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Three midocean ridges meet in the Bouvet triple-junction region: Mid-Atlantic, Southwest Indian, and American-Antarctic. The triple-junction region is indicated by the Bouvet hotspot magmatism. Available laboratory modeling data are applied to construct a diagram showing the conduit of a thermochemical mantle plume melting from the core-mantle boundary and erupting onto the surface. Morphobathymetric data for the Bouvet Island region are used to obtain the mass flow rate of magmatic melt for the Bouvet plume. Considering the calculated melt flow rate, the thermal power of the Bouvet plume source is N _B = (1.7-2.0) ·10¹⁰ W, and the plume conduit diameter is 9-16 km. Possible evolution of the Bouvet plume is presented on the basis of consideration of its geodynamic regime. The influence of the geodynamic system of asthenospheric convection flows on the ocean floor structure in the Bouvet region is shown. The plume under whose influence Bouvet Island formed is located in the region of the ascending asthenospheric roll flow and locally intensifies it. Transform faults in the Bouvet region were formed under the influence of descending asthenospheric roll flows. The width and the depth of the trough of the Bouvet transform fault are determined by analyzing the flow structure and heat transfer in the asthenosphere in the Bouvet region and with regard to the intensifying effect of the Bouvet plume on the ascending asthenospheric roll flow. The conducted geochemical and thermobarogeochemical studies indicate the decisive role of fluid components in the magmatic systems of the Bouvet hotspot, which are characterized by enrichment in volatiles (H₂, H₂O, and CO₂) and alkalis (primarily potassium) as well as lithophile rare and rare-earth elements (La, Ce, Th, Nb, and Rb). In view of the seismic tomography results, the features of the mantle structure in the triple-junction region are considered. A high-velocity anomaly is identified along the axial zone of the Bouvet transform fault, and the roots of this anomaly in the upper mantle are traced to a depth of 250 km. A low-velocity anomaly is revealed under Bouvet Island, which is traced to about 500-km depths.

The anthropogenic emission of greenhouse gases, mainly carbon dioxide (CO₂), is considered as one of the main causes of global climate change. The transport sector is one of the largest emitters of carbon dioxide (accounting for more than 20 % of all CO₂ emissions), therefore, reducing the carbon footprint of vehicles should be considered one of the main directions of technological decarbonisation. It is shown in the article that the CO₂ emissions of motor gasoline significantly depend on the component composition of commercial gasoline. Calculations of specific CO₂ emission from the combustion of high-octane components of motor gasoline, namely reformate and isomerisate, were carried out. It is shown that for reformate, the specific emission of CO₂ per 1 t of reformate and per unit energy released is higher by 6.0 and 13.4 %, respectively, than the values for isomerisate. It is shown that the main reason for large specific CO₂ emissions for reformate is the high content of aromatic hydrocarbons in it. Moreover, unlike for paraffinic hydrocarbons, the lower is the molecular weight of aromatic compounds, the higher are specific CO₂ emissions. The presented results can be used to implement the transition to the low-carbon model for the development of the transport sector by utilising more environmental-friendly kinds of fuel through modifying its composition. These approaches do not require changing the design of internal combustion engines or introducing new infrastructure, as in the case, for example, of using engines powered by pure hydrogen.

Steam and steam-air reforming of butanol allows obtaining synthesis gas that can be used as a feedstock in a number of chemical applications or as a fuel for solid oxide fuel cells. The efficiency of these reactions is largely determined by heat transfer. In the case of steam reforming of methane, which is an endothermic reaction, it is necessary to provide heat transfer from the reactor walls into the catalyst layer. During steam-air conversion, which is a thermoneutral or weakly exothermic reaction, local overheating occurs in the front layer, the thermal effect of which must be redistributed over the catalyst layer to compensate for the endothermic effect prevailing in the tail section. To increase heat transfer, structured catalysts based on heat-conducting substrates, namely metal meshes, are used in this work. Such catalysts are a complex composite material with a multi-level structure: structured metal substrate - structural oxide component - active oxide - nanoparticles of metals or alloys, which combines the functions of a heat exchanger, a flow distributor and the catalyst itself. This allows you to control heat and mass transfer, regulate gas-dynamic resistance in the reactor and optimise the amount of catalytic material. In this work, the results of the preparation and study of the physicochemical and catalytic properties of Pt, Rh, Pd, Ru, Ni-containing structured catalysts supported on a fechral (FeCrAl) mesh support are presented. The prepared structured catalysts were tested in the reactions of steam and autothermal conversion of n-butanol into synthesis gas. The highest activity in these reactions was shown by the rhodium structural catalyst. Short-term laboratory resource tests for 15 h did not reveal the presence of soot on the surface of the catalyst, and the composition of the reaction products was close to thermodynamic equilibrium. This catalyst can be recommended for use in reformers for steam and steam-air conversion of butanol-1 to produce synthesis gas.

The possibility of obtaining benzocaine succinamide under the conditions of mechanochemical reaction of succinic anhydride with benzocaine (a local anesthetic) is demonstrated. It has been established that mechanical treatment in a ball mill results in amorphisation of initial substances, promoting adsorption of succinic anhydride on the surface of drug crystals, which leads to the chemical interaction between initial components. An intensive development of solid-phase interaction was determined to proceed intensively during 10 days after the load was removed. The maximum transformation degree (~90 %) was detected for the mechanical treatment of an equimolar mixture of benzocaine and succinic anhydride, in the amount of 4 g, in a ball mill for ~2 h. With a decrease in the mixture mass or increase in the load applied, the maximum yield is achieved within a shorter time. The conversion degree was determined to decrease with an increase in the time of mechanical action in all cases. The detected feature can be related to the equilibrium amidation under the conditions of heating during the long-term action of the impact load.

High-temperature studies of the structure of a composite material with the composition La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ-Ce_0.8Sm_0.2O_2-δ (LSCF64-SDC) have been carried out, and the oxygen permeability of microtubular membranes based on it was investigated. The phase composition of LSCF64-SDC composite was analysed using in situ high-temperature X-ray diffraction. It has been determined that at 700 °C under vacuum conditions, a structural transition to the high-temperature cubic phase occurs in LSCF64 oxide. The dependence of the oxygen permeability of microtubular membranes based on LSCF64-SDC on the partial pressure of oxygen and temperature has been established. The effective activation energy of the oxygen transport process was calculated. The effect of the CO₂ atmosphere on the values of oxygen flows through the microtubular membranes based on LSCF64-SDC was studied.

Quantum chemical simulation of the adsorption of phenylethanol on a tetrahedral Au₂₀ cluster was carried out using the density functional theory, DFT/B3LYP/LANL2DZ. It has been shown that gold atoms located at the top of the cluster have the highest activity in the adsorption of alcohol. Possible reactions of phenylethanol on Au₂₀ cluster to form phenylacetaldehyde were studied. Based on the calculated thermodynamic and kinetic values, it is concluded that the transformation proceeds predominantly through the metal hydride mechanism.

The proportion of hard-to-recover oil reserves in the world and in Russia is constantly growing. The development of hard-to-recover reserves, including high-viscosity oil deposits, low-permeability reservoirs, and difficult production conditions, such as the Arctic, is becoming an increasingly important factor in maintaining high levels of oil production. For the effective development of hard-to-recover reserves, physicochemical and complex technologies for increasing oil recovery have been developed at the Institute of Petroleum Chemistry SB RAS on the principles of green chemistry, buffer self-regulating systems and the method of deep eutectic solvents (DESs) using the smart compositions of surfactants, coordinating solvents, and complex compounds. The compositions chemically evolve in the reservoir with the acquisition and long-term preservation of colloidal chemical properties that are optimal for oil displacement. Factors causing chemical evolution include thermobaric reservoir conditions, interaction with reservoir rock and reservoir fluids. The review presents the fundamental and applied aspects of the physicochemical and complex methods for increasing oil recovery, developed at the Institute of Petroleum Chemistry SB RAS, the results of laboratory studies, field tests and industrial use of technologies for increasing oil recovery from the oilfields with hard-to-recover reserves under natural development mode and thermal steam influence, including the deposits of high-viscosity oils. Technologies are environmentally friendly and technologically efficient. To implement the technologies, acid and alkaline oil-displacing compositions based on surfactants and buffer systems with adjustable viscosity and high oil-displacing ability have been developed. The results of laboratory studies of phase equilibria, physicochemical, acid-base and rheological properties in surfactant - DES systems containing polybasic acid, polyols, urea, aluminium and ammonium salts are presented. The developed compositions possess the following advantages: they are compatible with formation waters, low-freezing ((-20)-(-60) °С) or solid, have low interfacial tension at the boundary with oil, applicable in a wide temperature range (10-200 °C). The industrial use of these technologies will make it possible to extend the profitable operation of fields with hard-to-recover oil in a wide range of climatic conditions, including the Arctic.

Development and operation of wells at oil and gas fields are often accompanied by unexpected complications related to drilling mud loss and breakthrough of gas and fluids through reservoir fractures, which requires repair and insulation operations (RIO) to be performed with adequate quality. The ways to improve the efficiency of repair and insulation operations in oil and gas wells with the use of gel-forming plugging materials are considered in the work. The use of various hydrophilic and hydrophobic dispersed and fibrous fillers in hydrogels based on polyacrylamide and complex organic crosslinker is proposed in order to improve their rheological properties and increase the blocking ability. Such organic-inorganic composites show a variety of rheological properties, which makes it possible to select the necessary hydrogel compositions for certain RIO. The results of rheological (oscillation) and filtration studies, as well as field tests of the compositions, are presented. Chrysotile, carbon black, hydrophilic nanosilica, and mechanically activated wood flour, rice husk, hydrolysed lignin were used as dispersed fillers in oscillation studies. Polypropylene fibres, basalt fibres and carbon fibres were considered as fibre fillers. The values of elastic modulus (G') and viscosity modulus (G''), crossover points and linear viscoelastic regions for each composition were determined from the results of oscillation studies. An increase in the modulus of elasticity up to 48 % (G' = 53.3 Pa) was achieved with the addition of carbon black and up to 50 % (G' = 54.2 Pa) for the composition with chrysotile and carbon fibre, compared to the base hydrogel without fillers (G' = 36.1 Pa). The addition of hydrophilic nanosilica allowed an increase in the yield strength (crossover point) by more than 300 % (to 210.4 Pa). Filtration studies were performed on the ideal fracture model with different opening (50, 100, 650 mm) using natural core samples. It has been established that during water filtration the hydrogel with chrysotile and polypropylene fibre additives has a higher residual resistance factor (RRF = 167) in the fracture with 100 μm opening than the base hydrogel (RRF = 136) in the 50 μm fracture. When blocking a gas-saturated model of an ideal fracture, the maximum RRF was 2677. Field tests of the composition with dispersed and fibre fillers for elimination of catastrophic drilling mud circulation loss and RIO were successful.

The paper presents the results of studies of natural gas hydrates in water-in-oil and water-in-asphaltene-resin-paraffin deposits (ARPD) emulsions conducted in the laboratory of technogenic gas hydrates of the Institute of Oil and Gas Problems, SB RAS. The kinetic aspects of the hydrate formation process in the selected emulsions, the prevailing mechanisms of hydrate crystals formation, the effect of the medium on the morphology of the formed hydrates are described in detail. The study of gas hydrates growth was carried out using the differential scanning calorimetry (DSC), as well as synthesis in a special high-pressure chamber.

Development of high-tech methods for utilization of lignins produced in a huge amounts in the industry of lignicellulosic biomass processing is the urgent task. The present paper describes the new promising methods of wood lignins valorization to valuable chemical products, developed in the Institute of Chemistry and Chemical Technology SB RAS, FRC KSC SB RAS. Aromatic aldehydes and organic acids were obtained by catalytic oxidation of lignins by oxygen and hydrogen peroxide, liquid hydrocarbons - by catalytic conversion of lignins in supercritical alcohols. In the medium of supercritical ethanol the high yield of liquid products from lignin has been achieved in the presence of solid catalysts based on sulfated ZrO₂ and on high-silica zeolites in H-form. In the medium of supercritical butanol the high activity in the conversion of lignin to liquid products has been shown by supported on SiO₂ nickel-containing catalysts. New methods of synthesis of nanoporous carbons from lignin including carbon molecular sieves and aerogels with unique properties were developed. It was shown, that thermal alkaline activation of lignin promotes the formation of cabon materials with specific surface area up to 2700 m²/g and total pore volume up to 1.4 cm³/g. Obtained nanoporous carbon materials show a high sorption activity and have the prospects of their use for separation of gaseous mixtures and for purification of gases and water. The methods of synthesis of nanoporous organic and carbon aerogels on the basis of inexpective lignin- containing mixtures: lignin-tanin-formaldehyde and lignin-phenol-formaldehyde were suggested. Obtained aerogels have a broad potential applications as thermo-insulating materials, sorbents, catalysts, electrodes, electrochemical capacitors.