Перегляд за Автор "Lebedev, V. V."
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Документ Automatic control of temperature and power conditions during rough grinding of slabs(Національний технічний університет "Харківський політехнічний інститут", 2021) Tihenko, V.; Lebedev, V. V.; Chumachenko, T.The production of high-quality rolled products (slabs), the formation of its surface phase-structural composition, texture, stress state during rough grinding depends on the temperature in the area of contact between the wheel and the slab. During processing, due to geometric errors of the rolled surface, as well as due to local changes in hardness, periodic fluctuations of the instantaneous depth of cut occur, which can be determined indirectly by controlling one of the technological parameters, for example, the power spent on grinding, with subsequent recalculation it to online temperature values. The grinding temperature is described as a control object in the form of an aperiodic link. Computer simulation has confirmed the efficiency of the system for maintaining the specified temperature of slab grinding under various operating conditions that simulate the situations of real production.Документ Ceramic-inorganic polymer composites for protection against electromagnetic radiation mechanical properties designing(IOP Publishing Ltd, 2023) Lebedev, V. V.; Miroshnichenko, D. V.; Kryvobok, R. V.; Cherkashina, A. M.; Riabchenko, M. O.The possibility of designing mechanical properties of ceramic-inorganic polymer composites for protection against electromagnetic radiation is considered. As a result, the mechanical properties of polymer composite based on polyamide, modified with ceramic inorganic graphite-ferromagnetic fillers (silicon carbide, chromium oxide Cr2O3 and graphite) was received and optimized. The strength characteristics complex of ceramic-inorganic polymer composites with silicon carbide SiC, chromium oxide Cr2O3 and graphite content in diapason 5-15 % wt. were studied. It was established that the optimal strength characteristics can be received using binary modification of polyamide with ceramic-inorganic graphite-ferromagnetic fillers: polyamide 6 – SiC 10% wt. – Cr2O3 10% wt. and polyamide 6 – SiC 10% wt. – graphite 10% wt. Using mathematical modeling, it was established that the polyamide 6 – SiC 10% wt system is the most optimal for three-component complex modification with ceramic inorganic graphite-ferromagnetic fillers – Cr2O3 10% wt. – graphite 10% wt. By design experimental-statistical mathematical models in equal regressions, mathematical optimization of mechanical properties of polymeric ceramic-inorganic composites contains for protection against electromagnetic radiation was carried out. Designed polymer ceramic-inorganic composites for protection against electromagnetic radiation according to their strength characteristics can be used for modern radio absorbing materials production.Документ Comparative analysis of the impact of synthetic additives and phosphatide concentrate on the adhesive properties of road petroleum bitumen(ДВНЗ Український державний хіміко-технологічний університет, 2023) Lavrova, I. O.; Demidov, I. M.; Cherkashina, G. M.; Lebedev, V. V.; Zabiyaka, N. A.The adhesive properties of brand BND 60/90 road bitumen with the oxidized phosphatide concentrate additive were studied. It was shown that the oxidized phosphatide increases the adhesive properties of bitumen brand BND 60/90. Oxidized phosphatide concentrate can be recommended as cost-effective alternative to expensive synthetic cationic surfactants, which are now widely used as adhesives for road bitumen. Based on the results of laboratory tests, the mathematical analysis of the obtained data was performed. Comparative graphs were plotted, and Pearson’s correlation coefficients and the approximation reliability values were calculated. It was found that the optimal composition for creating effective bituminous compositions with an increased thermo-physical and adhesive characteristics is 0.6 wt.% of oxidized phosphatide concentrate.Документ Design and research of bituminous compositions modified by rubber brittle waste(Vasyl’ Stus Donetsk National University, 2022) Vinnyk, A. M.; Reuka, Y. V.; Myagkohlib, I. I.; Savchenko, D. O.; Lebedev, V. V.; Cherkashina, G. M.; Lavrova, I. O.Документ Design and research of bituminous compositions modified by rubber brittle waste(Національний університет цивільного захисту України, 2022) Cherkashina, A. N.; Lavrova, I.; Lebedev, V. V.; Tykhomyrova, T. S.Документ Design and research of eco-friendly coffee grounds filled polymer composites(Національний університет цивільного захисту України, 2020) Lebedev, V. V.; Tykhomyrova, Tetiana Sergiivna; Lozovytskyi, A.; Grigorova, T.; Litvinenko, Ie.; Avina, S. I.; Saimbetova, Zh.Документ Design and researching of biologically active polymeric hydrogel transdermal materials modified by humic acid(IOP Publishing Ltd, 2023) Lebedeva, K. O.; Cherkashina, A. M.; Tykhomyrova, T. S.; Savchenko, D. O.; Lebedev, V. V.Biologically active polymer hydrogel transdermal materials based on gelatin, sodium alginate, modified by humic acids, were designed and researched. Literature review was carried out and it was proved that humic acids using is perspective for the functional effect on the biologically active polymer hydrogel transdermal properties. It has been found that effective processes for receiving biologically active polymer hydrogel transdermal materials based on gelatin, hydroxypropyl cellulose and sodium alginate can be carried out in different humic acids concentration while achieving an effective increase in hydrogel polymers structuring processes. It can be seen efficiently increasing biologically active polymeric hydrogel transdermal materials based on gelatin and sodium alginate conditional viscosity and the specific electrical conductivity with an increase of humic acids content: from 114 to 135 sec and from 2350 to 2850 mkS/cm, respectively. Humic acids modification in biologically active polymeric hydrogel transdermal materials based on gelatin and sodium alginate caused structure formation with high density, and resistance and with larger agglomerates in hydrogels. It was found that the gelatin-based biopolymer hydrogels modification by humic acids makes it possible to receive biologically active polymeric hydrogel transdermal materials with higher swelling degree. It is shown that the application of new biologically active polymeric hydrogel transdermal materials based on gelatin and sodium alginate modified by humic acids allows improving the skin moisture-lipid balance. From the initial values of 34-36% moisture and 8-10 skin fat, they increase to 58-66% and 52-60%. So, designed polymer hydrogel based on gelatin, sodium alginate, modified by humic acids, are transdermal materials with good properties.Документ Epoxy jewelry as STEM project(Copissaurio Repro – Centro Imp. Unip. Lda. Campus de Gualtar, Portugal, 2020) Minakova, K. O.; Tykhomyrova, T. S.; Lebedev, V. V.Документ Hybrid eco-friendly biodegradable construction composites modified with humic substances(Odessa State Academy of Civil Engineering and Architecture, 2022) Lebedev, V. V.; Miroshnichenko, D. V.; Mysiak, V. R.; Bilets, D. Yu.; Tykhomyrova, T. S.; Savchenko, D. О.Obtaining hybrid eco-friendly biodegradable structural composites was considered. The aim of this work was to determining the properties of hybrid eco-friendly biodegradable construction composites modified with humic substances. Hybrid eco-friendly construction composites were obtained on the basis of bioplastic polylactides with the addition as a filler of coffee grounds with a polyfractional composition within a particle size of 0.5 mm to 1 mm and a hybrid modifier – humic substances from brown coal. Hybrid ecofriendly construction composites were obtained by extrusion of pre-prepared raw materials in a single-screw laboratory extruder at a temperature of 170–200 °С and an auger rotation speed of 30–100 rpm. Investigated impact strength, breaking stress during bending, melt flow index (MFI) and melting temperature of hybrid ecofriendly biodegradable structural composites modified with humic substances. Optimization studies have been carried out to determine the most effective composition of new ecofriendly structural composites based on bioplastics of polylactides, coffee grounds waste and humic substances of three different types. Researching data together with the data of impact strength, allows us to make assumptions about the possibility of forming a variety of products from structurally composite material, herewith a composition with a coffee content of 50 % by mass. deserves a special attention. The data show an increase the impact strength and the breaking stress during bending a hybrid modification of ecofriendly biodegradable construction composites based on polylactide, coffee grounds waste and humic substances in 2.5 times, with optimal in terms of strength characteristics is the content of coffee grounds at 50 % wt. and 0.5 % by mass humic substances with the highest content of volatile substances and the lowest content of carbon. For such hybrid ecofriendly biodegradable construction composites based on polylactide, coffee grounds waste and humic substances, the MFI is characterized by 3.1 g/10 min. and the processing temperature range is 182–188 °C. It is shown, that the designed hybrid eco-friendly biodegradable structural composites modified with humic substances can be used in the production of high-strength structures and elements for engineering purposes.Документ Identification of properties of recycled high-density polyethylene composites when filled with waste mud solids(Технологический центр, 2019) Rykusova, N.; Shestopalov, Oleksii; Lebedev, V. V.; Tykhomyrova, T. S.; Bakharieva, GannaРозглянута можливість збільшення об'ємів утилізації відходів буріння шляхом використання їх в якості наповнювача для виготовлення полімерного композиційного матеріалу. В результаті проведених досліджень проведена модифікація вторинного поліетилену високої густини відпрацьованим буровим розчином у вигляді частинок високодисперсного наповнювача. Одержані полімерні композити вторинного поліетилену високої густини, які були наповнені відходами бурового виробництва із вмістом відходів до 30 %. В результаті дослідження виявлені закономірності зміни ударної в'язкості, руйнуючої напруги при вигині і водопоглинання від вмісту твердої фази відпрацьованого бурового розчин у(ТФВБР) у вторинному полімері. Показано, що при введенні до складу вторинного поліетилену високої густини ТФВБР у вигляді частинок високодисперсного наповнювача відбувається значне підвищення їх міцності без значного погіршення водопоглинання (до 2,9 % при наповненні відходами до 30 %). Встановлено, що оптимальний вміст відходів бурового виробництва у складі полімерних композитів на основі вторинного поліетилену високої густини складає 20 % мас. При цьому досягаються максимальні значення ударної в'язкості і руйнуючої напруги при вигині для композиції з ТФВБР на основі бентонітової глини до 63,3 кДж/м2 і 200,1 МПа, а для композиції з солевою ТФВБР до 38,1 кДж/м2 і 207,4 МПа відповідно. Одержані полімерні композити за своїми експлуатаційними характеристиками перевершують відомі аналогічні полімерні матеріали з використанням таких наповнювачів як тальк і каолін. Це дозволяє рекомендувати сумісну утилізацію відходів буріння і полімерних відходів.Документ Identifying the properties of epoxy composites filled with the solid phase of wastes from metal enterprises(Технологический Центр, 2019) Shestopalov, Oleksii; Briankin, Oleksandr; Lebedev, V. V.; Troshin, Olexiy; Muradian, Arsen; Ocheretna, Valentyna; Yaremenko, NadiiaThe article addresses the issue related to the disposal of dust from steel industry as a reinforcing filler for epoxy composites. The polymer composition of "cold welding" that has been developed and studied includes epoxy dian oligomer, amine hardener and the filler – finely dispersed waste of metals. Polyethylene polyamine was used as a hardener in order to improve heat resistance and strength characteristics. Manganese triacetate was used in order to decrease the temperature and reduce the time of curing. The possibility was established to dispose of finely dispersed metal-containing waste from metallurgical production to be used a filler for epoxy composites of cold curing. It was revealed that the optimal content of dusts from foundries in the composite is at the level of 45–60 %. At this content, there is the highest impact resistance at the level of 40–50 MPa and a softening temperature in the range of 170–190 °С. It was established that at an increase in the amount of a filler from 40 % to 70 %, the cross-linking degree increases by 88 % to 98 %, respectively. However, at the content of the filler less than 45 % or exceeding 60 %, the impact resistance of the resulting composites decreases. At the content of a filler in the composite less than 45 %, the cause of low values of impact resistance and softening temperature could be the low cross-linking degree, less than 90 %. A decrease in these properties of composites at the content of the filler exceeding 60 % could be associated with the formation of a heterogeneous structure of filler. In the compositions with the highest performance characteristics, there is an optimized content of the filler and catalyst. Using a hardener and a curing catalyst in quantities of 3–3.5 and 1.5–2 %, respectively, makes it possible to shorten curing time by up to 2 hours. In general, the resulting epoxy composites are superior in their performance to known cold-curing analogs. The dependences of impact resistance, softening temperature, and cross-linking degree on the content of waste in the composite were derived, which make it possible to calculate the optimal formulation for composites depending on the required properties.Документ Improvement of PVC composition for manufacture of packaging film by extrusion method(Національний технічний університет "Харківський політехнічний інститут", 2021) Derius, D. V.; Cherkashina, G. M.; Lebedev, V. V.Документ Influence investigation of structuring methods on the sorption properties of polymer composite materials(International Science Group, 2022) Cherkashina, A. N.; Lebedev, V. V.; Klimchuk, S. O.Документ Influence of structuring methods on the heat resistance of PCM(Національний технічний університет "Харківський політехнічний інститут", 2022) Cherkashina, G. M.; Lebedev, V. V.; Derius, D. V.; Klimchuk, S. O.Документ Optically transparent melamine-formaldehyde polymers modified with proton acceptors(Institute for Single Crystals, 2009) Lebedev, V. V.; Blank, T. A.; Avramenko, V. L.; Eksperiandova, L. P.; Mishurov, D. A.; Titskaya, V. D.; Shadrikov, A. S.Investigation of reaction water binding in melamine-formaldehyde polymers with proton accepting compounds has shown that the use of dymethil sulfoxide in 1/1 (v/v) ratio provides preparation of optically transparent materials. Introduction of dymethil formamide and dymethil sulfoxide improves the main characteristics of the material, but modification with dymethil formamide reduces the polymer transparency.Документ Polymeric composition for manufacture of foamed products(Волинський національний університет ім. Лесі Українки, 2021) Cherkashina, G. M.; Rassokha, O. M.; Lebedev, V. V.; Lavrova, I. O.Документ Properties of polymers obtained from humic acids(ТОВ "Планета-Прінт", 2021) Zhang, Xiaobin; Lebedev, V. V.; Miroshnichenko, D. V.; Pyshyev, S.; Savchenko, D.One of the most important areas of modern research in the field of polymer materials is the field of obtaining and studying the properties of polymer hydrogels. Hydrophilic polymers with large volumes of water absorption and storage are known as hydrogels, or super absorbents.Документ Research of structuring processes of epoxy and acrylic polymer composite(MDPC Publishing, 2022) Cherkashina, A. N.; Lebedev, V. V.Документ Sorption studying of environmentally friendly polymeric materials(Національний університет цивільного захисту України, 2021) Lebedev, V. V.; Tykhomyrova, T. S.; Lozovytskyi, A.; Grigorova, T.; Filenko, O.; Cherkashina, A.Документ Study of aging of sealing compounds structured in different ways(International Science Group, 2022) Cherkashina, A. M.; Lebedev, V. V.; Derius, V. V.