
Purpose. To justify and develop the theoretical bases of the formation and operation of the container technology for moving mining mass from quarries, which ensures a reduction of economic and energy costs, as well as damage to the environment during the extraction of mineral resources. Methodology. The work used complex research methods, including analysis and scientific synthesis of scientific and technical information; theoretical research; methods of mathematical and computer modeling, and design developments. Findings. The analysis of existing technologies for openpit mining and the current state of mining indicates an urgent need to develop new resourcesaving technology and environmentally friendly technologies for moving rock mass for openpit mining. A new technology for container transportation of rock mass in containers is proposed without the construction of additional transport communications in the quarry and has technological and energysaving advantages. Originality. The scientific novelty of the research consists of an integrated and systematic approach to assessing the energy efficiency and environmental safety of the proposed set of equipment for container technology for transporting rock mass. Practical value. In this work, special attention is paid to the problem of the formation and effective use of a new resourcesaving and environmentally friendly container technology for moving rock mass from deep quarries. These advantages are simultaneous excavation of rocks, transportation of rocks over the shortest distance, low container packing ratio, and mobility of a complex of lifting machines, which will reduce energy consumption and the cost of transporting rock mass. A transport complex has been developed to ensure the reliable operation of lifting and transport machines.

This paper presents the results of determining the parameters of tritium transfer processes in lithium ceramics Li2TiO3 under reactor irradiation conditions. Analysis of sections with a short-term decrease in reactor power allowed numerical determination of the Arrhenius parameters of tritium diffusion (pre-exponential factor and activation energy) based on comparison with in situ experimental data. The obtained values of activation energy (70.2–74.7 kJ/mol) and pre-exponential factor (0.9–2.1 × 10−8m2/s) demonstrate growth with increasing fluence, which is explained by the accumulation of radiation defects in ceramics. A linear dependence was established between D0 and Ea, corresponding to the Mayer–Noldel rule. Unlike previously conducted studies based on a phenomenological approach to assessing only the activation energy of diffusion, in this study, a complex model that takes into account temperature gradients, tritium generation, its diffusion, and release from the surface was used. The applicability of such an integrated approach to the analysis of in situ reactor experiments with lithium ceramics was confirmed, and allowed us to estimate changes in the tritium transfer parameters in lithium ceramics Li2TiO3 depending on the irradiation time. © 2025 by the authors.

Purpose. To analyze the development of landslide processes in the village areas, study the causes of the destruction of the coastline of Lake Alakol, and develop recommendations for coastal protection measures. To assess the impact of key geological, hydrological, and climatic factors on the intensity of abrasion processes and the dynamics of the coastline. Methodology. The methodology includes a comprehensive approach. Monitoring of the shoreline was conducted, covering the measurement of erosion speed and direction, evaluation of sediment volumes, analysis of changes in the coastline and geomorphological features. Computer modeling was used to predict destructive processes, considering multiple factors such as hydrological conditions, lithological composition of rocks, and climatic conditions. Retrospective analysis of long-term observation data and photographs revealed patterns in the development of shoreline changes. Findings. The changes in the shoreline of Lake Alakol are related to the complex interaction of natural and anthropogenic factors. The main causes of shoreline destruction were identified, including active landslides, wave erosion, and changes in the hydrological regime. Measures for shore strengthening were proposed: installation of breakwaters, slope reinforcements, planting vegetation, creation of artificial beaches, and other engineering measures. A program for predicting coastal destruction using mathematical models has been developed, which allows for effective planning of measures to protect them. Originality. The scientific novelty of this work lies in the integration of modern monitoring, analysis, and modeling methods to study the dynamics of coastal processes. This approach provides a deeper understanding of the causes of shoreline destruction and contributes to the development of optimal engineering solutions. Practical value. Recommendations are developed that can be used for strengthening the shores of Lake Alakol, as well as preventing exogenous geological processes (shoreline abrasion, landslides, landslips, collapses, gully formation, etc.) at other water bodies. © Alzhigitova M. M., Tileuberdi N., Zapparov M. R., Auyelkhan Y. S., Abdisseiit E. S., 2025

The paper presents an algorithm for planning agricultural field surveying routes in the presence of obstacles, designed to address precision agriculture tasks. Unlike classical methods, which are typically limited to straightforward zigzag (Zamboni) traversal and basic perimeter-based obstacle avoidance, the proposed algorithm accounts for heterogeneous unmanned aerial vehicles (UAVs) of varying types, ranges, costs, and speeds, along with a mobile ground platform that enables drone takeoff and landing at multiple points along the road. The key innovation lies in a two-stage optimization procedure: initially, a random set of field partitions into multiple sub-polygons with predefined area proportions (considering internal obstacles) is generated. Subsequently, the optimal partitioning is selected, and based on this, a genetic algorithm is applied to optimize flight parameters, including flight angle, entry points, composition, and sequence of drone launches, and the ground platform route. This approach achieves more localized coverage of individual field segments, with each segment serviced by an appropriate drone type, while also enabling flexible movement of the ground platform, thereby reducing unnecessary flights. This brings down the price of the coverage by 10–30% in some cases. The concluding section discusses future directions, including the incorporation of three-dimensional terrain considerations, dynamic factors (such as changing weather conditions and drone stoppages due to technical issues), and automated collision avoidance in intersecting route segments. © 2025 by the authors.

In comparison with unfoamed polymers, polymer foams find extensive application in various civil and industrial fields such as packaging, sports equipment, absorbents, and automotive components due to their advantages of lightweight, high strength-to-weight ratio, excellent insulation properties, high thermal stability, high impact strength, toughness, and long fatigue life. The preparation of conventional polymer foam typically necessitates the incorporation of chemical foaming agents into the polymer, raising environmental issues, which pave the way for the utilization of supercritical fluids. Supercritical fluids exemplified by supercritical carbon dioxide or supercritical nitrogen, are renowned for their environmentally friendly and non-toxic characteristics, thus offering a viable alternative to conventional chemical foaming agents. Supercritical fluids exhibit gas-like diffusion and liquid-like density, offering excellent plasticization effects on polymer melts. This substantially reduces the melt viscosity, melting point, and glass transition temperature of the polymer, facilitating the preparation of uniformly distributed, smaller-sized, and higher-density microcellular foams. This review first provides an overview of the characteristics of supercritical fluids and commonly used supercritical fluid foaming agents. Subsequently, the dissolution, diffusion, and interactions of supercritical fluids in polymers were discussed, followed by a focused elucidation of the cell nucleation (homogeneous and heterogeneous) and growth (island model and cell model). Finally, the application of supercritical fluids in the foam manufacturing techniques is highlighted, including batch foaming, extrusion foaming, and injection foaming, while emphasizing the challenges that still exist in polymer foaming. © 2023, The Author(s), under exclusive licence to Springer Nature Switzerland AG.

Enhancing heat transfer rates while concurrently reducing pressure drop will significantly enhance the energy efficiency of industrial heat exchangers, thereby contributing to a cleaner and more sustainable environment in the future. This study explores the fluid flow of a novel combination solution in a helical heat exchanger under a constant heat flux across various Reynolds numbers (5000–17000) aiming to uncover synergies that enhance heat transfer efficiency while reducing drag for the first time. Two key performance metrics, namely Drag Reduction (DR) and Heat Transfer Enhancement (HTE), along with the thermal effective index, are introduced to evaluate both hydrodynamic and thermal characteristics. Under turbulent conditions, an aqueous solution containing Anionic PAM (100–500 ppm) obtains a noteworthy 43% DR at 500 ppm. Simultaneously, a colloidal solution of nano-SiO2 (500–3000 ppm) in deionized water demonstrates an impressive 47% HTE at 2000 ppm. Furthermore, this study introduces two novel terms, “heat transfer enhancement synergy” and “drag reduction synergy,” marking their debut in the literature. The investigation extends to exploring four Nano-SiO2_PAM combinations which is the novelty of the study, revealing an outstanding 93.3% synergy in HTE. Precisely, at Reynolds 14,000, the synergy between 100 ppm PAM and 2000 ppm SiO2 (named comb.20 as the best combination) attains a remarkable 73.76% in DR, showcasing a noteworthy thermal effectiveness reaching approximately 200%. Even for comb.20, at Reynolds 5000, the synergy achieves a notable 133.33% in DR and 76.22% in HTE, which is quite significant. This result is attributed to a complex formation that elongates the polymer chain due to the presence of nanoparticles around the polymer chain, effectively damping eddies. Furthermore, a novel set of correlations is proposed for the prediction of the Nusselt number of the aforementioned solutions, demonstrating a remarkable agreement with experimental data with a maximum error of 24%.
Targeting vascular endothelial growth factor receptor (VEFGR) and its co–receptor neuropilin–1 (NRP–1) is an interesting vascular strategy. tLyp–1 is a tumor–homing and penetrating peptide of 7 amino acids (CGNKRTR). It is a truncated form of Lyp–1 (CGNKRTRGC), which is known to target NRP–1 receptor, with high affinity and specificity. It is mediated by endocytosis via C–end rule (CendR) internalization pathway. The aim of this study is to evaluate the importance of each amino acid in the tLyp–1 sequence through alanine–scanning (Ala-scan) technique, during which each of the amino acid in the sequence was systematically replaced by alanine to produce 7 different analogues. In silico approach through molecular docking and molecular dynamics are employed to understand the interaction between the peptide and its analogues with the NRP-1 receptor, followed by in vitro ligand binding assay study. The C-terminal Arg is crucial in the interaction of tLyp-1 with NRP-1 receptor. Substituting this residue dramatically reduces the affinity of this peptide which is clearly seen in this study. Lys-4 is also important in the interaction, which is confirmed via the in vitro study and the MM-PBSA analysis. The finding in this study supports the CendR, in which the presence of R/K-XX-R/K motif is essential in the binding of a ligand with NRP-1 receptor. This presented work will serve as a guide in the future work pertaining the development of active targeting agent towards NRP-1 receptor. © 2022 Elsevier Inc.

Centrifugal pumps are widely used in various industries such as manufacturing, agriculture and firefighting due to their versatility. They are based on the principle of creating centrifugal force by a rotating impeller, which ensures the movement of liquid from the suction point to the discharge point. Design methods are based on the theory of one-dimensional homogeneous flows and hydraulic laws. This study focuses on designing impellers for centrifugal pumps with the aim of creating an efficient design that meets performance and head requirements. To achieve this, fundamental principles of fluid mechanics and empirical equations for one-dimensional flows are utilized. The culmination of the work is the study and analysis of various methods for calculating the hydraulic characteristics of centrifugal pumps, which helps to identify their advantages and limitations and select the most suitable method for a particular task. Efficient application of such methods simplifies and speeds up the pump design process, enabling engineers to develop new models and improve existing ones more quickly.

This study investigates the impact of widely used mineral fillers in self-compacting concrete compositions applied in vibration-free reinforced concrete production technology, as a means of enhancing rheological characteristics and cost-effectiveness. Three distinct types of mineral fillers, including the well-studied fillers microsilica and metakaolin, as well as the lesser-explored filler Kazakhstani natural opal-chalcedony opoka, are examined in this research. In addition to the evaluation of conventional rheological and performance properties of concretes containing these fillers, the internal processes within the cement–filler matrix are analyzed. This includes X-ray phase analysis and microstructural examination of cement hydration products in combination with a superplasticizer and each of the three minerals. The findings confirm the potential for optimizing the rheological parameters of the concrete mixture by substituting up to 15% of the cement with mineral fillers, achieving optimal viscosity and workability. It is established that compositions with the addition of microsilica and metakaolin have a more homogeneous structure, mainly represented by low-basicity calcium hydrosilicates of the CSH(B) type, along with an increase in compressive strength of up to 10%. The addition of these mineral fillers to C30/35 strength class self-compacting concrete resulted in improved frost resistance up to F300, a reduction in volumetric water absorption by up to 30%, and a decrease in shrinkage deformations by 32%. The developed SCC compositions have successfully passed production testing and are recommended for implementation in the operational processes of reinforced concrete product manufacturing plants. © 2025 by the authors.

The disposal of drilling mud waste from uranium mining operations poses a significant environmental challenge due to their toxicity and potential for contamination. The investigation aims to test different powder flocculants of approximately the same molecular weight and their interaction with waste drilling mud and to identify the flocculant with the best qualities for further use in the industry. The empirical method was applied in the study, during which experiments were carried out on a sample of drilling mud, along with quantitative and statistical analyses. Flocculation was carried out using a Couette cylindrical flocculator. Three flocculants, namely A-150, N-100, N-300, and C-494, from a single manufacturer, Kemira, were also chosen for the study. As a result of the laboratory experiments, it was determined that N-300 was the best flocculant, giving optimum results in the study. It has been found to be capable of separating the drilling mud into water and solids fractions as quickly as possible. In addition, the use of ultra-flocculent treatment to improve the intensity of the sedimentation process of clay suspensions is a prerequisite. Thus, the drilling fluids treated in this way are more environmentally friendly, increase productivity and duration, and reduce production costs. The novelty lies in systematically evaluating various powder flocculants and applying ultraflocculation, a sophisticated hydrodynamic treatment method, to optimize the separation process.
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