The key objective of this study is to determine the effect of interphase boundaries, the formation of which is caused by the variation of Li2ZrO3/MgLi2ZrO4 phases in lithium-containing ceramics based on lithium metazirconate, on the resistance to near-surface layer destruction processes associated with irradiation with He2+ ions. During the observation of the deformation effects that have an adverse impact on the volumetric swelling of the near-surface layers of ceramics, the thermal expansion factor caused by high-temperature irradiation was considered, simulating conditions as close as possible to the operating conditions of these materials as blankets for tritium propagation. During the studies conducted, it was established that an elevation in the contribution of MgLi2ZrO4 in the composition of ceramics leads to a rise in resistance to deformation swelling caused by structural distortions of the crystal lattice, due to a decrease in the effect of thermal expansion, alongside the presence of interphase boundaries. The established dependencies of the change in the hardness of the near-surface layer of the studied ceramics made it possible to establish the kinetics of softening caused by the deformation distortion of the crystalline structure, as well as to determine the relationship between volumetric swelling and softening (change in hardness) and a decrease in crack resistance (change in the value of resistance to single compression).

Additive manufacturing technologies can offer a cost-effective alternative to the production of metal parts of complex geometric shape compared to traditional production or expensive methods of melting powder coatings. In this work, the starting materials were developed by adding 75 % by volume to 316 L stainless steel powder and 25 % by volume from LDPE materials as a binder. Methods of burning and sintering were carried out in a hydrogen atmosphere at a temperature of 1387°C. The resulting metal sample was described mechanically and microstructurally. After sintering the metal samples have a powder size of ~ 7 μm, a level of 250 MPa and a nanoindentation hardness of 4.87 GPa, which are the characteristic features of burnt steel.

Due to the high level of disability and death caused by heart diseases worldwide, the problem of combating cardiovascular diseases is becoming more and more important and relevant. In fact, one of the leading causes of death worldwide has long been cardiovascular disease, according to the World Health Organization. Among heart diseases, the most dangerous to life is myocardial infarction. In connection with the rapid morbidity, early diagnosis of this disease is one of the topical problems of modern public health care. At present, although there is a wide range of different statistical, math methods and computer tools for the processing of cardiological information, the task of increasing the accuracy of methods for the analysis of electrocardiograms and diagnostic tools in this field of study remained relevant. Taking into account the imperfect tools and systems for diagnosing heart diseases, as well as the human factor, the lack of a method that can help doctors to diagnose myocardial infarction early requires the development of new diagnostic information methods. This article presents a neural network analysis methodology for diagnosing myocardial infarction based on the joint analysis of direct and reverse signs of myocardial infarction from electrocardiographic information obtained from a portable cardiac analyzer.

Stressful events in students' and teachers' personal, academic, and professional lives are widespread. The paper discusses many effective methods and techniques for correcting and preventing stress that are simple to learn and practice. They give good results in working with children, adolescents, and youths in training and education. Some practices are more complex and require more attention and effort to understand and master them, but they also have broader capabilities in various situations. Therefore, training sessions aimed at training in the prevention and correction of (di)stress conditions are very relevant and necessary. The results showed that there is a conscious and urgent need for students to reduce anxiety and stress, including ways to deal with learning stresses. Stress management can and should be structured and systematically organized, including in the instrumental sense: students need to be taught how to manage stress and themselves, increase their resistance to stress (resilience), and be trained to use different coping techniques with anxiety, as appropriate. In an empirical study, representatives of other groups of students from three Kazakh universities answered questions from three author's stress questionnaires. According to the respondents, the study results showed that students need knowledge about stress. The study showed the urgent need for special educational and training seminars, lectures, and even courses on (di)stress and physical, mental, and moral injuries and coping with them. Such classes are needed to help schoolchildren and students cope with stress and avoid problems with moral, mental, and physical health to prevent other negative consequences of school and related strains. © 2023 by the author.

In this study, a new design of a hydroturbine was developed, modelled, and constructed. The unique features of this turbine design required a thorough investigation and optimization process to enhance hydroturbine performance. The paper discusses numerical and experimental results obtained on the hydroturbine. The optimal angle of attack for the inlet flow direction has been computed from numerical modelling. Consequently, data on velocity, pressure, lift, and drag forces along the blade have been obtained. The study also takes into account the operation of the hydroturbine under non-rotating and rotating rotor modes. Performance metrics such as head, torque, hydraulic power, hydroturbine power, and efficiency were then calculated based on water discharge. These performance calculations were conducted using COMSOL Multiphysics, employing Direct Numerical Simulation and k-epsilon methods. Numerical calculations offer a cost-effective approach to reducing the financial burden associated with material costs for manufacturing hydroturbine prototypes.

The article presents an innovative approach to the restoration and stabilization of weak soils, using the example of the Turkestan region, characterized by an arid climate and degraded soil cover. The main goal of the study was to develop and experimentally validate a biostabilization technology aimed at improving the physico-chemical and engineering-geological properties of soils through environmentally safe compositions. This technology addresses challenges such as erosion, low bearing capacity, and land degradation, which are especially critical in arid regions. The research involved an engineering-geological analysis of soils using laboratory and computational methods. Evaluated parameters included humus content, mobile phosphorus, nitrogen, exchangeable bases, water retention, and resistance to erosion. Experimental results showed that vermicompost significantly improves soil structure and geotechnical stability. Potassium polyacrylamide enhances water retention, reducing the risk of deformation and settlement. Lime-sulfur broth strengthens surface horizons and reduces wind erosion, although its impact on mechanical properties requires further study. The proposed biostabilization methods effectively improve the geotechnical characteristics of weak soils, increasing their resistance to erosion and enhancing their suitability for engineering applications such as foundation stabilization, slope reinforcement, and land restoration. These technologies are especially relevant in arid climates, where soil degradation is widespread. The study's findings can be applied in geotechnical engineering, engineering geology, and sustainable agriculture to support environmentally responsible land use and the restoration of degraded areas.

Hexavalent chromium Cr (VI) compounds present in ilmenite concentrate not only pose significant environmental hazards due to their toxicity but also complicate further processing, interfering with technological operations in industrial production. The high chromium content in ilmenite concentrates hinders their conversion into titanium-containing slag, necessitating the removal of chromium ions to permissible residual levels to produce titanium dioxide. In this study, various sorbents were investigated for the removal of chromate ions from the industrial effluents generated during ilmenite concentrate processing. The sorbents examined included natural and modified diatomite, activated carbon, taurite (shungite), and the ion-exchange resin Lewatit M500. The structures of both natural and modified diatomite were analyzed using scanning electron microscopy (SEM). It was determined that natural diatomite samples consist of diatom frustules of various shapes and their fragments, with structural element sizes ranging from submicron dimensions to 50 µm. A mathematical analysis of the sorption data for hexavalent chromium ion removal from solutions was performed. The results demonstrated high sorption efficiencies for Lewatit M500 (98.34%) and diatomite modified with iron compounds (98.95%). The findings suggest that diatomite is a promising sorbent for chromate ion removal from wastewater due to its availability and potential for chemical modification.

Microfluidic organs-on-chips or microphysiological systems (MPS) are promising tools that can potentially replace animal testing in drug development. MPS are platforms with microchannels seeded with certain organ cells used to emulate in vivo environments in laboratory conditions. Among them, platforms seeded with lung cells called lung-on-chip devices can evaluate the influence of toxic particles, gases, and chemicals on lung tissue in vitro. Lung-on-chip devices allow the mimicry of healthy lung conditions and a wide range of diseases (asthma, cancer, autoimmune, infections). This review focuses on the use of electrospun nanofiber membranes as a functional basement membrane which plays a central role in the development of lung-on-a-chip platforms. Here, we briefly introduce microfluidic devices, MPS, and lung-on-chip devices. Existing basement membrane models, such as thin-film and gel-based membranes, and their challenges/disadvantages are discussed. Next, the concepts of electrospinning and nanofiber membranes are introduced. Finally, the nanofiber membranes used in lung-on-chip devices are reviewed. Implementation of different polymer materials used to synthesize the nanofiber membranes and different methods for incorporation of the membrane inside the device are discussed. Electrospun nanofiber membranes provide good mechanical properties, allow transmigration of the immune cells, and withstand the physiological strain without affecting the cell viability.