Sr_1-xGd_xFe_12-xCo_xO₁₉ (x = 0; 0,1; 0,2; 0,3; 0,4; 0,5) ferrites have been prepared by solid-state method in air at 1473 K. XRD has shown that samples with x ≥ 0,2 contained not only main phase with the magnetplumbite structure, but also the a-Fe₂O₃ and Gd₃Fe₅O₁₂ phases. There were GdFeO₃ and CoFe₂O₄ phases present in the samples with x = 0,3; 0,4; 0,5, samples with x = 0,4; 0,5 also contained Gd₂O₃ phase. It has been found that the conductivity activation energy for Sr_1-xGd_xFe_12-xCo_xO₁₉ (x = 0-0,4) ferrites at temperatures above the T_frac 1næ dependence of T^-1 is 0,13-0,18 eV higher than the activation energy in the temperature range below the T_frac. The coefficient of linear thermal expansion (a) for Sr_1-xSmGd_xFe_12-xCo_xO₁₉ ferrites changes slightly in the x range from 1,13^.10^-5 K^-1 to 1,27^.10^-5 K^-1.

The sensitivity of nanocomposites In₂O₃:Ga₂O₃ (98:2, 96:4, 92:8 wt.%), both pure and doped with Fe₂O₃ (0,5-10 wt.%), has been investigated. Nanocomposites In₂O₃:Ga₂O₃ have been obtained by the sol-gel method, Fe₂O₃ has been obtained by various methods of Fe (II) and Fe (III) salts deposition. Standart gas mixtures contained 5000 ppm CH₄ in air, 5000 ppm CO in air, as well as 2 and 10 ppm NO₂ in nitrogen. The possibility of selective detection of NO₂ over CH₄, CO, ethanol vapor and other volatile organic compounds at low sensor power consumption (200 mW) has been established.

It has been shown that improvement of steric accessibility of the higher quaternary ammonium salts exchange center by replacing three long-chain alkyl groups (octadecyl) for three methyls reduces the selectivity coefficients of C0₃^2-, C₂O₄^2-, S₂O₃^2-, S0₄^2- and S0₃^-2-SE to major ions in the presence of Cl^- by the order of 3,3-3,8 at the same time reducing the detection limit of the electrodes by more than 2 orders. New ion-selective electrodes reversible to C0₃^2-, C₂O₄^2-, S₂O₃^2-, S0₄^2- and SO₃^2- have been proposed.

The associates of folic acid (FA) with silver nanoparticles (SNPs) have been formed in situ, using FA both as the reducing agent for Ag (I) and for functionalization of SNPs formed, and also by FA physical adsorption on the previously prepared SNPs. FA effectively reduces Ag(I) to Ag⁰. Ultrasound accelerates the SNPs' synthesis and promotes formation of monodis-perse particles. SNPs are not formed in medium containing FA and NH₃^.H₂0. FA and the products of its oxidation associated with SNPs lose the ability of fluorescence. Isopropyl alcohol is the most efficient solvent for precipitation of FA(SNP) associates from the synthesis medium. SNPs and FA(SNP) associates do not reduce viability of Ehrlich's ascites carcinoma cells and mesenchymal stromal cells.

The catalyst for NO reduction by carbon monoxide containing copper chromite, chromium, copper and iron oxides on y-Al₂O₃, has been developed. NO conversion over the catalyst in the reaction mixture containing 10 vol.% of oxygen is up to 83 % (200 °C, 12 000 h^-1). Carbon monoxide oxidation proceeds at the expense of catalyst lattice oxygen, and the resultant reduced sites are oxidized by nitrous oxide or oxygen from gaseous phase.

The kinetics of the peroxidase-catalyzed tetramethylbanzidine (TMB) oxidation has been studied in phosphate-citrate buffer (pH 6.0 and 6.4), containing 3-25 % of dimethylformamide (DMF), at 20 °C. The relationship between DMF concentration and kinetic parameters k_cat, K_M and k_cat/K_M has been determined. It has been shown that lg k_cat linearly decreased with increasing DMF concentration, whereas K_M value did not change. Kinetics of peroxidase-dependent TMB oxidation inhibition by two synthetic sulphur-containing α-tocopherol analogs at various DMF concentrations (3-25%) has been studed, and the inhibition constants K_i have been determined. It has been shown that with increasing DMF concentration, K_i values decreased from 15.8 to 3.2 μM. This fact is accounted for by DMF effect on the structures of peroxidase and inhibitors, as well as on their interaction, where the electrostatic interactions play a great part, since lgK_i is linearly dependent on (ε-1)/(2ε+1), where ε is the dielectric constant of the reaction medium.

Formation of patterned coatings suitable for Escherichia coli directed fixation on a solid surface, has been performed by the microcontact printing method in combination with Langmuir-Blodgett technology. The possibility has been shown for azithromycin introduction into Langmuir films based on a styrene-acrylic acid block copolymer. Adhesion of Escherichia coli cells to various types of surfaces has been investigated by atomic force microscopy. It has been shown that the antibiotic introduced into a polymer film, affects bacterial cells.

It was experimentally showed that high quality high-gloss films of amorphous type are formed at vacuum deposition of 1H-indole-3N-(phenyl)-aldonitrone. At laser exposure (λ = 351 nm) of films latent image of the mask is formed, which is manifested by vacuum radiation of quartz halogen lamp. The films with the thickness of 1,3±0,2 μm mask phosphorus and boron ions with the energy up to 1 000 eV (at implantation dozes 0,10-0,12 μK1/cm²) in silicon technology of obtaining of BIS.

Synthesis of new 10-oxa-13-aza- and 11-oxa-13-azaprostanoids of B series with aromatic moieties in the side chains has been accomplished from tetronic and 3-acetyltetronic acids. The immunopharmacological activities of prostanoids obtained have been estimated using the B-cellular immune response model. It has been found that, among the tested compounds, 11-oxa-13-azaprostanoids appear to be more promising immunostimulating agents as compared to 10-oxa-13-azaanalogues.

New preparation method of the methoxyfenozide, the most active insecticide compound of 1,2-diacyl-1-alkylhydrazine group, has been developed, using the improved procedures for synthesis of intermediate compounds.

By selective reduction of vanillin-related benzaldehydes, using NaBH₄ and Na [BH(OAc)₃], the corresponding alcohols and diols have been synthesized. Their esterification by acyl chlorides in the presence of Et₃N afforded functionally substituted esters and diesters containing fragments of heterocyclic compounds.

New derivatives of natural (2'-5')-oligoadenylates included double modifications in oligomer molecule have been synthesized. The synthesized compounds contain the ribavirin fragment or BAP-riboside as 5'-terminal or central nucleoside unit and 3'-deoxyadenosine (cordicepine) fragment at the 2'-end of oligomer chain. The modified (2'-5')-oligoadenylates have been obtained by the triester method. The compounds prepared may be of interest for investigation as antiviral agents in agriculture and medicine.

A new photosensitive polymer based on methylmethacrylate with methacrylamide and phenanthrenequinone has been obtained and investigated. The possibility for recording of holographic gratings in this material is shown. Chemical conditions for the formation of holograms has been discussed and confirmed by the spectral characteristics of the material.

A new method of obtaining new anion exchange fibers from «nitron», a polyacrylonitrile fiber, has been developed, and physicochemical properties of these fibers have been investigated. Water participation as a reagent in the reaction of amina-tion has been proved. Optimal molar ratio of reagents (DETA, water, С^Т (section of PAN)) and duration of the reaction have been established. It has been demonstrated that an anionite with exchange capacity 25-50 % greater than that of available fibers FIBAN А-5 can be prepared by this method.

The interphase polymerization technique and laboratory equipment for the modification of hollow fiber ultrafiltration membrane with «inside-out» filtration type has been developed and performed using polysulfone support PS-HF-100. It has been shown that this method allows obtaining membranes with reproducible characteristics. The effect of monomer concentration on membrane permeability and rejection has been studied.

The main thermodynamic properties of calcium carbonate crystals formed in the presence of organphosphorous compounds and carboxylic acids have been estimated. The inhibiting and dispersing properties of these substances and their impact on the morphology of the resulting carbonates' precipitate have been investigated. The mixtures of phosphonate, carboxylic and polycarboxylic acids inhibit the crystallization process at the stages of nucleation, crystal growth and particle aggregation of carbonates.

The exponential equation of diffusive kinetics for extraction of substances from vegetable raw materials with the correction parameter has been proposed. Algorithms for calculation have been considered and the comparative assessment of molecular diffusion coefficients for process of birch bark extraction by the traditional method and taking into account interpar-tial interactions in system, has been performed. With participation of components of vegetable raw materials, diffusive kinetic model adjusted for non-ideal interphase processes has been obtained.

Chemical interaction of abietic acid with diethylenetriamine at molar ratio of 1,0 : 1,2 and temperatures of 190 and 210 °С allows to obtain a product with acid number of 55 and 18 mg КОН/g, temperature of softening of 24-26 °С and 29-31 °С respectively, mixing unlimitedly with water and thermally stable up to 300 °С. This product can be used as a functional substance, capable of giving some water repellency to paper and cardboard and improving its strength.

Phosphogypsum accumulated in the dumps of JSC «Gomel Chemical Plant» in amount as much as 20 million tons could be one of the promising raw materials for cement production. The use of phosphogypsum in the cement industry as a mineral-izer for clinker burning process has been studied. It has been shown that the introduction of phosphogypsum in the feed mixture has a positive effect on the binding of calcium oxide during burning. The phase composition of clinkers and main properties of portland cement produced with the use of phosphogypsum, have been investigated.

Novel technology for regenerated cellulose fiber production from cellulose solutions in orthophosphoric acid has been developed. These solutions are found to be suitable for regenerated cellulose fiber spinning with the following physical and mechanical properties of fibers: strength, 22-30 cN/tex; elongation, 20-10%; elastic modulus, 600-1200 cN/tex. The fibres thus obtained are highly hydrophilic (hygroscopicity is about 10-18%). The samples of nonwoven fabric based on new regenerated cellulose fiber have been made by needlepunching technique. The technology has been scaled up to pilot plant machine with the capacity of 3000 kg per year.