Effect of using vegetable oils as quenching media for pure commercial aluminium

This paper presents the effects of rate of heat extraction by groundnut, melon, palm kernel, shea butter and palm oils on the mechanical properties of various samples of pure commercial aluminium heat treated at 200°C, 250°C, 300°C and 350°C. Muffle furnace equipped with digital thermometer and thermocouple was used for the heat treatment. Tensile strength and hardness tests were carried out using Instron Universal Tester and Vickers hardness methods, respectively. Results obtained from the experiment were presented graphically. The results showed that palm kernel oil cools faster at 200°C and 250°C, while palm oil and shea butter oil quench faster at 300°C and 350°C, respectively. Palm kernel oil offers the highest elongation at 200°C, while at 350°C shea butter oil gave the best result. The best among the bio-quenching oils in providing good ductility is shea butter oil at 200°C, while at 300°C and 350°C groundnut oil give the best result. Highest hardness values were obtained from samples quenched in melon oil between 200°C-300°C. However, these values decreased with increased heating temperature probably due to density and viscosity variation with temperature rise. Similar observations were made on most of other samples quenched in other bio-quenching oils used in this experiment. This study shows that these locally available vegetable oils have promising potentials to serve as a possible replacement for non-biodegradable mineral oils in many applications

Ground Beetle Range Extensions: Six New Ohio Records (Coleoptera: Carabidae)

We newly report six ground beetles from Ohio, comprising Badister parviceps, Stenolophus dissimilis, Harpalus somnulentus, Pentagonica fiavipes, Agonum albicrus, and Lebia collaris