Pub Date : 2017-01-27DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.72.37
N. Rajendiran, T. Mohandoss, J. Thulasidhasan
Encapsulation of caffeic acid (CAA), ferulic acid (FEA) and sinapic acid (SIA) molecules with α-CD and β-CD was studied by UV-visible, fluorescence, time-resolved fluorescence and molecular modelling techniques. This analysis reports the probing of cyclodextrin (CD) cavities with the help of dual emission properties of the above hydroxycinnamic acids (HCAs) in aqueous solution. The normal Stokes shifted bands originated from the locally excited state and the large Stokes shifted bands due to the emission from an intramolecular charge transfer (ICT) state were observed. The ratio of the TICT emission to the normal emission increased with α-CD and β-CD concentration. CD studies indicates (i) HCAs forms 1:1 inclusion complex and (ii) acrylic group present in the interior part of the CD cavity and OH/OCH3 groups present in the upper part of the CD cavity. pH studies suggest proton transfer reactions follow the same trend in these molecules. A mechanism is proposed to explain the inclusion process. PM3 optimizations were also carried out to assign the encapsulation of the HCA molecules.
{"title":"Photophysics of Caffeic, Ferulic and Sinapic Acids with α- and β-Cyclodextrins: Spectral and Molecular Modeling Studies","authors":"N. Rajendiran, T. Mohandoss, J. Thulasidhasan","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.72.37","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.72.37","url":null,"abstract":"Encapsulation of caffeic acid (CAA), ferulic acid (FEA) and sinapic acid (SIA) molecules with α-CD and β-CD was studied by UV-visible, fluorescence, time-resolved fluorescence and molecular modelling techniques. This analysis reports the probing of cyclodextrin (CD) cavities with the help of dual emission properties of the above hydroxycinnamic acids (HCAs) in aqueous solution. The normal Stokes shifted bands originated from the locally excited state and the large Stokes shifted bands due to the emission from an intramolecular charge transfer (ICT) state were observed. The ratio of the TICT emission to the normal emission increased with α-CD and β-CD concentration. CD studies indicates (i) HCAs forms 1:1 inclusion complex and (ii) acrylic group present in the interior part of the CD cavity and OH/OCH3 groups present in the upper part of the CD cavity. pH studies suggest proton transfer reactions follow the same trend in these molecules. A mechanism is proposed to explain the inclusion process. PM3 optimizations were also carried out to assign the encapsulation of the HCA molecules.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90728893","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 : 2017-01-27DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.72.1
C. Duru, I. Duru
The efficiency of the cob, sheath, seed chaff and stalk of maize plant in the removal of Fe(II) from aqueous solutions was studied. FTIR analysis of biomass surfaces before and after adsorption showed that seed chaff has the highest number of functional group coordination points. The percentage removal of Fe(II) increased with increase in pH for all the biomass parts with highest efficiency shown by the seed chaff at all the studied pH values. Metal up-take also increased with increase in seed chaff load. This direct relationship was however not shown by other parts where decreases in metal up-take were observed at high doses of the biomass. At optimum pH and biomass load, equilibrium adsorption capacities were reached in 30 minutes for all the parts. The efficiency of the biomass parts in the sorption process were in the order seed chaff>stalk>sheath>cob. At optimum conditions of the study, the seed chaff removed 73 % of Fe(II) from solution in its natural state.
{"title":"Studies of Sorbent Efficiencies of Maize Parts in Fe(II) Removal from Aqueous Solutions","authors":"C. Duru, I. Duru","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.72.1","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.72.1","url":null,"abstract":"The efficiency of the cob, sheath, seed chaff and stalk of maize plant in the removal of Fe(II) from aqueous solutions was studied. FTIR analysis of biomass surfaces before and after adsorption showed that seed chaff has the highest number of functional group coordination points. The percentage removal of Fe(II) increased with increase in pH for all the biomass parts with highest efficiency shown by the seed chaff at all the studied pH values. Metal up-take also increased with increase in seed chaff load. This direct relationship was however not shown by other parts where decreases in metal up-take were observed at high doses of the biomass. At optimum pH and biomass load, equilibrium adsorption capacities were reached in 30 minutes for all the parts. The efficiency of the biomass parts in the sorption process were in the order seed chaff>stalk>sheath>cob. At optimum conditions of the study, the seed chaff removed 73 % of Fe(II) from solution in its natural state.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78949280","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 : 2017-01-27DOI: 10.18052/www.scipress.com/ilcpa.72.65
T. A. A. F. O. Alao
In the Policy and Ethics statement, SciPress Ltd. communicates the circumstances under which a paper can be retracted. Undertaking a retraction procedure Editors of the journal follow the COPE’s Retraction Guidelines. The author of the retracted paper is acknowledged in due course.
{"title":"Retraction Notice: F.O. Alao, T.A. Adebayo, Comparative Efficacy of Tephrosia vogelii and Moringa oleifera against Insect Pests of Watermelon (Citrullus lanatus Thumb), International Letters of Chemistry, Physics and Astronomy, Vol. 51, pp. 5-12, 2015","authors":"T. A. A. F. O. Alao","doi":"10.18052/www.scipress.com/ilcpa.72.65","DOIUrl":"https://doi.org/10.18052/www.scipress.com/ilcpa.72.65","url":null,"abstract":"In the Policy and Ethics statement, SciPress Ltd. communicates the circumstances under which a paper can be retracted. Undertaking a retraction procedure Editors of the journal follow the COPE’s Retraction Guidelines. The author of the retracted paper is acknowledged in due course.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81317606","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 : 2017-01-27DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.72.28
H. Hadi
In this work, porous silicon layers were fabricated on p-type crystalline silicon wafers using electrochemical etching ECE process. Al films were deposited onto porous layer /Si wafers by thermal evaporation to form rectifying junction. An investigation of the dependence on applied etching time to formed PS layer was studied. Effect etching time on the electrical properties of porous silicon is checked using Current–voltage I–V characteristics. The ideality factor and dynamic resistances are found to be large than the one and 20 (kΩ) respectively by the analysis of the dark I–V characteristics of Al/PS/p-Si heterojunction.
{"title":"Impact of Etching Time on Ideality Factor and Dynamic Resistance of Porous Silicon Prepared by Electrochemical Etching (ECE)","authors":"H. Hadi","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.72.28","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.72.28","url":null,"abstract":"In this work, porous silicon layers were fabricated on p-type crystalline silicon wafers using electrochemical etching ECE process. Al films were deposited onto porous layer /Si wafers by thermal evaporation to form rectifying junction. An investigation of the dependence on applied etching time to formed PS layer was studied. Effect etching time on the electrical properties of porous silicon is checked using Current–voltage I–V characteristics. The ideality factor and dynamic resistances are found to be large than the one and 20 (kΩ) respectively by the analysis of the dark I–V characteristics of Al/PS/p-Si heterojunction.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87312782","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 : 2017-01-27DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.72.9
R. Solaichamy, J. Karpagam
In this study, optimized geometry, spectroscopic (FT-IR, FT-Raman, UV) analysis, and electronic structure analysis of Abacavir were investigated by utilizing DFT/B3LYP with 6-31G(d,p) as a basis set. Complete vibrational assignments and correlation of the fundamental modes for the title compound were carried out. The calculated molecular geometry has been compared with available X-ray data of Abacavir. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The molecular stability and bond strength have been investigated by applying the Natural Bond Orbital (NBO) analysis. The computational molecular docking studies of title compound have been performed.
{"title":"Molecular Structure, Vibrational Spectra and Docking Studies of Abacavir by Density Functional Theory","authors":"R. Solaichamy, J. Karpagam","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.72.9","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.72.9","url":null,"abstract":"In this study, optimized geometry, spectroscopic (FT-IR, FT-Raman, UV) analysis, and electronic structure analysis of Abacavir were investigated by utilizing DFT/B3LYP with 6-31G(d,p) as a basis set. Complete vibrational assignments and correlation of the fundamental modes for the title compound were carried out. The calculated molecular geometry has been compared with available X-ray data of Abacavir. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The molecular stability and bond strength have been investigated by applying the Natural Bond Orbital (NBO) analysis. The computational molecular docking studies of title compound have been performed.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80385135","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 : 2016-11-01DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.71.19
Nilay Shah, P. N. Patel, D. Rajani, Denish C. Karia
In present work, novel derivatives of substituted N-(4-(8-methoxy-2-oxo-2H-chromen-3-yl) thiazol-2-yl) amide have been synthesized. The solvent free reaction of 2-Hydroxy-3-methoxybenzaldehyde with Ethyl acetoacetate in presence of Piperidine catalyst produces 3-acetyl-8-methoxy-2H-chromen-2-one (C). Compound C was α- brominated using CuBr2 and subsequently cyclized using Thiourea to produce 3-(2-aminothiazol-4-yl)-8-methoxy-2H-chromen-2-one as main scaffold (E). This scaffold E was finally reacted with different Acid chloride to isolate title compound derivatives. The chemical structures of synthesized compounds were confirmed by 1H-NMR, FT-IR and Mass spectral/LCMS analysis. The synthesized compounds were screened for potential Antimicrobial, Antifungal and Antimalarial activity.
本文合成了取代的N-(4-(8-甲氧基-2-氧-2- h -铬-3-基)噻唑-2-基)酰胺的新衍生物。在哌替啶催化下，2-羟基-3-甲氧基苯甲醛与乙酰乙酸乙酯无溶剂反应生成3-乙酰基-8-甲氧基- 2h -铬-2- 1 (C)，化合物C用CuBr2进行α-溴化，然后用硫脲环化得到3-(2-氨基噻唑-4-基)-8-甲氧基- 2h -铬-2- 1作为主支架(E)，该支架E最后与不同的氯化酸反应分离出标题化合物衍生物。通过1H-NMR、FT-IR和质谱/LCMS对合成化合物的化学结构进行了确证。对合成的化合物进行了潜在的抗菌、抗真菌和抗疟疾活性筛选。
{"title":"Synthesis and Bio-Evaluation of Novel N-(4-(8-Methoxy-2-Oxo-2H-Chromen-3-Yl) Thiazol-2-Yl) Amide Derivatives","authors":"Nilay Shah, P. N. Patel, D. Rajani, Denish C. Karia","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.71.19","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.71.19","url":null,"abstract":"In present work, novel derivatives of substituted N-(4-(8-methoxy-2-oxo-2H-chromen-3-yl) thiazol-2-yl) amide have been synthesized. The solvent free reaction of 2-Hydroxy-3-methoxybenzaldehyde with Ethyl acetoacetate in presence of Piperidine catalyst produces 3-acetyl-8-methoxy-2H-chromen-2-one (C). Compound C was α- brominated using CuBr2 and subsequently cyclized using Thiourea to produce 3-(2-aminothiazol-4-yl)-8-methoxy-2H-chromen-2-one as main scaffold (E). This scaffold E was finally reacted with different Acid chloride to isolate title compound derivatives. The chemical structures of synthesized compounds were confirmed by 1H-NMR, FT-IR and Mass spectral/LCMS analysis. The synthesized compounds were screened for potential Antimicrobial, Antifungal and Antimalarial activity.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"256 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72975106","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 : 2016-11-01DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.71.1
J. Sailaja, N. Murali, K. Samatha, V. Veeraiah
This paper reports on the effect of Strontium doping on BaCe0.7Zr0.3O3 electrolyte prepared using the citrate-EDTA complexing sol-gel process at temperature T=1000°C. The phase formation and evolution with the temperature has been studied by X-ray diffraction (XRD), thermal analysis (TG-DTA).The morphology of the sintered powder at T=1300°C are examined by SEM - Scanning Electron MicroscopyEDAX - Energy-dispersive X-ray spectroscopy analysisFTIR - Fourier transforms infrared spectrometer FTRS-Raman measurementsThe crystallite size of the ceramic powders calculated from Scherrer equation is 28nm and the diffraction peak shifted to higher angles. Microstructure of the sintered powder revealed that the average grain size is in the range of 2mm. The incorporation of Sr is found to suppress the formation of CeO2 like second phase and enhance the grain growth in sintered oxides. Dense ceramic materials were obtained at 1300°C and the relative density is 80% of the theoretical density. FTIR and Raman measurements reveal the complete single phase formation of the orthorhombic perovskite structure. The ionic conductivity of the pellet is investigated from room temperature to 400°C and is found to be 1.1x10-4S/cm (400°C). The conductivity increased as temperature increases and the activation energies is 0.48eV and hence this composition qualifies to be a promising electrolyte.
{"title":"Synthesis and Characterization of Ba0.96Sr0.04Ce0.7Zr0.3O3 Solid Oxide Fuel Cell Electrolyte by Citrate EDTA Complexing Sol-Gel Process","authors":"J. Sailaja, N. Murali, K. Samatha, V. Veeraiah","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.71.1","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.71.1","url":null,"abstract":"This paper reports on the effect of Strontium doping on BaCe0.7Zr0.3O3 electrolyte prepared using the citrate-EDTA complexing sol-gel process at temperature T=1000°C. The phase formation and evolution with the temperature has been studied by X-ray diffraction (XRD), thermal analysis (TG-DTA).The morphology of the sintered powder at T=1300°C are examined by SEM - Scanning Electron MicroscopyEDAX - Energy-dispersive X-ray spectroscopy analysisFTIR - Fourier transforms infrared spectrometer FTRS-Raman measurementsThe crystallite size of the ceramic powders calculated from Scherrer equation is 28nm and the diffraction peak shifted to higher angles. Microstructure of the sintered powder revealed that the average grain size is in the range of 2mm. The incorporation of Sr is found to suppress the formation of CeO2 like second phase and enhance the grain growth in sintered oxides. Dense ceramic materials were obtained at 1300°C and the relative density is 80% of the theoretical density. FTIR and Raman measurements reveal the complete single phase formation of the orthorhombic perovskite structure. The ionic conductivity of the pellet is investigated from room temperature to 400°C and is found to be 1.1x10-4S/cm (400°C). The conductivity increased as temperature increases and the activation energies is 0.48eV and hence this composition qualifies to be a promising electrolyte.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72785898","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 : 2016-11-01DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.71.40
Madhavi Karanam, G. M. Rao, S. Habibuddin, R. Padmasuvarna
Porous Silicon (PSi) is synthesized by Ag assisted electroless etching and characterized by Scanning electron microscopy (SEM). The effect of etching time on the optical reflectivity, optical absorbance of PSi is investigated. Reflectivity measurements showed that 45% reflectivity Si wafers drops from 45% to 10% for 2 hours etching and 6% for 3 hours etching. The decrease in the reflectivity shows that the PSi can be employed as an anti reflecting substrate in optoelectronic devices. The absorbance measurements reveal that the average absorbance of PSi is 0.60 in the wavelength range 300-800 nm after 2 hours etching. From the photoluminescence spectra it was found that PL intensity of PSi is high compared to bare silicon wafer. Static water contact angle measurements were performed to examine the hydrophobic properties of the PSi prepared under different conditions.
{"title":"Study of the Properties of the Porous Silicon Synthesized by Ag Assisted Chemical Etching","authors":"Madhavi Karanam, G. M. Rao, S. Habibuddin, R. Padmasuvarna","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.71.40","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.71.40","url":null,"abstract":"Porous Silicon (PSi) is synthesized by Ag assisted electroless etching and characterized by Scanning electron microscopy (SEM). The effect of etching time on the optical reflectivity, optical absorbance of PSi is investigated. Reflectivity measurements showed that 45% reflectivity Si wafers drops from 45% to 10% for 2 hours etching and 6% for 3 hours etching. The decrease in the reflectivity shows that the PSi can be employed as an anti reflecting substrate in optoelectronic devices. The absorbance measurements reveal that the average absorbance of PSi is 0.60 in the wavelength range 300-800 nm after 2 hours etching. From the photoluminescence spectra it was found that PL intensity of PSi is high compared to bare silicon wafer. Static water contact angle measurements were performed to examine the hydrophobic properties of the PSi prepared under different conditions.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86554645","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 : 2016-11-01DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.71.11
O. L. Adebayo, A. A. Adaramodu, M. G. Ajayi, F. E. Olasehinde, J. Oyetunde
The adsorption capacity of Palmkernel shell (PKS) which was used as an adsorbent in this study were boosted by acid thermoactivation. The nitrate sorption potential, point zero charge (PZC) and surface area of the PKS were enhanced by the acid thermoactivation process. The process of sorption of nitrate from solution was analyzed using five different isotherm models [Langmuir, Freundlich, Temkin, Harkins-Jura, and Halsey isotherm equations]. The value of the Langmuir monolayer sorption capacity qm [mg/g] increased from 60.12 to 85.73, PZC values increased from 5.50 to 8.40, and the surface area [m2/g] value increased from 29 m2/g to 98 m2/g after the activation process. The effect of pH on the sorption of the nitrate on both sorbents was also considered and it was discovered that the adsorption of nitrate decreases with increase in nitrate solution pH. The effects of the sorbents dose on the sorption process was also studied and the results showed that the amount of nitrate sorbed by both sorbent decreases with increase in sorbent dose.
{"title":"Purification of Nitrate Contaminated Aqueous Solution Using Modified and Unmodified Palmkernel Shell","authors":"O. L. Adebayo, A. A. Adaramodu, M. G. Ajayi, F. E. Olasehinde, J. Oyetunde","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.71.11","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.71.11","url":null,"abstract":"The adsorption capacity of Palmkernel shell (PKS) which was used as an adsorbent in this study were boosted by acid thermoactivation. The nitrate sorption potential, point zero charge (PZC) and surface area of the PKS were enhanced by the acid thermoactivation process. The process of sorption of nitrate from solution was analyzed using five different isotherm models [Langmuir, Freundlich, Temkin, Harkins-Jura, and Halsey isotherm equations]. The value of the Langmuir monolayer sorption capacity qm [mg/g] increased from 60.12 to 85.73, PZC values increased from 5.50 to 8.40, and the surface area [m2/g] value increased from 29 m2/g to 98 m2/g after the activation process. The effect of pH on the sorption of the nitrate on both sorbents was also considered and it was discovered that the adsorption of nitrate decreases with increase in nitrate solution pH. The effects of the sorbents dose on the sorption process was also studied and the results showed that the amount of nitrate sorbed by both sorbent decreases with increase in sorbent dose.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"103 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81759882","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 : 2016-11-01DOI: 10.18052/WWW.SCIPRESS.COM/ILCPA.71.29
Mouhammed Khateeb, Bashir Elias, Shahama Adi
A new, simple and sensitive kinetic spectrophotometric method has been proposed for the determination of captopril (CPT) in pharmaceutical formulations. The method is based on oxidation of 3-methyl-2-benzothiazolinone hydrazone hydrochloride monohydrate (MBTH) by ferric chloride followed by its coupling with the drug to form green-yellow colored product with absorbance maximum at 395nm. The concentration of CPT was calculated using the calibration equation for the rate data and fixed time methods. The linearity range was found to be 0.5–22.5 μg mL-1 for each method. The correlation coefficients were 0.9994 and 0.9971 for rate data and fixed time methods respectively. The proposed methods were applied successfully for the determination of CPT in pharmaceutical formulations. Statistical comparison of the results shows that there is no significant difference between the proposed and official methods.
{"title":"A Novel Use of 3-Methyl-2-Benzothiazolinone Hydrazone Hydrochloride Monohydrate for Kinetic Spectrophotometric Determination of Captopril in Pharmaceutical Formulations","authors":"Mouhammed Khateeb, Bashir Elias, Shahama Adi","doi":"10.18052/WWW.SCIPRESS.COM/ILCPA.71.29","DOIUrl":"https://doi.org/10.18052/WWW.SCIPRESS.COM/ILCPA.71.29","url":null,"abstract":"A new, simple and sensitive kinetic spectrophotometric method has been proposed for the determination of captopril (CPT) in pharmaceutical formulations. The method is based on oxidation of 3-methyl-2-benzothiazolinone hydrazone hydrochloride monohydrate (MBTH) by ferric chloride followed by its coupling with the drug to form green-yellow colored product with absorbance maximum at 395nm. The concentration of CPT was calculated using the calibration equation for the rate data and fixed time methods. The linearity range was found to be 0.5–22.5 μg mL-1 for each method. The correlation coefficients were 0.9994 and 0.9971 for rate data and fixed time methods respectively. The proposed methods were applied successfully for the determination of CPT in pharmaceutical formulations. Statistical comparison of the results shows that there is no significant difference between the proposed and official methods.","PeriodicalId":14453,"journal":{"name":"International Letters of Chemistry, Physics and Astronomy","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82904386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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