Analysis of thermal-hydraulic transients for the Miniature Neutron Source Reactor (MNSR) in Ghana

Abstract: A mathematical model is presented that permits to simulate the effect of the cooling coils of the pool upper section on the reactor thermal-hydraulic behaviour of Ghana research reactor-1. The model is based on a lumped parameter description solved numerically using Matlab/Simulink tool which is a commercial software package with the capability of modelling dynamical and control systems. The model incorporates fuel grids and cooling coil models as well as radiating energy from the clad. In this model, the reactor tank and the pool is divided into three sections. The model predictions are qualified by comparing the results with experimental data. The effect of cooling the upper section of the pool on reactor thermal-hydraulic parameters using the cooling coil is presented and discussed. It was observed that all maximum values of the reactor thermalhydraulic parameters decrease when the cooling coil power is increased. Good agreement is found between the model predictions and the experimental results

Evaluation of maize (Zea mays L.) genotypes as a component of integrated stem borer (Chilo partellus Swinhoe) management in coastal region of Kenya

Open Access JournalA study was conducted at six sites of Kenya Coastal region to evaluate candidate maize genotypes for inclusion in stem borer IPM package for the area. Stem borer infestation/damage during the trial period were rather low but nonetheless, significant differences were observed between the insecticide (Carbofuran) and/orBacillus thuriengiensis (Bt) treated plots and the control. Yield loss due perhaps to levels of tolerance of the genotypes varied from 7 to 23%. Generally, varietal crosses were higher yielding than the open pollinated populations with grain yield itself being primarily influenced by number of ears harvested per plot. Therefore, tendency towards prolificacy also determined the choice of ICZ5, IC92M2 and IC92M5 as possible candidates