O. A. Babatunde, A. P. Olufemi, L. Sunmonu, O. E. Abiye, O. R. Omokungbe, A. B. Toyeje, O. E. Obisesan
An experimental site at Obafemi Awolowo University's Teaching and Research Farm, in Ile-Ife, Nigeria, was used to conduct multilevel measurements of meteorological parameters, and turbulent fluxes of sensible and latent heat in the atmospheric surface layer (ASL) between June 1 and July 31, 2016. The framework provided by Monin-Obukhov Similarity Theory (MOST) for estimating the turbulent fluxes of sensible and latent heat through existing empirical flux-profile relationships was employed. The objective of this study was to evaluate the performance of the flux-profile technique based on direct measurements of turbulent fluxes obtained from an eddy covariance (EC) system set up at the same location. The results showed that the diurnal patterns of both sensible and latent heat fluxes estimated from flux-profile technique compared relatively well with the direct measurements of the EC system. Nighttime estimations under stably stratified conditions of the atmosphere strongly correlated (R = 0.98) with the directly measured values. However, during the daytime convective conditions, there were some consistent discrepancies in the performance of the flux-profile technique with errors in some of the estimated fluxes well within the uncertainty range of the EC measurements. For sensible heat flux estimates; the coefficient of determination, R2 (0.71), the mean biased error, MBE (15.1 W/m2) and the percentage error determined for the period averaged values of the daytime estimates indicated that the sensible heat flux was only overestimated by up to 20%. On the other hand, a negative MBE 2 2 (-28.2 W/m2), weak coefficient of determination, R2(0.58)and negative percentage error obtained for the period averaged values of the latent heat flux indicated there is an underestimation of up to 45%. It can be concluded the flux-profile relationships can be employed within certain limits of confidence interval at tropical locations especially for the estimation of sensible heat flux.
{"title":"Determination of near-surface turbulent fluxes at a tropical location: an evaluation of flux-profile technique","authors":"O. A. Babatunde, A. P. Olufemi, L. Sunmonu, O. E. Abiye, O. R. Omokungbe, A. B. Toyeje, O. E. Obisesan","doi":"10.4314/ijs.v25i3.13","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.13","url":null,"abstract":"An experimental site at Obafemi Awolowo University's Teaching and Research Farm, in Ile-Ife, Nigeria, was used to conduct multilevel measurements of meteorological parameters, and turbulent fluxes of sensible and latent heat in the atmospheric surface layer (ASL) between June 1 and July 31, 2016. The framework provided by Monin-Obukhov Similarity Theory (MOST) for estimating the turbulent fluxes of sensible and latent heat through existing empirical flux-profile relationships was employed. The objective of this study was to evaluate the performance of the flux-profile technique based on direct measurements of turbulent fluxes obtained from an eddy covariance (EC) system set up at the same location. The results showed that the diurnal patterns of both sensible and latent heat fluxes estimated from flux-profile technique compared relatively well with the direct measurements of the EC system. Nighttime estimations under stably stratified conditions of the atmosphere strongly correlated (R = 0.98) with the directly measured values. However, during the daytime convective conditions, there were some consistent discrepancies in the performance of the flux-profile technique with errors in some of the estimated fluxes well within the uncertainty range of the EC measurements. For sensible heat flux estimates; the coefficient of determination, R2 (0.71), the mean biased error, MBE (15.1 W/m2) and the percentage error determined for the period averaged values of the daytime estimates indicated that the sensible heat flux was only overestimated by up to 20%. On the other hand, a negative MBE 2 2 (-28.2 W/m2), weak coefficient of determination, R2(0.58)and negative percentage error obtained for the period averaged values of the latent heat flux indicated there is an underestimation of up to 45%. It can be concluded the flux-profile relationships can be employed within certain limits of confidence interval at tropical locations especially for the estimation of sensible heat flux.","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"32 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448516","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}
O. Afolabi, B. M. Salami, T.M. Olapade, O. A. Alao
Geophysical and the geotechnical methods were used to study the site of a collapsed two-storey building in orderto determine the sequence and competence of the subsurface layers and determine the cause of the collapse of the building. The geophysical method employed the electrical resistivity method involving one dimensional (1D) Vertical Electrical Sounding (VES) and the two dimensional (2D) imaging techniques. Three VES stations were occupied using Schlumberger electrode configuration. 2D imaging data were acquired along four traverses using dipole-dipole electrode configuration. The geotechnical method involved Cone Penetration Test (CPT). CPT data was acquired at two points with the aid of 2.5 ton Dutch CPT machine. The results showed four subsurface layers based on the 1D VES results and 2D imaging results namely: topsoil, weathered layer, fractured basement rock and fresh basement rock. The topsoil resistivity varied from 116 Ωm to 191 Ωm and has thickness of about 1.5 m. It was classified as moderately competent. The second layer is weathered rock with resistivity varying between 92 Ωm and 327 Ωm and of about 8 m to 13 m thickness. This layer is also moderately competent. The third layer is fractured basement rock. It underlies the weathered rock and have resistivity varying from 391 Ωm to 405 Ωm. Its thickness varied from about 2 m to 20 m. This layer is competent. The fourth layer is the fresh basement rock having resistivity varying from 1365 Ωm to 12348 Ωm and is highly competent. The subsurface materials in the area are competent and can sustain the foundation of the building. Hence, the study concluded that the building collapse did not result from incompetent subsurface materials. Factors other than incompetent subsoil material that is human factors are believed to be responsible. This study has demonstrated the effectiveness of geophysical and geotechnical investigations in determining the competence of subsurface materials at engineering sites.
{"title":"Geophysical and geotechnical investigations of the site of a collapsed two-storey building in Modomo, Ile-Ife, Southwestern Nigeria","authors":"O. Afolabi, B. M. Salami, T.M. Olapade, O. A. Alao","doi":"10.4314/ijs.v25i3.11","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.11","url":null,"abstract":"Geophysical and the geotechnical methods were used to study the site of a collapsed two-storey building in orderto determine the sequence and competence of the subsurface layers and determine the cause of the collapse of the building. The geophysical method employed the electrical resistivity method involving one dimensional (1D) Vertical Electrical Sounding (VES) and the two dimensional (2D) imaging techniques. Three VES stations were occupied using Schlumberger electrode configuration. 2D imaging data were acquired along four traverses using dipole-dipole electrode configuration. The geotechnical method involved Cone Penetration Test (CPT). CPT data was acquired at two points with the aid of 2.5 ton Dutch CPT machine. The results showed four subsurface layers based on the 1D VES results and 2D imaging results namely: topsoil, weathered layer, fractured basement rock and fresh basement rock. The topsoil resistivity varied from 116 Ωm to 191 Ωm and has thickness of about 1.5 m. It was classified as moderately competent. The second layer is weathered rock with resistivity varying between 92 Ωm and 327 Ωm and of about 8 m to 13 m thickness. This layer is also moderately competent. The third layer is fractured basement rock. It underlies the weathered rock and have resistivity varying from 391 Ωm to 405 Ωm. Its thickness varied from about 2 m to 20 m. This layer is competent. The fourth layer is the fresh basement rock having resistivity varying from 1365 Ωm to 12348 Ωm and is highly competent. The subsurface materials in the area are competent and can sustain the foundation of the building. Hence, the study concluded that the building collapse did not result from incompetent subsurface materials. Factors other than incompetent subsoil material that is human factors are believed to be responsible. This study has demonstrated the effectiveness of geophysical and geotechnical investigations in determining the competence of subsurface materials at engineering sites. ","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"14 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448673","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}
E. J. Oziegbe, O. O. Ocan, A. Adetunji, O. Oziegbe
Petrography, mineral chemistry and whole rock analyses were conducted on a metabasite dyke hosted by pelitic gneiss (metapelite) in Ogbagi Akoko area with the aim of determining its metamorphic evolution. The dyke is about 40 cm wide and traceable for some meters along strike. It has a discordant contact relationship that is pencil sharp with the host pelitic gneiss and lack any internal fabric. The mineral assemblage includes: garnet +biotite + plagioclase + quartz + orthopyroxene + K-feldspar + ilmenite, with apatite occurring as an accessory mineral. Plagioclase has anorthite content of about 76 (An76) suggesting bytownite (An76 Ab24 Or0) while garnets are poikiloblastic almandine-pyrope rich with XFe of 0.73-0.75. Orthopyroxene has a composition of Wo0 En50 Fs50 suggesting hypersthene that is depleted in Ca. The mineral assemblage, presence of bytownite, absence of amphibole and lack of internal fabric indicate that the rock has undergone metamorphism at a high temperature and moderate pressure without deformation at granulite facies metamorphism. The absence of deformation structure in the dyke is an indication that the intrusion occurred after the cessation of the regional metamorphism but prevalent high temperature that recrystallized the rock. The whole rock composition and some elemental ratios of the dyke indicate that the metamorphism had little or no effect on the bulk chemistry of the rock.
{"title":"Metamorphic evolution of a metabasite dyke from Ogbagi Akoko area, Southwestern Nigeria","authors":"E. J. Oziegbe, O. O. Ocan, A. Adetunji, O. Oziegbe","doi":"10.4314/ijs.v25i3.5","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.5","url":null,"abstract":"Petrography, mineral chemistry and whole rock analyses were conducted on a metabasite dyke hosted by pelitic gneiss (metapelite) in Ogbagi Akoko area with the aim of determining its metamorphic evolution. The dyke is about 40 cm wide and traceable for some meters along strike. It has a discordant contact relationship that is pencil sharp with the host pelitic gneiss and lack any internal fabric. The mineral assemblage includes: garnet +biotite + plagioclase + quartz + orthopyroxene + K-feldspar + ilmenite, with apatite occurring as an accessory mineral. Plagioclase has anorthite content of about 76 (An76) suggesting bytownite (An76 Ab24 Or0) while garnets are poikiloblastic almandine-pyrope rich with XFe of 0.73-0.75. Orthopyroxene has a composition of Wo0 En50 Fs50 suggesting hypersthene that is depleted in Ca. The mineral assemblage, presence of bytownite, absence of amphibole and lack of internal fabric indicate that the rock has undergone metamorphism at a high temperature and moderate pressure without deformation at granulite facies metamorphism. The absence of deformation structure in the dyke is an indication that the intrusion occurred after the cessation of the regional metamorphism but prevalent high temperature that recrystallized the rock. The whole rock composition and some elemental ratios of the dyke indicate that the metamorphism had little or no effect on the bulk chemistry of the rock.","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448811","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}
Grains are exposed to contamination by mycotoxins, both in the field and during storage. Aflatoxins produced by Aspergillus species are the most harmful and carcinogenic mycotoxins in grains. Synthetic fungicides are widely used for the control of mycotoxigenic fungi in grains. However, rising public awareness about the toxicological effects of fungicides on human health necessitates the development of non-toxic bio-fungicides. In this connection, reports have shown that chitosan synthesized from shell waste has the potential to serve as an alternative fungicide. Therefore, this study investigated the fungicidal efficacy of free and nano-encapsulated chitosan against aflatoxigenic fungus (Aspergillus flavus). High molecular weight chitosan was purchased, and the in-vitro antifungal efficacy of chitosan against A. flavus was tested using the food poisoning method. Nano-encapsulated chitosan was synthesized using the ionic gelation method, the particle size was determined, and invitro inhibition against A. flavus was investigated. The results revealed that nano-encapsulated chitosan with particle sizes of 525.4 nm, 468.3 nm, and 711.7 nm were obtained. In-vitro mycelial A. flavus growth inhibition of 100% was recorded at 1.5% and 2.0% of free chitosan, while at 0.5% and 1.0% of free chitosan, 45% and 75% inhibition were observed, respectively. Nano-encapsulated chitosan with particle size (nm) of 525.4, 468.3, and 711.7 at 0.50% recorded 61%, 84% and 87% inhibition, respectively. However, at 0.25%, the rate of inhibition was 64%, 78% and 67%, respectively. This study showed that free chitosan and nano-encapsulated chitosan are potential antifungal agents for the control of A. flavus.
{"title":"Evaluation of fungicidal efficacy of free and nano-encapsulated chitosan against Aspergillus flavus isolated from rice (Oryza sativa) seed","authors":"M. Aremu, M. Adebola, C. E. Egwim, M. Salaudeen","doi":"10.4314/ijs.v25i3.3","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.3","url":null,"abstract":"Grains are exposed to contamination by mycotoxins, both in the field and during storage. Aflatoxins produced by Aspergillus species are the most harmful and carcinogenic mycotoxins in grains. Synthetic fungicides are widely used for the control of mycotoxigenic fungi in grains. However, rising public awareness about the toxicological effects of fungicides on human health necessitates the development of non-toxic bio-fungicides. In this connection, reports have shown that chitosan synthesized from shell waste has the potential to serve as an alternative fungicide. Therefore, this study investigated the fungicidal efficacy of free and nano-encapsulated chitosan against aflatoxigenic fungus (Aspergillus flavus). High molecular weight chitosan was purchased, and the in-vitro antifungal efficacy of chitosan against A. flavus was tested using the food poisoning method. Nano-encapsulated chitosan was synthesized using the ionic gelation method, the particle size was determined, and invitro inhibition against A. flavus was investigated. The results revealed that nano-encapsulated chitosan with particle sizes of 525.4 nm, 468.3 nm, and 711.7 nm were obtained. In-vitro mycelial A. flavus growth inhibition of 100% was recorded at 1.5% and 2.0% of free chitosan, while at 0.5% and 1.0% of free chitosan, 45% and 75% inhibition were observed, respectively. Nano-encapsulated chitosan with particle size (nm) of 525.4, 468.3, and 711.7 at 0.50% recorded 61%, 84% and 87% inhibition, respectively. However, at 0.25%, the rate of inhibition was 64%, 78% and 67%, respectively. This study showed that free chitosan and nano-encapsulated chitosan are potential antifungal agents for the control of A. flavus.","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"23 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448722","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. I. Obasi, G.O. Aigbadon, F. Chinyem, C.N. Chukwu, J. B. Ahmed II, S.O. Abubakar, F.D. Attah, E. O. Akudo
The parameters of the aquifers in Idah area were characterized by integrating resistivity and litholog data. To achieve this, a total of twenty-three (23) Soundings were conducted by applying the 1-D Schlumberger resistivity array and integrating it with borehole lithologs to empirically determine the aquifer parameters in the Idah area, Northern Anambra Basin, Nigeria. The results of the analyses indicate that the aquifer zone resistivity ranges from 36.65 – 2065.31 Ωm while the aquifer thickness is between 15.60 m and 66.66 m. Its values of the longitudinal conductance (S), transverse resistance (TR), and hydraulic conductivity (k) are 0.01-1.13 mhos, 1518.90-90265.88 Ωm2 , and 0.31-13.44 m/day, respectively. The transmissivity (T) values vary from 4.88 to 2 557.78 m /day. T is inversely proportional to TR with a correlation coefficient of 0.28. The result of the reflection coefficient is in the range of -0.79 to 0.66, while that of the fractured contrast is between 0.11 and 5.06. The results suggest that an aquifer system that is predominantly fracture-based is underlying the region. Lithification and diagenesis influence the hydrological properties. The northern–central portions of the map are more suitable for groundwater exploration /exploitation than the southern/eastern ends.
{"title":"Estimation of aquifer parameters from electrical resistivity data and lithologs in Idah area, Northern Anambra basin, Nigeria","authors":"A. I. Obasi, G.O. Aigbadon, F. Chinyem, C.N. Chukwu, J. B. Ahmed II, S.O. Abubakar, F.D. Attah, E. O. Akudo","doi":"10.4314/ijs.v25i3.10","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.10","url":null,"abstract":"The parameters of the aquifers in Idah area were characterized by integrating resistivity and litholog data. To achieve this, a total of twenty-three (23) Soundings were conducted by applying the 1-D Schlumberger resistivity array and integrating it with borehole lithologs to empirically determine the aquifer parameters in the Idah area, Northern Anambra Basin, Nigeria. The results of the analyses indicate that the aquifer zone resistivity ranges from 36.65 – 2065.31 Ωm while the aquifer thickness is between 15.60 m and 66.66 m. Its values of the longitudinal conductance (S), transverse resistance (TR), and hydraulic conductivity (k) are 0.01-1.13 mhos, 1518.90-90265.88 Ωm2 , and 0.31-13.44 m/day, respectively. The transmissivity (T) values vary from 4.88 to 2 557.78 m /day. T is inversely proportional to TR with a correlation coefficient of 0.28. The result of the reflection coefficient is in the range of -0.79 to 0.66, while that of the fractured contrast is between 0.11 and 5.06. The results suggest that an aquifer system that is predominantly fracture-based is underlying the region. Lithification and diagenesis influence the hydrological properties. The northern–central portions of the map are more suitable for groundwater exploration /exploitation than the southern/eastern ends. ","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"10 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448789","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}
T. A. Ajayeoba, A.T. Famojuro, E. Akinkunmi, O. Olasehinde, A. O. Ayeni, O. Akinyele, J.A.O. Woods
Three new ligands viz, benzylacetone-enzoylhydrazone [babh (L1)], para-hydroxy-benzylacetone-benzoylhydrazone [p-OH-babh (L2 )] and para-nitrobenzylacetone-benzoylhydrazone [p-NO2 -babh (L3 )], were synthesised by condensation of hydrazides with benzylacetone. The ligands were each reacted with copper(II) salts (chloride, nitrate, acetate and sulphate) to form complexes with the general formulae ML2X2 (X = Cl , NO3 , AcO- and SO4 ). The compounds were characterised using 1H NMR, Infrared and UV-Visible spectroscopy, as 4 well as CHN elemental analyser and magnetic susceptibility measurements. Antibacterial activity of the ligands and synthesised complexes were investigated using the agar diffusion method against two Gram-positive (Staphylococcus aureus NCTC 6571 and Bacillus cereus ATCC 11778) and three Gram- negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 10145, Klebsiella pneumonia ATCC 13048) bacterial strains. However, the observed antimicrobial strength of the synthesized compounds was rather low.
{"title":"Synthesis, characterisation and antibacterial study of copper(ii) complexes of new benzylacetone-benzoylhydrazone and its para-nitro and para-hydroxy substituted analogues","authors":"T. A. Ajayeoba, A.T. Famojuro, E. Akinkunmi, O. Olasehinde, A. O. Ayeni, O. Akinyele, J.A.O. Woods","doi":"10.4314/ijs.v25i3.17","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.17","url":null,"abstract":"Three new ligands viz, benzylacetone-enzoylhydrazone [babh (L1)], para-hydroxy-benzylacetone-benzoylhydrazone [p-OH-babh (L2 )] and para-nitrobenzylacetone-benzoylhydrazone [p-NO2 -babh (L3 )], were synthesised by condensation of hydrazides with benzylacetone. The ligands were each reacted with copper(II) salts (chloride, nitrate, acetate and sulphate) to form complexes with the general formulae ML2X2 (X = Cl , NO3 , AcO- and SO4 ). The compounds were characterised using 1H NMR, Infrared and UV-Visible spectroscopy, as 4 well as CHN elemental analyser and magnetic susceptibility measurements. Antibacterial activity of the ligands and synthesised complexes were investigated using the agar diffusion method against two Gram-positive (Staphylococcus aureus NCTC 6571 and Bacillus cereus ATCC 11778) and three Gram- negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 10145, Klebsiella pneumonia ATCC 13048) bacterial strains. However, the observed antimicrobial strength of the synthesized compounds was rather low.","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"67 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study seeks to compare the application of activated snail and periwinkle shells in the removal of heavy metal ions from aqueous solution. Snail and periwinkle shells obtained from local markets in Warri, Nigeria, were carbonized, activated and characterized. Batch adsorption experiment was carried out to determine the effect of pH, concentration, adsorbent dose and contact time on the adsorption process. Data obtained were examined using adsorption isotherms. Characterization result showed that activated carbon obtained from periwinkle shells had higher values of pH, pore volume, moisture content and porosity than the values obtained for activated snail shells. The maximum pH obtained for the adsorption of Pb2+ and Cd2+ ions using activated periwinkle shell carbon (APSC) and activated snail shell carbon (ASSC) were 7 for Pb2+ and 4 – 10 for Cd 2+ . The percentage adsorption of these ions onto APSC were 96.70% Pb2+ and 100% Cd2+ while that of ASSC were 95.00% Pb+2 and 68.80% Cd2+ . The optimum adsorbent dose and contact time for the removal of these ions, using both adsorbents, were 3 g and 90 min, respectively. Results revealed that APSC had better adsorption capacity than ASSC for most parameters studied. Of the four adsorption isotherms models used for this study, Langmuir had the highest regression coefficient (R2 = 0.9852 for APSC and 0.8950 for ASSC). Data for adsorption kinetics exhibited a good compliance with pseudo-second order kinetic model
{"title":"Comparative studies on the use of activated snail (Achanita fulica) and periwinkle shells (Typanotonus fuscatu) in the removal of heavy metal ions from aqueous solutions","authors":"B. A. Nwajei, J. N. Jacob, J. Okuo","doi":"10.4314/ijs.v25i3.1","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.1","url":null,"abstract":"This study seeks to compare the application of activated snail and periwinkle shells in the removal of heavy metal ions from aqueous solution. Snail and periwinkle shells obtained from local markets in Warri, Nigeria, were carbonized, activated and characterized. Batch adsorption experiment was carried out to determine the effect of pH, concentration, adsorbent dose and contact time on the adsorption process. Data obtained were examined using adsorption isotherms. Characterization result showed that activated carbon obtained from periwinkle shells had higher values of pH, pore volume, moisture content and porosity than the values obtained for activated snail shells. The maximum pH obtained for the adsorption of Pb2+ and Cd2+ ions using activated periwinkle shell carbon (APSC) and activated snail shell carbon (ASSC) were 7 for Pb2+ and 4 – 10 for Cd 2+ . The percentage adsorption of these ions onto APSC were 96.70% Pb2+ and 100% Cd2+ while that of ASSC were 95.00% Pb+2 and 68.80% Cd2+ . The optimum adsorbent dose and contact time for the removal of these ions, using both adsorbents, were 3 g and 90 min, respectively. Results revealed that APSC had better adsorption capacity than ASSC for most parameters studied. Of the four adsorption isotherms models used for this study, Langmuir had the highest regression coefficient (R2 = 0.9852 for APSC and 0.8950 for ASSC). Data for adsorption kinetics exhibited a good compliance with pseudo-second order kinetic model","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"24 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448661","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}
Binomial system is a system of analysis which involves two chances or possible outcomes of event which are the extreme ends of such event. In real life, there exist the mid or intermediary chances or possible outcomes of some events, if not all events, making the possible outcomes of such events to be three. In any such scenario or instance of three possible outcomes, a trinomial system of analysis would be applicable. There is need to develop a model to analysis such scenarios of trinomial system. This research work presents real life applications of mathematical model of Kifilideen trinomial theorem distribution of positive powers of n with mathematical induction of negative powers of n counterpart. A mathematical model of the Kifilideen trinomial theorem distribution was formulated. This research work also develops alternate Kifilideen power combination formula, alternate Kifilideen term formula and alternate Kifilideen position formula for the negative powers of n, which conform but not the same, with the one developed for the positive powers of n counterpart. The formulated mathematical model of the Kifilideen trinomial theorem distribution was utilized to analysis real life events having three possible outcomes. The model invented in this paper can be used to determine the probability of the combination of different n outputs involving three possible categories of outcomes of events. The mathematical induction helps to support and prove that the developed Kifilideen formulas for the constituents of Kifilideen trinomial theorem of negative powers of n are valid and true.
二项式系统是一种分析系统，涉及事件的两种机会或可能结果，即事件的两端。在现实生活中，某些事件即使不是全部事件，也存在中间或中间机会或可能结果，这使得此类事件的可能结果为三种。在任何这种情况下或有三种可能结果的情况下，三叉分析系统都是适用的。有必要开发一个模型来分析三叉系统的这种情况。本研究工作介绍了 Kifilideen 三叉定理 n 的正幂分布数学模型在现实生活中的应用，以及 n 的负幂的对应数学归纳。建立了 Kifilideen 三叉定理分布的数学模型。这项研究工作还为 n 的负幂数建立了交替的 Kifilideen 幂组合公式、交替的 Kifilideen 项公式和交替的 Kifilideen 位置公式，它们与为 n 的正幂数建立的公式一致但不相同。所建立的基菲里登三叉定理分布数学模型被用来分析现实生活中可能出现三种结果的事件。本文发明的模型可用于确定涉及三种可能结果的事件的不同 n 种输出组合的概率。数学归纳法有助于支持和证明为负 n 次幂基菲里登三叉定理的组成成分所开发的基菲里登公式是有效和真实的。
{"title":"Real life applications of mathematical model of Kifilideen trinomial theorem distribution of positive powers of n with mathematical induction of the constituents of its negative powers of n counterpart","authors":"K. L. Osanyinpeju","doi":"10.4314/ijs.v25i3.7","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.7","url":null,"abstract":"Binomial system is a system of analysis which involves two chances or possible outcomes of event which are the extreme ends of such event. In real life, there exist the mid or intermediary chances or possible outcomes of some events, if not all events, making the possible outcomes of such events to be three. In any such scenario or instance of three possible outcomes, a trinomial system of analysis would be applicable. There is need to develop a model to analysis such scenarios of trinomial system. This research work presents real life applications of mathematical model of Kifilideen trinomial theorem distribution of positive powers of n with mathematical induction of negative powers of n counterpart. A mathematical model of the Kifilideen trinomial theorem distribution was formulated. This research work also develops alternate Kifilideen power combination formula, alternate Kifilideen term formula and alternate Kifilideen position formula for the negative powers of n, which conform but not the same, with the one developed for the positive powers of n counterpart. The formulated mathematical model of the Kifilideen trinomial theorem distribution was utilized to analysis real life events having three possible outcomes. The model invented in this paper can be used to determine the probability of the combination of different n outputs involving three possible categories of outcomes of events. The mathematical induction helps to support and prove that the developed Kifilideen formulas for the constituents of Kifilideen trinomial theorem of negative powers of n are valid and true.","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"29 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448691","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 rise in internet user demand is a major factor in the expansion of infrastructure and the upsurge in energy use in cloud, colocation, and some business data centres. The advent of 5G has compounded the situation, as it substantially gives room for many new types of digital services, resulting in a need for richer consume a lot of energy when no scaling method is applied. Services such as mail, data storage and retrieval and other cloud services also require a lot of high energy consumption which eventually result into carbon(IV) oxide (CO2) emissions to the environment. This research therefore, focuses on lowering the energy usage of a data centre with heterogeneous power awareness either in an idle server state or high-performance state using a novel hybridized algorithm called “DyVoFesLoReMu”, comprising Dynamic Voltage Frequency Scaling (Dvfs) and a modified Local Regression Minimum Utilization (LrMu). A real dataset (workload) obtained online from PlanetLab consisting of hosts and Virtual Machines (VM) was simulated on a data center in CloudSim 3.0.3. Tool kit with preset parameters consisting of VM Allocation Policy and VM Selection Policy was used. The tool kit was utilised to create cloud infrastructure and simulate the essential features of a cloud environment. The Cloudsim was installed on Eclipse Integrated Development Environment (IDE) 2019 version on Windows 10 operating system. The hybridized algorithm was compared with other five (5) existing energy reducing algorithms and it was found to be more efficient with a range of 41-90% reduction in energy usage from the ten days workload traces and in comparison with the existing algorithms used for the simulation.
{"title":"An efficient reducing mechanism for energy consumption in data center using hybrid consolidation techniques","authors":"E. O. Oyekanmi, O.M. Adegoke","doi":"10.4314/ijs.v25i3.8","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.8","url":null,"abstract":"The rise in internet user demand is a major factor in the expansion of infrastructure and the upsurge in energy use in cloud, colocation, and some business data centres. The advent of 5G has compounded the situation, as it substantially gives room for many new types of digital services, resulting in a need for richer consume a lot of energy when no scaling method is applied. Services such as mail, data storage and retrieval and other cloud services also require a lot of high energy consumption which eventually result into carbon(IV) oxide (CO2) emissions to the environment. This research therefore, focuses on lowering the energy usage of a data centre with heterogeneous power awareness either in an idle server state or high-performance state using a novel hybridized algorithm called “DyVoFesLoReMu”, comprising Dynamic Voltage Frequency Scaling (Dvfs) and a modified Local Regression Minimum Utilization (LrMu). A real dataset (workload) obtained online from PlanetLab consisting of hosts and Virtual Machines (VM) was simulated on a data center in CloudSim 3.0.3. Tool kit with preset parameters consisting of VM Allocation Policy and VM Selection Policy was used. The tool kit was utilised to create cloud infrastructure and simulate the essential features of a cloud environment. The Cloudsim was installed on Eclipse Integrated Development Environment (IDE) 2019 version on Windows 10 operating system. The hybridized algorithm was compared with other five (5) existing energy reducing algorithms and it was found to be more efficient with a range of 41-90% reduction in energy usage from the ten days workload traces and in comparison with the existing algorithms used for the simulation. ","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"67 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139449232","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}
Soil washing is an effective method of removing lead from contaminated soils. However, great limitations abound in the choice of washing solution that is ecologically sustainable for agricultural soils. In this study, applications of plant soluble extracts in remediating of Pb contaminated soils for ecological sustainability were carried out. Batch laboratory experiments were done using aqueous extracts of Alternanthera brasiliana, Chromolaena odorata, Tridax procumbens and water as control at varying soil-pulp-densities (SPD) of 3, 6, 9, 12, 15%, and washing time of 1, 3, 6, 12 h. For contaminated soil, percentage removal efficiency followed the order: Alternanthera brasiliana (38.1±0.28%) > Chromolaena odorata (21.8±0.12%) > Tridax procumbens (21.3±0.18%). The most appropriate ratio for contaminated soil was 3% SPD at 12 h washing time. Removal efficiency was found to be substantially depended on geochemical phase of Pb (exchangeable-4.04%) in contaminated soil and washing solution pH (5.68). Lead removal efficiency was observed to increased proportionally with increasing washing time, but decreased with increasing SPD. Spike soil with high exchangeable Pb-78.9% recorded significant Pb removal of 63.4±0.24% with Alternanthera brasiliana, 47.8±0.22% with Chromolaena odorata, 38.3±0.38% with Tridax procumbens and 52.0±0.26% with water. Analysis of variance at p=0.05 indicated a significant difference inpercentage Pb removal efficiency across all the four washing solutions. However, the statistical T-test indicated no significant difference at p=0.05 in percentage Pb removal efficiency between both soils. Also, moderately positive correlations were observed between contaminated and spiked soils for Alternanthera brasiliana (0.676), Chromolaena odorata (0.570) and Tridax procumbens (0.517) while negative correlation observed for water (0.485) which served as the control. The three plant extracts exhibited good potential characteristics as washing solutions for the treatment of Pb contaminated soils. Chemical modifications are recommended to enhance and improve their efficiencies when considering the geochemical phase of Pb in soil.
{"title":"Application of aqueous extracts of Alternanthera brasiliana, Chromolaena odorata and Tridax procumbens plants in remediating lead contaminated soils","authors":"E. U. Etim, A. E. Ayejuone","doi":"10.4314/ijs.v25i3.2","DOIUrl":"https://doi.org/10.4314/ijs.v25i3.2","url":null,"abstract":"Soil washing is an effective method of removing lead from contaminated soils. However, great limitations abound in the choice of washing solution that is ecologically sustainable for agricultural soils. In this study, applications of plant soluble extracts in remediating of Pb contaminated soils for ecological sustainability were carried out. Batch laboratory experiments were done using aqueous extracts of Alternanthera brasiliana, Chromolaena odorata, Tridax procumbens and water as control at varying soil-pulp-densities (SPD) of 3, 6, 9, 12, 15%, and washing time of 1, 3, 6, 12 h. For contaminated soil, percentage removal efficiency followed the order: Alternanthera brasiliana (38.1±0.28%) > Chromolaena odorata (21.8±0.12%) > Tridax procumbens (21.3±0.18%). The most appropriate ratio for contaminated soil was 3% SPD at 12 h washing time. Removal efficiency was found to be substantially depended on geochemical phase of Pb (exchangeable-4.04%) in contaminated soil and washing solution pH (5.68). Lead removal efficiency was observed to increased proportionally with increasing washing time, but decreased with increasing SPD. Spike soil with high exchangeable Pb-78.9% recorded significant Pb removal of 63.4±0.24% with Alternanthera brasiliana, 47.8±0.22% with Chromolaena odorata, 38.3±0.38% with Tridax procumbens and 52.0±0.26% with water. Analysis of variance at p=0.05 indicated a significant difference inpercentage Pb removal efficiency across all the four washing solutions. However, the statistical T-test indicated no significant difference at p=0.05 in percentage Pb removal efficiency between both soils. Also, moderately positive correlations were observed between contaminated and spiked soils for Alternanthera brasiliana (0.676), Chromolaena odorata (0.570) and Tridax procumbens (0.517) while negative correlation observed for water (0.485) which served as the control. The three plant extracts exhibited good potential characteristics as washing solutions for the treatment of Pb contaminated soils. Chemical modifications are recommended to enhance and improve their efficiencies when considering the geochemical phase of Pb in soil.","PeriodicalId":13487,"journal":{"name":"Ife Journal of Science","volume":"67 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139449237","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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