CRUST | Browsing by Author "Sukhyy, Kostyantyn M."

Browsing by Author "Sukhyy, Kostyantyn M."

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Bifurcation State and Rational Design of Three-Layer Reinforced Compound Cone-Cylinder Shell Structure under Combined Loading
(Publishing House “Akademperiodyka”, Kyiv, 2023) Gristchak, V. Z.; Hryshchak, D. V.; Dyachenko, N. M.; Sanin, A. F.; Sukhyy, Kostyantyn M.
ENG: An analytical-numerical approach to solving the problem of state bifurcation in terms of local and overall stability of a three-layer cone-cylinder shell structure discretely supported by intermediate rings, in particular of modern launch vehicles, under static combined loading by external pressure, axial forces, and torque is proposed in the paper taking into account the stiffness parameters of the intermediate rings in the plane of the initial curvature and for torsion. Corresponding solving equations for the problem are ordinary differential equations of the sixth order (for a cylindrical compartment with constant coefficients and for a conical one with variable coefficients along the axial coordinate). Differential relations that determine the conditions of conjugation through the intermediate ring are used. For the numerical solution, the finite difference method is used with central finite differences of the third and second order at the inner points of the shell determination segments and at its ends, respectively, and the second order differences with one step backward or forward at the conjugation points through the ring. The agreement of the calculation results with the known data for three-layer conical and cylindrical shells is shown, as well as in the limiting case, it is done when passing to a single-layer compound cone-cylinder structure. For the considered class of cone-cylinder shell structures, boundary surfaces are constructed that separate the stability region of the structure being under study, depending on the geometric and stiffness parameters of the compartments, reinforcing elements, and the external load condition. The external load effect on the parameter of the post-critical wave formation for the structure under investigation is studied, providing the visualization of the deformation behavior. The analysis of the calculation results has shown that this approach to solving the problem of bifurcation and equistability of the compound structure compartments in relation to the local and overall forms of protrusion allows choosing rational geometric and stiffness parameters of the shell components and force elements in terms of improving the weight characteristics of the structure.
Carbon Materials for Electrically Conductive Concrete
(EDP Sciences - Web of Conferences, France, 2024) Savytskyi, Mykola V.; Sukhyy, Kostyantyn M.; Savytskyi, Oleksandr M.; Babenko, Maryna; Shevchenko, Tetyana
ENG: In recent decades, the direction of building materials science related to the creation of Smart Concretes has been rapidly developing. Smart Concretes, in addition to the functions of a structural material, also perform other functions that are related to their new properties. Among the large number of Smart Concretes, it is necessary to highlight Electrically Conductive Smart Concrete. This type of concrete is obtained by adding conductive fillers to the concrete mixture. Among them, carbon materials are the most promising in terms of their properties. Despite the large number of conducted studies of conductive fillers and conductive concrete, there is still no generalization and systematization of them. In addition, there are no standards for testing the conductive properties of both fillers and concretes. Therefore, the authors aimed to systematize data on Electrically Conductive Smart Concrete, as well as electrically conductive carbon fillers. A method for testing the electrical conductivity of Carbon Nanomaterials (CNMs) as fillers for Electrically Conductive Concrete is proposed. Approbation of the proposed method was carried out by determining the electrotechnical indicators of carbon fillers, such as coke breeze and carbon black.
Development of Rare Earth Metal-Modified Heat-Resistant Coatings for Gas Turbine Blades
(Ukrainian State University of Chemical Technology, Dnipro, 2024) Yefanov, V. S.; Gnatenko, M. O.; Laptieva, H. M.; Basov, Y. F.; Sukhyy, Kostyantyn M.; Kovalyov, S. V.; Popov, S. M.
ENG: This paper presents an investigation into the influence of Y-La and Y-Hf-La modifiers on the structure and properties of Ni-Cr-Al consumable cathodes used for heat-resistant coatings on turbine blades via the arc-ion plating method. The study shows that the introduction of these modifiers positively affects the structure formation process of the consumable cathodes. The modifiers contribute to a higher degree of microstructural homogeneity in the cathodes, achieved through the formation of nanosized stabilizing phases between the alloying elements and the rare earth metal groups. This study experimentally confirms that Ni-Cr-Al coatings produced with the Y-La and Y-Hf-La modified cathodes outperform traditional Y-only modified coatings in oxidation tests. Structural analysis of the coatings reveals that samples with Y-Hf-La exhibit greater homogeneity and fewer defects, which is particularly important when depositing coatings with large thicknesses (over 40 µm). It was found that the introduction of the Y-Hf-La complex enables the application of coatings up to 90 µm thick by forming a less defective structure. Additionally, it has been established that Y-Hf-La modification enhances the adhesion of the coating to the substrate and allows for maximum uniformity in the distribution of alloying elements throughout the entire thickness of the applied coating.
A Facile Two-Step PVP-Assisted Deposition of Co-Activated Nanosized Nickel Hydroxide Directly on a Substrate for Large-Scale Production of Supercapacitor Electrodes
(MDPI, 2023) Kotok, Valerii; Ondrejka, Peter; Mikolášek, Miroslav; Sojková, Michaela; Novák, Patrik; Gregor, Maroš; Kovalenko, Vadym; Sukhyy, Kostyantyn M.
ENG: The self-decomposition reaction of the nickel ammonia complex was used for the nickel hydroxide formation on the nickel foam with further modification in several ways. The addition of polyvinyl pyrrolidone (PVP) and the electrochemical or chemical activation with cobalt hydroxide was used to modify the formation method. In all cases, structures with Ni(OH)2 nanoflakes were formed. It was found that the flower-like particles of Co(OH)2 were precipitated during chemical activation among the nanoflakes. It was shown that the presence of PVP during the nickel ammonia complex decomposition suppressed the highly branched particles. The absence of the highly branched particles increased the capacitive properties of the formed electrode at high current densities. The highest capacitance in 1408 F/g at 1 A/g was shown for the sample precipitated with the PVP presence and the further chemical activation by cobalt.
The Influence of Solid-State Polycondensation of Polyethylene Terephthalate on Its Rheological Properties
(Ukrainian State University of Chemical Technology, Dnipro, 2024) Chervakov, Denys O.; Ved, V. V.; Fedan, V. V.; Sukhyy, Kostyantyn M.; Chervakov, Oleh V.
ENG: The influence of solid-state polycondensation conditions on the rheological properties of polyethylene terephthalate was determined. Mathematical models describing the dependence of the melt flow rate of both virgin and recycled polyethylene terephthalate on the time and temperature of the solid-state polycondensation process were developed. A correlation between the melt flow rate and the average molecular weight of polyethylene terephthalate was demonstrated. Experimental studies showed that conducting solid-state polycondensation of recycled polyethylene terephthalate at temperatures ranging from 130 оC to 160 оC for 3 hours produces polymeric materials with higher molecular weight and, consequently, improved performance properties.
Innovative Technological Concept for the Production of High-Density Cathodes for Lithium Reserve Power Sources with Increased Specific Energy
(Ukrainian State University of Chemical Technology, Dnipro, 2024) Markevych, O. V.; Polishchuk, Y. V.; Zinin, V. V.; Vavilon, K. I.; Sukhyy, Kostyantyn M.
ENG: This paper presents an innovative technological concept that significantly enhances the specific energy (both gravimetric and volumetric) of primary lithium power sources. A composition and laboratory-scale process for manufacturing composite cathodes with minimal electrochemically inactive («ballast») components have been developed. The proposed approach enables the production of high-density cathodes without significantly reducing their porosity. The composite cathodes were tested in disc-shaped primary power sources with dimensions of 2325 (23 mm in diameter and 2.5 mm in height). The effect of graphene content in the cathode mass on the discharge voltage of the cells was investigated. It was demonstrated that a graphene content of 3 % by weight of MnO2 in the cathode mass increases the average discharge voltage of the cells from 2.1 V to 2.5 V at a discharge current of 1 mA. Testing at a discharge current of 1 mA revealed that the capacity of the developed cells exceeds that of the best commercial counterparts by at least 40 %.
Oleochemical Products in Synthesis Technologies of Eco-Friendly Polymers
(Oles Honchar Dnipro National University, Dnipro, 2024) Chervakov, Oleh V.; Chervakov, Denys O.; Sukhyy, Kostyantyn M.; Kuzminskyi, Vitalii Yu.; Varlan, Kostiantyn Ye.; Belyanovskaya, Elena A.; Levchenko, Yevhenii P.; Yurchik, Mykhailo S.
ENG: Promising directions of synthesis from renewable vegetable oil raw materials of monomeric and oligomeric oleochemical products are considered: modified triglycerides as ingredients of special-purpose polymer compositions; fatty alcohols, esters and amides of fatty acids as surfactants in detergents, cosmetics, paints, pharmaceuticals, as ecological fuel; polyols and hydroxyl-containing oligomers for the synthesis of polyurethane, polyesteramide, polyurethaneamide binders and coatings with anti-corrosion and antimicrobial properties. The synthesis routes of fatty acid amides, in particular hydroxyl-containing ones with a functionality of 2 or more, as starting compounds for promising polyesteramides are considered in detail. The strategy of synthesis from vegetable oils of saturated polyols with primary hydroxyl groups as promising components for environmentally friendly paint and varnish compositions is considered. Data on the synthesis and properties of polyurethaneamides, polyesteramides and metal-containing derivatives based on them are presented. For each product type an analysis was made of the state of development of a particular technology, as well as future prospects and existing barriers to their development. The possibility of using metal-containing polymers to create biodegradable materials and coatings with hydrophobic properties and antimicrobial activity was shown.
Peculiarities of High-Temperature Refining of Carbon Materials
(Ukrainian State University of Chemical Technology, Dnipro, 2023) Sybir, A. V.; Hubynskyi, Semen M.; Fedorov, Serhii S.; Sukhyy, Kostyantyn M.; Hubynskyi, M. V.; Vvedenska, T. Y.
ENG: The purpose of the study was to determine the influence of the main following factors on the efficiency of the process of high-temperature refining of natural and artificial graphite: processing temperature, distribution of metal oxides, and changes in the aggregate state of ash impurities. Thermal processing of natural graphite from Ukrainian deposits and anthracite from Donetsk coal basin was carried out in a chamber furnace at a holding time of 10–20 minutes in a temperature range of 1500–30000 Ñ. The quality of refining was carried out by ICP-OES and XRF analysis methods. It was established that the refining process may be divided into three following periods: 0–16000 Ñ (removal of moisture, volatiles, and decomposition of carbonates); 1600–26000 Ñ (evaporation of main ash-forming metals Fe, Si, Al, Ca, Mg in the form of oxides, silicides, and carbides); and 2600–30000 Ñ (evaporation of refractory compounds Ti, V, Mo, the content of which in the initial raw material determines the processing temperature and the quality of the final product). The distribution of metal oxides in the initial carbon material is not uniform, which complicates the use of equilibrium state models. The transition of ash into the liquid and then gaseous state has a significant impact on the result of heat treatment. This is what determines the choice of the process scheme. Intermittent process is the heating by an external heater in an inert gas environment. Continuous process is the heating of the material in moving containers or processing in an electrothermal fluidized bed.
Performance of Heat Pump Based on Composite Adsorbent ‘Silica Gel – Crystalline Hydrate’
(Odesa National University of Technology, Odesa, 2025) Belyanovskaya, Elena A.; Sukhyy, Kostyantyn M.; Serhiienko, Yana O.; Sukhyy, Mikhaylo K.; Sukha, Irina V.
ENG: Performance of an adsorptive heat pump has been studied. The factors affecting the efficiency of its work have been analyzed. Operating parameters and efficiency of adsorptive heat pumps and adsorptive heat storage devices have been compared. An algorithm of calculating the basic operating characteristics of an adsorption heat pump in heat supply systems has been proposed. It involves calculating the mass transfer coefficient, final absolute humidity of the air flow passed though adsorbent layer, the water uptake or adsorption and the useful heat of adsorption and heat of condensation, determination of heat inputs for the operation of the device such as heating the adsorbent, case of the device, hydraulic circuit, the water in the tank and adsorbed water, heat of desorption and heat of evaporation, estimation the coefficient of energy performance. The evaluation criteria of the efficiency of adsorptive heat pumps and heat storage devices have been compared. It is shown that the operating parameters of the adsorptive heat pump and the adsorptive thermal energy storage device based on composite adsorbents ‘silica gel – sodium sulfate’ and ‘silica gel – sodium acetate’ are the same, i.e. airflow rate 0.08 - 0.1 m3/s and initial absolute humidity of airflow 0.03 – 0.04 kg/m3, which are corresponded with maximal efficiency of the device. The temperature of the humid air flow directed to the adsorbent layer is suggested to be set at 20 – 40 °C. The measures to increase the efficiency of the adsorptive heat pump are proposed. It is shown that ultrasonic air humidification allows to increase the coefficient of energy performance by almost 2 times compared to steam humidification. The obtained results can be used for developing energy-efficient heating systems of residential premises.
Production of Fiberglass Plastics Using Infrared Heating
(Український державний хіміко-технологічний університет, Дніпро, 2025) Manko, T.; Husarova, I.; Kozis, K.; Sukha, Iryna V.; Zaichuk, Oleksandr V.; Sukhyy, Kostyantyn M.
ENG: This study analyzes the technology for creating polymer composite materials reinforced with glass fiber. Particular attention is given to their applications in the aerospace industry, where stringent requirements for strength, corrosion resistance, and specific strength render these materials indispensable. The main components of composite materials and their properties are examined. Phenol-formaldehyde resins, widely utilized as a matrix for fiberglass plastics in rocket and space engineering, are studied in detail. The thermomechanical resistance of composites, a critical factor determining their performance under extreme conditions, is highlighted. A significant part of the study focuses on the production and curing processes of composite materials. Various curing methods are analyzed, with a focus on the effectiveness of infrared radiation. The findings establish that infrared heating significantly enhances the physical and mechanical properties of composites while reducing production time.
Properties of Zr–Ti–Nb and Ti–Al–V Alloys
(Ukrainian State University of Chemical Technology, Dnipro, 2024) Kovalyov, S. V.; Ovchynnykov, O. V.; Sukhyy, Kostyantyn M.; Yefanov, V. S.; Kalinichenko, O. O.; Koval’ova, N. V.
ENG: This article is devoted to studying the properties of the new Zr–Ti–Nb alloy and comparing it with the well-known Ti–Al–V alloy (ÂÒ-6, Grade 5 analog). The properties were analyzed through chemical composition determination and corrosion resistance assessment. The Zr–Ti–Nb alloy does not contain the toxic impurities present in the Ti–Al–V alloy, specifically aluminum and vanadium. Structural studies were conducted to identify the phases (X-ray diffraction analysis) and their composition using scanning electron microscopy. The microstructure and phase composition of the Zr–Ti–Nb alloy indicated a uniform distribution of elements throughout the alloy. The wetting angle of the Zr–Ti–Nb alloy with an oxide layer is significantly smaller than that of the Ti–Al–V alloy, suggesting greater hydrophilicity. Physical research methods included determining density, reflectivity, and electrical conductivity. Mechanical properties were examined by determining the elastic modulus, strength limit, yield strength, longitudinal elongation, transverse contraction, and microhardness. Notably, the elastic modulus of the Zr–Ti–Nb alloy is 26.4 GPa, similar to that of cortical bone, in contrast to the Ti–Al–V alloy, which has an elastic modulus of 110–140 GPa. The obtained data indicate that the superior chemical and mechanical properties of the Zr–Ti–Nb alloy make it suitable for medical applications.
Rheological Properties of Polymer-Polymer Mixtures on Corn Starch Base
(MM Publishing s.r.o., Praha, Czechia, 2022) Rimar, Miroslav; Tretyakoff, Artem; Sukhyy, Kostyantyn M.; Yeromin, Oleksandr O.; Kulikov, Andrii; Fedak, Marcel; Belyanovskaya, Elena; Shunkin, Ihnat; Gupalo, Olena V.; Krenicky, Tibor
ENG: The prospects for the use of polymer-polymer mixtures based on corn starch as alternative thermoplastic materials to polyolefins are considered. Rheological curves have been obtained, which confirm the possibility of processing such mixtures on standard equipment into products. It is shown that the starch content in polymer-polymer mixtures can reach 90 mass percent. Compared to existing biodegradable polymers, plasticized starch-based material is in no way inferior to them in terms of processability. Studies of the mechanical properties of polymer-polymer mixtures based on corn starch have been carried out. The data obtained indicate the possibility of using the developed composites as packaging materials, as well as alternative materials to known bioplastics and synthetic polymers.
Selection Criteria of Working Pairs Adsorbent – Adsorbate for Thermal Energy Transformers
(MM Science Journal, Czech Republic, 2022) Rimar, Miroslav; Sukhyy, Kostyantyn M.; Belyanovskaya, Elena; Yeromin, Oleksandr O.; Prokopenko, Elena M.; Kulikov, Andrii; Fedak, Marcel; Frolova, Lilia; Pustovoy, Grigoriy; Kulikova, Olha; Savko, Vitalii
ENG: In the manuscript the main factors that affect the thermal mass of open and closed types of heat storage devices are shown. Also, the main requirements for adsorption modules are given. The calculation procedure has been refined, which includes the determination of heat load, heat of adsorption, adsorbent mass, as well as integral, structural, and specific thermal mass. The specific thermal masses of adsorption heat-accumulating modules of open and closed types were evaluated. The main factors affecting their value are analysed. It is shown that the specific thermal mass of the adsorption heat storage module increases significantly due to the adsorption of water during the discharge of the device. It is shown that it reaches its maximum values at the end of the discharge stage, when the maximum values of adsorption in the cycle are reached. The influence of the design of the heat storage module on the value of the specific thermal mass has been confirmed. It is shown that the maximum values of these changes correspond to the composites containing 80% salt and 20% silica gel, due to the maximum values of the limiting adsorption and the heat of adsorption, which contributes to the lower values of the adsorbent mass, which is required to cover the thermal load. Specific thermal masses of adsorption modules based on "silica gel – sodium sulphate" and "silica gel - sodium acetate" composites are compared. The composition of the composite is 80% sodium sulphate and 20% silica gel, which corresponds to the minimum dimensions of the adsorption module, and therefore the maximum value of the specific thermal mass.
Solid-Phase Polycondensation of Polyethylene Terephthalate with Technologies of Its Reactive Extrusion
(MM Publishing s.r.o., Praha, Czechia, 2023) Rimar, Miroslav; Chervakov, Denys O.; Fedak, Marcel; Kulikov, Andrii; Kulikova, Olha; Sukhyy, Kostyantyn M.; Chervakov, Oleh V.; Bentsionov, Igor; Sverdlikovska, Olga S.; Belyanovskaya, Elena; Yeromin, Oleksandr O.; Prokopenko, Olena M.
ENG: It has been experimentally confirmed that polyethylene terephthalate during its processing into products destruct without carrying out the process of solid-phase polycondensation. The conditions for both primary and secondary polyethylene terephthalate have been determined for carrying out the process of solid-phase polycondensation for its effective reaction extrusion with chain extenders. To confirm the effectiveness of the parameters of the solid-phase polycondensation process of polyethylene terephthalate, its reaction extrusion was carried out with commercially available chain extenders of the diepoxide class. The optimal content of chain extenders of the diepoxide class for changing the complex of physical, mechanical and rheological properties of polyethylene terephthalate modified by them was determined. It allows obtaining materials with an increased by 2.2 times characteristic viscosity.
Thermodynamic Analysis of the Reactions of Strontium Anorthite Formation during the Firing of Thermal Shock Resistance Ceramics Based on the Eutectic Glasses of the SrO–Al2O3–SiO2 Systems
(Ukrainian State University of Chemical Technology, Dnipro, 2023) Zaichuk, Oleksandr V.; Sukhyy, Kostyantyn M.; Amelina, O. A.; Hordeieiv, Y. S.; Filonenko, D. V.; Rudnieva, L. L.; Sukha, Iryna V. ; Halushka, S. A.
ENG: Thermal shock resistance ceramic materials must have a high degree of sintering to ensure the required mechanical strength, erosion resistance, and resistance to high-temperature oxidation. However, the search for effective ways to achieve a high degree of sintering of ceramic materials based on the SrO–Al2O3–SiO2 system at low temperatures requires a large amount of experimental research. The aim of this work is to analyze thermodynamically the reactions of strontium-anorthite phase formation at the points of triple eutectics of the SrO–Al2O3–SiO2 system under low-temperature firing conditions. The eutectic points were selected in the region of strontium anorthite crystallization and had a temperature not exceeding 14000C. It has been established that in the case of compliance with the stoichiometric ratio, the final product of the interaction of the components of eutectic glasses S-1 and S-2 with the charging components is the strontium anorthite phase. The most probable is the formation of strontium anorthite in the interaction of eutectic glass components with Al2O3∙2SiO2, which is a product of kaolinite dehydration (Al2O3∙2SiO2∙2H2O). It has been found that the compounds SrO∙SiO2 and 2SrO∙Al2O3∙SiO2 are most active in the interaction with the charging components in the direction of formation of the strontium anorthite phase than SiO2 tridymite. As a result, the sintering of strontium-anorthite compositions at a temperature of 9000C causes a significant increase in the content of the crystalline phase of strontium anorthite. The determined patterns allow making a reasonable choice of glass in the SrO–Al2O3–SiO2 system for the further manufacture of low-temperature strontium-anorthite ceramics.

Browsing by Author "Sukhyy, Kostyantyn M."

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