Pub Date : 2023-03-05DOI: 10.29235/1561-8331-2023-59-1-26-34
Z. Kuvaeva, S. P. Kacherskaya, O. S. Mastitskaya, E. A. Khvalova
A simple, fast, sensitive method for the determination of preservatives (methyl parahydroxybenzoate, propyl parahydroxybenzoate) in the finished dosage form of sodium oxybutyrate syrup based on the simultaneous determination of preservatives using high performance liquid chromatography (HPLC) is proposed. The HPLC method was validated. The correlation coefficient of the linearity of the technique was 0.999 in the application range of 80–120 % of the normalized value. The calibration graph is linear in the region of 0.495–0.990 mg/ml of methyl 4-hydroxybenzoate and 0.165–0.330 mg/ml of propyl 4-hydroxybenzoate. It has been established that the analytical characteristics of the test procedure (selectivity, linearity, correctness, repeatability, reproducibility) satisfy the selected acceptance criteria.
{"title":"Development and validation of the method for quantitative determination of preservatives in sodium oxybutyrate syrup","authors":"Z. Kuvaeva, S. P. Kacherskaya, O. S. Mastitskaya, E. A. Khvalova","doi":"10.29235/1561-8331-2023-59-1-26-34","DOIUrl":"https://doi.org/10.29235/1561-8331-2023-59-1-26-34","url":null,"abstract":"A simple, fast, sensitive method for the determination of preservatives (methyl parahydroxybenzoate, propyl parahydroxybenzoate) in the finished dosage form of sodium oxybutyrate syrup based on the simultaneous determination of preservatives using high performance liquid chromatography (HPLC) is proposed. The HPLC method was validated. The correlation coefficient of the linearity of the technique was 0.999 in the application range of 80–120 % of the normalized value. The calibration graph is linear in the region of 0.495–0.990 mg/ml of methyl 4-hydroxybenzoate and 0.165–0.330 mg/ml of propyl 4-hydroxybenzoate. It has been established that the analytical characteristics of the test procedure (selectivity, linearity, correctness, repeatability, reproducibility) satisfy the selected acceptance criteria.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81944012","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-423-432
S. Kakareka, T. Kukharchyk
The results of the first assessment of the antimony release into the atmospheric air on the territory of Belarus are discussed. The main anthropogenic sources of antimony emission have been identified, the emission factors have been developed, and the volumes of antimony emission for the period from 1990 to 2020 have been calculated. It is shown that total antimony emissions varied in the range from 1.6 to 5.6 tons per year with maximum values in the early 1990 s, and minimal – in 2000. Antimony emission in 2020 on the territory of the country is estimated at 2.4 t, the contribution of Belarus to global emission is 0.1 %. Decreasing trend of antimony emission over a 30-year period and a change in the contribution of the main sources to total emission have been established. A significant decrease in the contribution of stationary combustion of fuel (from 66 to 14 %) is due to a change in the fuel balance and is accompanied by increase of the contribution of brake wear (from 34 to 61 %). The data obtained can be used to model the transport and dispersion of antimony, to assess health and ecosystems risks, and to develope measures to reduce the releases of antimony into the environment.
{"title":"The release of antimony into the atmospheric air on the territory of Belarus: sources, levels and long-term dynamics","authors":"S. Kakareka, T. Kukharchyk","doi":"10.29235/1561-8331-2022-58-4-423-432","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-423-432","url":null,"abstract":"The results of the first assessment of the antimony release into the atmospheric air on the territory of Belarus are discussed. The main anthropogenic sources of antimony emission have been identified, the emission factors have been developed, and the volumes of antimony emission for the period from 1990 to 2020 have been calculated. It is shown that total antimony emissions varied in the range from 1.6 to 5.6 tons per year with maximum values in the early 1990 s, and minimal – in 2000. Antimony emission in 2020 on the territory of the country is estimated at 2.4 t, the contribution of Belarus to global emission is 0.1 %. Decreasing trend of antimony emission over a 30-year period and a change in the contribution of the main sources to total emission have been established. A significant decrease in the contribution of stationary combustion of fuel (from 66 to 14 %) is due to a change in the fuel balance and is accompanied by increase of the contribution of brake wear (from 34 to 61 %). The data obtained can be used to model the transport and dispersion of antimony, to assess health and ecosystems risks, and to develope measures to reduce the releases of antimony into the environment.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89535877","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-369-378
E. Dikusar, A. Pushkarchuk, T. V. Bezyazychnaya, E. A. Akishina, A. Soldatov, S. Kuten, S. Stepin, A. Nizovtsev, S. Kilin, V. Kulchitsky, V. Potkin
In order to therapeutically destroy neoplasms, chemotherapy or radiotherapy is usually applied, and in isotope medicine short-lived radionuclides are injected into the tumor (59Fe, 90Y, 95Zr, 99mTc, 106Ru, 114*In, 147Eu, 148Eu, 155Eu, 170Tm, 177mLu, 188Re, 210Po, 222Rn, 230U, 237Pu, 240Cm, 241Cm, 253Es). Binary (or neutron capture) therapy is a technology designed to selectively treat malignant tumors and using drugs tropic to tumors containing non-radioactive nuclides (10B, 113Cd, 157Gd at al.). Triadic therapy is the sequential introduction into the body of a combination of two or more separately inactive and harmless components, tropic to tumor tissues and capable of selectively accumulating in them or entering into chemical interaction with each other and destroying tumor neoplasms under certain sensitizing external influences. The aim of this work is to quantum-chemically simulate the electronic structure and to analyze the thermodynamic stability of new doxorubicino-fullerenol agents for the treatment of tumor neoplasms. The need for preliminary studies on the modeling of such objects is due to the extremely high labor intensity, cost and complexity of their practical production.
{"title":"Quantum-chemical modeling of doxorubicino-fullerenol agents of cancer therapy","authors":"E. Dikusar, A. Pushkarchuk, T. V. Bezyazychnaya, E. A. Akishina, A. Soldatov, S. Kuten, S. Stepin, A. Nizovtsev, S. Kilin, V. Kulchitsky, V. Potkin","doi":"10.29235/1561-8331-2022-58-4-369-378","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-369-378","url":null,"abstract":"In order to therapeutically destroy neoplasms, chemotherapy or radiotherapy is usually applied, and in isotope medicine short-lived radionuclides are injected into the tumor (59Fe, 90Y, 95Zr, 99mTc, 106Ru, 114*In, 147Eu, 148Eu, 155Eu, 170Tm, 177mLu, 188Re, 210Po, 222Rn, 230U, 237Pu, 240Cm, 241Cm, 253Es). Binary (or neutron capture) therapy is a technology designed to selectively treat malignant tumors and using drugs tropic to tumors containing non-radioactive nuclides (10B, 113Cd, 157Gd at al.). Triadic therapy is the sequential introduction into the body of a combination of two or more separately inactive and harmless components, tropic to tumor tissues and capable of selectively accumulating in them or entering into chemical interaction with each other and destroying tumor neoplasms under certain sensitizing external influences. The aim of this work is to quantum-chemically simulate the electronic structure and to analyze the thermodynamic stability of new doxorubicino-fullerenol agents for the treatment of tumor neoplasms. The need for preliminary studies on the modeling of such objects is due to the extremely high labor intensity, cost and complexity of their practical production.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85537583","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-379-386
B. Ranishenka, I. Chelnokova, A. Poznyak
Aluminium and mica (muscovite) plates have been functionalized with azide groups by a protocol which includes (3-chloropropyl) trichlorosilane modification followed by chlorine atom nucleophilic substitution by azide. The azide groups have been transformed to dimethoxytrityl (DMT) ones by [3+2] azide-alkyne cycloaddition reaction. This made it possible to determine their number per surface unit photometrically, based on the absorption of the DMT cation. The functionalization method allowed to achieve high surface load of the materials by azide groups, which was 2.2 and 2.7 nm-2 for mica and aluminium, respectively. The mica plates have been additionally functionalized by 25 kDa branched polyethylenimine. The samples have shown a capability for adsorptive nanoand microobjects immobilization. The feature could be useful for atomic force microscopy, which have been demonstrated with erythrocytes and exosomes.
{"title":"Aluminium and mica azide surface functionalization","authors":"B. Ranishenka, I. Chelnokova, A. Poznyak","doi":"10.29235/1561-8331-2022-58-4-379-386","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-379-386","url":null,"abstract":"Aluminium and mica (muscovite) plates have been functionalized with azide groups by a protocol which includes (3-chloropropyl) trichlorosilane modification followed by chlorine atom nucleophilic substitution by azide. The azide groups have been transformed to dimethoxytrityl (DMT) ones by [3+2] azide-alkyne cycloaddition reaction. This made it possible to determine their number per surface unit photometrically, based on the absorption of the DMT cation. The functionalization method allowed to achieve high surface load of the materials by azide groups, which was 2.2 and 2.7 nm-2 for mica and aluminium, respectively. The mica plates have been additionally functionalized by 25 kDa branched polyethylenimine. The samples have shown a capability for adsorptive nanoand microobjects immobilization. The feature could be useful for atomic force microscopy, which have been demonstrated with erythrocytes and exosomes.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83541861","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-387-397
A. G. Polonevich, S. Leschev, V. A. Bulhakava, L. L. Belyshava
Method for determination of the insecticide amitraz residual content in honey has been developed and validated. The method is selective, express and easy-to-perform. The technique is based on the extraction of amitraz from alkalized aqueous solutions of honey with n-hexane and quantitative determination by high-performance liquid chromatography with mass spectrometric detection. Validation was performed using three types of honey at three levels of amitraz application 6, 120 and 220 µg/kg. The limit of quantification was 0.9 µg/kg, the calibration curves were linear in the concentration range from 2.5 to 125.0 ng/mL (the corresponding analyte content in honey is from 5.0 to 250.0 µg/kg), relative values of the standard deviations of repeatability and within-laboratory reproducibility did not exceed 3.4 and 5.9 %, respectively, the bias values varied from –8.2 to 5.6 %, the expanded uncertainty estimates of the results ranged from 12 to 16 % (P = 0.95). Instrumental limit of quantification, overall efficiency of the process and robustness were also evaluated during the validation process.
建立了测定蜂蜜中杀虫剂阿米特唑残留量的方法，并进行了验证。该方法具有选择性强、快速、简便等特点。本技术以正己烷萃取蜂蜜碱化水溶液中的阿米特拉兹为基础，采用高效液相色谱-质谱法进行定量测定。使用三种蜂蜜在阿米特拉兹的三种水平(6、120和220µg/kg)下进行验证。量化的极限是0.9µg /公斤,校准曲线的线性浓度范围从2.5到125.0 ng / mL(相应的蜂蜜是分析物含量从5.0到250.0µg / kg),重复性和相对标准差的值within-laboratory重现性不超过5.9%和3.4,分别偏差值变化从-8.2到5.6%,结果的扩展不确定度的估计范围从12至16% (P = 0.95)。在验证过程中还评估了定量的仪器极限，过程的总体效率和稳健性。
{"title":"Development and validation of the method for determination of amitraz in honey using high-performance liquid chromatography with mass spectrometric detection","authors":"A. G. Polonevich, S. Leschev, V. A. Bulhakava, L. L. Belyshava","doi":"10.29235/1561-8331-2022-58-4-387-397","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-387-397","url":null,"abstract":"Method for determination of the insecticide amitraz residual content in honey has been developed and validated. The method is selective, express and easy-to-perform. The technique is based on the extraction of amitraz from alkalized aqueous solutions of honey with n-hexane and quantitative determination by high-performance liquid chromatography with mass spectrometric detection. Validation was performed using three types of honey at three levels of amitraz application 6, 120 and 220 µg/kg. The limit of quantification was 0.9 µg/kg, the calibration curves were linear in the concentration range from 2.5 to 125.0 ng/mL (the corresponding analyte content in honey is from 5.0 to 250.0 µg/kg), relative values of the standard deviations of repeatability and within-laboratory reproducibility did not exceed 3.4 and 5.9 %, respectively, the bias values varied from –8.2 to 5.6 %, the expanded uncertainty estimates of the results ranged from 12 to 16 % (P = 0.95). Instrumental limit of quantification, overall efficiency of the process and robustness were also evaluated during the validation process.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74313876","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-398-406
E. Ulashchik, T. P. Akhlamionok, P. Y. Baryshchyk, O. Sharko, V. Shmanai
A synthetic protocol was developed and optimal reagents have been selected for obtaining guide RNA oligonucleotides for the CRISPR/Cas system using ASM-2000 automatic synthesizer in 500 nmol scale. Methods for the isolation, purification and analytical control of synthetic RNA oligonucleotides have been developed. The improved technology has been used for preparation of guide RNAs for the CRISPR Cas12a system.
{"title":"Optimization of the technology for obtaining guide RNA using plate automatic synthesizer","authors":"E. Ulashchik, T. P. Akhlamionok, P. Y. Baryshchyk, O. Sharko, V. Shmanai","doi":"10.29235/1561-8331-2022-58-4-398-406","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-398-406","url":null,"abstract":"A synthetic protocol was developed and optimal reagents have been selected for obtaining guide RNA oligonucleotides for the CRISPR/Cas system using ASM-2000 automatic synthesizer in 500 nmol scale. Methods for the isolation, purification and analytical control of synthetic RNA oligonucleotides have been developed. The improved technology has been used for preparation of guide RNAs for the CRISPR Cas12a system.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85291631","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-418-422
U. Eshbaeva, A. Djalilov
In the modern world, the importance and volumes of packaging produced are constantly increasing. It is a powerful means of promoting goods on the market, but at the same time, the role of its quality increases. Currently, paper and paperboard packaging is not only a significant part of paper and paperboard market in general, but also a large part of the world’s packaging consumption. Currently, the world pays special attention to the use of secondary paper waste for the production of paper and cardboard and increase the volume of their processing. The article is devoted to the production of new types of multilayer paper and cardboard with the addition of chemical fiber and secondary waste, as well as high-quality paper and cardboard that can be used in the printing industry, in order to save valuable cotton cellulose in the country. However, the article shows in what proportions it is advisable to use secondary fibers in combination with cellulose in the production of multilayer composite paper and cardboard for the printing and paper industries.
{"title":"Composite technology for the production of paper and cardboard including synthetic fibers","authors":"U. Eshbaeva, A. Djalilov","doi":"10.29235/1561-8331-2022-58-4-418-422","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-418-422","url":null,"abstract":"In the modern world, the importance and volumes of packaging produced are constantly increasing. It is a powerful means of promoting goods on the market, but at the same time, the role of its quality increases. Currently, paper and paperboard packaging is not only a significant part of paper and paperboard market in general, but also a large part of the world’s packaging consumption. Currently, the world pays special attention to the use of secondary paper waste for the production of paper and cardboard and increase the volume of their processing. The article is devoted to the production of new types of multilayer paper and cardboard with the addition of chemical fiber and secondary waste, as well as high-quality paper and cardboard that can be used in the printing industry, in order to save valuable cotton cellulose in the country. However, the article shows in what proportions it is advisable to use secondary fibers in combination with cellulose in the production of multilayer composite paper and cardboard for the printing and paper industries.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90633411","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}
Pub Date : 2022-11-29DOI: 10.29235/1561-8331-2022-58-4-407-417
V. Fleisher
Resin acid amides of rosin, depending on the structure, can have both a hydrophobizing and hardening effect on paper pulps. It has been established that the developed products of rosin modification (adhesive rosin composition TMAS3N and polyamide resin ProChem DUO) containing amides of resin acids, when introduced into paper pulps made from fibrous suspensions of sulphate cellulose (unbleached and bleached) of coniferous and broad-leaved species and waste paper, different in the degree of grinding (25, 40 and 70 °ShR), contribute to the increase in the strength of interfiber bonds in paper in the z-direction. The effect of the TMAS-3N emulsion was compared with the traditionally used TM and AKD sizing emulsions. The introduction of the TMAS-3N emulsion into paper pulps (0.40 % of a. d. w.) provides the maximum increase in the strength of interfiber bonds in paper in the z-direction made from cellulose, equal to 16.7–88.6 %, and from waste paper – 19.4–75.4 %, which is 1.6–6.4 and 2.3–4.5 times more compared to TM emulsion, respectively. The achieved positive effect is due to the presence in the TMAS-3H emulsion of particles of the dispersed phase of hydroxyethylamides and aminoethyl ethers capable of forming hydrogen bonds with hydroxyl groups on the mating surfaces of cellulose fibers. Sizing paper stocks with AKD emulsion reduces the strength of interfiber bonds in paper in the z-direction over the entire range of paper content studied. Polyamide resin ProChem DUO, which is a polyaminoamide of rosin resin acids, at its content in paper stocks of 0.10 %, increases the strength of interfiber bonds in paper in the z-direction, made from cellulose and waste paper suspensions, by 50.0–92.3 and 44.4–63.5 %, respectively. The obtained results of increasing the strength of interfiber bonds in paper in the z-direction by resin acid amides of rosin are in full agreement with the mechanism of bridged bonds and the theory of hydrogen bonds.
{"title":"Influence of rosin resin acids amides on the strength of interfiber bonds in paper in the z-direction","authors":"V. Fleisher","doi":"10.29235/1561-8331-2022-58-4-407-417","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-407-417","url":null,"abstract":"Resin acid amides of rosin, depending on the structure, can have both a hydrophobizing and hardening effect on paper pulps. It has been established that the developed products of rosin modification (adhesive rosin composition TMAS3N and polyamide resin ProChem DUO) containing amides of resin acids, when introduced into paper pulps made from fibrous suspensions of sulphate cellulose (unbleached and bleached) of coniferous and broad-leaved species and waste paper, different in the degree of grinding (25, 40 and 70 °ShR), contribute to the increase in the strength of interfiber bonds in paper in the z-direction. The effect of the TMAS-3N emulsion was compared with the traditionally used TM and AKD sizing emulsions. The introduction of the TMAS-3N emulsion into paper pulps (0.40 % of a. d. w.) provides the maximum increase in the strength of interfiber bonds in paper in the z-direction made from cellulose, equal to 16.7–88.6 %, and from waste paper – 19.4–75.4 %, which is 1.6–6.4 and 2.3–4.5 times more compared to TM emulsion, respectively. The achieved positive effect is due to the presence in the TMAS-3H emulsion of particles of the dispersed phase of hydroxyethylamides and aminoethyl ethers capable of forming hydrogen bonds with hydroxyl groups on the mating surfaces of cellulose fibers. Sizing paper stocks with AKD emulsion reduces the strength of interfiber bonds in paper in the z-direction over the entire range of paper content studied. Polyamide resin ProChem DUO, which is a polyaminoamide of rosin resin acids, at its content in paper stocks of 0.10 %, increases the strength of interfiber bonds in paper in the z-direction, made from cellulose and waste paper suspensions, by 50.0–92.3 and 44.4–63.5 %, respectively. The obtained results of increasing the strength of interfiber bonds in paper in the z-direction by resin acid amides of rosin are in full agreement with the mechanism of bridged bonds and the theory of hydrogen bonds.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89267205","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}
Pub Date : 2022-11-28DOI: 10.29235/1561-8331-2022-58-4-351-359
I. Matsukevich, E. D. Yundel, N. Kulinich, Y. Yahorava, L. Kulbitskaya, T. F. Kuznetsova
Mesoporous CeO2 and MgO powders and nanocomposites based on them were synthesized by the method of self-propagating high-temperature synthesis, and the mutual influence of magnesium oxide and cerium oxide on the crystal structure, microstructure, and morphology of the obtained materials was studied. It has been established that CeO2 is formed on the surface of magnesium oxide, while the developed surface of the material is preserved. It has been established, that the sizes of CeO2 crystallites in the composition of nanocomposites change insignificantly and range from 6.5 to 7.4 nm, while the values of the specific surface area and average pore diameter of the studied samples depend on the composition and vary in the ranges of 19–41 m2/g and 11.9‒19 nm, respectively. The highest efficiency of photodegradation of dyes of acid telon blue and direct bright blue is observed for samples of MgO–CeO2 (30 mol.%) and MgO–CeO2 (50 mol.%) ‒ 98.5 and 92.5 %, respectively, taking into account the effect of direct photolytic decomposition under the influence of ultraviolet radiation.
{"title":"Preparation, structure and photocatalytic activity of nanocomposites based on cerium oxide","authors":"I. Matsukevich, E. D. Yundel, N. Kulinich, Y. Yahorava, L. Kulbitskaya, T. F. Kuznetsova","doi":"10.29235/1561-8331-2022-58-4-351-359","DOIUrl":"https://doi.org/10.29235/1561-8331-2022-58-4-351-359","url":null,"abstract":"Mesoporous CeO2 and MgO powders and nanocomposites based on them were synthesized by the method of self-propagating high-temperature synthesis, and the mutual influence of magnesium oxide and cerium oxide on the crystal structure, microstructure, and morphology of the obtained materials was studied. It has been established that CeO2 is formed on the surface of magnesium oxide, while the developed surface of the material is preserved. It has been established, that the sizes of CeO2 crystallites in the composition of nanocomposites change insignificantly and range from 6.5 to 7.4 nm, while the values of the specific surface area and average pore diameter of the studied samples depend on the composition and vary in the ranges of 19–41 m2/g and 11.9‒19 nm, respectively. The highest efficiency of photodegradation of dyes of acid telon blue and direct bright blue is observed for samples of MgO–CeO2 (30 mol.%) and MgO–CeO2 (50 mol.%) ‒ 98.5 and 92.5 %, respectively, taking into account the effect of direct photolytic decomposition under the influence of ultraviolet radiation.","PeriodicalId":20798,"journal":{"name":"Proceedings of the National Academy of Sciences of Belarus, Chemical Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73809309","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}
Pub Date : 2022-11-28DOI: 10.29235/1561-8331-2022-58-4-360-368
E. G. Karankevich, Z. Kuvaeva, L. Kulbitskaya, A. Popov
The effect of the crystallization conditions of modafinil from its methanol solutions on the polymorphic state of the resulting substance was studied using the X-ray powder diffraction method. It is shown that changes in the cooling rate and the concentration of saturated solutions have an effect on obtaining samples of the modafinil substance with differences in diffractometric characteristics. Moreover, the cooling rate practically does not affect the yield of the crystalline product, which depends on the degree of saturation of crystallization solutions. It was found that the I polymorphic form of modafinil can be obtained from modafinil solutions with a concentration in the range of 0.34–0.44 M with slow cooling of solutions, mainly with a temperature gradient of 5–10 °C/hour to a temperature of 5 ± 2 °C. An increase in the cooling rate of saturated solutions and their concentration >0.44 M leads to the production of mixed polymorphic forms of modafinil crystals.
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