This paperpresents thereport of an investigationon the effect of differentmicrostructures ofNST-6... more This paperpresents thereport of an investigationon the effect of differentmicrostructures ofNST-60 Mn steel on its corrosion wear resistance in cocoa mucilage The corrosion wear resistance was investigated under an instrumented pin-on-disc wear test rig. The microstructure of the steel was varied by heat treatment procedures such as water-quenching, austempering, martempering and water-quenching plus tempering at 250 o C. A variation of the pH, time of exposure and applied load on the corrosion wear resistance of the heat treated sampleswere evaluated. The results obtained showed that hardness is inversely proportional to the rate of wear of the NST-60 Mn steel. Also, the microstructure of the water-quenched sample exhibited the greatest wear resistance in air, cocoa mucilage of pH3.9 and pH4.2 while the as-received NST 60 Mn steel showed the poorest corrosion wear resistance in the same media.
This paper has evaluated the co-inhibitive characteristics of sodium tungstate with sodium nitrat... more This paper has evaluated the co-inhibitive characteristics of sodium tungstate with sodium nitrate in 0.085 M hydrochloric acid. The inhibition study was carried out using the gravimetric technique. The uninhibited solution of 0.085 M hydrochloric acid served as the control. The effect of addition of single inhibitor and co-inhibitors at 50 (parts per million) ppm, 100 ppm, and 150 ppm on corrosion rates (CR) (mpy) and inhibition efficiencies (IE) was investigated. The results showed that sodium tungstate alone gave 47% IE and sodium nitrate produced 57% IE when used alone after 336 hours of exposure. The inhibitive efficiency of 54% was obtained at 150 ppm of sodium nitrate and 50 ppm of sodium tungstate after 336 hours of exposure. Based on the result obtained sodium tungstate must be in lower concentration than sodium nitrate for effective inhibitive efficiency.
The inhibitive effect of cocoa (Theobroma Cacao) and kolanut (Cola Acuminata) extracts on the cor... more The inhibitive effect of cocoa (Theobroma Cacao) and kolanut (Cola Acuminata) extracts on the corrosion of mild steel in seawater at room temperature has been investigated. The study was carried out using the gravimetric technique. The results showed kola and cocoa leaves extracts as potential inhibitors of mild steel corrosion in seawater and marine environment. The highest inhibition efficiency was obtained when the concentration of the inhibitors was increased up to optimum. There was a sign of synergism when 4% of each of the extracts were used to inhibit corrosion in the seawater.
International Journal of Materials Forming and Machining Processes, 2017
The study determined the effect of cutting parameters on the surface residual stress of face-mill... more The study determined the effect of cutting parameters on the surface residual stress of face-milled pearlitic ductile iron with a view to enhancing surface integrity of machined parts in the manufacturing industries. The pearlitic ductile iron used for this study was prepared and four cutting parameters were considered. The results obtained showed that the average surface residual stress of the machined surfaces was tensile and increased significantly with increase in depth of cut. Feed rate and cutting speed exhibited some effect, though not statistically significant, on average surface residual stress. The average residual stress was found to decrease significantly and drastically from 605.39 MPa to 101.72 MPa as cutting fluid flow rate increased from 0 ?/min to 4 ?/min. The study concluded that out of all four cutting parameters investigated, the cutting fluid flow rate has most considerable influence on the surface residual stress of the machined pearlitic ductile iron.
The development of natural biomaterials is not regarded as a new area of science, but has existed... more The development of natural biomaterials is not regarded as a new area of science, but has existed for centuries. The use of natural products as a biomaterial is currently undergoing a renaissance in the biomedical field. The major limitations of natural biomaterials are due to the immunogenic response that can occur following implantation and the lot-to-lot variability in molecular structure associated with animal sourcing. The chemical stability and biocompatibility of natural products in the body greatly accounts for their utilization in recent times. The paper succinctly defines biomaterials in terms of natural products and also that natural products as materials in biomedical fields are considerably versatile and promising. The various types of natural products and forms of biomaterials are highlighted. Three main areas of applications of natural products as materials in medicine are described, namely, wound management products, drug delivery systems, and tissue engineering. Thi...
Cassava has been found to contain cyanogenic glucoside, which is hydrolyzed to cyanide as a waste... more Cassava has been found to contain cyanogenic glucoside, which is hydrolyzed to cyanide as a waste product during cassava processing. This cyanide content is found to vary in the various parts of the cassava plant. Powdered cassava leaf has been utilized to pack cyanide mild ...
This article reports a detailed analysis of a failure observed in a petroleum trunkline in the Ni... more This article reports a detailed analysis of a failure observed in a petroleum trunkline in the Niger Delta region of southwestern Nigeria. The study was carried out using various techniques including metallurgical, chemical, and x-ray analysis. Leakage was observed along a petroleum trunkline route, and excavation of the trunkline revealed that the trunkline had actually fractured along the 6 o’clock
This paperpresents thereport of an investigationon the effect of differentmicrostructures ofNST-6... more This paperpresents thereport of an investigationon the effect of differentmicrostructures ofNST-60 Mn steel on its corrosion wear resistance in cocoa mucilage The corrosion wear resistance was investigated under an instrumented pin-on-disc wear test rig. The microstructure of the steel was varied by heat treatment procedures such as water-quenching, austempering, martempering and water-quenching plus tempering at 250 o C. A variation of the pH, time of exposure and applied load on the corrosion wear resistance of the heat treated sampleswere evaluated. The results obtained showed that hardness is inversely proportional to the rate of wear of the NST-60 Mn steel. Also, the microstructure of the water-quenched sample exhibited the greatest wear resistance in air, cocoa mucilage of pH3.9 and pH4.2 while the as-received NST 60 Mn steel showed the poorest corrosion wear resistance in the same media.
This paper has evaluated the co-inhibitive characteristics of sodium tungstate with sodium nitrat... more This paper has evaluated the co-inhibitive characteristics of sodium tungstate with sodium nitrate in 0.085 M hydrochloric acid. The inhibition study was carried out using the gravimetric technique. The uninhibited solution of 0.085 M hydrochloric acid served as the control. The effect of addition of single inhibitor and co-inhibitors at 50 (parts per million) ppm, 100 ppm, and 150 ppm on corrosion rates (CR) (mpy) and inhibition efficiencies (IE) was investigated. The results showed that sodium tungstate alone gave 47% IE and sodium nitrate produced 57% IE when used alone after 336 hours of exposure. The inhibitive efficiency of 54% was obtained at 150 ppm of sodium nitrate and 50 ppm of sodium tungstate after 336 hours of exposure. Based on the result obtained sodium tungstate must be in lower concentration than sodium nitrate for effective inhibitive efficiency.
The inhibitive effect of cocoa (Theobroma Cacao) and kolanut (Cola Acuminata) extracts on the cor... more The inhibitive effect of cocoa (Theobroma Cacao) and kolanut (Cola Acuminata) extracts on the corrosion of mild steel in seawater at room temperature has been investigated. The study was carried out using the gravimetric technique. The results showed kola and cocoa leaves extracts as potential inhibitors of mild steel corrosion in seawater and marine environment. The highest inhibition efficiency was obtained when the concentration of the inhibitors was increased up to optimum. There was a sign of synergism when 4% of each of the extracts were used to inhibit corrosion in the seawater.
International Journal of Materials Forming and Machining Processes, 2017
The study determined the effect of cutting parameters on the surface residual stress of face-mill... more The study determined the effect of cutting parameters on the surface residual stress of face-milled pearlitic ductile iron with a view to enhancing surface integrity of machined parts in the manufacturing industries. The pearlitic ductile iron used for this study was prepared and four cutting parameters were considered. The results obtained showed that the average surface residual stress of the machined surfaces was tensile and increased significantly with increase in depth of cut. Feed rate and cutting speed exhibited some effect, though not statistically significant, on average surface residual stress. The average residual stress was found to decrease significantly and drastically from 605.39 MPa to 101.72 MPa as cutting fluid flow rate increased from 0 ?/min to 4 ?/min. The study concluded that out of all four cutting parameters investigated, the cutting fluid flow rate has most considerable influence on the surface residual stress of the machined pearlitic ductile iron.
The development of natural biomaterials is not regarded as a new area of science, but has existed... more The development of natural biomaterials is not regarded as a new area of science, but has existed for centuries. The use of natural products as a biomaterial is currently undergoing a renaissance in the biomedical field. The major limitations of natural biomaterials are due to the immunogenic response that can occur following implantation and the lot-to-lot variability in molecular structure associated with animal sourcing. The chemical stability and biocompatibility of natural products in the body greatly accounts for their utilization in recent times. The paper succinctly defines biomaterials in terms of natural products and also that natural products as materials in biomedical fields are considerably versatile and promising. The various types of natural products and forms of biomaterials are highlighted. Three main areas of applications of natural products as materials in medicine are described, namely, wound management products, drug delivery systems, and tissue engineering. Thi...
Cassava has been found to contain cyanogenic glucoside, which is hydrolyzed to cyanide as a waste... more Cassava has been found to contain cyanogenic glucoside, which is hydrolyzed to cyanide as a waste product during cassava processing. This cyanide content is found to vary in the various parts of the cassava plant. Powdered cassava leaf has been utilized to pack cyanide mild ...
This article reports a detailed analysis of a failure observed in a petroleum trunkline in the Ni... more This article reports a detailed analysis of a failure observed in a petroleum trunkline in the Niger Delta region of southwestern Nigeria. The study was carried out using various techniques including metallurgical, chemical, and x-ray analysis. Leakage was observed along a petroleum trunkline route, and excavation of the trunkline revealed that the trunkline had actually fractured along the 6 o’clock
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Papers by Engr. L. E. Umoru