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Compositions for the formation of three-component elastic cryogels based on the aqueous solutions of polyvinyl alcohol (PVA) and potato starch are proposed. It is shown that the viscosity of aqueous solutions depends both on the kind of polymer and on the total content of polymers in the system. The elasticity modulus of three-component cryogels depends on the concentration of starch in them and increases from 5 to 15 kPa with the addition of starch in the amount of 1-5 wt%. By introducing a dispersed material (soil) into the matrix of two-and three-component cryogels, due to the high adhesion of the polymer to the filler, the filled cryogels were obtained, with the elasticity modulus 16 times higher than that of cryogels without the filler. The introduction of potato starch in the amount of 5 wt% into PVA cryogel caused an increase in the time of its complete drying by 24 h, and an increase in its destruction during exposure in water by 5% within a week. Two-component cryogels exhibited sharply different types of behaviour during storage in water: PVA cryogel did not lose its mass, while mass loss by the cryogel of potato starch was 11% within a week. A decrease in the mass of three-component cryogels by 75-89% due to the loss of moisture and destruction was demonstrated in the soil test under the action of aboriginal soil microflora. The mass loss by the two-component cryogel based on PVA was 60%. Soil testing for phytotoxicity after the destruction of three-component cryogels revealed a decrease in the germination capacity of white mustard ( Sinapis alba L.) by 2-10% with respect to the reference experiment, depending on starch content, while for the reference two-component PVA cryogel the corresponding decrease was by 18%. Cryostructuring of the upper soil layer by PVA cryogel caused an increase in the dry above-ground mass of plants by 3.2% in comparison with the reference, while the cryogel with potato starch caused an increase by 7.1%, and cryogel based on PVA and potato starch gave 9.4%.

Methanation process, or selective hydrogenation of carbon oxides, is described. The chemical foundations of the process and the features of the formation of reaction products are considered, depending on the catalyst used. The advantages of catalytic systems based on carbon materials and disadvantages of the catalysts on oxide substrates for the production of synthetic methane are evaluated. Nickel-containing carbon catalysts based on birch activated carbon and microcellulose were obtained by incipient wetness impregnation and hydrothermal synthesis, and proposed for the selective hydrogenation of carbon monoxide (СО). The synthesized samples were studied by optical emission spectroscopy with inductively coupled plasma, low-temperature nitrogen adsorption, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, thermogravimetric analysis. The influence of the substrate and the method of catalyst synthesis on CO conversion and methane yield from the selective hydrogenation of CO was studied, and the optimal size of NiO and Ni(OH)₂ crystallites, the precursors or the active phase, was determined. It is shown that the best carbon monoxide conversion and methane yield from methanation reaction are achieved in the presence of nickel-containing microcellulose-based carbon sample obtained by hydrothermal synthesis.

An algorithm is presented for identifying potential production chains for resource-based regions relying on patent analytics, in particular, applying patent landscape report creation approaches and peer review, which in the future, after their economic justification, can become the foundation for the new strategy of innovative development for a resource-based region. Within this strategy, it is planned to create new high-tech economy sectors in the field of coal mining and coal processing.

1-(Pentafluorophenyl)propan-1-one reacts with zinc in the presence of catalytic amounts of SnCl₂ under heating in dimethyl formamide to give (2,3,5,6-tetrafluoro-4-propionylphenyl)zinc chloride and bis(2,3,5,6-tetrafluoro-4-propionylphenyl)zinc. 1,1'-(2,3,5,6-Tetrafluoro-1,4-phenylene)dipropan-1-one was synthesized from these organozinc compounds and propionyl chloride in the presence of CuI. The reaction of organozinc compounds obtained from 3-bromo-1,2,4,5-tetrafluorobenzene leads to the formation of 1-(2,3,5,6-tetrafluorophenyl)propan-1-one

The interaction of alkyl(4-X-2,3,5,6-tetrafluorophenyl)sulphanes (X = H, CF₃) containing difluoromethyl and benzyl groups as alkyl components with hydrogen peroxide in acetic or trifluoroacetic acid gave the corresponding sulphonyl derivatives. The effect of the acid used on the reaction result was established in the case of (difluoromethyl)[4-(trifluoromethyl)-2,3,5,6-tetrafluorophenyl]sulphane. The synthesis of 1-alkylsulphonyl-2,3,5,6-tetrafluorobenzenes scaling possibility to tens of grams was demonstrated. Product yields were 84-97%.

The synthesis of urea and thiourea containing adamantane and campholene fragments was performed starting from adamant-1-yl isocyanate, adamant-1-yl isothiocyanate and campholenyl amine. The synthesised compounds were modified to their oxalyl derivatives, which may be of interest for biological activity screening.

Drew-Dickerson Dodecamer (DDD) is one of the well-known DNA duplexes. It has been sufficiently well studied by various structure determination methods and appears to be a standard for developing new experimental techniques and molecular mechanical force fields. For this reason, the information about the dynamics of DDD on different time scales is important for constructing more accurate structural-dynamic models and carrying out molecular dynamics calculations of long-term time trajectories that allow simulation of real processes. In this work, the information on the dynamics of DDD base pairs on the milli- and microsecond time scale, currently missing from the literature, was obtained by means of imino protons’ nuclear spin relaxation ( R_1ρ) dispersion. It is shown for all the base-pairs, except for terminal and pre-terminal ones, that any dynamic processes in the range of R_1ρ method are not observed up to 300 K, but proceed on a faster time scale. For the pre-terminal GC pair, a pronounced dependence of the relaxation R_1ρ on the applied spin-lock field strength is observed, which allowed us to extract the information about the pair closing dynamics using a fast exchange model with highly skewed state populations. These data supplement the information obtained previously on the dynamics of DDD complementary base pairs by exchange-based water magnetization transfer experiments and provide a more complete view of the processes observed in DDD in relation to base pair opening-closing.

In the recent years, triarylmethyl radicals are widely used as spin probes and tags, so the study of their properties is of great interest. In the present work, the magnetic resonance properties of triarylmethyl radicals (FT (Finland trityl) and OX063) labeled with ¹³C isotope in water-glycerol and water-trehalose solutions are studied using stationary and pulsed EPR within a wide temperature range. Their magnetic resonance parameters, electron spin relaxation times and rotation correlation times at different temperatures are measured. It is shown that ¹³С-FT radical forms aggregates in trehalose solution, while aggregates are not observed for ¹³С-OX063 radical.

The condensates obtained during wood drying are dilute aqueous solutions of volatile substances and are the closest in their properties to widely known hydrolates. The analysis of the composition of hydrolates is often carried out using their preliminary extraction with organic solvents. However, some hydrophilic compounds may be lost during this procedure, so that analysis results might not correspond to the native composition of the hydrolate. In this work, we have developed a modified technique of GLC analysis with preliminary sample preparation, including the extraction of condensate with an organic solvent, by using an internal standard of hydrophobic nature in the analysis. The developed technique has been tested on hydrolates of ordinary pine wood ( Pinus sylvestris var. mongolica Litv.), but it can also be applied both to condensates obtained during drying of other wood materials and other plant material, and to hydrolates.

The interaction of 4,6-difluoro-, 4-fluoro-, and 2-bromo-4,6-difluorobenzothiazole with BuLi or LiN[(CH₃)₃Si]₂ in tetrahydrofurane, followed by the treatment with dimethylformamide and MeI, revealed the main metalation sites in these model mono- and difluorinated benzothiazoles. The reactivity of the resulting Li-derivatives with respect to formylation and methylation was also characterized.