A significant number of properties of composites based on polycarbonates, unfilled and filled with 10 - 30 % short glass fibers of E-glass, treated with 3-(aminopropyl) triethoxy silane, were studied. The purpose of the study is to determine whether these composites can be used to manufacture impellers for centrifugal pumps. It was found that with increasing the amount of filler, the properties of polycarbonate composites change as follows: in general, the physico-mechanical parameters (all modules, tensile strength), stiffness and flexural strength increase, maximum deformation, as well as elastic and impact resistance decrease somewhat. The volume and surface resistivity decrease, the coefficient of thermal conductivity increases. The main reason for these changes in the properties of the composites is the good adhesion at the polymer matrix-fiber interphase which is attributed to the strong physical interaction due to silane used and as a result of the good wetting of the fibers from the polycarbonate matrix and improved compatibility. Based on the results obtained, it can be concluded that polycarbonate composites, filled with 10 - 30 % short glass fibers can be successfully used for the production of centrifugal pumps impellers, as they meet a significant number of requirements for materials with such application. © 2022,Journal of Chemical Technology and Metallurgy.All Rights Reserved

В статье рассматривается применение аддитивных технологий в производстве оснастки из полимеркомпозитных материалов, приведены особенности технологического процесса Fused Granular Fabrication (FGF). Представлен процесс создания матрицы для гибки V-образным паза под углом 90° из композитного материала, на основе полимерной матрицы с добавлением стекловолокна для повышения износостойкости. В процессе технологического процесса с использованием композитной матрицы были выявлен тот факт, что пружинение заготовок приктически минимально. В статье приведены результаты сравненения параметров обработки материала на стальной и композиционной полимерной матрицах. По результатам экспериментов очевидно, что для обработки материала с относительно большим внутренним радиусом предпочтительнее использовать полимерную матрицу, поскольку это позволяет снизить усилие давления на 10–20 % при получении одинакового качества продукции Экспериментальные результаты показывают, что использование композиционных полимерных матриц для гибки в мелкосерийном производстве позволяет уменьшить усилие давления, а также снизить стоимость производства по сравнению с традиционными металлическими инструментами. В заключении выделяются преимущества и ограничения применения таких матриц, а также рекомендации для оптимизации процесса гибки и дальнейшего использования в промышленности.

Pyrite tailings from operating industrial facilities, beyond their primary component, frequently contain valuable base metal minerals (e.g., Co, Ni, Cu) that are in constant demand and are critical for 'green energy' technologies. Despite the comparatively low concentration of Ni and Co in these tailings, their overall reserves are potentially significant. The objective of this study was to investigate the recovery of nickel, cobalt, and copper from leach sulfuric solutions derived from nickel-cobalt-bearing pyrite concentrate using solvent extraction. It was established that selective metal recovery necessitates the preliminary precipitation of iron as jarosite at a controlled pH. From the resultant iron-free solution, selective copper extraction was achieved using Acorga 5640 in kerosine at a pH range of 2.8–3.0. This was followed by the co-extraction of Ni and Co using Cyanex 272 combined with TBP at a pH of 5.0. To obtain high-purity cobalt and nickel sulfate, the optimal solvent extraction scheme was determined to be 2E+1Sc+1S (2 Extraction stages + 1 scrabbing stage + 1 Stripping stage). As a result of this research, pure iron hydroxide, along with marketable nickel, cobalt, and copper sulfates, were successfully recovered. Further concentration of the final cobalt sulfate solution requires a subsequent sorption process.

The article presents the results of the use of rapid prototyping technology when modifying the impeller of a centrifugal pump in order to increase efficiency. As a result of the implementation of the technology, the influence of parameters such as the printing speed of the main layers, the printing speed of the current layers, the thickness of the layers on the geometric accuracy of printed products was studied. According to the results of experiments, it was revealed the effect of the feed rate on the OZ axis, an increase in speed will lead to lower surface quality, higher roughness. The distance between the layers is 0,15 mm/s, getting a roughness of Ra 6,3 microns, and in the right case we used a distance of 0,05 mm/s between the layers, getting a roughness of Ra1,6 microns. The article presents the results of the analysis of the effect of exposure time and exposure time in the UV chamber on the hardness of printed products. The article presents a method for determining and compensating the geometry of prototypes based on reverse engineering technology based on the use of an optical scanner. The tests of a centrifugal pump with a prototype of a modified wheel confirm the need for such innovations as rapid prototyping to shorten the design cycle of new products, as well as reduce the cost of their development.

With interest in camel milk growing due to its nutrients and biologically active compounds, research into methods of processing and drying it is crucial. In recent decades, extensive studies have explored its chemical composition and health benefits with a focus on drying techniques and their effects on its properties. This review systematically summarizes the available literature on camel milk drying processes and their effects on its chemical composition with a view to shortening the drying time. To achieve this goal, we meticulously reviewed numerous studies published between 2014 and 2024 to identify optimal drying methods that maximize the preservation of camel milk’s nutrient components and bioactive compounds. Our analysis revealed significant findings: freeze drying preserves nutrients better than spray drying, but is less efficient. Spray drying, while faster, tends to compromise some nutritional values. Conclusively, optimizing drying parameters can improve production efficiency and nutrient retention.

In this work, we studied the kinetostatics and stress-strain state of the links of the actuator mechanism of the exoskeleton of the lower limb. The main results of the work include obtaining reaction values in the kinematic pairs of the mechanism, analysis of the stress-strain state of the links in various positions of the mechanism in the support phase. In the load transfer phase, only the gravity forces of the links and the human foot are applied to the mechanism. Key parameters describing the stress-strain state of the links in this phase were obtained. Particular attention is paid to determining the position at which maximum stresses arise in the sections of the links. A comparative analysis of existing exoskeleton designs and new functional capabilities was carried out: a closed kinematic chain, rational structural synthesis, a combined-type actuator mechanism with decomposition of motion by degrees of mobility and with a gravitationally independent topology, which will minimize the number of active power drives. The results of the study can be used to optimize the design of the exoskeleton, as well as to develop recommendations for the use and adjustment of the mechanism in order to reduce stress in the links and increase the efficiency of the device.

Typical leg exoskeletons employ open-loop kinematic chains with motors placed directly on movable joints; while this design offers flexibility, it leads to increased costs and heightened control complexity due to the high number of degrees of freedom. The use of heavy servo-motors to handle torque in active joints results in complex and bulky designs, as highlighted in the existing literature. In this analytical study, we introduced a novel synthesis method with analytical solutions provided for synthesizing the lower-limb exoskeleton. Furthermore, we proposed a mathematical model of multicriteria optimization; as a result, we obtained several lower-limb exoskeleton mechanisms comprising only six links, well-suited to the human anatomical structure, exhibit superior trajectory accuracy, efficient force transmission, satisfactory step height, and having internal transfer segment of the foot.

Полезная модель относится к области применения в устройствах хранения электроэнергии, в частности к способам переработки сельскохозяйственных отходов, таких как рисовая шелуха, для получения аморфного диоксида кремния (SiO₂) высокой чистоты. Разработка эффективного способа переработки растительного сырья — рисовой шелухи — с целью получения аморфного диоксида кремния, обладающего высокой удельной поверхностью, осуществляется за счет предварительной очистки, гидротермальной обработки в щелочной среде и последующее химическое осаждение, причем гидротермальная обработка осуществляется в водном растворе гидроксида натрия (NaOH) при концентрации 2 моль/л, процесс проводится при температуре 150 °C в течение 60 минут с применением микроволнового нагрева частотой 2,45 ГГц и мощностью 500 Вт, обеспечивающим равномерный нагрев и ускоренное растворение кремнезёма, и осаждение аморфного диоксида кремния из силиката натрия осуществляется добавлением раствора серной кислоты (H₂SO₄) концентрацией 4 моль/л до достижения pH 8, далее полученный гель промывают дистиллированной водой до нейтрального pH и сушат при температуре 110 °C до постоянной массы. Технический результат, достигаемый при реализации полезной модели: сокращение времени и энергозатрат процесса, повышение экологичности и воспроизводимости, получение высокодисперсного аморфного SiO₂ с высокой степенью чистоты и развитой пористой структурой.

This paper proposes a robot designed for automated routine or emergency disinfection in closed premises. The robot is related to the combined type robots. The robot consists of two functional parts: a universal mobile platform (lower part) and a disinfector (upper part), which, if necessary, can be freely moved by personnel on 4 wheels. In the initial position, the upper part of the disinfection robot is at the charging station. The mobile robot drives up to the disinfector, «hooks» it (puts it on itself) and moves along the planned route. The upper part of the disinfector will have its own independent intelligent system, separate from the mobile robot, which, when a person is recognized, stops liquid disinfection: in this case, the UV lamps turn through 180°, the cylindrical body closes and ventilation of the disinfected air from the enclosed space is turned on. In addition, liquid disinfection is only enabled when detecting beds, tables and chairs. With the spray nozzles located at a height of 400 mm, the disinfector can carry out a simultaneous combined treatment of rooms with equipment and furniture, including high-quality processing of the lower surfaces of tables, chairs and beds. To improve the functional characteristics of robotic disinfectors and to simplify their design, a multifunctional robotic disinfector has been proposed. It was found that the result is achieved by the fact that in a multifunctional disinfection robot containing a mobile cart with an autonomous positioning and navigation system, a disinfection platform with a disinfection liquid spraying system and UV lamps with reflectors installed on it, the disinfection platform will have its own autonomous control and power systems.

Бұл мақала MATLAB бағдарламалық қамтамасыз ету ортасында Open MANIPULATOR-X ашық бастапқы роботтық платформасын пайдаланып, төрт еркіндік дәрежесі бар роботты қолдың алға және кері кинематикалық талдауын жүзеге асырды. Мәселені салыстырмалы түрде оңай шешу үшін тікелей және кері кинематикаға арналған алгоритмдер әзірленіп, симуляция жүргізілді. Жүйенің верификациясы және валидациясы жүзеге асырылып, траектория жоспарлау, қателерді талдау және құрылымдық оңтайландыру әдістері қолданылды. Нәтижелер робот қолының траекториясын жоспарлау және робот дизайнын құрылымдық оңтайландыру сияқты болашақ зерттеулер үшін теориялық негіз қалады.. MATLAB платформасы арқылы кинематикалық модельдеу, симуляция және алгоритмдерді жазу, тексеру және верификация, траектория жоспарлау, қателерді талдау және құрылымдық оңтайландыру сияқты роботика жұмыстарда қолданылады. Бұл мәселе адамдардың робототехникалық қабілеттерін жақсарту мен инновацияларға жетуіне көмектеседі.