A series of samples of zeolite-containing microspheres (ZCMS) and fluid catalytic cracking (FCC) catalysts based on Prosyana (Ukraine) kaolin were synthesized in situ. Their adsorption and chemisorption characteristics were recorded using a nitrogen low-temperature adsorption/desorption method and temperature programmed desorption (TPD) of ammonia, respectively. It was shown that changes in the synthesis conditions had a considerable impact on the microand meso-porosity of the samples. A low-temperature band dominated the ammonia TPD spectra of the ZCMS samples, reflecting the retention of ammonia by the sodium cations of the zeolite acting as weak Lewis acid sites. ZCMS was found to display an appreciable activity in cumene cracking at 723 K.It was shown that during the conversion of ZCMS to FCC catalysts through the decationization and ultra-stabilization of the zeolite phase, the latter is appreciably destroyed giving rise to a considerable increase in the mesoporosity of the samples without any change in the average diameters of such mesopores.It was concluded that the catalyst stability is characterized by pores of an intermediate (20-30 Å) diameter, thereby demonstrating the strength of the linkage between the zeolite and matrix phases.The zeolite phase content and adsorption characteristics of catalysts prepared on the basis of Prosyana kaolin meet the demands of modern FCC catalysts.

An issue related to using cable products for building structures is to ensure their stability and durability when operating within wide limits. Therefore, the object of research was a change in the properties of the polymer sheath of the cable during the formation of a swollen coating layer under the influence of high temperature. It is proved that in the process of thermal action on the flame retardant coating, the process of thermal insulation of the cable involves the formation of particulate products on the surface of the sample. Under the action of the burner flame, a temperature was reached on the surface of the sample, which led to a swelling of the coating of more than 16 mm. The measured temperature on the inverse surface of the sample was no more than 160 °C, which indicates the formation of a barrier for temperature. In this regard, a calculation and experimental method for determining thermal conductivity when using a flame retardant as a coating has been developed, which makes it possible to estimate the coefficients of temperature conductivity and thermal conductivity under high-temperature action. According to the experimental data and established dependences, the coefficients of temperature conductivity and thermal conductivity of wood were calculated, which are 214.4·10–6 m2/s and 0.62 W/(m∙K), respectively, due to the formation of a heat-insulating swollen layer. The maximum possible temperature penetration through the thickness of the coating was assessed. A temperature was created on the surface of the sample, which significantly exceeds the ignition temperature of the polymer sheath of the cable, and, on a non-heated surface, does not exceed 160 °C. Thus, there is reason to argue about the possibility of directed adjustment of the fire protection processes of an electrical cable by using coatings capable of forming a protective layer on the surface of the material, which inhibits the rate of heat transfer.

The issue related to using dry wood products for building structures is to ensure their stability and durability during operation while it is necessary to take into consideration changes in their properties and structure. Therefore, the object of this study was pine wood struck by drying out. It is proved that in the process of drying, wood porosity decreases, and, accordingly, the tensile strength, depending on the degree of damage by the fungus. Specifically, with the area of damage in the range of 30‒50 %, the strength limit decreases by more than 1.3 times, and if the fungus affects the area within 80÷100 %, the wood becomes softer, more ductile while the strength limit is reduced by 1.1 times. Based on the results of physicochemical studies, discrepancies in the IR spectra were identified, indicating structural changes in the constituent components of wood. There is a decrease or absence of intensities of absorption bands of some functional groups and the appearance or intensification of others. Wood samples, in determining the highest calorific value, show a difference in values, which is explained by structural changes in wood components caused by biological processes. Thermogravimetric analysis data indicate complete burnout of dry pine wood. However, for wood with tree stands not weakened by drying, the coke residue burns out at a higher temperature. Wood with blue pigmentation affected by microorganisms has significant differences in the heating area of 400÷700 °C. The nature of coke burnout allows us to make assumptions about the different qualitative and quantitative composition of the coke residue, which is formed due to structural changes. The practical significance is the fact that the results of determining the properties and structure of dry wood make it possible to establish the operating conditions for articles and building structures

An issue related to using wood and wood products for building structures is to ensure their stability and durability during operation within wide limits. Therefore, the object of this study was a change in the properties of the polymer shell of powder paint on wood during thermal modification. It is proved that in the process of thermal modification of wood, its structure changes, and accordingly, during the polymerization of powder paint, degassing occurs, which affects the polymer shell. Namely, during the thermal polymerization of powder paint at a temperature of 180 °C for untreated wood, shallow bubbles and craters are characteristic of the formed polymer shell. Instead, a smooth surface is marked for a sample of thermally modified wood. Thermogravimetric analysis data show thermogravimetric curves characterized by the loss of mass of the sample of the original wood with increasing temperature due to the processes of dehydration, destruction of hemicellulose and lignin. This is dehydration, accompanied by the destruction of the pyranose cycle, and carbonization to form a carbon residue and a complex mixture of volatile products. Due to this, bubbles and craters are formed in the polymer shell of the coating. Based on the obtained results of adhesion of the polymer shell on wood, which is treated with a mixture of epoxy polyester system with functional additives and a polymerization temperature of 180 °C, the adhesion level is 2.1 MPa. Reducing the polymerization temperature of a mixture of the epoxy polyester system with functional additives to 130 °C increases adhesion by 1.75 times, and the nature of the destruction passes through the polymer shell. For thermally modified wood, the level of adhesion is within 2.1 MPa, and the destruction takes place through the wood. This is due to the increased fragility of the surface after thermal modification of wood

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