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Eurasian Chemico-Technological Journal
ISSN
1562-3920
2522-4867
5 результаты
Показано: 1 - 5 из 5
- Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Mechanism of Catalytic Thermal Decomposition of Ammonium Perchlorate in the Presence of Ti3C2Tx(2025-10-17) ;Zhanibek Korkembay ;Moldir Auyelkhankyzy; ;Zulkhair Aimukhametovich MansurovV. BykovThe thermal decomposition of ammonium perchlorate (AP) proceeds via a well-established stepwise mechanism. However, its catalytic decomposition under combustion conditions is not yet fully understood. This study investigates and clarifies the catalytic decomposition pathway of AP in the presence of Ti3C2Tx, a novel two-dimensional (2D) material with unique structural properties. MXene was chosen for its exceptional conductivity, large surface area, and layered architecture, which provide active sites for redox interactions and enhance the thermal decomposition rate of AP. During combustion of AP-based solid rocket propellants, MXene acts as a catalyst, promoting more complete and rapid oxidation reactions. The combustion products were thoroughly analyzed using X-ray phase analysis, and based on the obtained data, stoichiometric equations for the potential reaction pathways were proposed. These equations highlight the formation of metal oxides and intermediate chlorinated compounds. Furthermore, a schematic model illustrating the catalytic action of Ti3C2Tx was developed, showing the interaction between AP molecules and MXene’s surface functional groups. These findings advance understanding of nanocatalyst behavior in energetic materials and offer insights for improving solid-propellant performance via MXene incorporation.Цитирования (OpenAlex) 1 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Acid Modification of Diatomite-Based Sorbents(2020-09-30) ;Araylim Nurgain ;Meruyert Nazhipkyzy ;Aizhan A. Zhaparova ;Almagul IssanbekovaMichela AlfèIn this work, the effect of acid pre-treatment (hydrochloric acid, HCl) and calcination of diatomite, a silicon dioxide-material from natural sources, was studied with the aim to obtain diatomite-based sorbents with specific physicochemical properties. For this, acid pre-treatments with HCl at different calcination conditions, namely HCl concentration (0.5, 1 M) and calcination temperatures (from 600 to 900 °C) were studied. Morphological features different from those of natural diatomite were obtained. It has been found that treatment of diatomite with 0.5 M HCl at 800 °C showed a specific pore volume of 0.008 cm3/g, and a specific surface area of 19.26 m2/g, while the treatment of diatomite with 1.0 M HCl showed a specific pore volume of 0.011cm3/g, and a specific surface area of 25.57 m2/g. The performance of the acid pretreatment of diatomite for adsorption of Pb ions from water was also studied.Цитирования (OpenAlex) 8Цитирования (OpenCitations) 6 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Effect of Cobalt Oxide Content on the Activity of NiO-Co2O3/γ-Al2O3 Catalyst in the Reaction of Dry Reforming of Methane to Synthesis Gas(2020-09-30) ;Laura K. Myltykbayeva ;Gaukhar Yergaziyeva; ;Zinfer R. IsmagilovKusman DossumovThe effect of cobalt oxide content on the activity of NiO-Co2O3/γ-Al2O3 catalyst was investigated in process of dry reforming of methane (DRM) to synthesis gas. It was found that among the studied catalysts the highest activity is shown by the NiO-Co2O3/ γ-Al2O3, where methane conversion is 89%. It was determined by the scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) there are oxides of Ni and Co in the form of nanosized particles on active NiO-Co2O3/γ-Al2O3 catalyst and Co-Ni alloys, formed after the reaction of DRM, the size of 17‒23 nm. Thermogravimetric Analysis (TGA)/ Differential Thermal Analysis (DTA)/ Differential Scanning Calorimetry (DSC) of catalyst showed that the highest weight loss (2.7%) is observed at a degree from 30 to 260 °C after DRM. After heating above 300 °C there is a slight increase in weight, accompanied by an exothermic effect on the DSC curve due to the gas adsorption used to purge the unit. The data indicate the absence of coke formation on NiO-Co2O3/γ-Al2O3 surface. According to TPR-H2 there are peaks at relatively low temperatures of Т1mах = 205 °C and Т2mах = 497 °C on thermally programmed reduction (TPR) TPR-Н2 spectrum of NiO-Со2О3/γ-Al2O3, which are associated with the formation of easily reducible cobalt and nickel oxides, indicating the presence of active and mobile oxygen in the catalyst. These results confirm that the activity of NiO-Co2O3/γ-Al2O3 is due to the formation of nanophases, the presence of active oxygen, and the absence of coke on the catalyst surface.Цитирования (OpenAlex) 7Цитирования (OpenCitations) 6 - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Novel 7-Aryliden-3,3a,4,5,6,7-(hexahydro-5-(2-ethoxyethyl)-2-phenyl- 3-aryl-2H-pyrazolo[4,3-c]pyridine Hydrochloride: Synthesis and Structure(2022-03-31); ;V. К. Yu ;Iskakova Tynyshtyk Kadyrovna; Kayrat M. BeketovA Claisen-Schmidt type reaction of 1-(2-ethoxyethyl)piperidin-4-one with different aromatic aldehydes led to corresponding dienones with a yield of 65‒71%. 7-Arylidene-3,3a,4,5,6,7-(hexahydro-5-(2-ethoxyethyl)-2-phenyl-3-aryl-2H-pyrazolo[4,3-c]pyridines were synthesized by heterocyclization of 3,5-diarylidene-piperidin-4-ones with phenylhydrazine hydrochloride in methanol at 70 °C over 4‒6 h. The X-ray crystal structure determination of 7-(p-methoxybenzyliden)-3,3a,4,5,6,7-(hexahydro-5-(2-ethoxyethyl)-2-phenyl-3-(p-methoxyphenyl)-2H-pyrazolo[4,3-c]pyridine hydrochloride (the deposition number is CCDC 862410) was completed. The piperidine and pyrazoline rings are close to a chair and envelope conformations, respectively. - Некоторые метрики заблокированы вашиминастройками согласия
Тип записи:Публикация, Synthesis of Amidophosphates Based on 1-Ethynyl-1-Aminocyclohexane Upon Microwave Activation and their Biological Activity(2023-03-20); ; ;Nurgali Akylbekov ;Alexey B. DobryninAlexander Romanovich BurilovThe researches for developing the methods for synthesizing new functionally substituted derivatives of alicyclic dialkylamidophosphates, establishing their structure, and searching for promising biologically active compounds in their series, are modern and relevant. The given study aimed to develop the synthesis of amidophosphates based on the example of phosphorylation of 1-ethynyl-1-aminocyclohexane with dialkyl phosphites in the presence of triethylamine in carbon tetrachloride in the Atherton-Todd reaction conditions using microwave irradiation of the reaction mixture. The reaction of 1-ethynyl-1-aminocyclohexane with dialkyl phosphites was carried out in a CCl4 excess at an equimolar ratio of reagents, triethylamine was used as an HCl acceptor. The highest yields of dialkyl- N-(1-ethynylcyclohexan-1-yl)amidophosphates were achieved by adding equimolar amounts of dialkyl phosphites to the mixture of 1-ethynyl-1-aminocyclohexane, triethylamine, and CCl4 followed by the subsequent activation of the mixture in a microwave reactor (MAS-II Plus MW) (MW 102 W, 115 °C, microwave irradiation time was 3‒5 min). The composition and structure of the obtained compounds were proved by elemental analysis, IR, 1H, 13C, 31P NMR spectroscopy, and X-ray diffraction analysis (XRD). The biological tests carried out in laboratory and field conditions allowed identifying diethyl-N-(1-ethynylcyclohexan-1-yl) amidophosphate among the synthesized compounds, which produces a high growth-regulating effect on the growth, development, and yield of agricultural crops.Цитирования (OpenAlex) 2Цитирования (OpenCitations) 1
