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The lack of chemical plants for the manufacture of simple chemicals such as NaOH, KOH and KCOin most part of 2 3 sub-Saharan African countries leads to high cost of importing these chemicals which make them less readily available for many industrial purposes. An investigation was carried out using waste plantain peels to produce potassium carbonate for industrial purposes such as paper making, glass making, soap making etc. The elemental composition analysis result of ashed plantain peel shows K(42.16%), Al(1.773%), P (0.758%), Ca (0.162%) and some other Trace elements (52.817%). The thermal decomposition of the product was investigated using Thermo gravimetric Analysis (TGA) which indicates the stability and decomposition status of produced. The purity morphology of the synthesized product shows major peaks attributed to potassium carbonate which assign JCPDS file number {98-1435} and minor silica {14-1303}. Finally, FTIR analysis was carried out which shows the band ranges of compounds present in the produced silica which includes: OH (2500- 3500Cm), K - O (624 Cm ), Si-O -1-1 (427 Cm). The application of the synthesized product was recommended as a potential candidate in soap making -1 industries.

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The present study examines the physicochemical parameters and heavy metal contents of soil from Okpella Mining Area in Edo State. Top soil samples and control samples from about 200m from the mining area were analyzed for their heavy metals content using Atomic Absorption Spectrometer (AAS) techniques. The pH, electrical conductivity and organic matter were determined using standard procedures. The soil pH ranged from 6.8 to 7.9 which show slightly acidic to alkaline conditions. The concentrations of the metals in mg/kg were as follows: Cu (23.03 to 170.83), Pb (3.50 to 10.59), Cd (0.70 to 1.93), Cr (0.75 to 8.74), Ni (5.0 to 34.52), Zn (3.29 to 25.46), Mn (3.49 to 22.50), Fe (22.03 to105.67), Co (9.99 to 64.43) and As (0.35 to 1.20). Inter elemental correlation showed that most of the metals investigated were of common origin. The mean concentrations of the metals were in the general order: Cu>Fe> Co> Ni> Zn>Mn>Pb>Cr>Cd>As. The concentrations of the metals at mining area were generally higher than control. With the exception of Cd, the concentration of other metals analyzed were within safe limit based on WHO standard. Results from pollution index assessment also show that Cd has higher degree of contamination. There is therefore need to monitor agricultural activities going on in this area so as to guard the safety of man and organisms in the area

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The Selective Laser Melting (SLM) is one of the Additive Manufacturing (AM) processes and it is more favoured over Selective Laser Sintering (SLS) because it can consolidate metal powders to a near full density (with relative density of more than 99%) and it can achieve a surface roughness of less than 20µm. However, the SLM process involves the use of high density energy laser to operate, by melting and re-solidification at very fast rates, which makes it very prone to defects and failures, like cracking, balling, delamination. Residual stresses are also caused by the high thermal gradient between the melt pool and the powder solid. A three-dimensional Finite Element Model (FEM) of selective laser melting was developed by using ANSYS software (workbench module 16.2) to predict the unsteady temperature evolution and distribution between the melt pool and the powder solid. The model incorporated a coupled thermal and mechanical simulation with convection. Temperature dependent material properties were also incorporated into the model. The moving heat source was described as a Gaussian distribution. It was observed that the heat accumulated during the previous scan tracks affected the next scan track and that the heat distribution to the surrounding powder bed was due to the fact that the heated-up material has greater conductivity than the untreated powder in front of the laser. This insight may be useful in the production of as fabricated parts by the SLM process.

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The Nigerian Steel (NST) 37-2 has vast applications as a substitute for foreign steels in Nigeria, but, its reliability, the effects of induced residual stress in the material, optimum cutting parameters, efficient process planning, chip formation process and surface roughness of the machined products are some of the challenges faced in the industry. In this study, the finite element modelling and simulation of orthogonal cutting of NST 37-2 steel was carried out, and the effect of cutting speed was investigated to address informed predictability on the material. The finite element simulations were conducted by using the ABAQUS software. The Johnson-Cook plastic and damage models were employed together with arbitrary Lagrangian-Eulerian (ALE) formulations. The results showed mainly continuous chip formation for all simulations. It was observed that the cutting and the thrust forces decreased with increase in cutting speed. Also, the temperature of the shear zone region increased with increase in cutting speed

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Rapid Prototyping, which can also be referred to as Solid Freeform Fabrication, Additive Manufacturing, Layered Manufacturing, or 3D Printing is a process of making a three-dimensional solid object of virtually any shape from a digital computer model. This paper reviews the advances in this printing technology with a view to popularizing its use for STEM and non-technical education among other uses. Illustrations were done using models of Mathematical objects including Hypercube and Icosidodecahedron; Engineering Objects including Automatic Transmission Gearing System, Brake Caliper and Suspension Bridge. Some of the other objects shown to have been 3D printed include: Building, Drone, Human Skull, Humanoid Robot, Human Teeth and Archeological Objects. The paper aims to enthuse and attract a large number of academics to embrace this technology that is already redefining a wide variety of systems and processes and also encourage materials scientists and engineers to expand the frontiers on range of feedstock materials that can be explored and used for 3D printing