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Item MAIZE STORAGE IN TERMITE MOUND CLAY, CONCRETE, AND STEEL SILOS IN THE HUMID TROPICS: COMPARISON AND EFFECT ON BACTERIAL AND FUNGAL COUNTS(2015) Omobowale M.O.Considering the inadequacy of grain storage structures in Nigeria, which has been partly attributed to high cost and unavailability of construction materials, this study investigated the suitability of using readily available termite mound clay (TMC) for grain silo construction in comparison to conventional reinforced conczu (RC) and galvanized steel (GS) silos for maize storage in the humid tropics. The extent to which temperature and relative humidity affected the quality of stored grain during 8-month unaerated storage, covering both dry and rainy seasons, was evaluated using bacterial and fungal counts as performance parameters. The initial bacterial count of3500 colony forming units (CFU) per gram (CFU g-1) increased to 120000, 11000, and 8800 CFU g-1 for TMC, RC, and GS silos, respectively. There was no fungal activity at the beginning of storage, but fungal activity increased to 1500, 5500, and 350 CFU g-1 in TMC, RC, and GS silos, respectively. Fungal activity was noticed in the TMC silo in the fourth month of storage, which coincided with the start of the rainy season. Fungal counts exceeded the acceptable threshold of 1000 CFU g-1 in the TMC and RC silos. Relative humidity was of greater significance than temperature in affecting all. maize quality parameters considered. TMC was found suitable for constructing silos for short-term grain storage under unaerated conditions. Modification of the current TMC silo design to address permeability issues is expected to improve its performance for longer-term maize storage.Item Comparative Analysis Of Tomato Plant (Lycopersiconesculentum) And Stubborn Grass (Eleusineindica)In The Phyto-Remediation Of Soils Polluted With Heavy Metals(Department of Agricultural and Environmental Engineering, University of Ibadan, Nigeria, 2015) Omobowale M.O.Item Performance evaluation of termite-mound clay, concrete and steel silos for the storage of maize grains in the humid tropics(Department of Agricultural and Environmental Engineering, University of Ibadan, Oyo State, Nigeria, 2016) Omobowale M.O.Item An Investigation into the Thermal Properties of Termite Mound Clay Applicable to Grain Silo Construction(Department of Agricultural and Environmental Engineering, University of Ibadan, Oyo State, Nigeria, 2015) Omobowale M.O.Provision of suitable grain silos in humid tropical climates has generated research interests on the possibility of using local materials for construction. Termite mound clay (TMC), a material available in abundance was investigated as a potential construction material. A major factor determining the suitability of construction materials for grain silos is its thermal properties. Therefore, thermal conductivity, specific heat capacity, thermal diffusivity and thermal mass of TMC were determined and compared with those of concrete and stainless steel which are commonly used for silo construction. TMC was collected, crushed and sieved using a 500pm sieve to remove coarse particles and foreign materials. The TMC powder obtained was mixed with water using volumetric ratio of 1:5 (i.e. water to clay) after which the thoroughly mixed clay was carefully fed into the mould and left to air-dry for 5 days. The samples were dried in the oven at 105oC for about 48 hours to remove all the moisture. Results revealed that thermal conductivity ranged from 0.17 to 0.24 W/(mK) with an average value of 0.21 compared to concrete and steel which range between 0.8 - 1.28 and 16.3 - 16.7 W/(mK) respectively. Specific heat capacity had an average value of 2576.94 J/(kgK) compared with concrete and steel which had values of 960 and 490 J/(kgK) respectively. Thermal diffusivity had a mean value of 1.47*10-8 m2/s in comparison to concrete and steel whose calculated values were 6.63 ><10-7 and 4.18 ><10-6 kJ/(m3 K) respectively while thermal mass had a mean value of 4723.5 kJ/(m3 K) compared to 2112.0 and 3831.8 kJ/(m3K) for concrete and steel respectively. It was concluded that TMC offers a thermally suitable alternative to these two for grain silo construction in the humid tropics.Item Problems facing Local Manufacturers in the Nigerian Agro-Allied Machine Fabrication Industry(Department of Agricultural and Environmental Engineering, Faculty of Technology, University of Ibadan, Nigeria., 2010) Omobowale M.O.This study investigates the challenges and opportunities of the local industries involved in the fabrication of agrorelated machinery in Nigeria. With the aid of personal interviews, on-spot assessment/visual inspection, a number of problems confronting these local industries were recorded. These include erratic power supply, cost of raw materials, level of automation, noise pollution, occupational hazards, instability in government policies, marketability and a general bias for machines fabricated locally. The government is currently making efforts at reviving the economy, yet the priorities set in addressing the problems of the local economy may not be aligned with the actual priority problems that local companies face in their daily business. The paper makes suggestions on how th e government could better address the primary concerns of the industry in areas like power supply, raw material pro - essing and sensitization of the Nigeria populac, towards appreciating and procuring locally made machines.Item Problems facing Local Manufacturers in the Nigerian Agro-Allied Machine Fabrication Industry(Department of Agricultural and Environmental Engineering, Faculty of Technology, University of Ibadan, Nigeria., 2010) Omobowale M.O.This study investigates the challenges and opportunities of the local industries involved in the fabrication of agrorelated machinery in Nigeria. With the aid of personal interviews, on-spot assessment/visual inspection, a number of problems confronting these local industries were recorded. These include erratic power supply, cost of raw materials, level of automation, noise pollution, occupational hazards, instability in government policies, marketability and a general bias for machines fabricated locally. The government is currently making efforts at reviving the economy, yet the priorities set in addressing the problems of the local economy may not be aligned with the actual priority problems that local companies face in their daily business. The paper makes suggestions on how th e government could better address the primary concerns of the industry in areas like power supply, raw material pro - essing and sensitization of the Nigeria populac, towards appreciating and procuring locally made machines.Item Trends in fiber characteristics of Nigerian grown bamboo and its effect on its impact and tensile strengths(Department of Agricultural and Environmental Engineering, University of Ibadan, Nigeria, 2008) Omobowale M.O.Variations in impact bending and tensile strengths of Bambusa vulgaris (Schrad) with increasing culm height were studied considering its fiber characteristics at the nodes and internodes along the length of the culm. At the nodes, statistical analysis revealed a weak but direct correlation between fiber length and tensile strength while fiber diameter had a strong but inverse relationship with it. Impact bending showed a direct but weak relationship with fiber length while it had an inverse and weak correlation with fiber diameter. For the internodes, a st-'^gn inverse relationship was established between fiber length and tensile strength while fiber diameter showed a direct but weak relationship. Impact bending and fiber length had a strong but inverse correlation while fiber length and impact bending revealed a direct and significant correlation.Item Effect of Fill Volume on Microclimate and Microbial Activity in Non-ventilated Clay Silos Storing Maize in the Humid Tropics(Department of Agricultural and Environmental Engineering, Faculty of Technology, University of Ibadan, 2019) Omobowale M.O.Silos have a fixed volume at the time of construction; harvests however vary from season to season. Complaints about severe postharvest losses in grains in the humid tropics of southern Nigeria necessitated a study into the effect of fill volume on quality of stored maize. Three clay silos labelled S1 to S3 of the same dimension and capacity (3.5 metric tonnes) were used. The silo walls were painted externally with gloss paint to reduce water absorption and filled with shelled maize. The first silo (S1) was filled with 3 tonnes, the second silo (S2) with 2 tonnes and the third (S3) filled with a tonne of maize for 6 months. Data was collected on microclimatic conditions within the silo and grain quality with increasing time of storage. Temperature, relative humidity (RH) and equilibrium moisture content (EMC) were recorded three times daily for each silo, focusing on the air between the grains and the headspace above the grains. Temperature fluctuations within S1 were smaller as indicated by the statistical range of 2 oC compared to S2 and S3 at 7 and 8 oC respectively. S3 showed high values of RH toward the end of storage, ranging between 65% to 80% at the top level and 76% at the bottom. EMC at the airspace above the grains in S1 increased from 12.0% at the beginning of storage in the dry season to 15.6% at the end of storage in the rainy season compared with S2 and S3 which increased from 12.0 to 17% and 12.0 to 17.2% respectively. Grains were found to be more prone to deterioration with decreasing level of fill because and increase in microbial activity was observed with a decreasing level of fill. Recommendations were made to farmers and grain aggregators on proper actions to take during grain storage given the peculiarities of the humid tropics.Item Effect of Fill Volume on Microclimate and Microbial Activity in Non-ventilated Clay Silos Storing Maize in the Humid Tropics(Department of Agricultural and Environmental Engineering, Faculty of Technology, University of Ibadan, 2019) Omobowale M.O.Silos have a fixed volume at the time of construction; harvests however vary from season to season. Complaints about severe postharvest losses in grains in the humid tropics of southern Nigeria necessitated a study into the effect of fill volume on quality of stored maize. Three clay silos labelled S1 to S3 of the same dimension and capacity (3.5 metric tonnes) were used. The silo walls were painted externally with gloss paint to reduce water absorption and filled with shelled maize. The first silo (S1) was filled with 3 tonnes, the second silo (S2) with 2 tonnes and the third (S3) filled with a tonne of maize for 6 months. Data was collected on microclimatic conditions within the silo and grain quality with increasing time of storage. Temperature, relative humidity (RH) and equilibrium moisture content (EMC) were recorded three times daily for each silo, focusing on the air between the grains and the headspace above the grains. Temperature fluctuations within S1 were smaller as indicated by the statistical range of 2 oC compared to S2 and S3 at 7 and 8 oC respectively. S3 showed high values of RH toward the end of storage, ranging between 65% to 80% at the top level and 76% at the bottom. EMC at the airspace above the grains in S1 increased from 12.0% at the beginning of storage in the dry season to 15.6% at the end of storage in the rainy season compared with S2 and S3 which increased from 12.0 to 17% and 12.0 to 17.2% respectively. Grains were found to be more prone to deterioration with decreasing level of fill because and increase in microbial activity was observed with a decreasing level of fill. Recommendations were made to farmers and grain aggregators on proper actions to take during grain storage given the peculiarities of the humid tropics.Item COMPARATIVE ANALYSIS OF PARTIAL EXTERNAL SHADING ON THE PERFORMANCE OF GREENHOUSE GROWN CUCUMBER {CUCUMIS SATIVUS) AND OKRA {ABELMOSCHUS ESCULENTUS)(Department of Agricultural and Environmental Engineering, University of Ibadan, Nigeria, 2019) Omobowale M.O.Greenhouse cultivation is highly influenced by the microclimate, which affects plant growth and development. Shading is an option for ensuring a relatively cool environment within tropical greenhouses which tends to heat up due to intense solar radiations. This study was aimed at comparing the microclimate between a partially shaded greenhouse and an unshaded one with respect to its effect on the crops. Cucumber (Cucumis sativus) and okra (Abelmoschus esculentus) were grown in two greenhouses during the dry season of early 2018. One greenhouse was shaded with white coloured high-density polythelene film at the roof level while the other greenhouse was left unshaded. Both greenhouses were naturally ventilated. Results showed that shading had a positive effect on the okra growth compared to the okra parameters observed in the unshaded greenhouse as there was significant difference in the leaf length, leaf breadth, stem girth, plant height and yield (3.71± 0.58 and 2.56±1.21 t/ha for shaded and unshaded respectively) at P < 0.05. There was significant difference in stem height of cucumber, as well as the incoming solar radiation at P < 0.05. Partial shading had minimal but positive effect on the crops. More studies are recommended to investigate total roof shading on crop performance