Introduction. Traditional machining methods for these components often face challenges related to high labor intensity, tool wear, and insufficient surface quality, especially when producing tooth gaps. The thermofrictional treatment method offers a promising alternative to improve efficiency and surface characteristics without compromising structural integrity. The aim of this study is to evaluate the feasibility and effectiveness of thermofrictional treatment in machining the tooth gaps of large-modular cylindrical gears, replacing the conventional rough milling stage with a more resource-efficient approach. Materials and methods. Experimental trials were conducted on 40Х steel blanks. Surface roughness was measured using a portable profilometer TR 100. The process was modeled using DEFORM 3D software. Cutting parameters included feed rates (S) from 0.13 to 2.08 mm/rev and spindle speeds (n) from 200 to 2000 rpm. Results. Experimental findings revealed that feed rate is the dominant parameter influencing surface roughness. Increased feed results in higher surface irregularity, while excessive reduction reduces processing efficiency. Higher spindle speed improves surface finish due to more stable chipformation. Optimal conditions were identified as S = 0.52 mm/rev and n = 2000 rpm. Simulation results showed that increasing spindle speed raises contact temperature (up to 2660°C) while reducing the depth of thermal penetration into the workpiece, resulting in localized thermal effects. Discussion. The study confirms that thermofrictional processing effectively replaces conventional rough milling, offeringacceptable surface quality and reduced manufacturing complexity. The thermal behavior at the interface plays a crucial role in achieving the desired surface integrity and must be controlled to avoid subsurface damage. Conclusion. Thermofrictionaltreatment using a specially developed disc cutter can be effectively applied to machine tooth gaps in large-modular cylindrical gears, achieving the required surface roughness while improving process efficiency. Resume. The method provides a viable and energy-efficient alternative to traditional machining operations for heavy-duty gear components. These results can be applied in gear manufacturing and repair facilities serving the mining and heavy equipment sectors. Further research should focus on analyzing hardness changes in the treated layer and optimizing heat distribution for various steel grades. © 2025, North Caucasian Institute of Mining and Metallurgy, State Technological University. All rights reserved.

In the article there is a review of world experience in the study of pollution of water bodies, including plastic particles. To date, the problem of plastic pollution has become global. Plastic pollution is a relevant and relatively new direction. The term "plastic" is a generalized name for the family of synthetic polymers. Plastic is a highly demanded material, which is used in all sectors of the economy for various reasons such as low cost, durability, etc. At the same time, it has a negative impact on the environment and impacts humans and living organisms by entering the food chain. Scientists classify plastic into micro- and macro-plastic according to particle size. Analysis of the study of plastic pollution leads to the conclusion that the smaller the size of the particles, the greater their impact on the pollution of water bodies. The difficulty of assessing plastic pollution is the lack of a unified recommended methodology. The study of MP problems in continental water bodies, including its possible concentrations, interaction with hazardous chemical compounds and impact on biota, is just beginning to be investigated. In this situation, it is reasonable to recommend the inclusion of micro- and macroplastics as one of the components of the program for monitoring the qualitative condition of surface waters. © 2023, National Academy of Sciences of the Republic of Kazakhstan. All rights reserved.

Cellulose-based composite materials have attracted increasing interest among scientists working on developing energy-storage materials with unique properties. In the present study, an aerogel was synthesized from sunflower seed husk (SFH) to form microcrystalline cellulose (MCC), the hydrogen (H2) sorption potential of which was then investigated. The effect of MCC concentration on the nitrogen sorption capacity of the aerogel samples obtained was assessed based on comparison with other like materials. As per the results of BET analysis, the aerogel with an MCC concentration of 3% was determined to be microporous, with a specific surface area of 3000 cm2/g, average pore diameter of 29.7 nm, total pore volume of 0.44 cm3/g, density of 166 kg/m3, and porosity of 95%. It was found that at a temperature of 77 K and up to 1 bar, MCC3/polyacrylamide (PAm) aerogel can sorb up to 0.8% hydrogen. Additionally, the results of SEM analysis revealed a microporous surface morphology, while FTIR analysis showed that the hydroxy groups in the MCC molecule and the amino groups in the PAm molecule form hydrogen bonds with each other. The results of the research indicate that such an aerogel has potential for use as a material for H2 storage, and appears to be more ecologically friendly than the metal hydrides used in many H2 fuel cells and storage containers, the end-of-life processing of which remains a relatively unexplored issue. Generally, cellulose is considered to be a highly desirable material from both ecological and economic perspectives. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.

The study presents a scenario analysis of the long-term dynamics of the water level of Lake Balkhash, one of the largest closed lakes in Central Asia, taking into account climate change according to CMIP6 scenarios (SSP2-4.5 and SSP5-8.5) and socio-economic factors of water use. Based on historical data (1947–2021) and a water balance model, the contribution of surface runoff, precipitation and evaporation to the formation of the lake’s hydrological regime was assessed. It was established that the main source of water resources for the lake is the flow of the Ile River, which feeds the western part of the reservoir. The eastern part is characterized by extremely limited water inflow, while evaporation remains the main element of water consumption, having increased significantly in recent decades due to rising air temperatures. Increasing intra-seasonal and interannual fluctuations in water levels have been recorded: The amplitude of short-term fluctuations reached 0.7–0.8 m, which exceeds previously characteristic values. The results of water balance modeling up to 2050 show a trend towards a 30% reduction in surface inflow and an increase in evaporation by 25% compared to the 1981–2010 climate norm, which highlights the high sensitivity of the lake’s hydrological regime to climatic and anthropogenic influences. The results obtained justify the need for the comprehensive and adaptive management of water resources in the Balkhash Lake basin, taking into account the transboundary nature of water use and changing climatic conditions. © 2025 by the authors.

Critical infrastructure has a paramount role in socio-economic development, and its disruption can have dramatic consequences for human communities, including cascading impacts. Assessing critical-infrastructure exposure to multiple hazard is therefore of utmost importance for disaster risk reduction purposes. However, past efforts in exposure assessment have predominantly concentrated on residential buildings, often overlooking the unique characteristics of critical infrastructure. Knowing the location, type and characteristics of critical infrastructure is particularly challenging due to the overall scarcity of data and difficulty of interacting with local stakeholders. We propose a method to assess exposure of selected critical infrastructure and demonstrate it for Central Asia, a region prone to multiple hazards (e.g., floods, earthquakes, landslides). We develop the first regionally consistent exposure database for selected critical infrastructure and asset types (namely, non-residential buildings, transportation and croplands), assembling the available global and regional datasets together with country-based information provided by local authorities and research groups, including reconstruction costs. The method addresses the main known challenges related to exposure assessment of critical infrastructure (i.e., data scarcity, difficulties in interacting with local stakeholders) by collecting national-scale data with the help of local research groups. The analysis also includes country-based reconstruction costs, supporting regional-scale disaster risk reduction strategies that include the financial aspect. © 2024 Copernicus Publications. All rights reserved.

The article deals with the issues of transport provision of Almaty city by such type of public transport as metro. For this purpose, from the authors’ point of view, important indicators characterizing the accessibility of transport services by metro for the city residents were determined, such as: population coverage within the radius of transitional accessibility; daily passenger flow of metro by direction; average time loss while waiting for a train on the platform; average train speed; average travel time of a passenger to the intended station. In addition, in order to calculate some of the indicators, field studies were conducted directly at the metro stations. The results of the study may be of interest to all persons interested in the development of urban passenger transport. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

The worldwide trend in energy production is moving toward circular economy systems and sustainable availability of sources. Some advanced methods support the economic development of energy production by the utilization of waste biomass, while limiting ecological effects. The use of agro waste biomass is viewed as a major alternative energy source that expressively lowers greenhouse gas emissions. Agricultural residues produced as wastes after each step of agricultural production are used as sustainable biomass assets for bioenergy production. Nevertheless, agro waste biomass needs to go through a few cyclic changes, among which biomass pre-treatment contributes to the removal of lignin and has a significant role in the efficiency and yield of bioenergy production. As a result of rapid innovation in the utilization of agro waste for biomass-derived bioenergy, a comprehensive overview of the thrilling highlights and necessary advancements, in addition to a detailed analysis of feedstock, characterization, bioconversion, and contemporary pre-treatment procedures, appear to be vital. To this end, the current status in the generation of bioenergy from agro biomass through various pre-treatment procedures was examined in this study, along with presenting relevant challenges and a perspective for future investigations. © 2023 Elsevier Ltd

Water scarcity poses a significant global challenge, particularly acute in arid and semi-arid regions with limited freshwater resources and high agricultural water demands. This study investigated the impacts of recycled wastewater irrigation using hybrid poplar trees as a model crop in the Kyzylorda region, characterized by extreme climatic conditions and water scarcity. A randomized complete block design (RCBD) was employed to ensure robust comparisons between two irrigation treatments: the control using water from the Syrdarya River, and the experimental treatment involving biologically treated wastewater from the Kyzylorda Wastewater Treatment Plant. Chemical analysis revealed that the soil irrigated with wastewater exhibited higher pH levels (7.5 ± 0.3) compared to the control (7.0 ± 0.2), indicating increased alkalinity. Electrical conductivity, a measure of soil salinity, was significantly elevated in wastewater-irrigated soil (2.3 ± 0.2 dS/m) relative to the control (1.2 ± 0.1 dS/m), reflecting higher salinity levels. Moreover, organic matter content was substantially greater in wastewater-irrigated soil (3.5 ± 0.4%) compared to the control (2.1 ± 0.3%), suggesting enhanced organic enrichment. Nutrient levels, such as nitrogen (45 ± 5 mg/kg), phosphorus (30 ± 4 mg/kg), and potassium (189 ± 16 mg/kg) were markedly higher in the wastewater-irrigated soil compared to the control (27 ± 3 mg/kg, 15 ± 2 mg/kg, and 121 ± 10 mg/kg, respectively), highlighting the nutrient-rich nature of recycled wastewater. Seasonal dynamics in flora and fauna were also assessed. From January to March, both control and wastewater-irrigated plots exhibited a decline in species richness, reflective of winter dormancy. In January, for instance, control plots averaged 23 ± 4 species per square meter, whereas wastewater-irrigated plots had 18 ± 3 species per square meter. Fauna abundance followed a similar pattern, with both groups showing gradual increases from January to March, peaking in summer. The control plots consistently maintained higher fauna abundance levels compared to the wastewater-irrigated plots throughout the study period. Overall, this study provides insights into the complex interactions between recycled wastewater irrigation and soil health, crop performance, and ecological dynamics in arid environments. © (2024), (Polskie Towarzystwo Inzynierii Ekologicznej (PTIE)). All rights reserved.

The development of smart devices and the enhancement of the 5G network pose a challenge in the management of resources especially in the dynamic and high-density networks. This paper proposes a machine learning approach for the optimization of resource allocation for 5G Internet-of-things (IoT) networks. The framework integrates real-time data processing, dynamic routing and edge computing for the improvement of the network throughput and quality of service (QoS). The suggested methods have been developed and evaluated in MATLAB simulations have shown important enhancements in latency, bandwidth and energy efficiency. Through the overcoming the limitations of the conventional methods, this research offers the solutions for the resource allocation problem in the 5G-IoT networks which are scalable, adaptive and efficient. © 2025 IEEE.

In the pursuit of sustainable oil and gas resource extraction, the innovative integration of carbon capture, utilization, and storage (CCUS) technology has emerged as the most promising approach. During the CCUS process, intricate physicochemical interactions between the injected CO2, facilitated through various injection strategies (Water Alternative Gas: WAG/Continue Gas Injection: CGI) and the formation fluids and heterogeneous mineral assemblages within the reservoir trigger alterations in mineral structures, consequently impacting permeability and recovery factors, constituting a pivotal aspect. Precisely delineating and quantifying these interactions is paramount for optimizing process design and evaluating reservoir dynamics in the successful implementation of CCUS operations. This study has carried out qualitative and quantitative characterization of mineral heterogeneity, different pore types, and mineral combination characteristics from a low-permeability sandstone reservoir. Additionally, the effect on the physical properties of minerals from different development methods (WAG/CGI) was investigated using numerical simulation for CCUS applications. The results indicate that the saturated CO2 fluid selectively dissolves the potassium feldspar (orthoclase) in intergranular pores, while the intergranular pores are filled with illite and secondary precipitated clay minerals. It initially dissolves the sensitive mineral (ankerite) in the intergranular pores. The decrease of ankerite and increase of illite result from the prolonged contact period between saturated CO2 and minerals, which changes the mineral cementation to argillaceous type, thus affecting permeability in the context of CCUS. The spatial impact on reservoir physical properties depends on the spatial heterogeneity of the original sensitive minerals (ankerite, anorthite, illite, etc.) distributed in the study area. In the WAG scheme, the physicochemical interaction between saturated CO2 and reservoir minerals is more intense than in the CGI scheme for CCUS operations, significantly impacting cumulative production. © 2024 Sichuan Petroleum Administration