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A compacted matrix of boron carbide has been infiltrated by molten aluminum. It is shown that under the external mechanical action on aluminium, presumably simplifying the destruction of oxide film on molten metal, the temperature of boron carbide wetting decreases from 1100-1200 to 830-850 °C, and this prevents the formation of unfavourable aluminium carbide that could worsen the mechanical properties of composite material. Dense ceramic composites with the density within the range of 2.45-2.58 g/cm³, Vickers hardness up to 21 GPa and fracture toughness at a level of 3.5-4.5 MPa · m^1/2 have been obtained. It has also been determined that, although carbon nanotubes react with molten aluminium, a considerable amount of them is preserved during infiltration at temperatures below 950°С, which allows one to synthesise the соmposite material reinforced with nanotubes.

A technology for thermolytic processing of fuel oil over a tin-lead melt in a flow-type reactor is proposed. Methods for fuel oil processing at oil refineries are currently too complicated and cost-demanding, so the development of effective technologies for fuel oil processing is an urgent task. The main advantages of the proposed technology are rather low process temperature and pressure close to atmospheric. The technological parameters of the process are constant over all points of the reactor, which ensures high-quality products. The formation of carbon deposits on the reactor walls is essentially eliminated. The technological process occurs simultaneously with auxiliary and transport operations, which increases the productivity of the installation. It becomes possible to completely automate technological process, eliminating the use of manual labour and simplifying installation maintenance. A schematic diagram of the flow-type installation is presented. The results of experiments on the thermal cracking of fuel oil over a tin-lead melt, carried out using two versions of destructive distillation, are presented. The first version involves minimal withdrawal of thermal gas oil (31 %), while in the second version it is maximal (77 %). It has been shown that the content of gasoline fraction (b.p.-180 °С, where b.p. is initial boiling point) and diesel fraction (180-360 °С) in the thermal gas oil obtained according to the second version is lower than that obtained according to the first version. Thermal gas oils have a high content of aromatic compounds, which makes them a promising raw material for the production of needle coke.

The modern market of paint and varnish materials is represented by a wide range of construction products, including those designed to protect facades of buildings and structures from atmospheric impact. Among the variety of varnishes and paints for processing and rendering decorative and protective properties to building materials, as well as from the viewpoint of environmental friendliness, the most popular products are water-dispersion paints based on acrylic dispersions. However, along with the high values of colour fastness, UV resistance and gas permeability, acrylic-based paints are insufficiently elastic and lack resistance to water. In this regard, the paper considers a method for increasing the mechanical and hydrophobic properties of acrylic paint and varnish material by introducing a hydrophobic polyethylhydrosiloxane-based emulsion containing polyethylhydrosiloxane (PEHS) - 35.20, glutaric aldehyde - 0.19, polyvinyl alcohol (PVA) - 7.75, water - 56.86 wt%, as well as by increasing the surface development (relief), achieved by increasing the volumetric concentration of pigments (VCP). The optimal range of the amounts of a hydrophobic emulsion and a coalescent into the composition of water-dispersion paints based on acrylic dispersion has been determined. To assess the stability of the coating after drying of an aqueous dispersion paint modified with the aqueous polyethylhydrosiloxane emulsion, the wetting angle and free energy of the surface were evaluated using two liquids of different polarities, namely distilled water and diiodomethane. The possibility of modifying the aqueous dispersion paint, characterised by VCP of 70-80 %, by the polyethylhydrosiloxane hydrophobic aqueous emulsion in the amount of 5-5.5 %, combined with ethylene glycol (4.5-5.5 %) has been established, which makes it possible to obtain a hydrophobic coating with a wetting angle of up to 100°. By comparing the wetting angle values of the coatings, it has been shown that in the absence of the hydrophobic additive, this parameter is lower by 12.5 % than the parameter of the modified sample.

Despite the increasing contribution of integrated approaches to processing waste from the forest industry and crop production, the main method of recycling plant wastes is still combustion, which leads to losses of valuable substances. An alternative and advanced way of plant waste processing is extraction to obtain useful substances. The previously published data on the extraction-based methods to isolate valuable substances from wood waste and straw of various crops under industrial and laboratory conditions are generalised in this work. The data on the chemical composition of wastes from forest industry and crop production, as well as on the content of chemical compounds of practical significance are systematised. The basic approaches to retrieve such valuable components as lignin, furfural, waxes, organic acids, polyphenols, dyes, silicon dioxide and others from plant wastes are described.

The electronic effects of xenon-containing substituents XeY, [Xe⁺] and [XeF₂⁺] in different solvents were calculated using the ¹⁹F NMR method. The results obtained allow us to classify these substituents as the strongest σ-electron acceptors due to the strong positive inductive effect, while the resonance effect is small.

2,5,5-Triethyl-2-alkynyl-3,4-bis(hydroxymethyl)pyrrolidine-1-oxyls (alkynyl = C≡CR, and R = H (2), C(Me)₂OH (1), Ph (7)) undergo cyclisation on heating with sodium hydroxide to form cyclic vinyl ethers, the derivatives of 6-methylene-hexahydro-1 H -furo[3,4-b]pyrrole-1-oxyl. A bicyclic radical derived from radicals 1 or 2 is capable of reversible addition of alcohols to the vinyl group in the presence of acids. Cyclisation of radical 7 in the acid environment in the presence of mercury acetate follows a different route, with the formation of 2,2,7a-triethyl-3-(hydroxymethyl)-6-phenyl-1,2,3,3a,4,7a-hexahydropyrano[4,3-b]pyrrole-1-oxyl.

Aldonitrones of pyrroline series are widely used in organic synthesis, in particular in the synthesis of alkaloids and other biologically active compounds, and as spin traps for short-lived radicals. A three-component domino process involving glycine benzyl ester, ketones (cyclohexanone and diethyl ketone) and fumaric acid esters was used to synthesise aldonitrones of the pyrroline series of 1-pyrroline-1-oxide. The benzyl esters of 3,4,5-substituted prolines obtained in the first step were selectively cleaved by hydrogenolysis. Oxidation of the resulting cyclic amino acids in the tungstate - hydrogen peroxide system is accompanied by decarboxylation and leads to the formation of 3,4,5-substituted 1-pyrroline-1-oxides. It is shown that the ester groups in these compounds can be reduced to hydroxymethyl ones by an excess of lithium aluminum hydride, and subsequent treatment with manganese dioxide leads to aldonitrone group recovery.

An optimised method of 1,1-difluoronaphthalen-2(1H)-one hydrodefluorination leading to the formation of fluoronaphthol under mild conditions is proposed. The palladium-catalysed process is shown to involve carbonyl reduction followed by subsequent hydrogen fluoride (HF) elimination. The structure of the intermediate product and the effect of catalyst support material on hydrodefluorination selectivity have been determined.

Chelators based on terpene bis(α-amine oximes) applied onto low-polar sorbents (coal, Sibunit, Polysorb) are effective selective extractants for the extraction of palladium and gold from acidic aqueous solutions containing the mixtures of precious metals and 3 d-elements. The use of sorbents impregnated with the new chelators allows extraction in the liquid-solid mode without using any organic solvent.

The composition of the lipophilic components of Euphorbia virgata Waldst. et Kit. has been studied. Acidic and neutral components have been identified using gas-liquid chromatography with mass spectrometric detection (GC-MS) following alkaline hydrolysis of the whole extract. The plant material was extracted with methyl tert -butyl ether (MTBE). Total acids isolated during sample preparation were analysed after methylation with diazomethane. The composition of the neutral components of unsaponifiable residue was studied without derivatisation, but after separation by column chromatography on silica gel into the groups of substances of different polarity. As a result, aliphatic acids with the chain length 10-30 carbon atoms, including unsaturated ones, were identified by comparison with databases. In addition, two compounds rarely occurring in plant materials were detected: ricinoleic and octadeca-9-en-12-ynic acids. More than 100 triterpene and aliphatic compounds of the unsaponifiable residue and 25 components of acidic fractions were identified. The hydrocarbon fraction was determined to contain, in addition to n- alkanes, also substantial amounts of unsaturated branched hydrocarbon squalene. Highly active triterpene alcohols and ketones are mainly represented by ursane, lupane and cycloartane derivatives. The main sterol component (β-sitosterol) is accompanied by cholesterol, campesterol, stigmasterol, stigmast-7-en-3-β-ol and stigmastan-3-β-ol. A substantial contribution from euphanic compounds characteristic of the plants of the Euphorbiaceae family has been revealed.