В данной работе простым гидротермальным методом синтезированы три типа структур кобальтита цинка ZnCo2O4 на никелевой пене: наностержни, нанонити и пластины. Исследованы морфология и структурные характеристики синтезированных образцов. Выращенные структуры могут быть использованы в качестве основы для бесферментных электрохимических биосенсоров. Методом сканирующей электронной микроскопии (SEM) был проведен детальный анализ серии из шести образцов, синтезированных при различных соотношениях Zn:Co (1:1, 1:10 и 10:1). Результаты исследования элементного состава наноструктур ZnCo₂O₄, синтезированных гидротермальным методом на никелевой пене, показали, что состав полученных материалов коррелирует с составом исходного ростового раствора, подтверждая контролируемость процесса легирования. Отсутствие каких-либо примесей свидетельствует о высокой чистоте синтезированных образцов. Полученные данные подтверждают возможность точного управления стехиометрией кобальтита цинка. Показано, что морфология выращенных образцов зависит от стехиометрии прекурсоров, обеспечивая управляемый рост наноструктурированных материалов. Показано, что гидротермальный метод синтеза наноструктур ZnCo₂O₄ позволяет получать материалы с широким диапазоном стехиометрии от кобальт- до цинксодержащих фаз, что открывает возможности для тонкой настройки эффективных, функциональных свойств ZnCo₂O₄.

Полупроводниковые наноструктурированные образцы ZnOи ZnO-GOбыли получены при комнатной температуре методом химического осаждения из раствора.В работе исследовано электрохимическое неферментативное определение аскорбиновой кислоты с помощью полученных наноструктур, нанесённых на стеклоуглеродный электрод. Морфология и структурные свойства изготовленных наноструктурированных материалов были проанализированы с помощью электронного растровогомикроскопа и рентгеновскогодифрактометра. Электрохимические свойствабыли исследованыметодами циклической вольтамперометрии на одноканальном потенциостате-гальваностате. Чувствительность полученных электродовбыла рассчитана для концентрацийаскорбиновой кислотыв фосфатно-буферном растворе от 0,3мМ до 3 мМ при различных скоростях сканирования. Таким образом,было выявлено, что чувствительность образца ZnO-GO ниже, чем у образцаZnO, что может быть связано с диэлектрическими свойствами оксида графена. Однако после отжига в атмосфере чувствительность образца ZnO-GO повысилась, что связано суменьшением дефектов в образце и увеличениемудельной поверхности образцов. В результате исследованийбыл получен модифицированный ZnO-GO/GCE электрод с высокой чувствительностью 386 мкАМ-1см-2,перспективный для использования в качестве основы биосенсора для определения уровнявитамина C вкрови,пищевых продуктах и лекарствах.

An overview of the composition of wolframite ores of the Akchatau deposit and the technologies for processing concentrates using NaOH and Na2CO3 by hydro- and pyrometallurgical methods is given, and the disadvantages associated with both the technology and the equipment are noted. To develop a technology for processing Akchatau wolframite concentrates, samples of ore materials were taken, the chemical and mineralogical composition of the samples was studied, and enrichment was carried out to obtain rich concentrates. The kinetics of the sintering of the wolframite concentrate with soda was investigated, the dependences of the degree of transformation of the tungsten minerals into sodium tungstate were obtained, and the rate constants, the order of the reaction, and the values of the apparent activation energy were calculated. The results of sintering an enlarged sample of wolframite concentrate with soda in a muffle furnace are presented. After the subsequent leaching, studies were carried out to purify the obtained solutions of sodium tungstate from the impurities while eliminating the operations of the neutralizing solutions through the use of electrodialysis with an MK-40 cation-exchange membrane. The scheme of processing the wolframite ores of Akchatau is proposed.

This review highlights advancements in ethylene removal technologies tailored for fruit and vegetable (F&V) preservation, with a focus on physical adsorption and chemical elimination methods. Conventional approaches, such as potassium permanganate (KMnO₄) and 1-methylcyclopropene (1-MCP), are limited by toxicity concerns, declining efficiency, and potential fruit disorders. Emerging alternatives, particularly catalytic oxidation using metal oxide catalysts like TiO₂, offer efficient ethylene degradation into non-toxic byproducts. Incorporating these catalysts with porous materials, such as zeolites, enhances ethylene adsorption while providing multifunctional benefits, including antibacterial activity. In addition to discussing the materials of the adsorbents, their binding mechanisms (such as van der Waals forces and π-complexation) were also studied. Future research directions include improving cost-efficiency, optimizing material performance for practical applications, and ensuring food safety in packaging systems. These advancements represent a sustainable strategy to extend the shelf life of F&V in the postharvest supply chain. © 2025

Large volume changes, the insulating nature of sulfur, and the lithium polysulfides (LiPSs) shuttle effect significantly hinder the practical application of lithium-sulfur (Li-S) batteries. In this study, reduced graphene oxide/MXene (rGO/MXene) composites were investigated as potential sulfur host materials. Since the rGO-to-MXene ratio influences electrical conductivity, LiPSs confinement, and structural stability, MXene contents of 10 wt%, 20 wt%, and 30 wt% were systematically evaluated. The (rGO/MXene10)_S60 electrode exhibited the most promising performance, delivering an initial discharge capacity of 981 mAh/g and retaining 606 mAh/g after 100 cycles with Coulombic efficiency (CE) above 97 %. These results demonstrate that a 9:1 rGO-to-MXene ratio optimally enhances conductivity, structural stability, and LiPSs anchoring, making it a promising sulfur host for Li-S batteries.

At present, when the whole world is intensively switching to organic farming, the refusal or minimization of the usage of chemical plant protection products and synthesized fertilizers is a very urgent issue for the agro-industrial complex (AIC). Accordingly, the solution to the problems of increasing yields and ensuring the fight against pathogenic components should be carried out in accordance with the principles of “green” chemistry. In this regard, the usage of heteroleptic complexes based on carboxylic and amino acids with biogenic metals is dictated not only by their availability, low cost, and ability to increase crop yields but also by fungicidal activity, lower toxicity, and easy biodegradability, which lists them among the “green” and cost-effective plant biostimulants. In the present work, for the first time, a heteroleptic complex based on succinic acid and glycine, with the formula [Cu(succ)(gly)], was developed for usage as a fungicidal biostimulant, which has the ability to significantly reduce the number of pathogens. We found that this compound has a layered structure and was able to increase soybean germination up to 100%. © 2023 by the authors.

One of the most interesting and poorly studied carriers of medicinal substances is the polymer clay composite material (PCCM). Bentonite clays are used in pharmacy for the manufacturing of various dosage forms, as well as in the adsorption of drugs to slow their release. Polymer–clay nanocomposites have demonstrated significantly improved properties compared to pure polymers. A review of recent scientific advances has shown promising results regarding the application of polymer–clay materials in medicine and bioengineering, particularly in the development of carrier sorbents with prolonged action for controlled drug release. As a result, interest in polymer–clay systems is steadily growing and gaining momentum. This paper focuses on the structure and properties of bentonite clays, including their sorption, ion exchange, binding, and rheological properties. The methods for preparing intercalated and exfoliated nanocomposites, such as radical intercalative polymerization in situ on clay surfaces, are reviewed. Furthermore, the improved efficacy and exposure times of PCCMs, combined with their enhanced bactericidal properties, are analyzed for the creation of universal and multifunctional preparations for medical use. © 2025 by the authors.

Providing safe drinking water to people in developing countries is an urgent worldwide water problem and a main issue in the UN Sustainable Development Goals. One of the most efficient and cheapest methods to attain these goals is to promote the use of slow sand filters. This review shows that slow sand filters can efficiently provide safe drinking water to people living in rural communities not served by a central water supply. Probably, the most important aspect of SSF for developing and less-developed countries is its function as a biological filter. WASH problems mainly relate to the spread of viruses, bacteria, and parasites. The surface and shallow groundwater in developing countries around urban areas and settlements are often polluted by domestic wastewater containing these microbes and nutrients. Thus, SSF’s function is to treat raw water in the form of diluted wastewater where high temperature and access to nutrients probably mean a high growth rate of microbes and algae but probably also high predation and high efficiency of the SSF. However, factors that may adversely affect the removal of microbiological constituents are mainly low temperature, high and intermittent flow rates, reduced sand depth, filter immaturity, and various filter amendments. Further research is thus needed in these areas, specifically for developing countries. © 2023 by the authors.