Факультет митної справи, матеріалів, технологій та гостинності
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Item type:Наукова стаття, Intensification of the formation process of sodium sulfate-modified biocomposite materials based on the glutinous matrix(Kharkiv: Institute of Single Crystals of the National Academy of Sciences of Ukraine, 2023) Sadova, Oksana; Kashytskyi, VitaliiThe influence of the modifying additive (sodium sulfate) on the heat treatment regime of the biocomposition in the mold investigated in the article. The optimal content of sodium sulfate in the biocomposite material was determined. The influence of the content of the modifying additive on the compressive strength of biocomposites structured at different temperatures has studied. The optimal parameters of the thermal field temperature and the duration of heat treatment of the biocomposition for the given content of the additive, which provides the maximum values of mechanical characteristics, are determined. It established that the modifying additive with optimal content is able to increase the intensity of structuring of biopolymer binder. This consists in the rapid transition of the glutin binder from the gel state to the solid state with the formation of physicochemical bonds due to the removal of excess moisture under the influence of temperature. Fractograms of the fracture surface of biocomposites containing sodium sulfate analyzed.Item type:Наукова стаття, Influence of Additives Processed by Physical Fields on Tribotechnical Properties of Polymer Composites(2022) Sadova, Oksana; Kashytskyi, Vitalii; Melnychuk, MykolaThe influence of specific load on the intensity of weight and linear wear is determined in the article. The coefficient of friction and temperature in the zone of tribocontact of polymer composites, the components of which were processed in physical fields, were studied. The study of polymer composites with different content of components carried out at a constant sliding speed of 0.5 m/s. Epoxy resin and polyethylene polyamine hardener were used as a matrix to form polymer composites. To ensure increased heat resistance of the polymer matrix, a modifying additive (organosilicon varnish) was used. For the first time, the processing of organosilicon varnish in an electromagnetic field was applied, which allowed removing part of the solvent. Discrete aramid and glass fibers were used as reinforcing additives. For the first time, ultrasonic treatment of fibers in acetone was used, which allowed cleaning the surface of the fibers from contaminants and lubrications. Because of the use of the modifying additive and treated discrete fibers, the wear resistance of polymer composites increased by 30% due to the improvement of the adhesive interaction between the components of the system and the reduction of structural defects of the material. Removal of lubrication from the surface of the fibers and the solvent from the modifying additive increased by 0.1–0.15 the coefficient of friction of the polymer composites and will improve their service life. Friction polymer composite materials with high density and improved tribotechnical properties are designed for manufacturing brake systems of scooters.Item type:Наукова стаття, Хроматографічне визначення хімічного складу витягу яблучних чипсів(Київ, 2023) Шемет, Василина Ярославівна; Гулай, Ольга Іванівна; Климович, Олена СергіївнаВстановлено якісний склад витягу сушених яблук зелених (Голден, Муцу) і червоних (Флоріна, Айдаред) сортів методом газорідинної хроматографії з мас-селективним детектуванням. Чипси яблук отримано способом конвективного сушіння за температури +(63–70) °С до кінцевої вологості 6–8%. Водно-спиртовий витяг аналізували на газовому хроматомас-спектрометрі Shimadzu GCMS-QP2020 за повним іонним струмом (SCAN), діапазон сканування 40-1000 а.о.м. Обробку та ідентифікацію піків проводили на підставі даних відкритих джерел (NIST 2017 i Wiley 5th Edition). В досліджених зразках витягу яблук виявлено 30 характерних складових, серед яких переважають вуглеводи – моно- та дисахариди, їх похідні та продукти дегідратації та окиснення. У яблучному витягу присутні вищі жирні кислоти: н-гексадеканова кислота, тетрадеканова кислота, октадеканова кислота, олеїнова кислота. Виявлено сполуки, що утворюються у результаті сушіння (5-гідроксиметилфурфурол, 3,5-дигідрокси-6-метил-2,3-дигідро-4Н-піран-4-он), а також флавоноїди та антоціани, які виконують в організмі антиоксидантні та слабкі антибіотичні функції. Вітаміни дослідженим методом встановити не вдалося.Item type:Монографія, Chapter 5. Compositional analysis and potential of buckwheat and oats as functional food ingredients(Tallinn, 2025) Moroz, Iryna; Shemet, Vasylyna; Hulai, OlhaBuckwheat and oats are traditional, though not the most popular, crops with strong environmental adaptability. The bioactive substances in buckwheat and oats have a positive impact on human health, including antioxidant and anti-inflammatory properties and the ability to prevent cancer. In this work, a comprehensive analysis of buckwheat and oat powders was carried out, including sieve analysis, infrared spectroscopy (IR spectroscopy), X-ray fluorescence analysis (XRF) and gas chromatography with mass spectrometry (GC/MS). According to the results of sieve analysis, the highest content of fractions with a particle diameter of 1.1–0.5 mm was found: 41.76% for buckwheat powder and 52.56% for oat powder. The analysis of the IR spectra showed a similar chemical composition of both samples, including carbohydrates, proteins, fats and minerals. However, the buckwheat powder had a higher content of proteins and carbonyl compounds, and the oat powder had a higher content of polysaccharides. X-ray fluorescence analysis showed that both samples contain mainly C, H, P, S, K, Ca, Mn, Fe, Cu, Zn, but in different proportions. Buckwheat powder is characterized by a higher content of potassium and phosphorus, while oat powder has higher levels of calcium and manganese. The GC/MS method was used to identify 15 bioactive compounds in buckwheat powder and 18 in oat powder. Sucrose, palmitic acid, linoleic acid and phytosterols (gamma-sitosterol, campesterol) were found in both samples. Buckwheat powder has a higher content of antioxidants, in particular γ-tocopherol, while oat powder contains steroidal compounds and oxazole derivatives that may affect lipid metabolism. The study confirmed the unique nutritional profile of buckwheat and oat groats grown in Volyn. The results can be used in the field of functional food, pharmacology and nutrition to develop products with high biological activity.