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Complex comparative analysis of some modifiers based on refractory ceramic particles was carried out. Compositions based on nanodispersed tungsten and titanium carbides were obtained by a combined method (self-propagating high-temperature synthesis in combination with mechanochemical treatment). In experiments on intra-mould modification of grey cast iron and 110G13L steel, they demonstrated the maximum efficiency compared to other studied modifiers: within ceramic phase concentrations of 0.013-0.2 %, for gray cast iron, an increase in tensile strength was to 20 %, in hardness - to 13 %, in wear resistance - to 69 %, in corrosion resistance - 2.6 times; for steel, an increase in temporary tear resistance reached 18.0 %, in relative elongation - to 40 %, grain size reduction - by 6.8 times. As demonstrated during modification of grey cast iron by additives containing nanodispersed ceramic phases, not only the concentrations and composition of modifiers but also various process parameters (the design, the volume of the mold, the method of introduction of modifiers, etc. ) should be taken into account.

A colorimetric sensor based on a transparent polymethacrylate matrix modified with diphenylcarbazone was developed with a view to spectrophotometric determination of Hg(II) in various objects. The effect of pH of a solution of diphenylcarbazone on its immobilization into a polymer matrix was studied. The maximum value of the analytical signal was reached near 520 nm and remained almost unchanged in the 3-11 рН range, as established. During the study of complexation of diphenylcarbazone immobilized into a matrix with mercury(II) ions, there were found optimum conditions for determination of Hg²:^: рН 2.5-4 and duration of the interaction of mercury with diphenylcarbazone (with violet complex formation) of no more than 15 min. Mercury content was determined spectrophotometrically in the 1-25 µg/dm³ range by measuring absorption of light near 540 nm. The developed procedure of express analysis of mercury(II) was tested during studying organomercury granosan pesticide by indirect electrooxidation.

Decomposition and formation conditions of carbon dioxide hydrate were experimentally determined in porous matrix. As the latter, samples of γ, θ, and α phases of alumina with different porous structure, pore size distribution, and specific surface area were selected. The resulting deviation values of decomposition temperature from the equilibrium curve were compared with a possible diameter of hydrate species computed on the ground of the Gibbs-Thomson equations and known data about the porous structure of the used samples. Comparative analysis of the results of this work and earlier studies of hydrate formation processes in natural coals revealed qualitative differences.

The paper notes a crucial role of personal protective equipment (PPE) of skin integument during work with hazardous substances and liquidation of emergency at industry and transport enterprises. Earlier, two- and three-layer materials were used in the country and abroad to manufacture PPE of the isolating type. Currently, the leading companies manufacturing these means overseas for emergency PPE developed new four- and five-layer materials. These suits are present in the Russian market of PPE, however, their cost is quite high. For the first time in the country, the KazKhimNII JSC developed innovative multilayer LTL-1-2 material and its elastomer-based analogues. The universality of protective properties is due to selection of elastomers with different properties, specially developed formulations, and preparation method of composite materials. By protective properties, new isolating matters are not inferior to the best foreign materials of the highest level of protection. The developed innovative multilayer materials are designed to manufacture multifunctional isolating suits for personnel of industrial enterprises, objects of the Roscosmos State Corporation, and emergency response teams.

Research was carried out into the development of a lite protective flame-resistant rubberized material with a set of protective properties against aggressive media (acids and alkalis), gaseous highly toxic substances (chlorine and ammonia), solvents, and oils. The effect of the composition of rubbers on their protective properties was studied. Rubbers with improved protective properties were prepared on the basis of chlorosulphonated polyethylene combined with chloroprene rubber. A substantial impact of the nature of cross bonds and the type of vulcanizing agent on resistance of rubbers to aggressive media was determined. A series of antipyrenes with a total content of 60 pts. wt. were developed. They ensure preparation of self-extinguishing rubber upon preservation of residual durability. A protective lite material with the low surface density and good protecting properties compared to analogues was prepared on the ground of the data obtained.

Research into the development of siloxane rubbers with increased thermal and fire resistance was carried out. Rubber nanocomposites based on SKTB-1 siloxane rubber that were filled with aluminium trihydrate were obtained using domestic and foreign manufacture organobentonites. It was found that the introduction of organobentonites into siloxane rubbers filled with Al(OH)₃ contributed to an increase in their thermal and fire resistance. Fire-resistant and heat-protective materials, and also preparation technology of tissues by glue spreading using IBO 3320 and Siltex spreading machines were developed according to the results of experiments using glass, silica, and aramid fabrics as a reinforcing frame. Tests of the resulting materials were carried out and areas of application of protective clothing based thereon were proposed.

Properties of industrial copolymers were determined and the optimum ratios of monomers to obtain similar acrylic polymers were found. The effect of the composition of monomers on characteristic viscosity and relative hardness of acrylic copolymers based on methyl methacrylate and butyl methacrylate was studied. The optimum conditions for synthesis of acrylic copolymer with required properties were defined. Spray plastic with good performance properties was developed.

By the example of four types of soils of Udmurtia, sorption process by them of arsenic and chromium ions in extremely toxic forms is considered. Langmuir and Freundlich isotherms are constructed based on acquired experimental data and constants pointing to weak adsorption power of soils of the Non-Black Earth Zone in relation to these anions are determined. High solubility of arsenic and chromium species against weak sorption capacity of soils determines environmental risks of active migration of As(III) and Cr(VI) anions along soil profile. Their mobility should be taken into account during environmental monitoring.

A new approach towards determination of structure and composition of fragments coupled via a C--O bond in ethers and esters of petroleum and natural bitumen oils is developed. It is based on the use of the known chemical reaction of selective cleavage of ether/ester bridges in petroleum oil components using BBr₃. Unlike the known approach involving the stage for reduction of products of chemical modification of oils with lithium aluminium hydride, it is proposed to analyse the composition of the resulting organic bromides by the GC-MS method. Mono- and dibromo derivatives of C₁₃-C₂₂ alkyltrimethylbenzenes are identified in chemical modification products on an example of natural bitumen oils from the Ashalchinsk field (Tatarstan). Unlike С₁₈-С₂₂ compounds, С₁₃-С₁₇ homologues are not detected in initial oils, therefore they are entirely coupled to other fragments of complex high molecular mass formations by one or two ester-ether bridges. Furthermore, as established during analysis of GC/MS results, there are ions corresponding to monobromides of characteristic fragment ions of n -alkanes, and also to mono- and dibromides of characteristic molecular ions of naphthalene, phenanthrene, dibenzothiophene, and their homologues. Hence, in complex high molecular mass formations of the studied oils, some of the listed compounds are linked via one or two ether/ester bridges.

The recycling process of carbon fibres was investigated using thermal solvolysis of polymer composites in the medium of coal tar pitch in the 320–400 °С temperature range. The effect of thermal treatment therein on properties of carbon fibres isolated via the recycling was investigated. The paper presents research data by scanning electron microscopy and mechanical tests of isolated carbon fibres compared to the initial ones used for composite synthesis.