Non edible oil sources have the potential to lower the cost of biodiesel. However, they usually contain significant high amounts of free fatty acids (FFA) that make them inadequate for direct base catalyzed transesterification reaction (where the FFA content should be lower than 3%). The present work reviews chemical re-esterification as a possible method for the pre-treatment of high FFA feedstock for biodiesel production. The effects of temperature, amount of glycerol, type and amount of catalyst have been discussed. Chemical re-esterification lowers FFA to acceptable levels for transesterification at the same time utilizing the glycerol by product from the same process. Further researches have been proposed as a way forward to improve the process kinetics and optimization so as to make it more economical.

A novel low temperature glycerolysis process for lowering free fatty acid (FFA) in crude jatropha oil for alkali catalyzed transesterification has been developed. The response surface methodology (RSM) based on central composite design was used to model and optimize the glycerolysis efficiency under three reaction variables namely; reaction time, temperature and glycerol to oil mass ratio. The optimum conditions for highest glycerolysis efficiency of 98.67% were found to be temperature of 65˚C, reaction time of 73 minutes and 2.24 g/g glycerol to oil mass ratio. These conditions lower the high free fatty acid of crude jatropha oil from 4.54% to 0.0654% which is below 3% recommended for alkali catalyzed transesterification. The pre-treated crude jatropha oil was then transesterified by using homogeneous base transesterification resulting to a conversion of 97.87%. The fuel properties of jatropha biodiesel obtained were found to be comparable to those of ASTM D6751 and EN 14214 standards. The process can also utilize the crude glycerol from the transesterification reaction, hence lowering the cost of biodiesel. The glycerolysis is easier implemented than acid esterification thereby avoiding the need for neutralization and alcohol removal step.

This study was conducted to investigate the application of extrusion cooking in the production of snacks containing soybean (SB) and Moringa oleifera (MO) leaves as inexpensive sources of micronutrients. The specific objectives were to examine effects of barrel temperature, residence time and moisture content of feed on selected physical properties of extruded snacks (extrudates), namely water absorption index (WAI), water solubility index (WSI) and expansion ratio (ER). The extrudates were obtained by blending different levels of input ingredients of maize flour (MF) (55 to 80%), full fat soybean flour (FFSF) (10 to 30%), and Moringa oleifera leaf powder (MOLP) (5 to 15%). Extrusion process variables in a twin-screw extruder were at three levels for temperature (100, 130 and 160°C), feed moisture content (15, 22.5 and 30%), and residence time (60, 75 and 90 s). The performed study revealed that the level of incorporation of both FFSF and MOLP, and feed moisture content have significant effects on the expansion ratio, water solubility index and water absorption index of the extrudates. It was concluded that the role of processing conditions and blending levels have a significant contribution to the quality characteristics of the soy-moringa expanded snacks.

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This study aimed at examining the influence of transformational and transactional leadership on organisational performance by using Ruaha Catholic University of Tanzania as a case study. Quantitative data was collected from 130 employees of the university by using a standard questionnaire. Data analysis was done by using descriptive and inferential statistics, specifically linear regression. Descriptive results were presented using frequencies, means and standard deviations while results from inferential statistics were presented in the form of correlations and regressions.  Transformational and transactional leadership were found to have mean values that are above average score and the difference between the two leadership styles were not significantly big. However, the findings show that leaders practised more of transactional leadership than transformational leadership since transactional leadership had higher mean score value. Moreover, the study found that both transformational and transactional leadership have significant positive linear relationships with organisational performance. The findings give an implication that both transformational and transactional leadership can be used concurrently to bring about positive results in an organisation.