Viacheslav Shvydkiy, S. Dolgov, Alexander Dubovik, Mikhail Kozlov, A. Povkh, L. Shishkina, G. Duca
This paper presents a study of the hydrochemical composition and physicochemical properties of natural water samples from various sources in the Voronezh and Moscow regions. Two model systems are proposed for assessing the state of the aquatic environment: UV spectroscopy with spectrum decomposition by the Gauss method and spontaneous aggregation of lecithin in a polar medium. Based on the performed investigation, it was determined that the size of lecithin aggregates decreases, and the value of their zeta potential increases with an increase in the content of hydrophobic compounds in natural water.
{"title":"New Aspects for the Estimation of the State of the Natural Water","authors":"Viacheslav Shvydkiy, S. Dolgov, Alexander Dubovik, Mikhail Kozlov, A. Povkh, L. Shishkina, G. Duca","doi":"10.19261/cjm.2022.973","DOIUrl":"https://doi.org/10.19261/cjm.2022.973","url":null,"abstract":"This paper presents a study of the hydrochemical composition and physicochemical properties of natural water samples from various sources in the Voronezh and Moscow regions. Two model systems are proposed for assessing the state of the aquatic environment: UV spectroscopy with spectrum decomposition by the Gauss method and spontaneous aggregation of lecithin in a polar medium. Based on the performed investigation, it was determined that the size of lecithin aggregates decreases, and the value of their zeta potential increases with an increase in the content of hydrophobic compounds in natural water.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"11 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78841403","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}
Dhanraj Kamble, A. Shankarwar, Yuvraj P. Sarnikar, Radhakrushna Tigote, M. Shaikh, Pravin N. Chavan
Herein, an efficient one-pot synthesis is described, of substituted benzimidazole derivatives (3a-j) from a condensation of various o-phenylenediamine (1a-j) aromatic aldehyde (2a-j) using ZnFe2O4 as a nano-catalyst under ultrasonic irradiation conditions. All forms of aldehydes with an electron releasing or electron –withdrawing substituent have a significant yield. The catalyst can easily be recovered after completion of the reaction and reused without affecting its activity. Prepared benzimidazole derivatives showed moderate to good anti-tuberculosis results.
{"title":"One-pot Synthesis of Substituted Benzimidazole Derivatives under Ultrasonic Irradiation Using ZnFe2O4 Reusable Catalyst","authors":"Dhanraj Kamble, A. Shankarwar, Yuvraj P. Sarnikar, Radhakrushna Tigote, M. Shaikh, Pravin N. Chavan","doi":"10.19261/cjm.2022.892","DOIUrl":"https://doi.org/10.19261/cjm.2022.892","url":null,"abstract":"Herein, an efficient one-pot synthesis is described, of substituted benzimidazole derivatives (3a-j) from a condensation of various o-phenylenediamine (1a-j) aromatic aldehyde (2a-j) using ZnFe2O4 as a nano-catalyst under ultrasonic irradiation conditions. All forms of aldehydes with an electron releasing or electron –withdrawing substituent have a significant yield. The catalyst can easily be recovered after completion of the reaction and reused without affecting its activity. Prepared benzimidazole derivatives showed moderate to good anti-tuberculosis results.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"66 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89463858","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}
A facile, one-pot, and solvent-free synthesis was developed to obtain a thermally stable chitosan biopolymer. The bifunctional isocyanate by interaction with chitosan formed urea and urethane bonds between chitosan chains. Subsequently, the designed chemistry facilitated the formation of carbodiimide bonds between chitosan chains via dehydration of the urea bond. The modified chitosan was proved to be superior in thermal properties and could be used as a thermally stable bio-filler. This synthetic methodology is a facile route to achieve improved thermal stability in biopolymers.
{"title":"One-pot and Solvent-free Synthesis of Carbodiimide Modified Chitosan; Extraordinary Thermally Stability","authors":"Jesna Das, Sidharth Mohan, Simi Chandroth Kalyad","doi":"10.19261/cjm.2022.895","DOIUrl":"https://doi.org/10.19261/cjm.2022.895","url":null,"abstract":"A facile, one-pot, and solvent-free synthesis was developed to obtain a thermally stable chitosan biopolymer. The bifunctional isocyanate by interaction with chitosan formed urea and urethane bonds between chitosan chains. Subsequently, the designed chemistry facilitated the formation of carbodiimide bonds between chitosan chains via dehydration of the urea bond. The modified chitosan was proved to be superior in thermal properties and could be used as a thermally stable bio-filler. This synthetic methodology is a facile route to achieve improved thermal stability in biopolymers.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"99 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81296062","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 paper presents original results on the of nitric acid concentrations effect on structure, morphology, protolytic properties and the activity of low-temperature carbon monoxide oxidation catalysts based on acid-modified phlogopite (Н-Phl-1) and K2PdCl4, Cu(NO3)2, KBr base components. The obtained samples were characterized by XRD, SEM, FT-IR spectroscopy and pH metric method. The obtained catalyst Pd(II)-Cu(II)/8H-Phl-1 can be recommended for use in respiratory devices.
{"title":"Influence of Acid Modification of Natural Phlogopite on Catalytic Activity of Supported Pd(II)-Cu(II) Complexes in the Reaction of Oxidation of Carbon Monoxide by Atmospheric Oxygen","authors":"A. Nazar, T. Rakitskaya, Tatyana Kios","doi":"10.19261/cjm.2022.927","DOIUrl":"https://doi.org/10.19261/cjm.2022.927","url":null,"abstract":"The paper presents original results on the of nitric acid concentrations effect on structure, morphology, protolytic properties and the activity of low-temperature carbon monoxide oxidation catalysts based on acid-modified phlogopite (Н-Phl-1) and K2PdCl4, Cu(NO3)2, KBr base components. The obtained samples were characterized by XRD, SEM, FT-IR spectroscopy and pH metric method. The obtained catalyst Pd(II)-Cu(II)/8H-Phl-1 can be recommended for use in respiratory devices.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"31 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90247156","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}
A. Ivanchenko, D. Yelatontsev, A. Savenkov, O. Nazarenko, Viktoria Kundirenko
An environmentally friendly method for phosphogypsum processing into N,Ca,S,P-fertilizers is proposed. Thus, was obtained a complex liquid N,Ca,S,P-fertilizer with the content of nutrients (% wt.) N:Ca:S:P = 56:26:12:6 in the dry product, and 16.8:3.6:7.8:1.8 in the liquid phase. The obtained fertilizer increased the yield of radish by 7.16% compared to the control. The advantage of the proposed method is reducing the cost of the fertilizer, increasing its nutritional value, and obtaining useful products from the waste.
{"title":"Obtaining of Complex Mineral Fertilizer by Phosphogypsum Conversion with Ammonium Nitrate","authors":"A. Ivanchenko, D. Yelatontsev, A. Savenkov, O. Nazarenko, Viktoria Kundirenko","doi":"10.19261/cjm.2021.902","DOIUrl":"https://doi.org/10.19261/cjm.2021.902","url":null,"abstract":"An environmentally friendly method for phosphogypsum processing into N,Ca,S,P-fertilizers is proposed. Thus, was obtained a complex liquid N,Ca,S,P-fertilizer with the content of nutrients (% wt.) N:Ca:S:P = 56:26:12:6 in the dry product, and 16.8:3.6:7.8:1.8 in the liquid phase. The obtained fertilizer increased the yield of radish by 7.16% compared to the control. The advantage of the proposed method is reducing the cost of the fertilizer, increasing its nutritional value, and obtaining useful products from the waste.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"171 ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72444013","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 effect of halide ions (X= Cl−, Br−, I−) on the kinetics of ozone decomposition by compositions supported on the natural bentonite of the Dashukovske deposit in Ukraine (N-Bent(D)) has been studied. The obtained results have shown that the activity of the KX/N-Bent(D) composition in the ozone decomposition reaction increases in the row KCl << KBr < KI, which correlates with an increase in their reducing properties (the redox potential of the Х2/2Х− pair decreases). Such catalyst compositions can be recommended for applying in personal protective equipment for the respiratory system.
{"title":"The Effect of Halide Ions on the Activity of D-metal Complexes Supported on Natural Bentonite in the Reaction of Low Temperature Ozone Decomposition","authors":"T. Rakitskaya, A. Truba, G. Dzhyga","doi":"10.19261/cjm.2021.912","DOIUrl":"https://doi.org/10.19261/cjm.2021.912","url":null,"abstract":"The effect of halide ions (X= Cl−, Br−, I−) on the kinetics of ozone decomposition by compositions supported on the natural bentonite of the Dashukovske deposit in Ukraine (N-Bent(D)) has been studied. The obtained results have shown that the activity of the KX/N-Bent(D) composition in the ozone decomposition reaction increases in the row KCl << KBr < KI, which correlates with an increase in their reducing properties (the redox potential of the Х2/2Х− pair decreases). Such catalyst compositions can be recommended for applying in personal protective equipment for the respiratory system.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"24 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79173227","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}
Four new {Cr8} rings have been synthesized and characterized; they are all based on the classic [CrF(O2CtBu)2]8 ring 1. Three routes have been studied. The first is direct synthesis, by reacting hydrated chromium(III) fluorides with the acid; this has been used to produce LS[CrF(O2CEt)2]8 3. The second route uses 3 as a precursor and substitute with an incoming carboxylate. This has been used to make [CrF(O2CCCl3)2]8 4 and [CrF(O2CC6F5)2]8 5. The third route uses LSN-ethyl-D-glucamine (H5Etglu) as a template and produces chiral rings [Cr8F4(Etglu)(O2CtBu)15] 6. The single crystal X-ray structures of these new compounds are reported.
合成并表征了四个新的{Cr8}环;它们都是基于经典的[CrF(O2CtBu)2]8环1。研究了三条路线。第一种是直接合成,通过与酸反应水合氟化铬(III);这已被用于生产LS[CrF(O2CEt)2]8。第二种途径使用3作为前体并用进入的羧酸盐代替。这已被用于制造[CrF(O2CCCl3)2] 84和[CrF(O2CC6F5)2] 85。第三种途径以lsn -乙基- d -氨基葡萄糖(H5Etglu)为模板,生成手性环[Cr8F4(Etglu)(O2CtBu)15] 6。报道了这些新化合物的单晶x射线结构。
{"title":"New Homometallic Octanuclear Chromium(III) Rings","authors":"G. Timco, R. Pritchard, G. Whitehead, R. Winpenny","doi":"10.19261/cjm.2022.928","DOIUrl":"https://doi.org/10.19261/cjm.2022.928","url":null,"abstract":"Four new {Cr8} rings have been synthesized and characterized; they are all based on the classic [CrF(O2CtBu)2]8 ring 1. Three routes have been studied. The first is direct synthesis, by reacting hydrated chromium(III) fluorides with the acid; this has been used to produce LS[CrF(O2CEt)2]8 3. The second route uses 3 as a precursor and substitute with an incoming carboxylate. This has been used to make [CrF(O2CCCl3)2]8 4 and [CrF(O2CC6F5)2]8 5. The third route uses LSN-ethyl-D-glucamine (H5Etglu) as a template and produces chiral rings [Cr8F4(Etglu)(O2CtBu)15] 6. The single crystal X-ray structures of these new compounds are reported.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"300 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79683295","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}
A. Ryskaliyeva, Murat Baltabayev, Yerassyl Mukhamediyar, R. Iskendirova
On the basis of a new model of chemical dissolution, an analysis of the kinetic parameters obtained using the modified V.V. Dolivo-Dobrovolsky equation was carried out. It shows that the change in parameters during the transition from one mineral to another is subject to a compensation effect. Additionally, calculations based on the new dissolution model made it possible to distinguish between the systemic and individual properties of minerals of the same nature in the process of dissolution. These minerals differ from each other by the concentration of ac tive surface complexes, and are combined into a system by a single transmission coefficient and the same value of the lifetime of the active complex.
{"title":"A New Model of Chemical Dissolution of Solids: an Analysis of the Mechanism of Dissolution of Monodispersed Materials","authors":"A. Ryskaliyeva, Murat Baltabayev, Yerassyl Mukhamediyar, R. Iskendirova","doi":"10.19261/cjm.2021.859","DOIUrl":"https://doi.org/10.19261/cjm.2021.859","url":null,"abstract":"On the basis of a new model of chemical dissolution, an analysis of the kinetic parameters obtained using the modified V.V. Dolivo-Dobrovolsky equation was carried out. It shows that the change in parameters during the transition from one mineral to another is subject to a compensation effect. Additionally, calculations based on the new dissolution model made it possible to distinguish between the systemic and individual properties of minerals of the same nature in the process of dissolution. These minerals differ from each other by the concentration of ac tive surface complexes, and are combined into a system by a single transmission coefficient and the same value of the lifetime of the active complex.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"60 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91323476","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 detailed mechanism of the interaction of the radical cation ABTS•+ with a number of food acids (gallic, ferulic, caffeic, vanillic, cinnamic, syringic, p-coumaric) is revealed by means of the DFT calculations. It is shown that the interaction between the neutral molecules of the studied food acids and ABTS•+ does not lead to any charge transfer from these molecules onto ABTS•+. The almost complete conversion of the ABTS radical cation into its diamagnetic derivative occurs due to the interaction of one of the sulphonic groups of ABTS•+ with the acid anions through the formation of the corresponding intermolecular hydrogen bond.
{"title":"Some Particularities of the Reaction between Antioxidant Phenolic Acids and the Free Radical ABTS•+: a Comparative DFT Study for the Gas Phase and Ethanol","authors":"M. Gorbachev, N. Gorinchoy, I. Balan","doi":"10.19261/cjm.2021.919","DOIUrl":"https://doi.org/10.19261/cjm.2021.919","url":null,"abstract":"The detailed mechanism of the interaction of the radical cation ABTS•+ with a number of food acids (gallic, ferulic, caffeic, vanillic, cinnamic, syringic, p-coumaric) is revealed by means of the DFT calculations. It is shown that the interaction between the neutral molecules of the studied food acids and ABTS•+ does not lead to any charge transfer from these molecules onto ABTS•+. The almost complete conversion of the ABTS radical cation into its diamagnetic derivative occurs due to the interaction of one of the sulphonic groups of ABTS•+ with the acid anions through the formation of the corresponding intermolecular hydrogen bond.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"6 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82391231","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}
In this work, the stereospecific synthesis of optically active cis β-lactams under diverse microwave-induced conditions using diverse solvents was reported. The effects of low tanδ values of the solvents are found to be more crucial than solvents with high dipole moments and dielectric constants. The results indicated that for the synthesis of β-lactams solvents with low tanδ and high dipole moment and high dielectric constant are necessary. Best of the knowledge this is the first report that examined the importance of tanδ values of the solvents in β-lactams synthesis.
{"title":"Microwave-induced Conversion of Electromagnetic Energy into Heat Energy in Different Solvents: Synthesis of β-lactams","authors":"Aparna Das, R. N. Yadav, B. Banik","doi":"10.19261/cjm.2021.864","DOIUrl":"https://doi.org/10.19261/cjm.2021.864","url":null,"abstract":"In this work, the stereospecific synthesis of optically active cis β-lactams under diverse microwave-induced conditions using diverse solvents was reported. The effects of low tanδ values of the solvents are found to be more crucial than solvents with high dipole moments and dielectric constants. The results indicated that for the synthesis of β-lactams solvents with low tanδ and high dipole moment and high dielectric constant are necessary. Best of the knowledge this is the first report that examined the importance of tanδ values of the solvents in β-lactams synthesis.","PeriodicalId":9922,"journal":{"name":"Chemistry Journal of Moldova","volume":"26 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91316656","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}