GSC biological and pharmaceutical sciences, Oct 29, 2023
The present work highlights the use of Ipomoea involucrate B. flower extract as a complexometric ... more The present work highlights the use of Ipomoea involucrate B. flower extract as a complexometric indicator in complex formation between the EDTA and the following metal solutions (Cu 2 , + Ba 2 , + Hg 2+ , Fe 3+ , and Bi 3+). Ipomoea involucrate is a species of the Ipomoea genus, belonging to the family Convolvulaceae. This natural indicator was extracted in 2M HCl at 100 0 C for 30-40 minutes, cooled and the extract filtered and extracted with ethyl acetate and the pigment extracted with amyl alcohol which was separated and concentrated over a water bath. The flower extract was screened for its use as an metallochromic indicator at different pHs in metal solutions of Cu 2 , + Ba 2 , + Hg 2+ , Fe 3+ , and Bi 3+ .This natural indicator from the results obtained gave sharp intense color change at the equivalence point of complex formation between the metals and the EDTA at both acidic and alkaline pHs in the metal solution of Cu 2+ and Fe 3+ and that with different amount of EDTA used in the titration, which increased as the pH value increased, while the ipomoea indicator gave sharp intense color change at the equivalence point of complex formation between the metals and the EDTA at alkaline pHs in the metal solution of Ba 2+ , Hg 2+ and Bi 3+ at pH > 10. Natural flower indicators could take the place of the synthetic metallochromic indicators currently used in conventional laboratories because these flower extracts have excellent performance with sharp and intense color change in end points during the complexometric titrations and simple, costeffective and environmentally friendly extraction methods.
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material of biological origin. The... more Wood is a heterogeneous, hygroscopic, cellular and anisotropic material of biological origin. The properties of wood that make it an ideal raw material for several purposes are mainly determined by the specific architecture of the cell walls. Moisture content, porosity and water imbitition capacity contribute to the quality of timber. The examination of the internal microscopic structure of the timber samples will be done by Scanning Electron Microscopy (SEM). Of the fifty-three timbers studied, thirty-two were of medium density (0.403 ± 0.020 to 0.715 ± 0.011 g/cm 3) , ten were of low density (0.256 ± 0.008 to 0.380 ± 0.012 g/cm 3) and eleven were quite dense (0.784 ± 0.020 to 1.111 ± 0.039 g/cm 3), with Ricinodendrom heudelotti having the least value and Irvinga smithii, the highest. Water imbibitions capacity after 24 hours was quite high for Ricinodendrom heudelotti and Ceiba pentandra while that for Irvinga smithii, Lophira lanceolate, Khaya senegalensis and Erythrophleum suaveolens were low. There was an inverse relationship between the maximum moisture content of these wood samples and their density. The scanning electron micrographs of selected timbers present ring-porous hardwoods as well as diffuse-poruos hardwoods.Fibrous nature of Entradrophragma utile and Hollarhena floribunda may account for their high moisture content (MC) values while the spherical granules in Tetrapluera tetraptera are suspected to be hydrophobic since the water imbibition capacity observed after 24h was lower than those of similar density.
Journal of Sustainable Bioenergy Systems, Dec 31, 2022
This work investigated and quantified the physicochemical, structural and morphological propertie... more This work investigated and quantified the physicochemical, structural and morphological properties of four (4) tropical timbers as precursor raw materials for possible utilization in the wood plastic industry. The physicochemical properties of the wood samples such as the bulk and tapped density, moisture content, water absorption capacity at 25˚C, volatile content, fixed carbon, ash content, alpha cellulose, hemicellulose, lignin, and extractives contents were determined using standard methods like the European Committee for Standardization and (CEN/TS) and the American Society for Testing Materials (ASTM) standards. The structural and morphological properties of the samples were examined with Fourier Infrared Transform (FTIR) spectroscopy and scanning electron microscope (SEM). Results indicated that the bulk density values of the timbers ranged from 0.34 g/cm 3 in Brachystegia eurycoma (W 3) to 0.47 g/cm 3 in Erythrophleum suaveolens (W 2), with the other timbers, Nuclea diderichii (W 1) and Prosopis africana (W 4) having the same bulk density of 0.40 g/cm 3. With respect to their moisture content, W 2 had the highest value (8.38%) while Nauclea diderrichii had the lowest value (6.52%). The water absorption capacities of the woods studied correlated with the cellulose composition of wood in the order of: W 3 > W 1 > W 4 > W 2. The FTIR results showed that W 2 and W 3 presented a slightly more prominent and broader band than the other woods at 1731 cm −1 , in agreement with the higher holocellulose content of these species, while W 2 and W 4 presented the most prominent peaks indicating higher lignin content than W 1 and W 3. The SEM micrographs of the wood flour samples investigated indicated that the surfaces of the woods were rough and heterogeneous with irregular crystal and
Organophosphorus esters fulfil many industrial, agricultural, and household roles. Nature has dep... more Organophosphorus esters fulfil many industrial, agricultural, and household roles. Nature has deployed phosphates and their related anhydrides as energy carriers and reservoirs, as constituents of genetic materials in the form of DNA and RNA, and as intermediates in key biochemical conversions. The transfer of the phosphoryl (PO3) group is thus a ubiquitous biological process that is involved in a variety of transformations at the cellular level such as bioenergy and signals transductions. Significant attention has been paid in the last seven decades to understanding the mechanisms of uncatalyzed (solution) chemistry of the phospho group transfer because of the notion that enzymes convert the dissociative transition state structures in the uncatalyzed reactions into associative ones in the biological processes. In this regard, it has also been proposed that the rate enhancements enacted by enzymes result from the desolvation of the ground state in the hydrophobic active site environ...
Recently, natural fibers have gained research attention in reinforcing polymers due to their avai... more Recently, natural fibers have gained research attention in reinforcing polymers due to their availability and unique properties in polymer applications. Preliminary studies indicate indiscriminate disposal of human hair (HH) and the burning of cow hair (CH) and sheep hair (SH) by abattoir operators in Nigeria; this has become a source of concern owing to the hazardous nature of these activities to human health and the environment. This study is, therefore, essential and seeks to utilize these waste materials in an environmentally sustainable way, as the hair fibers used in this work are renewable and will enhance the economy of any country if adequately utilized. The composites of Polypropylene (PP), human, sheep, and cow tail hair fibers were prepared at different weight percentage concentrations of 0, 2, 4, 6, and 8 w% using an injection molding machine. Untreated and treated PP composites were analyzed for average diameter, length, and density; the composites were also characterized for ultimate tensile strength, flexural strength, hardness, and impact strength. The average diameter assessment indicates viz: Cow tail hair > Human hair > Sheep hair. The sequence for hair fiber lengths shows that Sheep hair > Human hair > Cow hair, and the order for average density is Cow tail hair > Human hair > Sheep hair. The analysis of the mechanical properties of the reinforced and unreinforced PP composite showed that the Human hair/PP composite gave the best enhancement for ultimate tensile strength and modulus, flexural strength, and modulus at 8% fiber loading. Cow tail hair/PP composite yielded the best elongation at break at 2% fiber loading. Human hair/PP composite showed the best yield for impact strength at 4% fiber loading, while the Cow tail hair composite performed best for the hardness test at 2% fiber loading. The surface scanning electronic microscope (SEM) images showed no significant manufacturing defect on composites except for the air entrapment in the image of cow tail hair. The study also observed that there is no fiber breakage or void observed in the images. SEM images of the PP-composites interface at 8% maximum loading showed reasonably good fiber adhesion to the polymer matrix. This study is recommended for environmental sustainability and to improve material properties for various applications.
Polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are predominant pollutants linked ... more Polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are predominant pollutants linked with anthropogenic activities across a host of environmental mediums. The level of pollution, ecological and health risk were assessed in surface water from Ekulu in Enugu metropolis, Nigeria for 17 PAHs and selected HMs (As, Cd, Cr, Cu, Pb, Ni, Zn) components. PAHs and HMs were determined using a gas chromatography-flame ionization detector (GC-FID) and atomic adsorption spectrophotometer (AAS). The total PAHs in station A (3.17mg/l), B (1.51mg/l), and C (1.83mg/l) were due to high molecular weight (HMW) PAHs than low molecular weight (HMW) PAHs. HMs contents were within USEPA and WHO minimum contamination levels (MCL) except Cr and Pb. The molecular diagnostics of PAHs showed that incomplete combustion of carbonaceous compounds was dominant, while petrogenic was insignificant across all samples. The ecological indices of PAHs and HMs varied from medium to high pollution due to anthropo...
Current Research in Green and Sustainable Chemistry
There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement du... more There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement due to their toughness and light weight. In this research, low density polyethylene (LDPE) was reinforced using 0.25 M NaOH treated cow tail, human and sheep hair fibers at 2, 4, 6 and 8% concentration respectively prior to injection moulding. The average densities, diameters and lengths of hair fibres were assessed The results obtained from the analysis of reinforced LDPE composites indicated that cow tail hair gave the highest average density and diameter. Sheep hair had the highest length after grinding. The study also analyzed the ultimate tensile strength and modulus, flexural strength and modulus, elongation, impact and hardness test on the polymer and their composites as well as the morphology and statistical analysis of the composite. This study indicated that human hair LDPE composites achieved highest flexural strength, flexural modulus, ultimate tensile strength and tensile modulus at 8% fibre loading whereas elongation at break and hardness were at 4% fibre loading while impact strength was at 2%. The cow tail hair LDPE composite gave the best impact strength at 8% fibre loading and sheep hair at 6%. The SEM results showed no serious manufacturing defects on the composites. The analysis of variance indicated that only the means of the composites' flexural properties were statistically significant. This study shows that short animal hair fibres could be effectively used to reinforced LDPE, and therefore suggest an alternative waste management strategy of these natural fibres that are currently viewed as environmental nuisance in the study area.
Current Research in Green and Sustainable Chemistry, 2022
There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement du... more There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement due to their toughness and light weight. In this research, low density polyethylene (LDPE) was reinforced using 0.25 M NaOH treated cow tail, human and sheep hair fibers at 2, 4, 6 and 8% concentration respectively prior to injection moulding. The average densities, diameters and lengths of hair fibres were assessed The results obtained from the analysis of reinforced LDPE composites indicated that cow tail hair gave the highest average density and diameter. Sheep hair had the highest length after grinding. The study also analyzed the ultimate tensile strength and modulus, flexural strength and modulus, elongation, impact and hardness test on the polymer and their composites as well as the morphology and statistical analysis of the composite. This study indicated that human hair LDPE composites achieved highest flexural strength, flexural modulus, ultimate tensile strength and tensile modulus at 8% fibre loading whereas elongation at break and hardness were at 4% fibre loading while impact strength was at 2%. The cow tail hair LDPE composite gave the best impact strength at 8% fibre loading and sheep hair at 6%. The SEM results showed no serious manufacturing defects on the composites. The analysis of variance indicated that only the means of the composites' flexural properties were statistically significant. This study shows that short animal hair fibres could be effectively used to reinforced LDPE, and therefore suggest an alternative waste management strategy of these natural fibres that are currently viewed as environmental nuisance in the study area.
American Scientific Research Journal for Engineering, Technology, and Sciences, 2019
The purpose of this study is to reduce the flammability of Gmelina arborea using fire retardants.... more The purpose of this study is to reduce the flammability of Gmelina arborea using fire retardants. This becomes necessary because fire has caused a lot of devastating effect to mankind since its discovery. Gmelina arborea splints were immersed in different concentrations of antimony trichloride, ammonium sulphamate and mixture of the antimony trichloride and ammonium sulphamate to determine the ignition time (IT), flame propagation rate (FPR) and after-glow time (AGT). The results indicated reduction in flame propagation rate and after-glow time for the three flame retardants while ignition time was increased with increase in concentration for the retardants. It was also observed that the combined flame retardants gave the highest ignition time and least flame propagation rate and after-glow time among the three flame retardants used. These flame retardants can be used especially the mixture of antimony trichloride and ammonium sulphamate to hinder/slow the ignitability of Gmelina ar...
Journal of Petroleum Environmental Biotechnology, Feb 22, 2012
Different microbes (E.coli, Proteus, Klebsiella and Pseudomonas sp) were utilized in degradation ... more Different microbes (E.coli, Proteus, Klebsiella and Pseudomonas sp) were utilized in degradation of different hydrocarbon (Engine oil/diesel, kerosene and fuel) contaminated soils amended with inorganic (NPK and urea) and organic (cow dung and poultry litter) fertilizers and in some their combination. The incubation period ranged from 3-18 days. Bacterial population count and residual hydrocarbon were determined .Results showed that bacterial population count increased as the microbes utilized hydrocarbon for carbon and energy sources, the increase in population count and degradation of the hydrocarbons was stimulated by the fertilizer. It was also observed that as the population count increased due to hydrocarbon utilization for carbon and energy, residual hydrocarbon decreased and percentage degradation increased. Urea fertilizer was the best amendment for E.coli to degrade kerosene, NPK and cow dung differently aided the same E.coli in degrading engine oil. Pseudomonas and Proteus species degraded kerosene and fuel better in the presence of NPK fertilizer. Klebsiella specie degraded diesel and engine oil better when amended with poultry litter and cow dung respectively at least for the first 9 days. More than 90% of the hydrocarbons were degraded within each incubation period. The microbes began to die as from the 15 th day of incubation, this may be due to secretion of toxic secondary metabolites. Control experiments revealed that there was initial increase in population count of the microbes as they utilized the hydrocarbon for carbon and energy, but they began to die because of non-stimulation with fertilizer, therefore less than 50% of the hydrocarbons were degraded in all the control experiments. Maize seeds grew on the remediated soil within six (6) days of planting.
Wood is a natural renewable polymeric composite made up of cellulose, hemicelluloses, lignin and ... more Wood is a natural renewable polymeric composite made up of cellulose, hemicelluloses, lignin and extractives. Surface characterization of eight timbers collected from South Eastern Nigeria was performed using Fourier Transform Infrared spectroscopy (FTIR) and thermal degradation pattern was determined by Thermogravimetric analysis (TGA). The infrared bands of the selected wood species with their peak assignments and structural polymers show that the positions of most bands and their intensities in the fingerprint region are similar. Qualitatively, these timbers yielded thermogravimetric responses that are also similar. Results suggest that Erythrophleum suaveolens and Nauclea latifolia would be better lignocellulose substitute resins, as they present higher amounts of lignin and higher thermal decomposition temperature.
This work investigated and quantified the calorific values of the main branches and trunks of ele... more This work investigated and quantified the calorific values of the main branches and trunks of eleven (11) tropical trees in correlation with their chemical composition in order to assess their suitability for use as credible sources of wood fuel. The determination of the carbon, hydrogen, nitrogen, oxygen and sulphur (CHNOS) content of the samples was done using an organic elemental analyser, while an oxygen bomb calorimeter was used to experimentally determine their corresponding gross heat values. The experimental gross heat values for the branches examined ranged from 18,703.37 kJ/kg in Lophira lanceolata to 21,350.35 kJ/kg in Afzelia africana while that of the trunks ranged from 19,747.74 kJ/kg in Tectonia grandis to 22,408.68 kJ/kg in Prosopis africana. These values were within and about the expected ranges observed for tropical trees and may be considered adequate for wood fuel. The general trend in both branches and trunks was that the higher the carbon content, the higher the gross heat value of sample. The absence of sulphur in almost all the samples except, Prosopis africana, (0.055%) was indicative of the fact that the negative environmental impact with respect to harmful emissions of oxides of sulphur is practically non-existent with respect to these species. In the light of the aforementioned variables, the main branches of Afzelia africana (21,350.35 kJ/kg), Nauclea diderrichii (21,157.30 kJ/kg) and Tectonia grandis (20,257.13 kJ/kg) could be used as credible sources of firewood and charcoal production. With respect to the trunks, the timbers in order of preference would ideally be Prosopis africana (22,408.68 kJ/kg), Nauclea diderichii (21,436.42 kJ/kg) and Brachstigia eurychoma (20,924.7 kJ/kg).
Timber has always played an influencing role in the lives of humans. At high temperature and in t... more Timber has always played an influencing role in the lives of humans. At high temperature and in the presence of air, it burns or decomposes exothermically. The flame characteristics studied were the ignition time, flame duration, flame propagation rate and afterglow time. Wet and oven-dry densities, moisture content and porosity index of these timbers were also measured. The oven-dry density range was 0.256 0.008 g/cm 3 to 1.111 0.039 g/cm 3 in which most of the timbers were of medium density (0.400-0.750 g/cm 3). Most of the timbers can be described as being fire-tolerant since they have flame propagation rate values below 0.28cm/s. There was somewhat direct relationship between oven-dry density and ignition time, flame duration and afterglow time of these timbers, while an inverse trend exists with flame propagation rate. The use of alternative hardwoods with high density is recommended with its attendant flame characteristics.
GSC biological and pharmaceutical sciences, Oct 29, 2023
The present work highlights the use of Ipomoea involucrate B. flower extract as a complexometric ... more The present work highlights the use of Ipomoea involucrate B. flower extract as a complexometric indicator in complex formation between the EDTA and the following metal solutions (Cu 2 , + Ba 2 , + Hg 2+ , Fe 3+ , and Bi 3+). Ipomoea involucrate is a species of the Ipomoea genus, belonging to the family Convolvulaceae. This natural indicator was extracted in 2M HCl at 100 0 C for 30-40 minutes, cooled and the extract filtered and extracted with ethyl acetate and the pigment extracted with amyl alcohol which was separated and concentrated over a water bath. The flower extract was screened for its use as an metallochromic indicator at different pHs in metal solutions of Cu 2 , + Ba 2 , + Hg 2+ , Fe 3+ , and Bi 3+ .This natural indicator from the results obtained gave sharp intense color change at the equivalence point of complex formation between the metals and the EDTA at both acidic and alkaline pHs in the metal solution of Cu 2+ and Fe 3+ and that with different amount of EDTA used in the titration, which increased as the pH value increased, while the ipomoea indicator gave sharp intense color change at the equivalence point of complex formation between the metals and the EDTA at alkaline pHs in the metal solution of Ba 2+ , Hg 2+ and Bi 3+ at pH > 10. Natural flower indicators could take the place of the synthetic metallochromic indicators currently used in conventional laboratories because these flower extracts have excellent performance with sharp and intense color change in end points during the complexometric titrations and simple, costeffective and environmentally friendly extraction methods.
Wood is a heterogeneous, hygroscopic, cellular and anisotropic material of biological origin. The... more Wood is a heterogeneous, hygroscopic, cellular and anisotropic material of biological origin. The properties of wood that make it an ideal raw material for several purposes are mainly determined by the specific architecture of the cell walls. Moisture content, porosity and water imbitition capacity contribute to the quality of timber. The examination of the internal microscopic structure of the timber samples will be done by Scanning Electron Microscopy (SEM). Of the fifty-three timbers studied, thirty-two were of medium density (0.403 ± 0.020 to 0.715 ± 0.011 g/cm 3) , ten were of low density (0.256 ± 0.008 to 0.380 ± 0.012 g/cm 3) and eleven were quite dense (0.784 ± 0.020 to 1.111 ± 0.039 g/cm 3), with Ricinodendrom heudelotti having the least value and Irvinga smithii, the highest. Water imbibitions capacity after 24 hours was quite high for Ricinodendrom heudelotti and Ceiba pentandra while that for Irvinga smithii, Lophira lanceolate, Khaya senegalensis and Erythrophleum suaveolens were low. There was an inverse relationship between the maximum moisture content of these wood samples and their density. The scanning electron micrographs of selected timbers present ring-porous hardwoods as well as diffuse-poruos hardwoods.Fibrous nature of Entradrophragma utile and Hollarhena floribunda may account for their high moisture content (MC) values while the spherical granules in Tetrapluera tetraptera are suspected to be hydrophobic since the water imbibition capacity observed after 24h was lower than those of similar density.
Journal of Sustainable Bioenergy Systems, Dec 31, 2022
This work investigated and quantified the physicochemical, structural and morphological propertie... more This work investigated and quantified the physicochemical, structural and morphological properties of four (4) tropical timbers as precursor raw materials for possible utilization in the wood plastic industry. The physicochemical properties of the wood samples such as the bulk and tapped density, moisture content, water absorption capacity at 25˚C, volatile content, fixed carbon, ash content, alpha cellulose, hemicellulose, lignin, and extractives contents were determined using standard methods like the European Committee for Standardization and (CEN/TS) and the American Society for Testing Materials (ASTM) standards. The structural and morphological properties of the samples were examined with Fourier Infrared Transform (FTIR) spectroscopy and scanning electron microscope (SEM). Results indicated that the bulk density values of the timbers ranged from 0.34 g/cm 3 in Brachystegia eurycoma (W 3) to 0.47 g/cm 3 in Erythrophleum suaveolens (W 2), with the other timbers, Nuclea diderichii (W 1) and Prosopis africana (W 4) having the same bulk density of 0.40 g/cm 3. With respect to their moisture content, W 2 had the highest value (8.38%) while Nauclea diderrichii had the lowest value (6.52%). The water absorption capacities of the woods studied correlated with the cellulose composition of wood in the order of: W 3 > W 1 > W 4 > W 2. The FTIR results showed that W 2 and W 3 presented a slightly more prominent and broader band than the other woods at 1731 cm −1 , in agreement with the higher holocellulose content of these species, while W 2 and W 4 presented the most prominent peaks indicating higher lignin content than W 1 and W 3. The SEM micrographs of the wood flour samples investigated indicated that the surfaces of the woods were rough and heterogeneous with irregular crystal and
Organophosphorus esters fulfil many industrial, agricultural, and household roles. Nature has dep... more Organophosphorus esters fulfil many industrial, agricultural, and household roles. Nature has deployed phosphates and their related anhydrides as energy carriers and reservoirs, as constituents of genetic materials in the form of DNA and RNA, and as intermediates in key biochemical conversions. The transfer of the phosphoryl (PO3) group is thus a ubiquitous biological process that is involved in a variety of transformations at the cellular level such as bioenergy and signals transductions. Significant attention has been paid in the last seven decades to understanding the mechanisms of uncatalyzed (solution) chemistry of the phospho group transfer because of the notion that enzymes convert the dissociative transition state structures in the uncatalyzed reactions into associative ones in the biological processes. In this regard, it has also been proposed that the rate enhancements enacted by enzymes result from the desolvation of the ground state in the hydrophobic active site environ...
Recently, natural fibers have gained research attention in reinforcing polymers due to their avai... more Recently, natural fibers have gained research attention in reinforcing polymers due to their availability and unique properties in polymer applications. Preliminary studies indicate indiscriminate disposal of human hair (HH) and the burning of cow hair (CH) and sheep hair (SH) by abattoir operators in Nigeria; this has become a source of concern owing to the hazardous nature of these activities to human health and the environment. This study is, therefore, essential and seeks to utilize these waste materials in an environmentally sustainable way, as the hair fibers used in this work are renewable and will enhance the economy of any country if adequately utilized. The composites of Polypropylene (PP), human, sheep, and cow tail hair fibers were prepared at different weight percentage concentrations of 0, 2, 4, 6, and 8 w% using an injection molding machine. Untreated and treated PP composites were analyzed for average diameter, length, and density; the composites were also characterized for ultimate tensile strength, flexural strength, hardness, and impact strength. The average diameter assessment indicates viz: Cow tail hair > Human hair > Sheep hair. The sequence for hair fiber lengths shows that Sheep hair > Human hair > Cow hair, and the order for average density is Cow tail hair > Human hair > Sheep hair. The analysis of the mechanical properties of the reinforced and unreinforced PP composite showed that the Human hair/PP composite gave the best enhancement for ultimate tensile strength and modulus, flexural strength, and modulus at 8% fiber loading. Cow tail hair/PP composite yielded the best elongation at break at 2% fiber loading. Human hair/PP composite showed the best yield for impact strength at 4% fiber loading, while the Cow tail hair composite performed best for the hardness test at 2% fiber loading. The surface scanning electronic microscope (SEM) images showed no significant manufacturing defect on composites except for the air entrapment in the image of cow tail hair. The study also observed that there is no fiber breakage or void observed in the images. SEM images of the PP-composites interface at 8% maximum loading showed reasonably good fiber adhesion to the polymer matrix. This study is recommended for environmental sustainability and to improve material properties for various applications.
Polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are predominant pollutants linked ... more Polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are predominant pollutants linked with anthropogenic activities across a host of environmental mediums. The level of pollution, ecological and health risk were assessed in surface water from Ekulu in Enugu metropolis, Nigeria for 17 PAHs and selected HMs (As, Cd, Cr, Cu, Pb, Ni, Zn) components. PAHs and HMs were determined using a gas chromatography-flame ionization detector (GC-FID) and atomic adsorption spectrophotometer (AAS). The total PAHs in station A (3.17mg/l), B (1.51mg/l), and C (1.83mg/l) were due to high molecular weight (HMW) PAHs than low molecular weight (HMW) PAHs. HMs contents were within USEPA and WHO minimum contamination levels (MCL) except Cr and Pb. The molecular diagnostics of PAHs showed that incomplete combustion of carbonaceous compounds was dominant, while petrogenic was insignificant across all samples. The ecological indices of PAHs and HMs varied from medium to high pollution due to anthropo...
Current Research in Green and Sustainable Chemistry
There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement du... more There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement due to their toughness and light weight. In this research, low density polyethylene (LDPE) was reinforced using 0.25 M NaOH treated cow tail, human and sheep hair fibers at 2, 4, 6 and 8% concentration respectively prior to injection moulding. The average densities, diameters and lengths of hair fibres were assessed The results obtained from the analysis of reinforced LDPE composites indicated that cow tail hair gave the highest average density and diameter. Sheep hair had the highest length after grinding. The study also analyzed the ultimate tensile strength and modulus, flexural strength and modulus, elongation, impact and hardness test on the polymer and their composites as well as the morphology and statistical analysis of the composite. This study indicated that human hair LDPE composites achieved highest flexural strength, flexural modulus, ultimate tensile strength and tensile modulus at 8% fibre loading whereas elongation at break and hardness were at 4% fibre loading while impact strength was at 2%. The cow tail hair LDPE composite gave the best impact strength at 8% fibre loading and sheep hair at 6%. The SEM results showed no serious manufacturing defects on the composites. The analysis of variance indicated that only the means of the composites' flexural properties were statistically significant. This study shows that short animal hair fibres could be effectively used to reinforced LDPE, and therefore suggest an alternative waste management strategy of these natural fibres that are currently viewed as environmental nuisance in the study area.
Current Research in Green and Sustainable Chemistry, 2022
There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement du... more There is increased enthusiasm towards the use of natural hair fibers for plastic reinforcement due to their toughness and light weight. In this research, low density polyethylene (LDPE) was reinforced using 0.25 M NaOH treated cow tail, human and sheep hair fibers at 2, 4, 6 and 8% concentration respectively prior to injection moulding. The average densities, diameters and lengths of hair fibres were assessed The results obtained from the analysis of reinforced LDPE composites indicated that cow tail hair gave the highest average density and diameter. Sheep hair had the highest length after grinding. The study also analyzed the ultimate tensile strength and modulus, flexural strength and modulus, elongation, impact and hardness test on the polymer and their composites as well as the morphology and statistical analysis of the composite. This study indicated that human hair LDPE composites achieved highest flexural strength, flexural modulus, ultimate tensile strength and tensile modulus at 8% fibre loading whereas elongation at break and hardness were at 4% fibre loading while impact strength was at 2%. The cow tail hair LDPE composite gave the best impact strength at 8% fibre loading and sheep hair at 6%. The SEM results showed no serious manufacturing defects on the composites. The analysis of variance indicated that only the means of the composites' flexural properties were statistically significant. This study shows that short animal hair fibres could be effectively used to reinforced LDPE, and therefore suggest an alternative waste management strategy of these natural fibres that are currently viewed as environmental nuisance in the study area.
American Scientific Research Journal for Engineering, Technology, and Sciences, 2019
The purpose of this study is to reduce the flammability of Gmelina arborea using fire retardants.... more The purpose of this study is to reduce the flammability of Gmelina arborea using fire retardants. This becomes necessary because fire has caused a lot of devastating effect to mankind since its discovery. Gmelina arborea splints were immersed in different concentrations of antimony trichloride, ammonium sulphamate and mixture of the antimony trichloride and ammonium sulphamate to determine the ignition time (IT), flame propagation rate (FPR) and after-glow time (AGT). The results indicated reduction in flame propagation rate and after-glow time for the three flame retardants while ignition time was increased with increase in concentration for the retardants. It was also observed that the combined flame retardants gave the highest ignition time and least flame propagation rate and after-glow time among the three flame retardants used. These flame retardants can be used especially the mixture of antimony trichloride and ammonium sulphamate to hinder/slow the ignitability of Gmelina ar...
Journal of Petroleum Environmental Biotechnology, Feb 22, 2012
Different microbes (E.coli, Proteus, Klebsiella and Pseudomonas sp) were utilized in degradation ... more Different microbes (E.coli, Proteus, Klebsiella and Pseudomonas sp) were utilized in degradation of different hydrocarbon (Engine oil/diesel, kerosene and fuel) contaminated soils amended with inorganic (NPK and urea) and organic (cow dung and poultry litter) fertilizers and in some their combination. The incubation period ranged from 3-18 days. Bacterial population count and residual hydrocarbon were determined .Results showed that bacterial population count increased as the microbes utilized hydrocarbon for carbon and energy sources, the increase in population count and degradation of the hydrocarbons was stimulated by the fertilizer. It was also observed that as the population count increased due to hydrocarbon utilization for carbon and energy, residual hydrocarbon decreased and percentage degradation increased. Urea fertilizer was the best amendment for E.coli to degrade kerosene, NPK and cow dung differently aided the same E.coli in degrading engine oil. Pseudomonas and Proteus species degraded kerosene and fuel better in the presence of NPK fertilizer. Klebsiella specie degraded diesel and engine oil better when amended with poultry litter and cow dung respectively at least for the first 9 days. More than 90% of the hydrocarbons were degraded within each incubation period. The microbes began to die as from the 15 th day of incubation, this may be due to secretion of toxic secondary metabolites. Control experiments revealed that there was initial increase in population count of the microbes as they utilized the hydrocarbon for carbon and energy, but they began to die because of non-stimulation with fertilizer, therefore less than 50% of the hydrocarbons were degraded in all the control experiments. Maize seeds grew on the remediated soil within six (6) days of planting.
Wood is a natural renewable polymeric composite made up of cellulose, hemicelluloses, lignin and ... more Wood is a natural renewable polymeric composite made up of cellulose, hemicelluloses, lignin and extractives. Surface characterization of eight timbers collected from South Eastern Nigeria was performed using Fourier Transform Infrared spectroscopy (FTIR) and thermal degradation pattern was determined by Thermogravimetric analysis (TGA). The infrared bands of the selected wood species with their peak assignments and structural polymers show that the positions of most bands and their intensities in the fingerprint region are similar. Qualitatively, these timbers yielded thermogravimetric responses that are also similar. Results suggest that Erythrophleum suaveolens and Nauclea latifolia would be better lignocellulose substitute resins, as they present higher amounts of lignin and higher thermal decomposition temperature.
This work investigated and quantified the calorific values of the main branches and trunks of ele... more This work investigated and quantified the calorific values of the main branches and trunks of eleven (11) tropical trees in correlation with their chemical composition in order to assess their suitability for use as credible sources of wood fuel. The determination of the carbon, hydrogen, nitrogen, oxygen and sulphur (CHNOS) content of the samples was done using an organic elemental analyser, while an oxygen bomb calorimeter was used to experimentally determine their corresponding gross heat values. The experimental gross heat values for the branches examined ranged from 18,703.37 kJ/kg in Lophira lanceolata to 21,350.35 kJ/kg in Afzelia africana while that of the trunks ranged from 19,747.74 kJ/kg in Tectonia grandis to 22,408.68 kJ/kg in Prosopis africana. These values were within and about the expected ranges observed for tropical trees and may be considered adequate for wood fuel. The general trend in both branches and trunks was that the higher the carbon content, the higher the gross heat value of sample. The absence of sulphur in almost all the samples except, Prosopis africana, (0.055%) was indicative of the fact that the negative environmental impact with respect to harmful emissions of oxides of sulphur is practically non-existent with respect to these species. In the light of the aforementioned variables, the main branches of Afzelia africana (21,350.35 kJ/kg), Nauclea diderrichii (21,157.30 kJ/kg) and Tectonia grandis (20,257.13 kJ/kg) could be used as credible sources of firewood and charcoal production. With respect to the trunks, the timbers in order of preference would ideally be Prosopis africana (22,408.68 kJ/kg), Nauclea diderichii (21,436.42 kJ/kg) and Brachstigia eurychoma (20,924.7 kJ/kg).
Timber has always played an influencing role in the lives of humans. At high temperature and in t... more Timber has always played an influencing role in the lives of humans. At high temperature and in the presence of air, it burns or decomposes exothermically. The flame characteristics studied were the ignition time, flame duration, flame propagation rate and afterglow time. Wet and oven-dry densities, moisture content and porosity index of these timbers were also measured. The oven-dry density range was 0.256 0.008 g/cm 3 to 1.111 0.039 g/cm 3 in which most of the timbers were of medium density (0.400-0.750 g/cm 3). Most of the timbers can be described as being fire-tolerant since they have flame propagation rate values below 0.28cm/s. There was somewhat direct relationship between oven-dry density and ignition time, flame duration and afterglow time of these timbers, while an inverse trend exists with flame propagation rate. The use of alternative hardwoods with high density is recommended with its attendant flame characteristics.
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