Видання зареєстровані авторами шляхом самоархівування
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Item The usage of material quality indicators to assess the properties of linear block-copolyurethanes based on oligoeters(MM Publishing, 2022) Panda, A.; Anisimov, V.M.; Anisimov, V.V.; Дядюра, Костянтин Олександрович; Diadiura, Kostiantyn Oleksandrovych; Pandova, I.The relationship of the structure with the strength, deformation, thermophysical and tribological characteristics of linear block-copolyurethanes based on oligoeters of regular structure oligooxy tetra-methylene glycol is described by mathematical model. Quality parameters are used to estimate the relationship between the structure and properties of the studied materials. The quality parameters allowed to find optimal composition of initial components.Item Model for assessing the safety index of constructions based on hydroxyapatite(MM Science Journall, 2022) Chernobrovchenko, V.; Panda, A.; Dyadyura, K.; Висоцький, Ігор Юрійович; Vysotskyi, Ihor Yuriiovych; Pandova, I.Synthetic hydroxyapatite is used in biomedical engineering for its desirable mechanical properties. But not all scaffolds are biocompatible in use. The safety of implants depends on the competence of medical personnel, manufacturing technology, as well as biological, mechanical and other properties. Although there are regulatory standards for the safety of biomaterials, the assessment of their biocompatibility is a difficult task, which is associated with the properties of spacesuits, the duration of contact with tissues. The article proposes a method for assessing the safety of implants depending on various factors that form their biocompatibility.Item Rotors of Vertical-Axial Wind Turbines Assembled in Bearings and Aerodynamic Characteristics of a Blade with Unclosed Wing Profile(Sciendo, 2022) Panda, A.; Rozhkova, L.; Кузнєцов, Едуард Геннадійович; Kuznietsov, Eduard Hennadiiovych; Нагорний, Володимир В`ячеславович; Nahornyi, Volodymyr ViacheslavovychIn world practice, traditional blades used in high-speed wind turbines, both horizontal-axial and vertical-axial, have a wing-shaped profile. However, for horizontal-axial wind turbines, blades with such a profile have a fairly narrow range of operating values of the angle of attack of the incoming air flow and a low value of the moment of pulling from place. As for vertical-axial wind turbines, the self-starting of the rotor with wing blades is completely absent and additional devices are needed to start the rotor into operation. In order to ensure the self-starting of the rotor and the operation of the wind turbine at high and low wind speeds, a new shape of the blade profile was developed, called non-closed wing profile. The concept of the development is that the blade should have a configuration in which the pulling force is involved at the beginning of the movement, and then, with the establishing of the movement, a lifting force would arise, which acquires a prevailing character in the operating mode. The article presents the results of experimental studies of the aerodynamic characteristics of the developed non-closed wing blades. One of the results obtained is to determine the effect of the thickness of the blade profile on the range of values of subcritical angles of attack of the incoming air flow and the differences between the nature and range of changes in the coefficients of lifting force and pulling force in a traditional wing blade and a blade with a non-closed wing profile. Studies of the rotor model of a vertical-axial wind turbine with non-closed wing blades have confirmed the presence of its self-starting and operability even at low wind speeds.Item Ecotoxicity Study of New Composite Materials Based on Epoxy Matrix DER-331 Filled with Biocides Used for Industrial Applications(MDPI, 2022) Panda, A.; Dyadyura, K.; Valíček, J.; Harničárová, M.; Kušnerová, M.; Івахнюк, Тетяна Василівна; Ивахнюк, Татьяна Васильевна; Ivakhniuk, Tetiana Vasylivna; Гребеник, Людмила Іванівна; Гребеник, Людмила Ивановна; Hrebenyk, Liudmyla Ivanivna; Sapronov, O.; Sotsenko, V.; Vorobiov, P.; Levytskyi, V.; Buketov, A.; Pandová, I.The impact of fillers in the epoxy oligomer on the test culture of the marine ecosystem was investigated. The content of additive—biocides—was selected based on the complex research using STAT-GRAPHICS® Centurion XVI. The ecotoxicity of composite surfaces was determined in model systems using methods which are standard in eco-microbiology. The microorganism was identified by studying morphological, cultural, biochemical, and antigenic properties. Studies of the structure and the microrelief of the surfaces of composite materials were conducted using scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy. Based on comprehensive research, it was established that the composition of oxytetracycline with content of q = 1.5 wt% and nanosilver with a content of q = 0.075 wt% per 100 wt% of the DER-331 oligomer and 10 parts by the mass of the TETA hardener ensures the formation of a porous nano-heterogeneous structure of the coating, which leads to the acceleration of the release of silver ions from the surface of the polymer. The rational content of the complex additives of biocides ensures adhesion to the cell wall of bacteria with subsequent penetration into it and subsequent change to the cell membrane, its death, and, therefore, the suppression of the fouling process of metal structures.Item Method of Using the Correlation between the Surface Roughness of Metallic Materials and the Sound Generated during the Controlled Machining Process(MDPI, 2022) Нагорний, Володимир В`ячеславович; Нагорный, Владимир Вячеславович; Nahornyi, Volodymyr Viacheslavovych; Panda, A.; Valicek, J.; Harnicarova, M.; Kusnerova, M.; Pandova, I.; Legutko, S.; Palkova, Z.; Lukac, O.The article aims to use the generated sound as operational information needed for adaptive control of the metalworking process and early monitoring and diagnosis of the condition of the machined materials using a newly introduced surface roughness quality index due to the sound-controlled machining process. The object of the measurement was correlation between the sound intensity generated during cutting and the material parameters of the machined surface, i.e., the roughness of the machined surface and the degree of wear of the cutting tool. The roughness was measured during longitudinal turning of a steel billet with a P25 insert made of 12X18H10T steel and a T15K6 cutting insert made of a titanium, cobalt, and tungsten group alloy. The correlation between the sound and roughness of the machined surface was 0.93, whereas between the sound and wear of the cutting tool was 0.93. The correlation between sound and tool wear in the experiment with P25 and T15K6 cutting inserts and the correlation between sound and roughness is positive.Item Wear Resistance Improvement of Linear Block-Polyurethanes Under Conditions of Liquid Friction(Sciendo, 2021) Panda, A.; Anisimov, V.M.; Anisimov, V.V.; Дядюра, Костянтин Олександрович; Дядюра, Константин Александрович; Diadiura, Kostiantyn OleksandrovychA significant disadvantage of parts made of linear block polyurethanes under conditions of friction contact in the presence of an aqueous medium is the intensification of hydrolysis processes and decrease in volume strength. It was proposed to slow down the hydrolysis of polyurethanes in three ways: by directed changes in chemical struc-ture, by electromagnetic radiation of different intensities and by creation of composite materials, based on the principle of additional intermolecular crosslinking at the manufacturing and hot processing stages. The conditions for the formation of a smooth wear-resistant surface that protects the material from rapid destruction are re-vealed.Item Increasing of wear resistance of linear block-polyurethanes by thermal processing methods(MM Science Journal, Czech Republic, 2021) Panda, A.; Anisimov, V.M.; Anisimov, V.V.; Дядюра, Костянтин Олександрович; Дядюра, Константин Александрович; Diadiura, Kostiantyn Oleksandrovych; Pandova, I.A significant imperfection of parts made from linear block polyurethanes under conditions of friction contact in the presence of water medium is an intensification of hydrolysis processes and reduction of bulk strength. In order to slow down the hydrolysis process, samples of the polyurethanes were subjected to three types of thermal impacts: thermal processing during some time, infrared and laser irradiation. It has been established that processing in thermal fields of different intensity allows 5-10 times increase of wear resistance of these materials during friction in water medium.Item Vibration forecasting by the results of synchronous control of water level changes in several observing wells(MM Science Journal, Czech Republic, 2021) Panda, A.; Нагорний, Володимир В`ячеславович; Нагорный, Владимир Вячеславович; Nahornyi, Volodymyr Viacheslavovych; Pigulevsky, P.; Pandova, I.The article presents the results of approbation of the vibration forecasting methodology based on the synchronous measurement results of water level fluctuations in several observing wells. These fluctuations are caused by the shocks impact generated in a distant source of a maturing vibration. The approbation demonstrated the reliable forecast possibility of earthquake time and its epicenter coordinates.Item Forecasting an vibration by monitoring the dynamics of changes its precursors of various physical nature(MM Science Journal, Czech Republic, 2021) Нагорний, Володимир В`ячеславович; Нагорный, Владимир Вячеславович; Nahornyi, Volodymyr Viacheslavovych; Panda, A.; Straser, V.; Pandova, I.Prediction crosses all fields of Science, being itself the evident manifestation of the Scientific Method. This study addresses the delicate aspect of vibration forecasting, which considers the association and interaction between the variables involved, such as radio anomalies, the proton density of the solar wind preceding strong vibration. The analysis is based on the collection of about 800 data of vibration of range equal to or greater than 6 occurred on a global scale between 2012 and 2014, related to solar wind and radio anomalies detected before the disastrous Tohoku vibration of March 11, 2011. To discuss the data has been applied the deductive logic, which allows to make predictions from the hypotheses, formulated in a mathematical way. In this context, the mechanisms of triggering vibration are hypothesized with an interaction of electrical nature, at subatomic scale. The outcome of the research has shown encouraging results on the application of the prediction formula, reinforced by the control of its parameters.Item Possibility and measurement of earthquake prediction based on trend study of total electron content (tec) of earth's Ionosphere(MM Publishing, 2020) Нагорний, Володимир В`ячеславович; Нагорный, Владимир Вячеславович; Nahornyi, Volodymyr Viacheslavovych; Panda, A.; Pandova, I.The article discusses a new breakthrough methodology for forecasting events and phenomena that are diverse in their physical nature. The article uses the total electron content trends (TEC) of the ionosphere as initial data for earthquake forecasting. The total electron content of the Earth’s ionosphere is a good indicator of its state and its dynamics. It has been found that the most effective for earthquake forecasting are TEC indicators, recorded regularly during the several years preceding the forecasted earthquake.