Використання рідких жирових відходів закладів ресторанного господарства як альтернативної сировини для харчової промисловості, біомедич-них і фармацевтичних застосувань та виготовлення біопалива

There is an active search for alternative types of raw materials for the needs of the national economy. Fossil fuel reserves are noticeably depleted, the ecological condition of the environment is deteriorating, and at the same time, the amount of industrial waste that needs to be disposed of is increasing. The number of polymers for production based on natural raw materials and the need for them for the food industry, biomedical and pharmaceutical applications is constantly growing. About 250,000 liters of used vegetable oil and other fats are generated every week in catering establishments of Ukraine. The largest share belongs to spent frying fats. A significant volume of promising raw materials ends up in the sewage system. The resources of the treatment plants are excessively depleted. Also, emissions of spent fatty raw materials cause enormous damage to the environment. A study was conducted on: the dynamics of changes in quality indicators of sunflower oil during prolonged heating; evaluation of the quality indicators of the samples of the studied spent fats; dynamics of changes in cooking fat quality indicators during prolonged heating; the dynamics of changes in the quality indicators of frying fat during prolonged heating; the physico-chemical indicators of the quality of samples of experimental used fats were investigated. The possibility of using spent frying fats for the production of targeted products, which is a promising resource for the synthesis and production of polymer materials and secondary raw materials in the processes of the technical sphere and the production of biofuel, was investigated. The use of spent liquid fats as a raw material for the production of diesel fuel is appropriate, however, among the tested samples, heated sunflower oil is the least suitable. Spent deep-frying and cooking fats showed a fairly high resistance to long-term heating and after contact with a hot surface are characterized by acceptable values of thermo-oxidative stability, namely 46.5 and 44.1 %, respectively.Відбувається активний пошук альтернативних видів сировини для потреб народного господарства. Запаси викопного палива помітно виснажуються, погіршується екологічний стан навколишнього середовища і одночасно зростає кількість промислових відходів, що потребують утилізації. Харчова промисловість, біомедицина та фармацевтична сфера формують постійно зростаючий попит на полімерну продукцію, виготовлену на основі природної сировини. Щотижня у закладах харчування України утворюється близько 250 тисяч літрів відпрацьованої рослинної олії та інших жирів, найбільша частка в яких належить відпрацьованим фритюрним жирам. Значний обсяг перспективної сировини потрапляє в каналізацію, надмірно виснажуючи ресурси очисних споруд підприємств. Також, викиди відпрацьованої жирової сировини наносять колосальний збиток навколишньому середовищу. Досліджено динаміку змін показників якості соняшникової олії при тривалому нагріванні; проведено оцінку показників якості зразків досліджуваних відпрацьованих жирів; вивчено динаміку зміни показників якості кулінарного жиру при тривалому нагріванні; проаналізовано динаміку зміни показників якості фритюрного жиру при тривалому нагріванні; досліджено фізико-хімічні показники якості зразків дослідних відпрацьованих жирів. Досліджено можливість використання відпрацьованих фритюрних жирів на виробництво цільових продуктів, які є перспективним ресурсом для синтезу та виробництва полімерних матеріалів і вторинної сировини у процесах технічної сфери та виготовлення біопалива. Використання відпрацьованих рідких жирів як сировини для виробництва дизельного пального є доцільним, однак серед досліджених зразків найменш придатною є гріта соняшникова олія. Відпрацьовані фритюрний і кулінарний жири виявили досить високу стійкість до тривалого нагрівання і після контакту з гарячою поверхнею характеризуються допустимими значеннями термоокиснювальної стабільності, а саме 46,5 і 44,1 %, відповідно

Model for the high cycle corrosion-fatigue damage of machine parts

The report is dedicated to a problem of the phenomenological specification statement of corrosive fatigue damage in the small stresses conditions. As the baseline equation usage the E.K.Pochtenny’s equation is offered, which one will to the greatest degree be matched with experimental results in a high-cycle corrosion fatigue conditions for steel specimens and full-scale parts. Also this equation is in a basis of the whole complex of designed methods of an estimation of durability and residual operational life of accountable of members of constructions operating in high-cycle fatigue conditions. The disadvantage of the equation is asymptotically lower branch, coming nearer to endurance strength, of a curve of fatigue, which one in corrosive conditions does not correspond to results of experiments. For overcoming this disadvantage the two-parameter equation for lower branches of a curve of a corrosion fatigue is offered. The calculus of arguments is spent with the help of the system of the nonlinear equations. The result of applying of the equation is showed on an actual example of a pump rods curve of fatigue

Metal-ion zeolites obtained by chemical and mechanochemical methods as Fenton-like catalysts for health applications

One of the critical steps for the development and health applications of inorganic nanoparticles is to exhibit high efficiency without inducing toxicity. In this work, metal-ion zeolites were developed to be used as Fenton-like catalysts for health applications. ZSM-5 and BEA zeolites were modified through chemical and mechanochemical methods to obtain nanomaterials with tuned particle size and texture. Characterization data showed that the modified materials kept the crystal structure although some textural modifications occurred. Upon Mn2+loading, the catalytic behavior was evaluated by Fenton-like reaction using physiological and mild acidic conditions (37 ºC, pH=7.4 and 6.4 and 50 M H2O2), since these conditions are relevant to various pathological environments. MnBEA series showed the best results by Fenton-like reactions, revealing the great potential of metal-zeolite nanomaterials for health applications.V.I. and A.R.B. thank for the PhD grants, UI/BD/152219/2021 and SFRH/BD/141058/2018, respectively. ASM thanks FCT for the Assistant Researcher contract CEECIND/01371/2017 (Embrace Project). This work was supported by FCT (Foundation for Science and Technology, Portugal) by the projects: UIDB/00100/2020. UIDP/00100/2020 and LA/P/0056/2020, CQ/UM (UID/QUI/0686/2020), CEB (UIDB/04469/2020) and LABBELS (LA/P/0029/2020), and Instituto Politécnico de Lisboa (IPL) through Project IPL/2022/ZeoMed ISEL.info:eu-repo/semantics/publishedVersio

Determining the Influence of the Condition of Rock-destroying Tools on the Rock Cutting Force

At present, the most common tools for drilling operations are those rock-destroying ones that are equipped with cutting elements made from polycrystalline diamonds (PDC) and diamond carbide inserts (DCI). Given this, it is a relevant task to study the influence of the degree of wear of cutting elements on the strength and energy parameters of the process of rock destruction. In order to determine this influence, we have experimentally investigated the cutting process involving a single cutter under laboratory conditions. The mean values of the cutting force components (circular ((Рz) and normal (Рy)) have been established at the cutting depth 0.5; 1.0; 1.5; and 2.0 mm, at a varying degree of the cutting element wear (a flat of 0; 5.0; and 8.0 mm). We have determined the magnitude of cutting work and the specific energy of rock destruction. At a cutting depth of 0.5 mm, with an increase in the cutting element wear rate from 0 to 8 mm, the magnitude of work grows from 0.06376 to 0.121 N∙m. At a cutting depth of 2.0 mm, the magnitude of work increases from 0.624 to 3.603 N∙m. The energy intensity of the rock destruction process increases, with an increase in the cutting depth from 0.5 to 2.0 mm, from 3.88 kJ/m2 to 11.66 kJ/m2 for a sharp cutter. Based on the study results, we have built dependence charts of the average values of the cutting force components and its normal component (Рy) on cutting depth and the cutting element wear degree. The results obtained have shown a significant influence of the size of the wear flat on the increase in the process strength parameters, which is the basis for regulating a wear degree of cutting elements during drilling. We have established the tendency towards a growth in the resultant force and specific work of rock cutting by a cutting element with an increase in wear degree. This makes it possible to determine, based on the indicators of fluctuations in the instantaneous strength values during drilling of wells, or based on a change in power, the wear degree of the cutting elements, and to predict the probability of their destructio

Molecular hybridization as a tool for designing multitarget drug candidates for complex diseases

Molecular hybridization is a well-exploited medicinal chemistry strategy that aims to combine two molecules (or parts of them) in a new, single chemical entity. Recently, it has been recognized as an effective approach to design ligands able to modulate multiple targets of interest. Hybrid compounds can be obtained by linking (presence of a linker) or framework integration (merging or fusing) strategies. Although very promising to combat the multifactorial nature of complex diseases, the development of molecular hybrids faces the critical issues of selecting the right target combination and the achievement of a balanced activity towards them, while maintaining drug-like-properties. In this review, we present recent case histories from our own research group that demonstrate why and how molecular hybridization can be carried out to address the challenges of multitarget drug discovery in two therapeutic areas that are Alzheimer\u2019s and parasitic diseases. Selected examples spanning from linker-to fragment-based hybrids will allow to discuss issues and consequences relevant to drug design

Optimum Conditions Determination of Methyl Methacrylate Obtaining Over Tungsten-containing Catalyst

The main common methods of methyl methacrylate producing are acetoncyanohydrin method and oxidation of isobutylene and tert-Butanol. Because of the significant drawbacks of these methods, it is important to develop new, alternative ways of methyl methacrylate obtaining, one of which could be aldol condensation of methyl propionate with formaldehyde in the gas phase. The actual task for today is to find out effective catalysts for this process.For this aim, methyl propionate condensation with formaldehyde was studied in the presence of B2O3-P2O5-WO3/SiO2 catalyst, which previously has showed high activity in the condensation of propionic acid with formaldehyde to methacrylic acid. The paper also investigates the influence of methanol on the side reaction of methyl propionate hydrolysis; it was found that adding methanol causes a slight increase in MMA selectivity, but the yield of unsaturated products decreases, and therefore adding methanol to the reaction mixture for the MP condensation with FA over B2O3-P2O5-WO3/SiO2 catalyst is impractical. The optimum conditions for MP condensation with FA, namely temperature 653 K and contact time 12 s were found. Under these conditions, in the presence of B2O3-P2O5-WO3/SiO2 catalyst with an atomic ratio of components B:P:W 3:1:0.6 respectively total yield of MMA and MAA was 31.91% while their total selectivity was 32.3%

Fatigue longevity and residual life evaluation procedure of bulky parts with the help of local models

Для більш точної оцінки довговічності та залишкового ресурсу великогабаритних конструкцій запропоновано використовувати модель у вигляді “вирізки” із небезпечної зони чи вузла конструкції, яка повинна повністю імітувати конструкцію і технологію виготовлення небезпечної зони. Схема навантажування і напружений стан моделі має відповідати схемі і стану небезпечної зони. Для більш точної оцінки залишкового ресурсу деталі чи конструкції запропоновано використовувати моделі з реальними корозійними та механічними пошкодженнями, одержаними в процесі експлуатації чи їм рівними. Розроблено конструкцію стенду для випробувань таких моделей, яка дозволяє проводити випробування в широкому діапазоні геометричних параметрів жорстким навантажуванням на консольний згин з регулюванням асиметрії циклу та амплітуди деформації. Для вирішення задачі узгодження напруженого стану моделі та реальної конструкції використано метод скінченних елементів (МСЕ) та програмні засоби параметричної оптимізації в середовищі Ansys. Подальші дослідження буде спрямовано на експериментальну перевірку та вдосконалення даної методики на відповідальних великогабаритних елементах конструкцій особливо з критичним терміном експлуатації, де проблема оцінки залишкового ресурсу та його прогнозу є першочерговою.The fullest and precise information on a residual resource of members of constructions can be received at fatigue field tests with holding of the scheme of operation loading. But such trials of large-sized constructions, to which one treat also pipes of large diameters are connected to large methodical and technological difficulties, demand considerable material inputs and time. For more precise estimation of a residual resource of mains it is offered to use a method of local simulation and the tension of model completely respond the scheme and state of a dangerous zone. The conventional methods of manufacture of a stress raiser V- of a similar type and further cultivation of a fatigue crack do not meet the requirements to local model of pipes with corrosive and mechanical damages. Therefore it is offered to use models with actual corrosive and mechanical damages, whether obtained on-stream by it equal. It will enable precisely to evaluate a residual resource of a construction. For the coordination of a tension of local model and actual pipeline the finite element method and software of a parameter optimization in environment Ansys utilized. Obtained dependences are in a ground of mining of the fixture for trials of local models