One area that holds promise for nuclear energy advancement, which is the most attractive industry for eliminating the imbalance in the energy sector and reducing the world’s energy shortage for the long term, is the replacement of traditional uranium fuel with plutonium fuel. The focus on this research area is due to the growing concern of the world community about the problem of handling spent nuclear fuel, including its further use or storage and disposal. The main aims of this paper are to study the resistance of composite ceramics based on zirconium and cerium dioxide to the hydrogenation processes and subsequent destructive embrittlement, and to identify patterns of growth stability attributable to the occurrence of interfacial boundaries and changes in the phase composition of ceramics. Studies have shown that the main effects of the structural distortion of the crystalline structure of ceramics are caused primarily by tensile deformation distortions, resulting in the accumulation of radiation-induced damage. The formation of Zr0.85Ce0.15O2 tetragonal phase of replacement in the structure of ceramics results in a more than two-fold reduction in the deformation distortion degree in cases of high-dose radiation with protons. The evaluation of the alteration in the strength properties of ceramics revealed that the variation in the phase composition due to polymorphic transformation of the monoclinic Zr0.98Ce0.02O2 → tetragonal Zr0.85Ce0.15O2 type results in the strengthening of the damaged layers and the improvement of the resistance to radiation-induced embrittlement and softening. © 2023 by the authors.

Metal–semiconductor–metal back-contact perovskite solar cells (MSM BC PSCs) with interdigitated metallic electrodes show promise due to their simple structure. However, the power conversion efficiency (PCE) of experimentally obtained MSM BC PSCs is rather moderate. This could be attributed to suboptimal geometric dimensions of electrodes and the poor quality of the perovskite layers in reported devices. In this study, computer simulation methods are employed to investigate the influence of electrode and perovskite layer geometric and electronic parameters on the performance of MSM BC PSCs. The goal is to determine the optimum conditions for achieving high PCE. The findings reveal that the PCE of devices improves as the dimensions of electrodes become smaller. However, significant improvements in PCE are observed when the charge carrier diffusion lengths in the perovskite layer become longer and the work function difference between the electrodes becomes larger. The prediction based on optimal electrode and perovskite layer geometric and electronic parameters suggests that a PCE of around 26% can be achieved with MSM BC PSCs. Findings of this work unveils the hidden potential of MSM BC PSCs and can serve as a theoretical guide to optimize the structure and performance of experimental devices. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.

The growing reliance on fossil fuels is causing significant environmental issues, prompting the search for renewable energy sources. Hydrogen energy, which produces only water vapor, is a promising solution. This study focuses on developing an aluminum-doped SrTiO3 photocatalyst with dual cocatalysts (Rh/Cr2 O3 and CoOOH) for efficient photocatalytic water splitting. Using a simple chemical deposition method, high-purity and crystalline SrTiO3 was synthesized and thoroughly characterized. The results show that the modified SrTiO3 achieved significantly higher photocatalytic activity, with Rh/Cr2 O3/ SrTiO3 @Al/CoOOH producing 11.04 mmol g–1 h–1 of H2 and 4.69 mmol g–1 h–1 of O2. This work demonstrates the effectiveness of dual cocatalyst deposition and aluminum doping in enhancing photocatalytic performance by improving charge separation and reducing recombination. © 2024 The Author(s). Published by al-Farabi Kazakh National University.

The article presents trends in the hydrologic regime of the transboundary river Zhaiyk, and the in the context of anthropogenic and climatic changes. The water regime of rivers is characterized by reduction spring floods and increase the frequency of low-water runoff, especially in winter. The increase in winter runoff likely occurs as a result of climate-caused temperature and precipitation changes. Increasing average annual air temperature are evident both within seasons and from year to year between 1940 and 2019. The changes in runoff and water regime of transboundary Zhaiyk River basin have resulted in decrease in the annual and forecast reduction in river flows for future uses. © 2024, National Academy of Sciences of the Republic of Kazakhstan. All rights reserved.

The kinetics study of Pb2+ and Zn2+ ions adsorption by low-cost mixed Zr-Ca-Mg phosphates with a different Zr/(Ca + Mg) ratio was carried out, for the first time. The effect of chemical composition on adsorption characteristics of obtained adsorbents was established. It was shown that an increase of Ca2+ and Mg2+ cations content in the composition of Zr-Ca-Mg phosphate adsorbents contributed to an increase in the adsorption capacity to Pb2+ (3.82–4.76 mmol/g) and Zn2+ (2.60–4.13 mmol/g) ions. Such improvements in the adsorption capacities were due to the amelioration of the textural properties of adsorbents, so that ABET of adsorbents was in the range of 68–96 m2/g and Vdes BJH of adsorbent was in the range of 0.19–0.24 cm3/g. On the other hand, increase of Ca2+ and Mg2+ cations led to a high difference in solubility products of initial phosphates and spent adsorbents. Kinetic data of Pb2+ and Zn2+ ions adsorption revealed that the adsorption rate is controlled by film diffusion, intraparticle diffusion and chemical interaction, which was confirmed by the results of X-ray diffraction analysis of spent adsorbents and described by the pseudo-second-order model. The increase of zirconium content caused an increase in the rate constant of the pseudo-second-order of Pb2+ and Zn2+ ions adsorption. Intraparticle diffusion had a significant effect on Zn2+ ions adsorption. Due to the suitable kinetics parameters and sorption capacities of composite Zr-Ca-Mg phosphates for divalent metal ions, these sorbents can be recommended as effective materials for heavy metals removal. © 2023 Elsevier Ltd

The numerous cases of deformation of technogenic objects in the transport industry under increasing axial loads and speeds of motion aggravate the need to solve the problems of early recognition of the nature and causes of deformations of structural elements. The need for this is due to the fact that destructions and accidents, resulting from deformation processes, cause enormous economic, social and environmental damage, incomparable with the funds spent on protective measures. The object of the study in the article is a railway trestle, consisting of two spans of a ribbed reinforced concrete beam. Determination of the residual resource in terms of bearing capacity and load-carrying capacity of the railway trestle is the main task. The authors have obtained bending deformations (stresses), frequencies of natural vibrations and operating modes of structures of railway trestle spans. The damage degree of the railway overpass spans structures may also be judged by the deviation of the calculated values of the amplitude-phase-frequency characteristics (AFFR) from the standard values. The peculiarity of this research is the fact, that the natural frequencies of railway overpass vibrations are determined either by «tails» of experimental vibrograms (oscillograms) after the load release from the span structure. During the express-diagnostics of railway overpasses, the relative deformations (stresses) of girder spans in the middle of the span, the first frequency (period) of natural vibrations of girder reinforced concrete spans of railway overpasses are used as parameters characterizing the technical condition of the spans. The results of tests and examinations of overpasses to ensure their safe operation have been given © 2022, Authors. This is an open access article under the Creative Commons CC BY license

Lake Markakol is located in a metal-rich mountain area of Kazakhstan. Metal input into the lake water and in the bottom sediments can be expected. Lead, cobalt and nickel monitoring in both near-surface and deep-water layers and in bottom sediments was carried out using flame atomic absorption spectrometric analyses. Lead contamination of surface water ranging from 2.6 to 6.8 µg/L occurs in all water samples with the exception of the surface water layer. In the deep-water section concentrations reach up to 13.0–16.2 µg/L. Cobalt concentrations range from 36.8 to 67.5 µg/L in the surface layer and from 25.5 to 69.2 µg/L in the deep-water layer. High values of nickel were found in the surface and bottom layers of the water, ranging from 13.5 to 49.0 and 17.2 to 49.0 µg/L, respectively. High concentrations of lead, cobalt and nickel were identified in all samples of the bottom sediments. The lead content in bottom sediments reaches 11.3, cobalt reaches 10.3–18.0 and nickel reaches 15.0 mg kg−1. The results and their assessment can serve as a basis for future monitoring and measures to reduce pollution, restore the lake ecosystem and ensure the safety of fishery products for humans. © 2024 by the authors.

This study presents the results of an investigation into the effectiveness of microwave (MW) treatment (1) as a preconditioning method for technogenic raw materials (2) to enhance zinc (3) leaching (4) efficiency. Selective dielectric heating facilitates phase transformations (5), converting sphalerite (ZnS) into zinc oxide (ZnO), which exhibits significantly improved acid leachability. The response surface methodology (RSM) was utilized to evaluate critical operational variables, encompassing sulfuric acid concentration, leaching period, slurry density, and thermal conditions. The obtained results confirm the potential of MW treatment in hydrometallurgical processes, offering a sustainable and energy-efficient alternative for processing technogenic raw materials. © 2025 by the authors.

The filament for Fused Deposition Modeling technology was deve-lo ped in a new melt pressure pressing device using metal-polymer composite material. Phase analysis of metal-polymer composite material was carried out by X-ray di fraction. The material was subjected to XRD analysis in the 2θ, 3–90° range, and in Cu Kα radiation at 1.5408 Å and a pitch of 0.02° on a Rigaku MiniFlex. Thermogravimetric analysis was carried out in a Perkin Elmer Pyris instrument at a temperature range of 0 °C – 512.6 °C under a nitrogen atmosphere of 40 mL/min by volume. It was studied at what temperature the heaters in this device should be maintained. In addition, it was found that the metal powders contained in the metal-polymer composite material can be changed to adhesive powders by mechanical compression under a pressure of 18 MPa. The research was carried out under the grant No. AP08857034. © 2022, National Academy of Sciences of the Republic of Kazakhstan. All rights reserved.

Plastic film mulching has long been used in agriculture to enhance productivity, resulting in the substantial input of microplastics derived from plastic film mulching (PFM–MPs) into agricultural soils. However, the impacts of these residues on soil remain unclear. Therefore, in this study, we investigated a 17-year mulched cotton field using integrated physical–chemical–microbiological analyses to explore how PFM–MPs influence the soil structure and microbial communities. The results show that PFM–MP abundance increased significantly with mulching duration (from 683.33 to 9633.33 items/kg) and was predominantly enriched in macroaggregates and mesoaggregates, with soil aggregate stability (mean weight diameter) increasing by approximately 7.8-fold. Multiple lines of analysis identified PFM–MPs as the dominant factor influencing aggregate stability. Furthermore, PFM–MPs enhanced interparticle cohesion by regulating the electrochemical properties of soil particle surfaces, thereby optimizing interparticle interactions and indirectly promoting aggregate stability through the accumulation of hydrophobic plasticizers (e.g., phthalate esters), which increased soil water repellency (contact angle: 9.73° → 23.10°). Amplicon sequencing of 16S rRNA genes revealed pronounced shifts in microbial community composition, characterized by increased relative abundances of Proteobacteria, Gemmatimonadetes, and Acidobacteriota; in addition, the Shannon diversity index increased significantly from 5.69 to 6.72. Finally, partial least squares path modeling clarified that PFM–MPs enhance aggregate stability primarily by modulating soil electrochemical properties and hydrophobicity, thereby altering microbial communities. In summary, there results fills a critical knowledge gap regarding the effects of PFM–MPs on soil aggregates and microbial communities in agricultural soils, thus inform evidence-based policies aimed at managing plastic pollution and ensuring sustainable agriculutural management. © 2025 Elsevier B.V.