Izvestiya of Saratov University.
Chemistry. Biology. Ecology
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)

Химия

A Comparative Study of Benzene and Toluene Adsorption on KOH-Modified AR-A Activated Carbon: Effect of Concentration and Impregnation Ratio

This study compares the adsorption of benzene and toluene vapors on potassium hydroxide (KOH)-modified AR-A activated carbon (AC), considering their toxicological impact. The primary objective was to evaluate how different KOH concentrations and impregnation ratios influence the adsorption capacity and kinetics for these volatile organic compounds (VOCs). The AC samples were chemically modified using KOH at concentrations of 0.5 M and 1.0 M, using mass-to-volume impregnation ratios of 1:5 and 1:10.

Исследование влияния параметров процесса соосаждения на физико-химические характеристики прекурсора катодного материала NCM811

Подбор параметров синтеза прекурсоров катодных материалов состава NCM является одним из превалирующих факторов, оказывающих существенное влияние на химический состав, насыпную плотность, микроструктуру поверхности, электрохимические характеристики и ресурс получаемых впоследствии катодных материалов. В данной работе исследуется варьирование скорости перемешивания, pH, концентрации комплексообразующего агента, мольное соотношение концентраций NH3/р-р сульфатов.

Синтез и биологическая активность соединений на основе 4-гидроксикумарина

В настоящее время синтез кислородсодержащих гетероциклических соединений, содержащих конденсированную систему бензольного ядра с пироновым циклом, представителем которых является 4-гидроксикумарин (4-гидрокси-2H-хромен-2-он), является очень важным, в связи с их широким спектром биологической активности. Нам представилось интересным проведение реакций 1,5-дикарбонильных соединений на основе 4-гидроксикумарина с N-нуклеофилами, как с фундаментальной точки зрения, так и с позиции практического применения полученных продуктов.

Improving the effi ciency of using sands as artifi cial geochemical barriers

The interaction of sands as artifi cial geochemical barriers with nickel chloride solutions simulating technological effl uents is investigated. The eff ect of pre-acid treatment of sands on their ability to absorb nickel (II) ions is considered experimentally. In experiments, sands with diff erent quartz contents have been studied, in which the only impurity element was aluminum oxide in an amount from 1 to 10% (wt.).

Modified planar sensors for the separate detection of certain cephalosporin antibiotics

Modifi ed screen-printed potentiometric sensors sensitive to cephalosporin antibiotics – cefuroxime (Cefur), cefotaxime (Ceftx), cefazolin (Cef) have been developed. Tetradecylammonium associates with complex compounds silver (I) – cefuroxime (cefotaxime) have been used as electroactive components. The role of magnetic nanoparticles Fe3O4 and cetylpyridinium chloride in improving the electroanalytical properties of sensors in solutions of the studied antibiotics is shown. Optimal ratios of modifi ers in carbon-containing inks (Fe3O4 : CPCh = 1 : 2.5) have been found.

Non-destructive control of tablet forms of cefuroxime by near-infrared spectroscopy and digital colorometry methods

Non-destructive control of cefuroxime in tablet medicines without opening the blister pack by measuring the intensity of diff use refl ectance of infrared radiation has been proposed. Near-infrared Fourier transform spectroscopy and digital color spectroscopy using a smartphone and a 3D-printed device have been applied. The data set has been processed by principal component methods, hierarchical cluster analysis and partial least squares regression.

Oxidative degradation of tetracyclines

Environmental pollution is one of the most pressing problems facing humanity. The constant search for its solution is an important aspect of modern chemistry. The work studied the oxidative degradation of two antibiotics of the same pharmaceutical group, with a similar structure but diff erent properties.

Synthesis of new hybrid molecules based on 7-hydroxy-2,2,4-trimethylhydroquinoline derivatives

Among the fused azaheterocycles, quinolines have long attracted the attention of chemists. First of all, this is due to their wide range of practically useful properties. Quinolines and their derivatives exhibit a wide range of biological activities, including antimalarial, anticancer, antiviral, antifungal and anti-infl ammatory activities. These compounds are also used as fl uorescent probes, luminescent labels, and in dye production.

Quantitative chemical analysis of water in the application of membrane fi ltration

Water pollution poses a danger to human health and, as a result, there is a need to identify ways to clean it. In this study, a quantitative chemical analysis of water taken from the well and after its passage through membrane purifi cation (reverse osmosis method) was carried out in the period from 2019 to 2023. The research area is Moscow, Moskovsky settlement.

Новый вариант реакции Фридлендера в синтезе 7,8-дигидро-6H-фуро[2,3-b]хинолин-5-онов

Гидрированные производные акридина проявляют различные виды биологической активности – известны их антибактериальные, противоопухолевые, противовирусные, психоактивные свойства. На примере гетероаналогов такрина – известного ингибитора холинэстераз, показано, что замена в полициклических системах бензольного кольца на пятичленный гетероцикл приводит к уменьшению токсичности препарата, однако не изменяет базовую физиологическую активность. Таким образом, синтез гетероаналогов известных бензаннелированных систем является актуальной задачей.

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