Қазақ ұлттық қыздар педагогикалық университеті / Казахский национальный женский педагогический университет
Постоянный URI для этого сообществаhttps://cris.qyzpu.edu.kz/handle/123456789/1
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- Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Physicochemical and Antioxidant Properties of Humic Acids from Low-Sulfur Kazakhstan Shales(Pleiades Publishing, 2022-09-01); ; Индира Мухаметкеримовна ДжелдыбаеваThe structural, chemical, and physicochemical characteristics and antioxidant properties of humic acids isolated from shale in the Kenderlyk and Kiin fields are determined. Negative values of the acids’ oxidation are found: –3.62 and –4.06 for Kenderlyk and Kiin shale, respectively. Thus, the shale-based humic acids are reducing agents. IR spectroscopic data show clear absorption bands of hydroxyl, functional, and carbonyl groups. ESR spectroscopy indicates a high content of paramagnetic centers in the humic acids: 9.3 × 10 17 and 9.5 × 10 17 spin/g for Kenderlyk and Kiin shale, respectively. The paramagnetic centers in the molecular structure of the humic acids indicate that they are promising as antioxidants.Цитирования (OpenAlex) 1Цитирования (OpenCitations) 1 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Physicochemical and Antioxidant Properties of Humic Substances from Coals of the Oy-Karagay and Kiyakty Deposits in the Republic of Kazakhstan(Pleiades Publishing, 2022-12-01); ; S.M. SuimbayevaAbstract The results of studies on the physicochemical and antioxidant properties of humic acids (HAs) and hymatomelanic acids (HMAs) from brown coals of deposits in the Republic of Kazakhstan are presented. It was found that the molecular structure of HAs from coals of the Oy-Karagay and Kiyakty deposits has functional groups of carbonyl, hydroxyl, and aliphatic nature as structural elements. The test samples of coals and HAs were characterized by the occurrence of paramagnetic centers (PMCs) with the Lande spectroscopic splitting factor values above 2.00, which indicate the presence of free radicals caused by a strongly delocalized electron cloud in the molecules of coals and HAs. The results of the amperometric determination of the antioxidant properties of HMAs indicated that the HMAs exhibit antioxidant activity, which will allow them to be used as a biologically active additive in the production of pharmaceutical preparations.Цитирования (OpenAlex) 2Цитирования (OpenCitations) 1