Composite zeolite sorbents based on analcime with inclusions of hydrated zirconium dioxide (ZrO2-analcime) have been obtained by hydrothermal treatment of coal fly ash cenospheres with a high glass phase content in the presence of a zirconium compound and an alkaline activating agent at 150 °C and different stirring modes of the reaction mixture. The synthesis products were characterized by XRD, SEM-EDS, STA and low-temperature nitrogen adsorption; their sorption properties with respect to Cs+ and Sr2+ were studied in the pH range of 2–10. It was found that the ZrO2-analcime compositions surpass unmodified analcime by 2–5 times in terms of sorption of Cs+ and Sr2+ and by two orders of magnitude in terms of the distribution coefficient value (KD ~106 ml/g). The process of high-temperature solid-phase transformation of Cs+/Sr2+-exchanged forms of the compositions was studied, which simulates the process of conversion of water-soluble forms of Cs‑137 and Sr‑90 radionuclides into a mineral-like form. It was shown that at 1000 °C the ZrO2-analcime compositions with sorbed Cs+ and Sr2+ undergo the phase transformation resulting in polyphase systems of similar composition based on nepheline, tetragonal ZrO2, and glass phase
{"title":"Sorption Properties of ZrO2-Analcime Composites in Relation to Cs(I) and Sr(II)","authors":"E. Kutikhina, T. Vereshchagina","doi":"10.17516/1998-2836-0258","DOIUrl":"https://doi.org/10.17516/1998-2836-0258","url":null,"abstract":"Composite zeolite sorbents based on analcime with inclusions of hydrated zirconium dioxide (ZrO2-analcime) have been obtained by hydrothermal treatment of coal fly ash cenospheres with a high glass phase content in the presence of a zirconium compound and an alkaline activating agent at 150 °C and different stirring modes of the reaction mixture. The synthesis products were characterized by XRD, SEM-EDS, STA and low-temperature nitrogen adsorption; their sorption properties with respect to Cs+ and Sr2+ were studied in the pH range of 2–10. It was found that the ZrO2-analcime compositions surpass unmodified analcime by 2–5 times in terms of sorption of Cs+ and Sr2+ and by two orders of magnitude in terms of the distribution coefficient value (KD ~106 ml/g). The process of high-temperature solid-phase transformation of Cs+/Sr2+-exchanged forms of the compositions was studied, which simulates the process of conversion of water-soluble forms of Cs‑137 and Sr‑90 radionuclides into a mineral-like form. It was shown that at 1000 °C the ZrO2-analcime compositions with sorbed Cs+ and Sr2+ undergo the phase transformation resulting in polyphase systems of similar composition based on nepheline, tetragonal ZrO2, and glass phase","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"14 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78786971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper reports on an effective method for depolymerization of fucoidan in an aqueous medium using ultrasonic treatment. To assess the effect of this treatment, high-molecular-weight fucoidan was dispersed at a concentration of 10 mg/ml in deionized water and subjected to ultrasound at a frequency of 20 kHz with varying intensity. The effect of high-intensity low-frequency ultrasound on the particle size of sulfated polysaccharides isolated from brown algae, where the minimum value of the average hydrodynamic diameter was 85.92 ± 32.9 nm, was studied. The dependence of the particle size of the polysaccharide on the intensity of ultrasonic exposure was revealed. The influence of this effect on the degree of sulfation of fucoidan has been determined. Shown the cavitation activity in the processing environment and discussed the reasons for its change
{"title":"High-Intensity Low-Frequency Ultrasonic Treatment of Sulfated Polysaccharide from Brown Algae","authors":"V. E. Suprunchuk","doi":"10.17516/1998-2836-0265","DOIUrl":"https://doi.org/10.17516/1998-2836-0265","url":null,"abstract":"This paper reports on an effective method for depolymerization of fucoidan in an aqueous medium using ultrasonic treatment. To assess the effect of this treatment, high-molecular-weight fucoidan was dispersed at a concentration of 10 mg/ml in deionized water and subjected to ultrasound at a frequency of 20 kHz with varying intensity. The effect of high-intensity low-frequency ultrasound on the particle size of sulfated polysaccharides isolated from brown algae, where the minimum value of the average hydrodynamic diameter was 85.92 ± 32.9 nm, was studied. The dependence of the particle size of the polysaccharide on the intensity of ultrasonic exposure was revealed. The influence of this effect on the degree of sulfation of fucoidan has been determined. Shown the cavitation activity in the processing environment and discussed the reasons for its change","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"74 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89838364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. V. Burmakina, Dmitry V. Zimonin, V. V. Verpekin, A. I. Rubaylo
The reduction of levulinic acid by electrochemical methods in acetonitrile with or without proton donor on platinum, rhodium, glassy carbon, dropping mercury, iron, copper and lead electrodes were studied. The reduction of levulinic acid was shown to depend on the nature of electrode material and to proceed according to either electrocatalytic or electrochemical mechanisms
{"title":"Electrochemical Study of the Reduction of Levulinic Acid in Acetonitrile on Various Electrodes","authors":"G. V. Burmakina, Dmitry V. Zimonin, V. V. Verpekin, A. I. Rubaylo","doi":"10.17516/1998-2836-0262","DOIUrl":"https://doi.org/10.17516/1998-2836-0262","url":null,"abstract":"The reduction of levulinic acid by electrochemical methods in acetonitrile with or without proton donor on platinum, rhodium, glassy carbon, dropping mercury, iron, copper and lead electrodes were studied. The reduction of levulinic acid was shown to depend on the nature of electrode material and to proceed according to either electrocatalytic or electrochemical mechanisms","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"74 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87263298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reduction of para-nitrosopyridylphenols with hydrazine hydrate in ethanol made it possible to obtain previously unavailable per-substituted para-aminophenols with pyridine substituents. The structure of the compounds obtained for the first time was confirmed by IR, 1H NMR spectroscopy and mass spectrometry
{"title":"Reducing of Sterically Hindered Pyridine Substituted Para-Nitrosophenols","authors":"Alexey A. Kukushkin","doi":"10.17516/1998-2836-0245","DOIUrl":"https://doi.org/10.17516/1998-2836-0245","url":null,"abstract":"Reduction of para-nitrosopyridylphenols with hydrazine hydrate in ethanol made it possible to obtain previously unavailable per-substituted para-aminophenols with pyridine substituents. The structure of the compounds obtained for the first time was confirmed by IR, 1H NMR spectroscopy and mass spectrometry","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74862366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Parshin, E. A. Serov, D. Sobolev, T. Krapivnitskaia, S. A. Bulanova, A. Vakhin, N. Peskov, M. Glyavin
For the sub-THz range, a method for studying the electrodynamic characteristics of organic materials – caustobiolithes-is developed on the basis of a resonator spectrometer. In the frequency range 110 ÷ 260 GHz, the dielectric parameters (refractive index n and tanδ) of peat powders after its microwave processing in the process of «soft» pyrolysis, as well as core sections of oil-containing rock, were studied. The influence of natural humidity on the dielectric parameters of the samples is considered. The reasons for the spread of measurement results, which is observed in these materials and is their specific feature, are discussed
{"title":"Resonator Method for Studying Dielectric Characteristics of Сaustobiolithes","authors":"V. Parshin, E. A. Serov, D. Sobolev, T. Krapivnitskaia, S. A. Bulanova, A. Vakhin, N. Peskov, M. Glyavin","doi":"10.17516/1998-2836-0239","DOIUrl":"https://doi.org/10.17516/1998-2836-0239","url":null,"abstract":"For the sub-THz range, a method for studying the electrodynamic characteristics of organic materials – caustobiolithes-is developed on the basis of a resonator spectrometer. In the frequency range 110 ÷ 260 GHz, the dielectric parameters (refractive index n and tanδ) of peat powders after its microwave processing in the process of «soft» pyrolysis, as well as core sections of oil-containing rock, were studied. The influence of natural humidity on the dielectric parameters of the samples is considered. The reasons for the spread of measurement results, which is observed in these materials and is their specific feature, are discussed","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"289 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74772406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The redox properties of levulinic acid (LA) were studied by electrochemical methods in acetonitrile, a mixture of acetonitrile with water, ethanol, acetone, and dimethyl sulfoxide. It was shown that the irreversible two-electron reduction of LA under the studied conditions leads to the formation of γ-valerolactone. This reduction potential depends on the solvent and shifted anodically by following order: dimethyl sulfoxide
{"title":"Electrochemical Study of the Redox Properties of Levulinic Acid in Organic and Aqueous-Organic Solutions","authors":"G. V. Burmakina","doi":"10.17516/1998-2836-0246","DOIUrl":"https://doi.org/10.17516/1998-2836-0246","url":null,"abstract":"The redox properties of levulinic acid (LA) were studied by electrochemical methods in acetonitrile, a mixture of acetonitrile with water, ethanol, acetone, and dimethyl sulfoxide. It was shown that the irreversible two-electron reduction of LA under the studied conditions leads to the formation of γ-valerolactone. This reduction potential depends on the solvent and shifted anodically by following order: dimethyl sulfoxide","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"97 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88311061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Novikova, Darya I. Tsyplenkova, A. Kuzubov, O. Kolenchukova, A. Samoilo, S. Vorobyev
The calcium complex of ceftriaxone was synthesized and characterized by elemental, atomic-emission analysis, TGA, IR spectroscopy and density functional theory calculations. The luminescence and antibacterial properties of the ceftriaxone disodium and calcium complex were investigated. Ca(II) complex was obtained in a crystalline form, cell parameters of the compound were determined. Ceftriaxone was coordinated to the calcium ion by the oxygen of the triazine cycle in the 6th position, the nitrogen of the amine group of the thiazole ring, and the oxygens of the lactam carbonyl and carboxylate groups. The complex of Ca(II) with ceftriaxone was screened for antibacterial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, and the results were compared with the activity of ceftriaxone disodium salt
{"title":"Complex of Ca(II) with Ceftriaxone: Synthesis, Structure, Spectral and Antibacterial Properties","authors":"G. Novikova, Darya I. Tsyplenkova, A. Kuzubov, O. Kolenchukova, A. Samoilo, S. Vorobyev","doi":"10.17516/1998-2836-0238","DOIUrl":"https://doi.org/10.17516/1998-2836-0238","url":null,"abstract":"The calcium complex of ceftriaxone was synthesized and characterized by elemental, atomic-emission analysis, TGA, IR spectroscopy and density functional theory calculations. The luminescence and antibacterial properties of the ceftriaxone disodium and calcium complex were investigated. Ca(II) complex was obtained in a crystalline form, cell parameters of the compound were determined. Ceftriaxone was coordinated to the calcium ion by the oxygen of the triazine cycle in the 6th position, the nitrogen of the amine group of the thiazole ring, and the oxygens of the lactam carbonyl and carboxylate groups. The complex of Ca(II) with ceftriaxone was screened for antibacterial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, and the results were compared with the activity of ceftriaxone disodium salt","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"11 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85249862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nanostructured titanium dioxide films were prepared by electrochemical oxidation technique, anodization voltage effect on structure morphology, optical and photoelectrocatalytic performances of the nanotubes were studied. The anodization voltage is shown to significantly affect structure of nanofilms and, accordingly, their photoelectrocatalytic activity. An active heterojunction photoanode was synthesised with electrodeposition of Cu₂O onanodized TiO₂. The anode photoelectroact ivityunder bias 1V (Ag/AgCl/3,5M KCl) is found to be 15 % higher than that of the original nanostructured TiO₂ film
{"title":"Synthesis and Photoelectrocatalytic Activity of Anodic Nanostructured TiO₂ Films","authors":"N. A. Zos'ko","doi":"10.17516/1998-2836-0249","DOIUrl":"https://doi.org/10.17516/1998-2836-0249","url":null,"abstract":"Nanostructured titanium dioxide films were prepared by electrochemical oxidation technique, anodization voltage effect on structure morphology, optical and photoelectrocatalytic performances of the nanotubes were studied. The anodization voltage is shown to significantly affect structure of nanofilms and, accordingly, their photoelectrocatalytic activity. An active heterojunction photoanode was synthesised with electrodeposition of Cu₂O onanodized TiO₂. The anode photoelectroact ivityunder bias 1V (Ag/AgCl/3,5M KCl) is found to be 15 % higher than that of the original nanostructured TiO₂ film","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"46 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88164808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kinetics of synthesis of epoxy-amine oligomers that are used as polielectrolytes in technology of cathodic electrodeposition was researched. Solubilityof the reaction product was researched by a correlation between pH and amount of neutralizing agent, molar mass distribution was researched for confirmation of expected molar mass. Pigment paste in three different options was made and used in a mixture with binder emulsion to receive coatings deposited on a cathode. Their properties were researched
{"title":"Synthesis of Water-Solved Epoxy-Amine Oligomers and Receiving Coating Based on Them by Cathodic Electrodeposition","authors":"Yu. V. Churilov","doi":"10.17516/1998-2836-0244","DOIUrl":"https://doi.org/10.17516/1998-2836-0244","url":null,"abstract":"Kinetics of synthesis of epoxy-amine oligomers that are used as polielectrolytes in technology of cathodic electrodeposition was researched. Solubilityof the reaction product was researched by a correlation between pH and amount of neutralizing agent, molar mass distribution was researched for confirmation of expected molar mass. Pigment paste in three different options was made and used in a mixture with binder emulsion to receive coatings deposited on a cathode. Their properties were researched","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"11 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78399380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study of the carbon isotopic composition in organic-bearing bottom sediments of the thermal lake Fumarolnoye (Uzon caldera, Kamchatka) has been carried out. The results of studying δ13C changes in the bottom sediments of a thermal lake during the sequential extraction of H3PO4 for 2 hours, 24 hours and 7 days are presented. The change in δ13С with time and after treatment with HCl and H2O2 is shown using two samples as an example. After treatment with HCl, the δ13С values change relative to the initial ones from 1 to 3 ‰, which can be taken into account when interpreting the data. The standard procedure for removing carbonate with hydrogen peroxide reveals a significant transformation of the residual C‑containing substance in the case of a prolonged reaction with H3PO4 at elevated temperatures
{"title":"Specific of Stable Carbon Isotopes Determination in Organic-Bearing Sediments","authors":"E. Lazareva","doi":"10.17516/1998-2836-0251","DOIUrl":"https://doi.org/10.17516/1998-2836-0251","url":null,"abstract":"The study of the carbon isotopic composition in organic-bearing bottom sediments of the thermal lake Fumarolnoye (Uzon caldera, Kamchatka) has been carried out. The results of studying δ13C changes in the bottom sediments of a thermal lake during the sequential extraction of H3PO4 for 2 hours, 24 hours and 7 days are presented. The change in δ13С with time and after treatment with HCl and H2O2 is shown using two samples as an example. After treatment with HCl, the δ13С values change relative to the initial ones from 1 to 3 ‰, which can be taken into account when interpreting the data. The standard procedure for removing carbonate with hydrogen peroxide reveals a significant transformation of the residual C‑containing substance in the case of a prolonged reaction with H3PO4 at elevated temperatures","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"2 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87719448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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