The challenge of a good quality drinking water supply to southeastern Kazakhstan’s local population from far-away natural surface water sources motivates groundwater utilization from local aquifers. To prevent groundwater resource deficits, artificial groundwater recharge is needed. To this end, infiltration and clogging processes were evaluated through comprehensive field research in southeastern Kazakhstan’s typical river drainage basin (Aksu experimental site). The infiltration scenario included constructed mini pools and their typical soil profile clogging and silting processes. The local aquifer unsaturated and upper saturated zones underwent a detailed study of water balance, hydrodynamic setting, and filtration properties. The research results suggest that the infiltration rate decreased from 15 m/day until the saturation steady state and remained at 0.75 m/day until the end of the experiment. In summer, clogging layers with thicknesses ranging from 3 mm for the clayey silt layer to 6 mm for muddy clay began to form at the mini pools nearly one month after the test began. During infiltration, the mini pools’ upper soil layer dirt-holding capacity varied from 3.72 to 5.25 kg/m2. The field study results serve as a factual basis for artificial replenishment system design and groundwater replenishment methodology optimization in southeastern Kazakhstan and similar regions. © 2022 by the authors.

One of the global problems is environmental pollution by different biowaste. To solve the problem, biowaste must be recycled. Waste-free technology is also a way of saving exhaustible raw materials. Research on electrochemical energy sources is currently the most dynamically developing area of off-grid energy. Electrochemical capacitors can operate for a long time without changing performance, they have smaller dimensions, high mechanical strength, and a wide operating temperature range. These properties are effective energy-saving devices. Therefore, supercapacitors are widely used in various industries. This review discussed the methods of obtaining and the characteristics of biowaste-derived activated carbon and carbon–manganese oxide (AC-MnO2)-based supercapacitor electrodes. © 2022 by the authors.

Sodium-ion batteries (SIBs) offer several advantages over traditional lithium-ion batteries, including a more uniform sodium distribution, lower-cost materials, and safer transportation options. A promising development in SIBs is the use of hard carbons as anode materials due to their low insertion voltage and larger interlayer spacing, which improve sodium-ion insertion. Traditionally, hard carbons are made from costly carbon sources, but recent advancements have focussed on using abundant bio-waste, like coffee grounds. This approach reduces costs and helps manage global waste. This research investigates the electrochemical performance of bio-waste-derived hard carbons, which is significantly impacted by various pre-treatment methods. Techniques such as BET, XRD, TEM, and XPS are employed to examine the effects of pre-treatment variables, including washing solvents (organic, acidic, or distilled water), pre-oxidation temperatures, and post-heating processes. These factors influence the structural properties and purity of the hard carbon, impacting its effectiveness as an anode material in SIBs. A significant finding is a mesoporous hard carbon produced from coffee grounds that, after washing with distilled water, pre-oxidation at 150 °C, and thermal treatment at 1300 °C in argon, shows a 23% yield, a reversible capacity of 304 mA h g−1, and Initial coulombic efficiency of 78%. This study underscores the importance of pre-treatments in removing impurities and enhancing the material's sodium storage capabilities. © 2025 The Author(s)

Оқу құралы 5В070700 - "Тау-кен ісі" мамандықтарының Мемлекеттік стандарты және оқу бағдарламасымен сәйкес құрастырылған. Оқу құралы 10 бөлімнен тұрады. Оқу құралында еңбекті қорғау мен өндіріс қауіпсіздігінің негізгі жағдайлары, оның ішінде қауіпсіздік және еңбекті қорғау бойынша заңнама мен негізгі ережелер келтірілген, тау-кен ісінде еңбекті қорғауды ұйымдастыру, және тау-кен жұмыстарын қауіпсіз жүргізу мәселелері баяндалған. Тау-кен кәсіпорындарында кездесетін зиянды және қауіпті факторлар, олардың адамға әсері қарастырылған. Жазатайым жағдайларды зерттеу әдістері және оларды тергеп-тексеерудің құқықтық негіздері келтірілген. Тау-кен салаларында кездесетін газ жарылысы, тау-кен соққылары, өрт секілді апаттардың себептері мен ерекшеліктері, сонымен қатар олардың алдын алу жолдары зерттелген. Оқу құралының мақсаты - тау-кен саласында қауіпсіздік және еңбек қорғау саласындағы негізгі заңдылықтарды меңгеру. Сонымен қатар, тау-кен технологиялық үрдістерін атқарудағы қауіпсіздік талаптарымен танысып, оларды тәжірибе жүзінде жүзеге асыруға дайындау. Оқу құралы "Тау-кен ісі" мамандықтарында оқитын жоғары оқу орны студенттерінің білімдерін жетілдіруге ықпал етеді.

The paper presents the results of the influence on shrinkage deformations of the adopted composition during the drying and firing of ceramic bricks made using rice husk and ash of the combined heat and power plant of the city of Kyzylorda of the Republic of Kazakhstan. The optimal values of the husk additives content and ash from thermal power plants in the studied compositions were determined. Ash dumps from thermal power plants (TPP) create environmental tension and pose a great threat to both the environment and human health. It was found that the hydro-removal ash from the thermal power plant mainly consists of oxides of silica (45.45…46.37 %) and alumina (16.62…17.70 %), there are oxides of calcium (1.66…2.20 %), magnesium (0.86…1.12 %), iron (2.98…3.41 %) and alkali metals (0.80…1.04 %). The composition of ceramic bricks based on loess-like loam, rice husks, and ash from thermal power plants was studied. The charge composition of the raw components of the “clay, TPP ash, and rice husk” brick: clay is 71…75 %, TPP ash is 18…22 %, and rice husk is 2…6 % of the total mass of the components of the raw mixture of ceramic bricks. The compressive strength of fired ceramic bricks was 11…12 MPa. According to the results of experimental studies, it was found that the increased concentration of rice husks in natural mixtures is characterized by a stable increase in ceramic mass drying cracks. The increase in time until the appearance of drying cracks is 100 up to 160 sec. The resulting ceramic brick in accordance with the developed composition has a low weight, good thermal properties and meets the standard requirements for ceramic bricks according to GOST 530-2012 © 2022, Authors. This is an open access article under the Creative Commons CC BY license

Highlights: What are the main findings: Covalently crosslinked chitosan-based cryogel for removal of AgNPs AgNPs suspension stabilized by plant extract a model water contaminant having complex composition Water permeability of cryogels significantly affects AgNP adsorption efficiency and adsorption capacity What is the implication of the main finding? Maximum capacity for chitosan based cryogel prepared at −15 °C is 82 mg/g Low-cost adsorbent with high adsorption capacities to metal nanoparticles The discharge of nanoparticles into the environment, such as through industrial plants and municipal wastewater treatment plants, can pose a hazard to aquatic life. This study demonstrates the effective removal of silver nanoparticles (AgNPs) using a chitosan-based cryogel, which has potential applications in agriculture, as well as in water treatment or in industrial plants that discharge into environmentally sensitive water bodies. The adsorbent is economically viable, has high affinity toward metal nanoparticles, is biodegradable and biocompatible, and displays a good removal of nanoparticles. AgNP adsorption was monitored using UV/Vis spectroscopy and TEM analysis. SEM, nitrogen adsorption, TGA, and FTIR analysis were used for cryogel characterization. The BET model of nitrogen adsorption revealed a specific surface area of 7.7 m2/g for chitosan–glutaraldehyde (CHI–GA) cryogels. The elasticity modulus of the CHI–GA cryogel was estimated as 543 ± 54 kPa. The AgNPs were characterized by a negative charge (−38 ± 17 mV) and an average diameter of 64 nm with a polydispersity index of 0.16. The mechanism of AgNP adsorption involved electrostatic interactions between the oppositely charged surfaces of the cryogel and particles. The temperature of the cryogel preparation affected the water permeability and adsorption efficiency. CHI–GA illustrated a capacity of 63 mg/g at a flow rate of 0.8 mL/min under a solution pressure of 500–970 Pa. The increase in pressure of the model plant extract-stabilized AgNP suspension (14 mg/L AgNPs) to 3.42–3.9 kPa led to an increase in the water permeability rate to 10 mL/min and a significant decrease in the efficiency of particle removal. The CHI–GA adsorbent demonstrated up to 96.5% AgNP removal until the breakthrough point due to adsorbent saturation. The CHI–GA cryogel adsorbent (1 g) can be used for efficient filtering of about 4.5 L of contaminated water. © 2023 by the authors.

An important technological solution to the problem of plastic pollution is to replace traditional non-biodegradable polymers, which are the cause of environmental pollution, with biodegradable polymer materials with physical and mechanical properties. Searching for ways to reduce the biodegradation of self-degrading biopolymers and waste and reducing the cost of such materials, including the use of substances that can be analogs of biodegradable polymers for these purposes, is an urgent problem. The research work aimed to obtain a biodegradable biopolymer based on starch raw materials in the presence of various organic acids (citric acid, acetic acid, lactic acid) and plasticizers (glycerol, polyvinyl alcohol, nanomaterial). An effective material from products obtained based on various acids and plasticizers was selected. Improvement measures the the technology of manufacturing bioplastics was considered. Durable and cost-effective biopolymer was obtained, capable of re-processing and biodegrading biological waste, including starch-containing garbage. The resulting products have successfully passed all physical and chemical tests and are ready for mass production. To study of physical and chemical parameters of obtained biopolymers, scanning electron microscope and thermogravimetric analysis IR spectroscopy were implemented. Obtaining a biopolymer based on starch-containing garbage and using organic acids (acetic acid, lactic acid, citric acid) and a plasticizer that can serve as the main raw material in self-degrading biopolymers production. © 2023 Elsevier Ltd. All rights reserved.

This paper considers the issue related to the protection of buildings and structures against seismic influences and the prevention, exclusion, or reduction of seismic hazards. The catastrophic destruction of modern «earthquake-resistant» buildings in Turkey and Taiwan has shown that existing methods of strengthening and reinforcing structures are not perfect and require further study. Analysis of existing approaches to ensuring seismic resistance showed that seismic insulation and seismic suppression systems still do not have a scientific and technical justification for the effectiveness of their operation from the point of view of ensuring the stability of structures. The estimation-dynamic models of the «base-seismic insulation-structure» system developed to date do not always make it possible to simulate the joint work of their interaction during an earthquake and account for the transformation of the seismic impact on the structure. An alternative technique has been devised, a geotechnical seismic insulation screen, as a seismic insulation system that reduces the intensity of seismic loads on the structure and ensures its seismic resistance. In a specific example, the effectiveness of this seismic insulation system is confirmed. This seismic insulation technique in the form of damper screens is characterized by reliability and manufacturability in ensuring the seismic resistance of objects under construction. The results of computational and experimental modeling of the interaction of an earthquake-insulated structure with a ground base found that the values of axial forces and bending moments in a building with a seismic insulating screen are less than in a building without seismic insulation by 30–40 %. The geotechnical seismic insulation screen makes it possible to advance the development of new seismic insulation techniques and determine their effectiveness. This technique will also be effective when strengthening the base and seismic insulation systems of historical monuments, protecting them against seismic and dynamic influences © 2022. Authors. This is an open access article under the Creative Commons CC BY license

This study analyzes long-term changes in minimal streamflow in the Zhaiyk-Caspian Water Management Basin (WMB), Western Kazakhstan, under climate variability. Using extensive hydrometeorological datasets (monthly discharge and daily meteorological records) from 1940 to 2021, the research assesses trends in low-flow characteristics across 18 hydrological posts. The analysis distinguishes two climatic periods: climate stabilization (pre-1973) and climate change (1974–2021). The methodology integrates hydrological and statistical analyses, including minimal monthly discharges, low-flow durations, soil freezing depths, and thaw frequencies. Findings reveal a widespread increase in winter low flows—up to 5.2 times—due to reduced frost depths and more frequent thaw events, enhancing groundwater contributions. Conversely, summer-autumn flows declined in several rivers, with drying trends linked to rising air temperatures and precipitation deficits. This study offers a novel, regionally adapted methodology for characterizing minimal streamflow under climate change, providing critical insights for hydrological drought assessment and water resource planning in arid and semi-arid environments.

Electrospun fiber-based photocatalysts demonstrate significant potential in addressing global environmental and energy challenges, primarily due to their high specific surface areas and unique properties. This review examines recent advances in the application of these materials in photocatalytic processes, with a particular focus on water splitting and hydrogen production. The principles of the electrospun method are described in detail, along with the operating parameters, material characteristics, and environmental conditions that affect the fiber formation. Additionally, the review discusses the challenges, advantages, and future prospects of photocatalysts incorporating carbon materials, metals, semiconductors, and hybrid structures with improved performance. These materials have the potential to significantly improve the efficiency of hydrogen energy production, water purification, and CO2 recovery, highlighting their importance in engineering sciences. © 2024 by the authors.