In this study, new ligand was prepared by condensation reaction between Ibuprofen and 5-amino salicylic acid (IAS), this prepared ligand was used to prepare three complexes of triorgnotin(IV) salts to obtain the corresponding complexes. The ligand (IAS) and complexes were characterized by several techniques such as infrared spectroscopy, (tin, proton and carbon) magnetic resonance (1H, 13C, 119Sn NMR), elemental analyses. The antioxidant activity of the complexes was also studied. It was produced by two methods: DPPH and CUPRAC. The resulting complexes gave a higher rate of inhibition than the ligand due to the presence of the tin element in the complexes. Complex 1 (tri phenyltin-IAS) also shown greater antioxidant activity than the other compounds. KEY WORDS: Ligand, Antioxidant activity, Triorganotin(IV), DPPH method, CUPRAC method Bull. Chem. Soc. Ethiop. 2024, 38(5), 1329-1336. DOI: https://dx.doi.org/10.4314/bcse.v38i5.11
{"title":"Antioxidant properties of triphenyltin(IV) complexes derived from a novel ibuprofen-5-aminosalicylic acid ligand: synthesis and characterization","authors":"Mohanned Ali Abed-AL Zahra, Angham G. Hadi","doi":"10.4314/bcse.v38i5.11","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.11","url":null,"abstract":"In this study, new ligand was prepared by condensation reaction between Ibuprofen and 5-amino salicylic acid (IAS), this prepared ligand was used to prepare three complexes of triorgnotin(IV) salts to obtain the corresponding complexes. The ligand (IAS) and complexes were characterized by several techniques such as infrared spectroscopy, (tin, proton and carbon) magnetic resonance (1H, 13C, 119Sn NMR), elemental analyses. The antioxidant activity of the complexes was also studied. It was produced by two methods: DPPH and CUPRAC. The resulting complexes gave a higher rate of inhibition than the ligand due to the presence of the tin element in the complexes. Complex 1 (tri phenyltin-IAS) also shown greater antioxidant activity than the other compounds. \u0000KEY WORDS: Ligand, Antioxidant activity, Triorganotin(IV), DPPH method, CUPRAC method \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1329-1336. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.11","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abdulqadier Hussien Al khazraji, Mostefe Khalid Mohammed, Alaa Hasan Fahmi, Sahar H. Mourad
γ-Al2O3 nanoparticles have been synthesized using aluminium(III) sulfate as a source of metal. Ceratonia silique leaves extract was used as a reducing agent and sodium hydroxide solution as a precipitating. XRD, BET, FE-SEM, EDX, and DLS Techniques were used to characterize the prepared alumina. The desulfurization process was applied by adsorption of sulfur compounds from Iraqi crude oil using the prepared γ-Al2O3 nanoparticles. The efficiency of aluminium oxide nanoparticles as an adsorbent was studied for different factors such as adsorbent quantity, contact time, pH, and temperature. The average size of γ-Al2O3 nanoparticles is 12.44 nm, with a size distribution of particles from 90 nm to 900 nm. The mixture was drained at 80 ºC, and then calcined at 600 ºC, BET analysis shows a high surface area (72.03 m2 g-1) and uniform pore sizes of Al2O3 NPs. The FE-SEM images showed that the nanoparticles appeared smooth and cylinder-shaped within the average size of 100.53 nm. The obtained results of removal of the sulfur compounds from crude oil using γ-Al2O3 nanoparticles showed a high desulfurization and were achieved with adsorbent at specific conditions: 150 min, 0.5 g of adsorbent, temperature at 25 ºC and acidic medium pH = 2. KEY WORDS: Crude oil, γ-Al2O3 nanoparticles, Ceratonia siliqua leaves extract Bull. Chem. Soc. Ethiop. 2024, 38(5), 1241-1250. DOI: https://dx.doi.org/10.4314/bcse.v38i5.4
{"title":"Removal of sulfur compounds from Iraqi crude oil using γ-Al2O3 nanoparticles","authors":"Abdulqadier Hussien Al khazraji, Mostefe Khalid Mohammed, Alaa Hasan Fahmi, Sahar H. Mourad","doi":"10.4314/bcse.v38i5.4","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.4","url":null,"abstract":"γ-Al2O3 nanoparticles have been synthesized using aluminium(III) sulfate as a source of metal. Ceratonia silique leaves extract was used as a reducing agent and sodium hydroxide solution as a precipitating. XRD, BET, FE-SEM, EDX, and DLS Techniques were used to characterize the prepared alumina. The desulfurization process was applied by adsorption of sulfur compounds from Iraqi crude oil using the prepared γ-Al2O3 nanoparticles. The efficiency of aluminium oxide nanoparticles as an adsorbent was studied for different factors such as adsorbent quantity, contact time, pH, and temperature. The average size of γ-Al2O3 nanoparticles is 12.44 nm, with a size distribution of particles from 90 nm to 900 nm. The mixture was drained at 80 ºC, and then calcined at 600 ºC, BET analysis shows a high surface area (72.03 m2 g-1) and uniform pore sizes of Al2O3 NPs. The FE-SEM images showed that the nanoparticles appeared smooth and cylinder-shaped within the average size of 100.53 nm. The obtained results of removal of the sulfur compounds from crude oil using γ-Al2O3 nanoparticles showed a high desulfurization and were achieved with adsorbent at specific conditions: 150 min, 0.5 g of adsorbent, temperature at 25 ºC and acidic medium pH = 2. \u0000KEY WORDS: Crude oil, γ-Al2O3 nanoparticles, Ceratonia siliqua leaves extract \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1241-1250. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.4 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tanu Arora, Km. Garima, Vikas Kumar, Saleem Javed, Mohammad Azam, Saud I. Al-Resayes, Nivedita Agnihotri
Transition metal complexes are an appealing target in the development of functional materials used frequently in industrial and therapeutic world. The quantum chemical investigations help to obtain a thorough comprehension of the interplay between complexes and biological materials. It necessitates sufficient modeling of chemical phenomena in the system, occasionally involving assistance of classical or semi-empirical computational techniques. Identification of the factors influencing complexes and their optimization is essential for electronic structure calculations and the relevant biochemical potential. The present study aims at correlating analytical studies with the theoretical behavior involving identification of structural features and bonding interactions of the three 4H-1-benzopyrans and their spectrophotometrically analyzed palladium complexes using DFT calculations to get acquainted with pharmacological profile of the complexes. FMO studies indicated a higher Egap for ligand in all the cases than their respective Pd(II) complexes. Furthermore, according to the other chemical descriptors, interaction between the ligands and respective complexes, cause chromogenic ligand’s chemical hardness to decrease indicating that the formed complexes have lower kinetic stability and more chemical reactivity. Efficiency of the studied ligands further was analyzed by molecular docking against the target proteins, of which 2O0U, a transferase exhibited mutual interactions with all the examined ligands. KEY WORDS: Palladium(II), 4H-1-benzopyran complexes, DFT, MEP, Molecular docking Bull. Chem. Soc. Ethiop. 2024, 38(5), 1311-1327. DOI: https://dx.doi.org/10.4314/bcse.v38i5.10
{"title":"Spectrophotometric, quantum chemical and molecular docking investigations of 4H-1-benzopyran-derived Pd(II) complexes","authors":"Tanu Arora, Km. Garima, Vikas Kumar, Saleem Javed, Mohammad Azam, Saud I. Al-Resayes, Nivedita Agnihotri","doi":"10.4314/bcse.v38i5.10","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.10","url":null,"abstract":"Transition metal complexes are an appealing target in the development of functional materials used frequently in industrial and therapeutic world. The quantum chemical investigations help to obtain a thorough comprehension of the interplay between complexes and biological materials. It necessitates sufficient modeling of chemical phenomena in the system, occasionally involving assistance of classical or semi-empirical computational techniques. Identification of the factors influencing complexes and their optimization is essential for electronic structure calculations and the relevant biochemical potential. The present study aims at correlating analytical studies with the theoretical behavior involving identification of structural features and bonding interactions of the three 4H-1-benzopyrans and their spectrophotometrically analyzed palladium complexes using DFT calculations to get acquainted with pharmacological profile of the complexes. FMO studies indicated a higher Egap for ligand in all the cases than their respective Pd(II) complexes. Furthermore, according to the other chemical descriptors, interaction between the ligands and respective complexes, cause chromogenic ligand’s chemical hardness to decrease indicating that the formed complexes have lower kinetic stability and more chemical reactivity. Efficiency of the studied ligands further was analyzed by molecular docking against the target proteins, of which 2O0U, a transferase exhibited mutual interactions with all the examined ligands. \u0000KEY WORDS: Palladium(II), 4H-1-benzopyran complexes, DFT, MEP, Molecular docking \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1311-1327. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.10 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haewon Byeon, M. S. Sivagama Sundari, Ilango Karuppasamy, R. S. Jayaram
The ceramic lanthanum nanoparticles with uniformly dispersed spherical nanostructures were successfully synthesized using sonication-assisted synthesis. The morphologies and phase compositions were assessed and investigated. The electrochemical impedance analysis potentio-dynamic polarisation measurements were used to calculate the corrosion protection properties of prepared ceramic lanthanum nanoparticles. The La2O3 nanoparticles were added as a surface coating layer to enhance the corrosion resistance of low-carbon steel. The particles' impact on coating development, morphology, and corrosion inhibition efficacy were studied. After particle integration, results show a dramatic reduction in porosity and thickness, affecting corrosion resistance. Incorporating ceramic lanthanum nanoparticles into a coating reduces porosity and increases hardness, improving corrosion resistance; the result implies the suggested technique is viable for creating functionalized coatings on low-carbon-based materials. The results also demonstrated that these methods may increase the development and protectiveness of the coating. There was a crucial nano particulate La2O3 level at which the conversion coatings exhibited the best protective qualities. As it increased the corrosion potential and lowered the anodic current, the composite La-conversion coatings may offer substantial corrosion protection for prolonged immersion in a 3.5% NaCl solution. KEY WORDS: Ceramic nanoparticles, Low carbon steel, Corrosion prevention, Polarization Bull. Chem. Soc. Ethiop. 2024, 38(5), 1453-1468. DOI: https://dx.doi.org/10.4314/bcse.v38i5.20
{"title":"A novel composite la-conversion coatings for enhanced anti-corrosion performance under a harsh aqueous environment","authors":"Haewon Byeon, M. S. Sivagama Sundari, Ilango Karuppasamy, R. S. Jayaram","doi":"10.4314/bcse.v38i5.20","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.20","url":null,"abstract":"The ceramic lanthanum nanoparticles with uniformly dispersed spherical nanostructures were successfully synthesized using sonication-assisted synthesis. The morphologies and phase compositions were assessed and investigated. The electrochemical impedance analysis potentio-dynamic polarisation measurements were used to calculate the corrosion protection properties of prepared ceramic lanthanum nanoparticles. The La2O3 nanoparticles were added as a surface coating layer to enhance the corrosion resistance of low-carbon steel. The particles' impact on coating development, morphology, and corrosion inhibition efficacy were studied. After particle integration, results show a dramatic reduction in porosity and thickness, affecting corrosion resistance. Incorporating ceramic lanthanum nanoparticles into a coating reduces porosity and increases hardness, improving corrosion resistance; the result implies the suggested technique is viable for creating functionalized coatings on low-carbon-based materials. The results also demonstrated that these methods may increase the development and protectiveness of the coating. There was a crucial nano particulate La2O3 level at which the conversion coatings exhibited the best protective qualities. As it increased the corrosion potential and lowered the anodic current, the composite La-conversion coatings may offer substantial corrosion protection for prolonged immersion in a 3.5% NaCl solution. \u0000KEY WORDS: Ceramic nanoparticles, Low carbon steel, Corrosion prevention, Polarization \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1453-1468. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.20 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Desta G. Woldegiorgis, Ephriem T. Mengesha, N. Babu G., Maria Susai Boobalan, Taye B. Demissie, E. Teju
The mechanism of dual fluorescence emission of a fluorophore is controversial ever since its first observation in p-N,N-dimethylaminobenzonitrile (DMABN). Excited state twisted intramolecular charge transfer (TICT) and planarized intramolecular charge transfer (PICT) models have been the two prominent theories used to explain the dual fluorescence mechanism in several systems. These mechanisms are based on excited state adiabatic structural changes of the fluorophore. Nevertheless, pieces of evidences based on excitation spectral measurements at different emission windows suggest the possibility of additional and/or alternative mechanisms based on ground state structural changes of the fluorophore. In this paper, we have presented a systematic steady-state absorption and fluorescence spectroscopy of a donor-πacceptor system, p-N,N-(dialkylamino)benzylidenemalononitrile, and related compounds in solvents of different polarities. The excitation spectrum of p-N,N-(dialkylamino) benzylidenemalononitrile is found to be dependent on the emission window. Furthermore, the emission spectra of the molecule are dependent on the excitation wavelength which suggest that the molecule consists of two stable ground state conformational isomers. The spectroscopic pieces of evidence together with results from DFT calculations are in favor of the solvent-induced ground state structural change of the fluorophore. Hence, two ground state conformers of p-N,N-(dialkylamino)benzylidenemalononitrile are attributed to the dual emission of the molecule. KEY WORDS: Dual fluorescence, Charge transfer, TICT, PICT, Excitation, Benzylidenemalononitriles Bull. Chem. Soc. Ethiop. 2024, 38(5), 1413-1427. DOI: https://dx.doi.org/10.4314/bcse.v38i5.17
{"title":"Dual fluorescence emission of p-N,N-(dialkylamino) benzyl-idenemalononitrile and related systems: Evidence for direct excitation of ground state twisted intramolecular charge transfer (TICT) conformer","authors":"Desta G. Woldegiorgis, Ephriem T. Mengesha, N. Babu G., Maria Susai Boobalan, Taye B. Demissie, E. Teju","doi":"10.4314/bcse.v38i5.17","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.17","url":null,"abstract":"The mechanism of dual fluorescence emission of a fluorophore is controversial ever since its first observation in p-N,N-dimethylaminobenzonitrile (DMABN). Excited state twisted intramolecular charge transfer (TICT) and planarized intramolecular charge transfer (PICT) models have been the two prominent theories used to explain the dual fluorescence mechanism in several systems. These mechanisms are based on excited state adiabatic structural changes of the fluorophore. Nevertheless, pieces of evidences based on excitation spectral measurements at different emission windows suggest the possibility of additional and/or alternative mechanisms based on ground state structural changes of the fluorophore. In this paper, we have presented a systematic steady-state absorption and fluorescence spectroscopy of a donor-πacceptor system, p-N,N-(dialkylamino)benzylidenemalononitrile, and related compounds in solvents of different polarities. The excitation spectrum of p-N,N-(dialkylamino) benzylidenemalononitrile is found to be dependent on the emission window. Furthermore, the emission spectra of the molecule are dependent on the excitation wavelength which suggest that the molecule consists of two stable ground state conformational isomers. The spectroscopic pieces of evidence together with results from DFT calculations are in favor of the solvent-induced ground state structural change of the fluorophore. Hence, two ground state conformers of p-N,N-(dialkylamino)benzylidenemalononitrile are attributed to the dual emission of the molecule. \u0000KEY WORDS: Dual fluorescence, Charge transfer, TICT, PICT, Excitation, Benzylidenemalononitriles \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1413-1427. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.17 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Genet Bekele, Abebaw A. Tsegaye, Abi M. Taddesse, E. Teju
Magnetite and zirconium oxide (Fe3O4/ZrO2) nano composite, Fe3O4 and ZrO2 nanoparticles were synthesized by a chemical co-precipitation method and hydrothermal decomposition of zirconium metal organic framework, respectively. The structural and morphological properties of the as-synthesized materials were characterized by X-ray diffraction and scanning electron microscope. Electrochemical properties of carbon paste electrode (CPE) modified by Fe3O4, ZrO2 and Fe3O4/ZrO2 nano composites were studied using cyclic voltammetry and electrochemical impedance spectroscopy in the presence of 2 mM K3Fe(CN)6/0.1 M KCl aqueous solution. Voltammograms acquired on Fe3O4/ZrO2/CPE showed an enhancement of the oxidation current density compared to the other modified electrodes. By applying the Randles-Sevcik equation, the CPE modified by Fe3O4/ZrO2 nano composite resulted in an electroactive surface area of 0.0978 cm2; about twice to that of the unmodified CPE (0.0458 cm2). The electrochemical sensor was used for the detection of ascorbic acid (AA). Under optimized condition (pH 4) the sensor exhibits sensitivity of 10 µA/µM; LOD of 0.46 µM; LOQ of 1.53 µM and a linear range of 1-6 μM AA. The Fe3O4/ZrO2/CPE has also shown accepted reproducibility (% recoveries 93.54%); RSD of 2.4% and stable response of 96.91% of the initial current after 30 days of storage. KEY WORDS: Ascorbic acid, Carbon paste electrode, Electrochemical sensor, Nano composite Bull. Chem. Soc. Ethiop. 2024, 38(5), 1205-1223. DOI: https://dx.doi.org/10.4314/bcse.v38i5.2
{"title":"A stable electrochemical sensor for the detection of ascorbic acid based on Fe3O4/ZrO2 nano composite modified carbon paste electrode","authors":"Genet Bekele, Abebaw A. Tsegaye, Abi M. Taddesse, E. Teju","doi":"10.4314/bcse.v38i5.2","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.2","url":null,"abstract":"Magnetite and zirconium oxide (Fe3O4/ZrO2) nano composite, Fe3O4 and ZrO2 nanoparticles were synthesized by a chemical co-precipitation method and hydrothermal decomposition of zirconium metal organic framework, respectively. The structural and morphological properties of the as-synthesized materials were characterized by X-ray diffraction and scanning electron microscope. Electrochemical properties of carbon paste electrode (CPE) modified by Fe3O4, ZrO2 and Fe3O4/ZrO2 nano composites were studied using cyclic voltammetry and electrochemical impedance spectroscopy in the presence of 2 mM K3Fe(CN)6/0.1 M KCl aqueous solution. Voltammograms acquired on Fe3O4/ZrO2/CPE showed an enhancement of the oxidation current density compared to the other modified electrodes. By applying the Randles-Sevcik equation, the CPE modified by Fe3O4/ZrO2 nano composite resulted in an electroactive surface area of 0.0978 cm2; about twice to that of the unmodified CPE (0.0458 cm2). The electrochemical sensor was used for the detection of ascorbic acid (AA). Under optimized condition (pH 4) the sensor exhibits sensitivity of 10 µA/µM; LOD of 0.46 µM; LOQ of 1.53 µM and a linear range of 1-6 μM AA. The Fe3O4/ZrO2/CPE has also shown accepted reproducibility (% recoveries 93.54%); RSD of 2.4% and stable response of 96.91% of the initial current after 30 days of storage. \u0000KEY WORDS: Ascorbic acid, Carbon paste electrode, Electrochemical sensor, Nano composite \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1205-1223. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.2 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. K. Manoj, U. Arunachalam, M. Mathanbabu, A. Kajavali
Thermal barrier coatings (TBCs) are often applied to base metals exposed to excessive temperatures to protect them from the harsh operating thermal cycle load conditions and to enhance their functionality. For this research, nickel and zirconia was coated over a mild steel substrate by electro-deposition or co-deposition method. While selecting appropriate electro-deposition parameters, this study analyses the convection and conduction heat transfer characteristics and mechanical behaviours of a nickel-zirconia co-deposit over a mild steel substrate. The better-quality deposition is formed with thicknesses of 10 μm and 50 μm. The microstructure and morphological analyses were conducted using scanning electron microscope (SEM). The phase analysis was conducted using X-ray diffraction analysis (XRD). The porosity, hardness and wear behaviours were measured as per the American Society for Testing and Materials (ASTM). The results showed that nickel-zirconia coating has better performance. The coating's convection and conduction heat transfer potential are investigated using a specially designed and constructed experimentation apparatus. Compared to an uncoated panel, heat transfer studies on nickel-zirconia coatings demonstrate that nano-coatings with a particle size of about 92 nm show a significant temperature drop with varied coating thicknesses and heat inputs for different heat inputs. KEY WORDS: Thermal barrier coatings, Electro deposition, Conduction heat transfer, Convection heat transfer, Nickel-Zirconia Bull. Chem. Soc. Ethiop. 2024, 38(5), 1439-1452. DOI: https://dx.doi.org/10.4314/bcse.v38i5.19
{"title":"Mechanical and heat transfer behaviour of electro-deposited nickel-zirconia coating","authors":"J. K. Manoj, U. Arunachalam, M. Mathanbabu, A. Kajavali","doi":"10.4314/bcse.v38i5.19","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.19","url":null,"abstract":"Thermal barrier coatings (TBCs) are often applied to base metals exposed to excessive temperatures to protect them from the harsh operating thermal cycle load conditions and to enhance their functionality. For this research, nickel and zirconia was coated over a mild steel substrate by electro-deposition or co-deposition method. While selecting appropriate electro-deposition parameters, this study analyses the convection and conduction heat transfer characteristics and mechanical behaviours of a nickel-zirconia co-deposit over a mild steel substrate. The better-quality deposition is formed with thicknesses of 10 μm and 50 μm. The microstructure and morphological analyses were conducted using scanning electron microscope (SEM). The phase analysis was conducted using X-ray diffraction analysis (XRD). The porosity, hardness and wear behaviours were measured as per the American Society for Testing and Materials (ASTM). The results showed that nickel-zirconia coating has better performance. The coating's convection and conduction heat transfer potential are investigated using a specially designed and constructed experimentation apparatus. Compared to an uncoated panel, heat transfer studies on nickel-zirconia coatings demonstrate that nano-coatings with a particle size of about 92 nm show a significant temperature drop with varied coating thicknesses and heat inputs for different heat inputs. \u0000KEY WORDS: Thermal barrier coatings, Electro deposition, Conduction heat transfer, Convection heat transfer, Nickel-Zirconia \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1439-1452. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.19 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jalal Abdulla Haji, Lana Hadi Chawishli, Mohammed Kareem Samad
In response to the challenge of antibiotic-resistant microorganisms, oxazolone analogs are frequently used for bacterial, antiviral, and anti-inflammatory treatments. However, few studies have shown bis-oxazolone analogs possess antibacterial activities. In this study, we modified bis-oxazolone molecules with various aromatic amines to create new bis-benzamide and bis-imidazolone derivatives. These derivatives were analyzed using FT-IR, ¹H-NMR, and ¹³C-NMR spectroscopy. Molecular docking revealed favorable interactions with DNA gyrase, with compounds 3, 4a, and 5e showing higher binding affinities than penicillin G and ampicillin. These findings suggest their potential as future antimicrobial agents. The tested compounds demonstrated efficacy against bacterial strains, particularly E. coli and S. aureus, with significant activity observed in compounds 4a, 4e, 5d, and 5e. Antioxidant activity, assessed using the DPPH method, showed bis-compounds with excellent results comparable to ascorbic acid. This encourages further studies to explore their potential. Overall, the synthesized bis-oxazolone derivatives demonstrated increased medicinal activity and high potential as future antimicrobial and antioxidant agents. KEY WORDS: Bis-oxazolone, Bis-benzamide, Bis-imidazolone, Docking study, Antibacterial, Antioxidant Bull. Chem. Soc. Ethiop. 2024, 38(5), 1393-1404. DOI: https://dx.doi.org/10.4314/bcse.v38i5.15
为了应对抗生素耐药微生物的挑战，恶唑酮类似物经常被用于细菌、抗病毒和消炎治疗。然而，很少有研究表明双噁唑酮类似物具有抗菌活性。在本研究中，我们用各种芳香胺修饰了双恶唑酮分子，创造出了新的双苯甲酰胺和双咪唑酮衍生物。我们使用傅立叶变换红外光谱、¹H-NMR 和 ¹³C-NMR 光谱分析了这些衍生物。分子对接显示，化合物 3、4a 和 5e 与 DNA 回旋酶有良好的相互作用，其结合亲和力高于青霉素 G 和氨苄西林。这些发现表明它们具有作为未来抗菌剂的潜力。所测试的化合物对细菌菌株，尤其是大肠杆菌和金黄色葡萄球菌具有疗效，其中化合物 4a、4e、5d 和 5e 具有显著的活性。使用 DPPH 法评估抗氧化活性时，发现双化合物的抗氧化效果极佳，可与抗坏血酸媲美。这有助于进一步研究探索它们的潜力。总之，合成的双噁唑酮衍生物显示出更强的药用活性，并具有作为未来抗菌剂和抗氧化剂的巨大潜力。关键词：双恶唑酮、双苯甲酰胺、双咪唑酮、对接研究、抗菌、抗氧化 Bull.Chem.Soc.2024, 38(5), 1393-1404. DOI: https://dx.doi.org/10.4314/bcse.v38i5.15
{"title":"Design, synthesis and molecular docking study of novel bis-oxazolone derivatives as potent antioxidant and antibacterial agents","authors":"Jalal Abdulla Haji, Lana Hadi Chawishli, Mohammed Kareem Samad","doi":"10.4314/bcse.v38i5.15","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.15","url":null,"abstract":"In response to the challenge of antibiotic-resistant microorganisms, oxazolone analogs are frequently used for bacterial, antiviral, and anti-inflammatory treatments. However, few studies have shown bis-oxazolone analogs possess antibacterial activities. In this study, we modified bis-oxazolone molecules with various aromatic amines to create new bis-benzamide and bis-imidazolone derivatives. These derivatives were analyzed using FT-IR, ¹H-NMR, and ¹³C-NMR spectroscopy. Molecular docking revealed favorable interactions with DNA gyrase, with compounds 3, 4a, and 5e showing higher binding affinities than penicillin G and ampicillin. These findings suggest their potential as future antimicrobial agents. The tested compounds demonstrated efficacy against bacterial strains, particularly E. coli and S. aureus, with significant activity observed in compounds 4a, 4e, 5d, and 5e. Antioxidant activity, assessed using the DPPH method, showed bis-compounds with excellent results comparable to ascorbic acid. This encourages further studies to explore their potential. Overall, the synthesized bis-oxazolone derivatives demonstrated increased medicinal activity and high potential as future antimicrobial and antioxidant agents. \u0000KEY WORDS: Bis-oxazolone, Bis-benzamide, Bis-imidazolone, Docking study, Antibacterial, Antioxidant \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1393-1404. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.15","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jemere Kochito, Olu Emmanuel Femi, Tamene Tadesse, Negera Abdisa, A. Gure
This study investigates the use of manganese oxide-biochar-nanocomposites synthesized from coffee husk (CH) and khat leftover (KL) for Cr(VI) removal from water. Two pristine biochars of CH and KL were separately synthesized by pyrolyzing their biomasses at 300 ℃ for 1 h. Similarly, biochar-based nanocomposites were synthesized by pretreating 25 g of each biomass with 12.5 mmol of KMnO4 and pyrolyzing at 300 ℃ for 1 h. The pristine biochars, synthesized by pyrolysis of CH and KL, removed 74.98% and 84.78% of Cr(VI) from aqueous solutions containing 20 mg L-1, respectively. However, the resulting nanocomposites exhibited a maximum removal efficiency of 99.63% with manganese oxide-coffee husk biochar nanocomposite (MnOX-CHBNC) and 99.84% with manganese oxide-khat leftover biochar nanocomposite (MnOX-KLBNC) of the Cr(VI). The adsorption isotherm fitted well with the Langmuir isotherm, indicating favorable monolayer adsorption. The kinetics of adsorption followed the pseudo-first-order model. The MnOX-CHBNC and MnOX-KLBNC demonstrated satisfactory removal efficiencies even up to six cycles, indicating their potential effectiveness for large-scale use in removing Cr (VI) from wastewater. KEY WORDS: Adsorption, Biochar-nanocomposite, Coffee husk, Cr(VI) removal, Khat leftovers Bull. Chem. Soc. Ethiop. 2024, 38(5), 1225-1240. DOI: https://dx.doi.org/10.4314/bcse.v38i5.3
{"title":"Manganese oxide-coffee husk and khat (Catha edulis) leftover biochar nanocomposites for removal of Cr(VI) from wastewater","authors":"Jemere Kochito, Olu Emmanuel Femi, Tamene Tadesse, Negera Abdisa, A. Gure","doi":"10.4314/bcse.v38i5.3","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.3","url":null,"abstract":"This study investigates the use of manganese oxide-biochar-nanocomposites synthesized from coffee husk (CH) and khat leftover (KL) for Cr(VI) removal from water. Two pristine biochars of CH and KL were separately synthesized by pyrolyzing their biomasses at 300 ℃ for 1 h. Similarly, biochar-based nanocomposites were synthesized by pretreating 25 g of each biomass with 12.5 mmol of KMnO4 and pyrolyzing at 300 ℃ for 1 h. The pristine biochars, synthesized by pyrolysis of CH and KL, removed 74.98% and 84.78% of Cr(VI) from aqueous solutions containing 20 mg L-1, respectively. However, the resulting nanocomposites exhibited a maximum removal efficiency of 99.63% with manganese oxide-coffee husk biochar nanocomposite (MnOX-CHBNC) and 99.84% with manganese oxide-khat leftover biochar nanocomposite (MnOX-KLBNC) of the Cr(VI). The adsorption isotherm fitted well with the Langmuir isotherm, indicating favorable monolayer adsorption. The kinetics of adsorption followed the pseudo-first-order model. The MnOX-CHBNC and MnOX-KLBNC demonstrated satisfactory removal efficiencies even up to six cycles, indicating their potential effectiveness for large-scale use in removing Cr (VI) from wastewater. \u0000KEY WORDS: Adsorption, Biochar-nanocomposite, Coffee husk, Cr(VI) removal, Khat leftovers \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1225-1240. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.3 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ni(II) metal complex of Schiff base (SB) ligand 2-methoxy-4-[(4-nitrophenyl) iminomethyl]phenol (MNIMP); derived from vanillin and 4-nitroanilline was synthesized in 1:2 M:L by refluxing solution containing metal salt (NiCl2.6H2O, 97.0%) and SB in ethanol and characterized based on powder (XRD), NMR, FT-IR, UV-Vis spectrophotometer, and physicochemical measurements. The FT-IR spectra revealed that the complex is coordinated through azomethine nitrogen and phenolic oxygen of the bi-dentate ligands. The chemical shift δ = 9.8 ppm in 1H-NMR of SB; corresponds to the azomethine proton of the ligand suggesting the presence of -C=N- linkage and 13C-NMR confirms the presence of 14C in the ligand and the complex. The shift to a lower wavelength of UV-Vis spectra of the complex compared to the ligand signifying complex formation. The powder (XRD) pattern put forward the crystalline phase of the complex through nickel(II) occupying the center of octahedron geometry. The higher molar conductance value of the complex confirms its electrolytic nature. In-vitro antibacterial activities for synthesized compounds have been evaluated towards human pathogenic microbes Staphylococcus aureus and Escherichia coli and compared with standard, gentamicin. The result demonstrated that Ni(II) complex; [Ni (MNIMP)2(H2O)2]Cl2 has greater zone of inhibition against the tested organism than free MNIMP ligand as antibacterial agent. KEY WORDS: Derivatization, Schiff base ligand, Vanillin, Nickel (II) complex, Bi-dentate, Antibacterial activity Bull. Chem. Soc. Ethiop. 2024, 38(5), 1275-1289. DOI: https://dx.doi.org/10.4314/bcse.v38i5.7
{"title":"Vanillin and 4-nitroanilline derived Schiff-base and its nickel(II) complex: spectral analysis and antibacterial investigation","authors":"Kasanesh Misganaw, Ponnusamy Thillairasu, Gemechu Shumi, Habtamu Debebe, Sintayehu Berhanu","doi":"10.4314/bcse.v38i5.7","DOIUrl":"https://doi.org/10.4314/bcse.v38i5.7","url":null,"abstract":"Ni(II) metal complex of Schiff base (SB) ligand 2-methoxy-4-[(4-nitrophenyl) iminomethyl]phenol (MNIMP); derived from vanillin and 4-nitroanilline was synthesized in 1:2 M:L by refluxing solution containing metal salt (NiCl2.6H2O, 97.0%) and SB in ethanol and characterized based on powder (XRD), NMR, FT-IR, UV-Vis spectrophotometer, and physicochemical measurements. The FT-IR spectra revealed that the complex is coordinated through azomethine nitrogen and phenolic oxygen of the bi-dentate ligands. The chemical shift δ = 9.8 ppm in 1H-NMR of SB; corresponds to the azomethine proton of the ligand suggesting the presence of -C=N- linkage and 13C-NMR confirms the presence of 14C in the ligand and the complex. The shift to a lower wavelength of UV-Vis spectra of the complex compared to the ligand signifying complex formation. The powder (XRD) pattern put forward the crystalline phase of the complex through nickel(II) occupying the center of octahedron geometry. The higher molar conductance value of the complex confirms its electrolytic nature. In-vitro antibacterial activities for synthesized compounds have been evaluated towards human pathogenic microbes Staphylococcus aureus and Escherichia coli and compared with standard, gentamicin. The result demonstrated that Ni(II) complex; [Ni (MNIMP)2(H2O)2]Cl2 has greater zone of inhibition against the tested organism than free MNIMP ligand as antibacterial agent. \u0000KEY WORDS: Derivatization, Schiff base ligand, Vanillin, Nickel (II) complex, Bi-dentate, Antibacterial activity \u0000Bull. Chem. Soc. Ethiop. 2024, 38(5), 1275-1289. \u0000DOI: https://dx.doi.org/10.4314/bcse.v38i5.7 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141834451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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