Browsing by Author "Kirabira, J.B"

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    The Concrete Reinforcing Value of Recycled Steel Bars in Uganda
    (IOSR Journal of Engineering, 2013) Senfuka, C.; Kirabira, J.B; Byauhanga, J.K.
    The energy absorbing capacity of the reinforcement bars in concrete only occurs after the yield point. If the yield point of steel is too high, stresses in the concrete reach failure level before the yield point of the steel, allowing the formation of large shear and bond stresses at time of yield and ultimate brittle collapse. High yield is equally associated with reduced yield platform and energy absorption. Steel reinforcement bars in Uganda, mainly cold twisted, are often of high yield even though they amply meet the standard ductility requirements. This has largely been attributed to their recycled origin. This research investigates the relationship between the elevated yield values and the residual element content which in turn is a direct result of steel recycling.
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    Phase Diagram Modelling of a Multicomponent Aqueous Solution of Katwe Salt Lake, Uganda
    (International Conference on Environmental Science and Technology, 2019) Lwanyaga, J.D.; Kasedde, H.; Kirabira, J.B;
    A methodology is developed to compute the phase diagram of a hexary system and to determine the mineral precipitation sequence upon removal of water. The methodology is applied to construct the phase diagram and precipitation sequence of the system ( in water. The thermodynamic model chosen is the Extended UNIQUAC. A 3D grid is constructed in order to solve this model in MATLAB. On the basis of this grid, a 3D phase diagram is calculated and a Jänecke projection is obtained. The precipitation sequence due to evaporation is calculated thus obtaining the coordinates of the solution along this path as well as the order of precipitation. The numerical model is also able to calculate all these steps for temperatures 0-110°C. In addition, the number of ions and the composition of the system can be varied in order to model other elective systems. The obtained results are well suited to be used for the design of sustainable salt extraction processes for both Sea and Lake brines.