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Extraction processing of pine needles ( Pinus sylvestris Ledeb.) allows obtaining the products that are used to manufacture the goods in medical, food, perfumery and cosmetics, and other branches of industry. At the same time, the post-extraction residue of needles (PERN), being a specific lignocellulose raw material, has not yet found proper (effective) use for obtaining innovative products. Using the method of thermogravimetry in a nitrogen atmosphere (TG/DTG), a number of thermal decomposition patterns of PERN have been established. Based on the results of TG/DTG, the kinetics of PERN pyrolysis was analyzed, the thermodynamic parameters Δ H , Δ G and Δ S were calculated. The average values of Δ H , Δ G and Δ S are 246.3, 160.3 kJ/mol and 135.7 J/(mol · K), respectively. According to the method of the fourth derivative of DTG contour proposed by us, a detailed “fractionality” of mass loss during heating of PERN under the conditions of thermogravimetric test has been established. The values of the apparent rate constant are calculated, indicating the multistage (I-V) process of thermal decomposition. By means of analytical flash pyrolysis of PERN, 66 pyrolysis products were identified. Among them, 35 compounds were identified that are not found in pine bark and wood pyrolyzates and can be in demand in organic synthesis, in the production of technical and food products, perfumes, medical products, etc . The obtained results are basic for designing the manufacture of technical products with increased added value and scaling of heat treatment technologies and pyrolysis of similar plant raw materials.

The influence of various technological additives on the plastic and rheometric properties of a rubber mixture is investigated, physical-mechanical and performance characteristics of rubber based on a combination of SKN 4055 nitrile butadiene caoutchouc and Therban 3406 hydrogenated nitrile butadiene caoutchouc are assessed. The rubber mixture included SKN 4055 and Therban 3406, curing agent Luperox F-40P, antioxidant Diaphene FP, fillers: burnt magnesia, carbon black T 900 and P 514, oligoester acrylates TGM-3, MGF-9, and other ingredients. We used Z-50, Z-60, Struktol WB-222, Kvalistrol A-100, B-70 and B-70-20 as technological additives. The rubber mixture was made on laboratory rolls LB 320 160/160, then vulcanized at 150 °C for 60 min and thermostated at 160 °C for 3 h. Studies of the plastic and rheometric properties of the rubber compound, the physical and mechanical properties of vulcanizates were carried out in accordance with the standards existing for rubber industry. The study of thermo-aggressive resistance of vulcanizates was carried out by determining the change in their physical-mechanical parameters after 1 day exposure to air and standard liquid SZhR-1 at a temperature of 150 °C. It is found that the introduction of technological additives leads to improvement in the distribution of ingredients, as well as in the plastoelastic and rheometric properties of the rubber mixture. Rubber containing Kvalistrol B-70-20 has increased physical and mechanical properties, exhibiting the least changes after exposure to aggressive media.

The content of 25 chemical elements was determined quantitatively, by means of mass spectrometry and atomic emission with inductively coupled plasma, in natural spring sources, as well as in water from central utility and drinking water supply systems and secondary water purification systems (household filters) for the purpose of exploring the safety of drinkable water for the population of some districts of the Magadan Region. Conformity of chemical element concentrations to the standard quality requirements for drinkable water was determined. The study confirms that water is safe for human consumption with respect to the accumulation of conventionally essential and toxic chemical elements. However, water tests showed poor saturation with physiologically useful elements at all sampling sites in the towns and settlements of the Magadan Region.

Results of the application of benzene oxidation product (BOP), formed in barrier discharge, as an improving component of the inhibiting additive for paraffinic and highly paraffinic petroleum are presented. The proposed additive consists of a copolymer of alkyl acrylates with dodecylamine acrylate and BOP at a ratio of 15:1 wt. %. Benzene oxidation by air in a barrier discharge proceeds predominantly to phenol (~77.3 wt. %), diatomic phenols, and an insignificant amount of macromolecular compounds. The effect of the additive (in combination with BOP) in the amount of 0.03-0.05 wt. was evaluated relying on changes in the rheological characteristics and freezing point of paraffinic and highly paraffinic petroleum with a high content of resins and asphaltene components. The composition containing polymer and BOP additionally reduces the amount of asphaltene-resin-paraffin deposits by 1.5-2.5 g, which gives an increase in inhibitory capacity by 10-12 %. The depression of the freezing point of petroleum is 46 ºС on average. The dynamic viscosity of petroleum under study decreases in the presence of the additive by a factor of 2.2 on average.

The effect of basalt fibres on the rheometric, physical-mechanical, performance and dynamic (vibration absorbing) properties of rubber used for rail fastenings is investigated. The rubber mixture based on butadiene-methylstyrene (SKMS-30ARK), isoprene (SKI-3) and butadiene-nitrile (SKN 2655) caoutchoucs contained also vulcanising agents (sulphur, N,N′ -dithiodimorpholine, tetramethylthiuram disulphide), vulcanisation accelerator ( N-cyclohexyl-2-benzothiazole sulphenamide), vulcanisation activators (zinc oxide, stearic acid), softeners (industrial oil I-12A, rosin), antioxidants ( N-phenyl- N'-isopropyl-para-phenylenediamine, wax ZV-P, acetonanil N), fillers (kaolin, carbon black of N 220 and P 514 grades, silicon dioxide Zeosil 1165 MP) and other ingredients. The strength properties and hardness of the vulcanisates are observed to increase with an increase in the content of basalt fibres in the rubber mixture. Basalt fibres reduce changes in the elastic-strength parameters of vulcanisates after daily thermal aging in air and under the action of the standard petroleum fluid SZhR-1. The improved dynamic (vibration damping) properties are exhibited by vulcanised rubber containing 12.0 phr basalt fibres.

Based on the results of adsorption studies, a procedure for modifying the porous carbon sorbent with tributyrin has been developed. The synthesis of tributyrin and the procedure of its quantitative determination in ethanol solutions by means of spectrophotometry are described. Carbon sorbent samples modified with tributyrin were obtained. Their properties have been studied using a complex of physicochemical methods. The possibility of using the modified sorbent as a drug of prolonged action is studied: tributyrin desorption from the carbon sorbent under model conditions in contact with 0.9 % NaCl (physiological solution) and in ethanol is investigated. It is established that in contact with the test solutions, the modifier deposited on the carbon carrier is desorbed within 6 h.

The dispersed fractions of industrial high-calcium fly ash (HCFA), selectively collected in the form of fractions 1-4 (Fr1-Fr4) on fields 1-4 of the electrostatic precipitators of the ash collecting unit at the Krasnoyarsk TPP-2, are systematically characterized. The fluidity parameters of ash mortars prepared from 100 % of each of the fractions at a ratio of water/binder = 0.5 were determined. It has been established that the value of fluidity decreases with an increase in the specific surface area of the fractions from Fr1 to Fr4. The parameters of cement-ash mortars with the replacement of cement by 50 and 20 % of each of the four fractions were determined. It has been established that at a 20 % HCFA content, the fluidity of cement-ash mortars of all fractions meets the requirements of GOST 1581-2019 for oil well cements. The samples based on finely dispersed fractions Fr3 and Fr4 meet the requirements for compressive strength on the second day of hardening. The specimens of ash-cement composites with high strength, more than 50 MPa for the 28th day of hardening, were prepared on the basis of the Fr4 fraction. In particular, high compressive strength (62-90 MPa) has been achieved for composite cements containing 80 and 90 % of the Fr4 fraction of HCFA in the presence of the superplasticizer Melflux 5581 F, which promotes efficient dispersion of finely dispersed HCFA in the liquid phase, faster and more complete interaction of active components with the formation of hardening hydrated phases. The addition of 5 % microsilica, which promotes the formation of an additional amount of calcium hydrosilicates, made it possible to achieve an increase in strength up to 108 MPa. The results obtained show that finely dispersed HCFA can be used as the components of oil well cements to improve the flowability of cement-ash slurries and improve the strength properties of highly filled ash-cement composite materials.

It is shown that the yield of humic acids increases by 20-30 % during the mechanical treatment of coals with a complex of oxidative-alkaline reagents. Upon the mechanochemical oxidation of the organic matter of brown coals, the molecular weight of humic acids and the percentage of aliphatic fragments in their structure decrease, while the content of phenolic and carboxyl groups increases. Ion exchange processes during the mechanical treatment of coals with mineral salts are accompanied by a decrease in the content of Na⁺ cations and an increase in Ca²⁺, Mg²⁺ cations in the composition of water-soluble humic substances. The concentration of SO₄^2- ions increases in samples of humic substances obtained from coals after mechanical treatment with ammonium sulphate.

The effect of leuzea (Rhaponticum carthamoides) and cranberry (Vaccinium oxycoccus) meal extracts composition at a dose of (70 + 500) mg/kg, as well as individual active substances (ecdisten and ursolic acid) in equivalent doses, on the biochemical parameters of physical endurance (lactate, glucose) in the forced swim test on CD-1 male mice is investigated. It has been established that the developed composition exhibits pharmacological effects similar to those of the individual active substances promoting a decrease in the concentration of glucose (in blood) and lactate (in blood and in muscles).

Copolymer of 2-(4-acryloylpiperazin-1-yl)methyl)-9H-thioxanthen-9-one and methyl methacrylate was synthesized by radical polymerization. This copolymer has high molecular weight characteristics and is capable of forming long-lived anion radical states of the pendant thioxanthenone groups during electrochemical reduction. Using a combination of electrochemical and optical methods, it has been shown that the electronic states of the pendant groups are located within the band gap of methyl methacrylate and may promote the Frenkel mechanism of conductivity in dielectric thin films used in resistive memory devices.