpose of this work was a complex research of Kruglaya and Kazachaya bays’ ecosystems to study features of redox conditions formation in the bottom sediments and the bottom waters and their influence on the characteristics of macrozoobenthos. Samples of bottom sediments were taken by diver in plexiglass tubes, hermetically closed above and below, it allowed to save a fine structure of bottom sediments and the bottom layer of water. To study benthic communities, samples were taken in the same place using a manual sampler. To obtain the chemical composition of pore waters with high vertical resolution, the voltammetry analysis was used. Calculation of the oxygen flux at the boundary and in the upper part of the bottom sediments was carried out according to the vertical profile of oxygen concentration in pore waters and geochemical analyzes using the equation for the first Fick law taking into account the concentration gradient and molecular diffusion of oxygen in pore waters. Standard hydrobiological methods were used for the analysis of benthic material. When calculating the values of the Shannon diversity index (H'), the base 2 logarithm was used. The data analysis showed that a high level of anthropogenic impact and restricted water dynamics led to siltation of the bottom sediments of the investigated water areas, which made it difficult for oxygen penetration, and the accumulation of organic carbon contributed to its active consumption. Stratification of the water column due to limited water exchange, high temperature of the bottom waters, accompanied by a decrease in oxygen solubility, and finely dispersed nature of bottom sediments contributed to the fact that the rate of oxygen intake was lower than the rate of oxygen consumption for the oxidation of organic matter, which was accompanied by the development of oxygen deficiency zones and the appearance of reduced compounds, in particular hydrogen sulfide. It was noted that suboxic conditions prevailed in the upper layer of bottom sediments, and anaerobic conditions prevailed below. This had led to the fact that the main forms of macrozoobenthos were species tolerant to oxygen deficiency and organic pollution. Thus, in some parts of the Kazachaya Bay were marked only polychaetes. At the same time, it was noted that in the area of exit from Kruglyaya Bay, intense water dynamics and morphological features of the bottom sediments contribute to saturation of the upper layer of sediments with oxygen. Based on the oxygen concentration data in the surface (0 - 5 mm) sediment layer (pore water), and the geochemical composition of bottom sediments, the oxygen flux at station 4 was calculated. Its value was 0.73 M·m-2·year-1. Taking into account the concentration of oxygen in the bottom layer of water (259 μM), the time for complete exhaustion of oxygen or its renewal taking into account only biogeochemical processes was about 5 months. Thus, it can be assumed that the ecosystems of the Kruglaya and Kazachaya bays are in the stage of degradation. Its further exploitation without a developed systematic approach and rational use will lead to a critical deterioration of its ecosystem - the emergence and spread of environmental risk zones. This will reduce the recreational and socio-economic attractiveness of these areas.

Based on the data of field research performed in 2015, the authors studied characteristics of bottom sediments in the area of a deepwater sewage collector of “Yuzhnye” Integrated Sewage Treatment Plant and transformation of bottom sediments resulted from a longterm anthropogenic impact. The data were obtained by standard methods of geochemical analysis. It is established that the bottom sediments in the wastewater discharge area of “Yuzhnye” Integrated Sewage Treatment Plant are represented by rudaceous and coarsegrained fractions. These are mineral particles formed both as a result of coastal abrasion and in the process of accumulation and diagenesis (shell rock, detrital sand) of bottom sediments. In terms of their size distribution and chemical composition they differed significantly from the sediments formed under natural conditions. These were mostly unconsolidated water-saturated sediments with low carbonate content, high organic carbon and moisture content and signs (impurities, consistency, odour) characteristic of municipal sewage sludge. It is noted that the accumulation level of anthropogenic organic carbon is comparable to that of organic matter in the bottom sediments of Sevastopol region bays characterized by limited water exchange and subject to long-term anthropogenic pollution. Exceeding the previously established critical organic carbon levels in the soft soils of the Black Sea (Corg ≥ 2.5 %) results in destructive changes in ecosystems: it has a negative impact on benthos sharply changing its structural characteristics (abundance, biomass, total species richness) with restructuring of its dominant species structure.

Ethanol steam reforming (ESR) in the presence of bimetallic nanocatalysts containing Pd–Ru, Pd–Ni, Pt–Ru, and Pt–Ni alloys deposited on detonation nanodiamonds (DNDs) in conventional and membrane reactors has been studied. The effect of some ESR parameters, such as catalyst composition, water/ethanol molar ratio, and temperature, on the hydrogen yield has been studied. The highest hydrogen yield is achieved in a conventional reactor using a Pt–Ru/DND catalyst. In the case of the ESR process running in a membrane reactor and simultaneous removal of hydrogen through membranes made of Pd–Ru or Pd–Ru–In alloys, the hydrogen yield is higher than that obtained in ESR in a conventional reactor. The hydrogen recovery rate from the retentate zone is up to 46%, whereas a high-purity hydrogen stream is withdrawn from the permeate zone.

Graphite is a component of graphite-containing dust – one of wastes, formed at metallurgical plants. From the other side, it is a scare resource for the Russian industry. Involvement of graphite-containing wastes into processing can contribute to solving actual problems of resource, economic and ecological significance. Study of the graphite wastes utilization possibility showed an absence of constant practice of their processing at domestic metallurgical plants. The work of graphite department of Magnitogorsk steel-works (MMK) can be one of not numerous examples of the graphite dust processing at the same plant. At the department the processing of graphite-containing dust of accomplished, the dust being collected from 90 kg/h productivity gas cleaning systems of BOF shop. As a result of processing graphite concentrate obtained after flotation and iron powder – after magnetic separation. At the Department “Minerals enrichment” of the Magnitogorsk State Technical University after G.I. Nosov, the theory of graphite flotation is being elaborated under the direction of Professor V.B. Chizhevsky for many years. Besides study of graphite ores washability, which are difficult to be enriched is also carried out. Based on the gained extensive experience on perfection of reagent flotation modes for the graphite ores, it was recommended to use first VKP reagent at the MMK graphite department, and next – RAS foam formation agent, which is a refined sodium alkylartile-sulfonate. At the industrial tests, the RAS foam formation agent consumption was two times as lower comparing with industrial reagent mode, resulting in obtaining higher technological flotation indices. The experience of metallurgical plant graphite-containing dust processing can be used at both the MMK graphite department re-operation and at other plants of the industry for obtaining marketable products of high quality, that can meet requirements not only metallurgical plants, but also used for production of state-of-the-art carbon materials.

From 14 to 28 December 2017, in the central part of the Black Sea, within the exclusive economic zone of the Russian Federation, a joint interdepartmental comprehensive oceanological expedition was carried out on board the R/V «Professor Vodyanitsky». The main goal of the expedition was to study the characteristics of the hydrological, hydrochemical, hydro-optical and hydrobiological structure of the Black Sea waters during the winter, as well as to collect material for studying the sedimentation system of the sea, which allows assessing the particle fluxes in the water column, the rate of its sedimentation to the bottom and biogeochemical processes occurring in water and bottom sediments.

We have carried out a comparative study of the catalytic activity of nanostructured M–Ru (M = Pt, Pd, Rh) bimetallic catalysts supported on detonation nanodiamond (DND) for methanol steam reforming (MSR) and ethanol steam reforming (ESR) processes in a conventional and a membrane reactor. The catalysts have been characterized by X-ray diffraction, transmission electron microscopy, and BET measurements. In the ESR process, the highest hydrogen yield is ensured by the Pt–Ru/DND catalyst, whereas the Ru–Rh/DND catalyst exhibits the highest activity for the MSR reaction. Our results demonstrate that, if the processes in question are run in a membrane reactor with a Pd–Ru membrane, there is a stable hydrogen flow, free of CO and other impurities, in the permeate zone even at temperatures on the order of 400°C.

Results of hydrogen production study in methanol steam reforming (MSR) process with the use of Ru0.5–Rh0.5 catalysts supported on different carbon materials: synthetic graphite-like material Sibunit, carbon black Ketjenblack EC600DJ, detonation nanodiamonds (DND) and ZrO2-based material with fluorite structure, doped with ceria, have been described. The samples have been tested in conventional flow reactor and membrane (MR) reactor, containing Pd-based membranes with different composition, thickness and surface architecture. It has been shown that the catalytic activity of the composites depends on the support nature. The Ru Rh/DND catalyst exhibits the highest activity, whereas Ru Rh/Ce0.1Zr0.9O2–δ is the most selective. The use of Pd Ag (23%) foil with the surface modified by palladium black showed great advantages comparing to the smooth dense membrane. The use of the MR with the Pd Ag membrane improves the MSR reaction and provides almost 50% increase in the hydrogen yield. The hydrogen produced with the use of the MR is ultra pure.

An analysis was made of the use of magnesium-containing materials of natural and technogenic origin in complex systems for the purification of wastewater from mining enterprises from heavy metals. The transfer mechanisms of dissolved heavy metals into the precipitate and onto the surface of the sorbent have been theoretically studied. Magnesium-containing minerals in water partially undergo hydration, forming an association of complex molecules. The main purification mechanism is the formation of sparingly soluble metal hydroxides. The mechanisms of adsorption, co-precipitation, co-crystallization of impurities with products of hydration and hydrolysis of magnesium-containing minerals also work. Exploratory studies of the intensification of the wastewater treatment process using magnesium-containing materials have been carried out, which have shown that the residual concentration of almost all metals, with the exception of nickel and chromium, when using brucite at the same pH level is lower. The highest water purification efficiency is observed for zinc and lead ions. The addition of dolomite to brucite in an amount of less than 10% makes it possible to reduce the residual concentration of cadmium in water at 20-60 minutes of contact and other equal experimental conditions.

The results of investigation of the bottom sediments sampled in the Balaklava Bay in February and June, 2015 are represented. The grain-size distribution, and the organic carbon (Corg) and calcium carbonate (CaCO3) content have been studied. Noticeable change in the fractions’ content that took place in course of the last 10 years is revealed. To a greater extent it is referred to the sand or gravel material, its quantitative characteristics and the features of its spatial distribution. As for the silt material in the Balaklava Bay sediments, its content, according to all the samples, grew, on the whole, from 58 to 66 %. The changes in the organic carbon abundance that took place in the bottom sediments in 2005–2015 were comparatively analyzed both for the Balaklava Bay and other water areas of the Heraklion Peninsula. A general tendency of the organic matter abundance to decrease in the bottom sediments of the bay was noted; it is treated as a result of some alteration in the anthropogenic pressure. The organic carbon mean concentration in the Balaklava Bay bottom sediments is two to three times lower than that in the other bays of the region which were subjected to permanent anthropogenic pressure. However, pollution of the Balaklava Bay with the untreated municipal, storm and industrial sewages leads to formation of the local bottom zones where the sediments are saturated with organic matter (Corg> 2.5 %). Such phenomena can exert a negative impact on the state of the marine environment ecology including, in particular, structural deviations in the macrozoobenthos community. Further decrease of the organic matter abundance is possible only in case the pollution basic sources are either completely removed or, at least, their influence is reduced. Such a condition is indispensable due to its extreme importance for implementing the state plan to turn the Balaklava Bay into a recreational area and a yacht marina.

Catalysts used for the steam reforming and electrochemical oxidation of methanol in fuel cells are briefly reviewed. The mechanisms of these processes are discussed. Most of the methanol steam reforming catalysts contain noble metals, copper, or their alloys supported on inorganic materials. The main laws governing the steam reforming process are extended to a wider range of alcohols. The electrochemical oxidation of methanol is catalyzed by noble metals and alloys based on them. The catalyst selectivity and activity is largely determined by the nature of the metallic catalyst. However, an equally important role is played by the supports, a variation of which provides not only an increase in the catalyst activity but also an improvement in the on-stream stability of the catalyst. An important role is played by both the chemical nature and the structure and morphology of the support. Using the example of the two processes, it is shown that the catalytic processes in the studied systems have a bifunctional nature. It is shown that the oxide support plays an important role in the water sorption, which accelerates the occurrence of both the steam reforming and electrocatalytic oxidation of alcohols.

Purpose. One of the key characteristics of water quality and marine ecosystems’ sustainability is nutrients supply, which are the main factors of phytoplankton bloom. Since the mid 20th century, in the northwestern Black Sea and on its western shelf, significant changes in nutrients concentrations took place, which were manifested in increase of the inorganic nitrogen and phosphorus concentrations, and decrease of the dissolved silicon content, that in its turn, led to a strong anthropogenic eutrophication of the above-mentioned regions. The aim of the work is to assess the current state of the Black Sea based on the data on the nutrients distribution and dynamics in the surface water layer. Methods and Results. The data obtained in the cruises of R/V “Professor Vodyanitsky” in 2016–2019 were analyzed. The main regions under study included the deep part of the Black Sea, as well as the Crimean and Caucasian sectors of the economic zone of Russia. The data obtained showed significant variability in the nutrients concentration both in the coastal and open areas. Conclusions. A decrease of nutrients concentration in 2016–2019 as compared to that in 2009–2014 was noted, that can indicate a decrease in the eutrophication degree and an improvement of the Black Sea waters quality. Intra-annual variability of the nutrients concentration in the sea surface layer is observed. No pronounced features in spatial variability of the nutrients concentration in this layer were revealed. It is assumed that in the central deep part of the sea, their concentrations are conditioned mainly by the physical processes of water transfer. In addition to physical transport, the increased nutrients concentrations in the coastal areas are, probably, also related to influence of the anthropogenic factor, namely inflow of nutrients from the coastal sources or their formation resulting from the biogeochemical processes which include organic matter.

This review describes the properties of reactive oxygen species that determine their destructive impact on the tissues of animals and plants and also presents the mechanisms of formation of reactive oxygen species in these tissues. The importance of antioxidant protection of hydrophobic zones, first of all, lipid membranes, in living organisms is underlined. Pathological states initiated by violation of the membrane structure and composition, in particular, due to the toxic effect of cholesterol oxidation products are described; data on such states arising from oxidative processes in low-density lipoproteins are provided. The results of application of ubiquinone and plastoquinone derivatives as membrane antioxidants and regulators of the level of reactive oxygen species in tissues are presented. The advantages of natural plastoquinone as a lipid-soluble compound that protects cell components from oxidation are discussed.

This paper presents a study of oxidative dehydrogenation of ethane (ODHE) on nanostructured single-component and multicomponent catalysts based on V5+, Mo5+, and Nb5+ oxides and produced on alumina by molecular layering. It has been shown that the molybdenum-containing catalysts exhibit higher activity for ODHE in both single-component and binary samples and ensure higher ethylene selectivity. We have demonstrated advantages of ODHE on membrane–catalyst systems in the form of asymmetric ceramic tubes, with catalysts placed inside of them. The membrane–catalyst systems produced by molecular layering offer considerably higher activity and selectivity in ODHE.

A brief review of recent scientific publications concerning the steam reforming of methanol in membrane reactors for the production of pure hydrogen is presented. The use of membrane reactors makes it possible to lower the temperature of this process by 100°C, increase the selectivity of the process, and practically eliminate the effect of catalysts’ carbonization. A substantial advantage of the use of membrane reactors is the possibility for removing a stream of high-purity hydrogen from the permeate zone. First of all, this applies to CO impurities, whose presence is critical for the use of hydrogen in low-temperature fuel cells based on proton-conducting membranes. The use of metallic membranes based on Pd makes it possible to directly use the hydrogen produced in the fuel cells.

The viability and state of the prooxidant and antioxidant systems of Plantago major seed progeny from cenopopulations growing for a long time at the East-Ural Radioactive Trace (EURT) has been estimated. Radiation doses of maternal plants have been calculated using our empirical data in ERICA Tool. The absorbed dose rates for plantain in the EURT zone varied from 19 to 157 μGy/h, which is 178–1455 times higher than the background values. These relatively low levels of chronic irradiation did not cause a significant decrease in the survival rate of P. major seed progeny; the rate of root and leaf growth decreased only in seedlings from the most polluted cenopopulation. A prooxidant shift was revealed in seedlings from the EURT zone. Given the same regime of enzyme protection (SOD, CAT, and POX) against active oxygen forms, the average rate of accumulation of secondary products of lipid peroxidation (MDA) was 3.3 times higher in impact samples than in background samples. The level of prooxidant shift in impact samples is not linearly related to dose rates that are classified as low doses.

Spatial variations in the distribution and fluxes of dissolved oxygen and sulfide in bottom sediments of Omega and Sevastopol bays have been studied. The results of analysis reveal that the distribution of dissolved oxygen and sulfide in pore water depends mostly on seasonal variations in the oxygen concentration in bottom water, grain size, the organic carbon content in bottom sediments, and, additionally for Sevastopol Bay, the iron content. The oxygen flux at the bottom of Sevastopol Bay is 20 times larger in winter–spring compared to that of Omega Bay. Anaerobic conditions in Sevastopol Bay sediments are observed much closer to the surface, with their subsequent development in bottom water.

The paper studies the patterns of copper slag mineral phase separation by flotation depending on the modification of the additional BTF series collecting agent (dialkyldithiophosphate derivatives) and the ratio of main and additional collecting agent consumptions. The results of open and locked-cycle laboratory flotation tests are presented, and the effect of pulp pH on copper extraction is observed. The reasons for the copper extraction gain during grinding and subsequent flotation in acidic medium are analyzed. The aggregates of copper and iron sulfides are identified in slags thus proving decoppering effectiveness with a decrease in pH to slightly acidic values due to the active flotation of intergrown pieces of copper-containing phases with iron sulfide (pyrite, pyrrhotine). It is shown that the additional BTF series collecting agent added to the main collecting agent – potassium butyl xanthate – makes it possible to reduce the total consumption of the combined collecting agents while maintaining copper extraction and concentrate quality as compared to the consumption of only xanthate necessary to achieve the same parameters. The best results were achieved with the use of the BTF 1614 reagent in combination with potassium butyl xanthate at the BCC : BTF = 3 : 1 ratio. At an optimum pH = 5,5÷6,8, the increase in copper extraction to the concentrate was 11.13%, and gold and silver extraction increased by 9.68% and 9.93%, respectively.

The catalytic activity of complex phosphates of the NASICON structure (composition Li1 ± xZr2–xMx(P1–хMoхO4)3 and HZr2(PO4)3) with the heterovalent substitution of zirconium for indium and niobium or phosphorus for molybdenum and with a particle size of 50–300 nm is studied in transformations of primary and secondary propanols. Heterovalent doping is shown to be prevalent in its effect on the activity and selectivity of catalysts obtained due to both a change in acidity and the redox properties of compounds. A significant difference in the activities of dehydration and dehydrogenation reactions between primary and secondary alcohols is found which is associated with the steric difficulties of these processes. The conversion of propanol-1 and propanol-2 depending on LiZr2(PO4)3, Li0.5Zr1.5Nb0.5(PO4)3, and HZr2(PO4)3 catalysts results in 100% selectivity according to propene. Doping with indium results in approximately 75% selectivity according to propanal.

The process of oxidative dehydrogenation of ethane (ODE) was carried out in a catalytic membrane reactor-distributor on a Mo-V-Te-Ox catalyst supported on asymmetric ceramic membranes. The obtained results show the obvious advantages of ODE with the use of a membrane system. Application of the membrane approach allows us to use initial gas mixtures with the O2:C2H6 ratios that are unacceptable for safety reasons in conventional reactors. Under optimal process conditions, the conversion of ethane of 70% can be achieved in a membrane reactor while maintaining the ethylene selectivity in the range of 95–98%.

The possibility of ethane/ethylene mixture separation at the passing these gases through polyethylene-graft-sulfonated polystyrene membranes in silver and hydrogen forms has been shown. The results showed that the permeability of ethylene and the value of the separation coefficient increased significantly with increasing relative humidity of the separated gases. It was concluded that in both cases the transfer of ethylene occured in the form of a positively charged complex. The patterns of change in the permeability and separation factor were explained on the basis of the structure of the initial membranes and the solubility of the separated gases in the “phases” forming the membrane.

The hydrochemical parameters’ characteristics of the river Chernaya and some its tributaries are represented based on the results of the observations in 2006–2010. The changes both of water hardness and the level of its contamination with the mineral nitrogen compounds (nitrates, nitrites and ammonium ions) are shown. The results of the investigations testify to rather noticeable anthropogenic effect (increasing at low norm of water content) upon the water chemical composition. The retrospective analysis shows that in the extreme cases mineralization, hardness, calcium and nutrient content levels in the river waters significantly exceed the hygiene and sanitary standards for drinking water. The river Chernaya waters (before the water supplying point) are constantly contaminated with the nutrients and organic matter brought by the tribute Baidarka and the slope drainage waters. Consistency of quality of the flood and low runoff waters inflowing the river Chernaya to the normative standards is assessed. Though water hardness exceeds the standards only in the extreme cases, the present trend towards growth of the river Chernaya water mineralization and contamination with organic matter and nutrients requires systemic solving of environmental problems.

This paper presents a method for measuring the heteroplasmy level of mitochondrial DNA mutations, which is based on real-time PCR using TaqMan fluorescent probes. The method makes it possible to detect the heteroplasmy level of mtDNA mutations and has high accuracy and resolution. It shows significant differences between the parameters of heteroplasmy of patients belonging to different groups by the degree of disease. Application of this method, in particular, to determine the predisposition to atherosclerosis, makes it possible to determine whether the patient belongs to a low-, medium-, or high-risk group of atherosclerosis.

Metal oxide-stabilized zirconia supports (MxZr1-xO2-δ) with different dopants (M = Y, La, Ce) were prepared by coprecipitation method. Bimetallic Cu Ni and Ru Rh catalysts supported on MxZr1-xO2-δ were prepared by the sequential wetness impregnation method, for use in hydrogen production by methanol steam reforming. The effect of the nature and quantity of the dopant cation (M = Y, Ce) on the catalytic performance of zirconia supported metal catalysts was investigated. The activity of Ni Cu/YxZr1-xO2-(x/2) (x = 0.1–0.3) samples increases with an increase in yttrium concentration due to the formation of oxygen vacancies. The dependence of the catalytic activity on the ceria concentration was not monotonous. The sample containing 10% of cerium oxide showed the highest activity. The performance of a Ni Cu/La0·1Zr0,9O1.95 sample was compared with the performance of a Y and Ce containing samples with the same quantity of dopant cation (10%). The La doped catalyst was more active than the yttria-containing composites, but its selectivity was lower. The catalyst based on Ru Rh alloy differed with significantly higher activity and lower selectivity compared with Ni Cu samples. The selectivity of the process was not less than 99.5% for all catalysts even at the high temperatures. At the same time, the improved activity of the catalyst also results in an increase in carbon monoxide formation while the hydrogen selectivity decreases. The optimal characteristics, such as rather high hydrogen yield, good selectivity and stability were shown by the catalyst with Ce0·1Zr0·9O2-δ support.

Results of a study of the methanol steam reforming (MSR) catalytic process in conventional flow and membrane reactors in the presence of Ni0.2–Cu0.8 and Ru0.5–Rh0.5 catalysts supported on ZrO2 with a monoclinic, tetragonal, and cubic structure have been described. The cubic structure of zirconia has been stabilized with ceria. The samples have been characterized by X-ray diffraction analysis, transmission electron microscopy, and the BET method. It has been shown that the catalytic activity of the composites depends on the type of the metals and the structure of the support. It has been found that the Ru–Rh/Ce0.1Zr0.9O2–δ catalyst exhibits the highest activity, whereas Cu–Ni/Ce0.1Zr0.9O2–δ is the most selective. A comparative study of the MSR process in conventional and membrane reactors with Pd–Ru and modified Pd–Ag membranes has been conducted. The membrane process with a membrane based on a Pd–Ag alloy in the presence of the Ru–Rh/Ce0.1Zr0.9O2–δ catalyst provides a ~50% increase in the hydrogen yield.

Catalytic properties of nondoped and copper-doped Mayenite have been studied. During ethanol conversion and ethanol steam reforming, the initial Mayenite and specimens containing 0.58 and 0.92 wt % of copper have been analyzed. All catalysts are active in both processes. The influence of the ethanol/water mole ratio on product distribution has been studied. In the course of experiments, the fact of reversible hydrogen sorption has been detected upon the thermal treatment of catalysts containing copper.