Abstract This study re-examined the BMN model making use of the Sigma Plot software (based on the Levenberg – Marquardt algorithm) to generate modified versions of the BMN model that are specific for Ibadan, Kano and Onne and one version which applicable across the country, correcting some perceived shortcomings of the BMN. Records of climatic variables (Solar radiation, Maximum and Minimum Temperature, Maximum and Minimum Relative Humidity and Wind speed) were collected from three Internat...
ABSTRACT Instability of a damaged pile due to a statically or dynamically applied overload is studied in this work using the finite element method. A damage parameter from such a pile is calculated using fracture mechanics concepts. The parameter is used to modify the beam element at the cracked or damaged location. Soil samples were obtained from the site of the pile and were subjected to laboratory tri-axial tests to obtain shear strength parameters c and . Other soil parameters s...
Abstract In modern greenhouses, measurements of climate conditions are required to give the grower a better understanding on how each factor affect growth and how to achieve maximal crop productiveness. The measurements and resultant optimal conditional adjustments enable the grower to improve productivity and achieve maximum costs and energy savings. Data of climate parameters were collected and analyzed to determine night and diurnal change of solar radiation, air temperature and humidity i...
ABSTRACT Product temperature is a very important system parameter as well as an indicator of extrusion proc- ess. In this study, the product temperature response of a single screw extruder developed locally was investigated for the extrusion process of the flour and starch of maize and cassava which are grown in Nigeria in large quantity but with high post-harvest losses. These were compared with wheat flour which is commonly used for the production of alimentary pastes. A factorial experimen...
ABSTRACT The increase in papaya production requires new strategies to extend the storage life of the fruit. Edible coatings act as physical barriers when applied on the surface of fruits and effectively change their internal atmosphere and delay the ripening process. In the present study, two different coatings were developed from the mucilage of Opuntia cactus and their effects were investigated on the quality and storability of papaya fruits. The two experimental coatings were pure mucilage...
Abstract Records of climatic variables (Solar radiation, Maximum and Minimum Temperature, Maximum and Minimum Relative Humidity and Wind speed) were collected from three International Institute of Tropical Agriculture (IITA) Stations namely Ibadan, Kano and Onne in Nigeria. For Ibadan, a 36-year (1973 – 2008) record was obtained, for Kano, a 29-year (1980 - 2008) record was obtained and for Onne, a 31-year (1977 - 2006) record was obtained. Evapotranspiration rates for each of the stations ...
AbstractRheological properties of food are very important indicators of the quality and texture of food products. In this study, the relative viscosity and pasting characteristics (cold and hot paste viscosity) of extrudates from a locally developed extruder (L/D 12:1, CR 4.4:1, 4 KW) were determined. The extrudates were processed from the flour and starch of cassava and maize and wheat flour. Stepwise regression and other follow up tests were employed to a factorial experiment in completely ...
Abstract The substantial amount of energy consumed during food processing and energy consumption is a very significant factor of operational costs. Also, consumption of products of starchy crops like cassava, maize and wheat is the common feature of low income dwellers of Africa. Improvement of these diets by fortifications with essential components of food including proteins, vitamins and minerals is desirable. Extrusion cooking has been proven to be a very efficient food processing technolo...
ABSTRACT In this study, the effect of extrusion process parameters of a locally developed extruder on the moisture loss of extrudates of the flour and starch of maize and cassava which are grown in Nigeria in large quantity were characterized. These were compared with those of wheat flour which is commonly used for the production of alimentary paste. The parameters considered include feed moisture (30, 40, 50 %), extruder temperature (40, 70, 100oC) built up by varying the duration of samplin...
Abstract: In this study, the effect of extrusion process parameters of a locally developed extruder on the expansion of extrudates of the flour and starch of maize and cassava which are grown in Nigeria in large quantity was characterised. These were compared with those of wheat flour which is commonly used for the production of alimentary paste. The parameters considered include feed moisture (30, 40, 50 % d.b.), extruder temperature (40, 70, 100oC) varied by continuous running of the machin...
AbstractA two-dimensional transient heat conduction equation was solved by finite- difference method to predict temperature variations within the maize (Zea mays) bin. The mathematical model comprises the center, interior and exterior heat transfer equations. Variables used include bin diameter, bin-wall material, grain temperatures, grain thermal and air properties. Software was developed for the model in Visual Basic. Temperatures within the silo were predicted at radii 0.0m (silo center), ...
In this paper, rocks with existing cracks and the effects on concrete structures it supports is discussed. Based on this paper, rock cracks may occur naturally when the rock gets closer to the earth surface due to erosion, through weathering processes (particularly frost wedging in mountainous areas and the diurnal heating and cooling of a rock outer layer in hot arid environments) and through tree roots. Artificially, cracks in rock may be caused by shock waves during rock blasting. The effe...
This paper attempts to study the mechanicalbehaviour of coconut shell aggregate (CSA) concretesubjected to elevated temperatures when coconut shell (CS)is used to replace coarse aggregate at 0, 10, 20 and 40% inconcrete. The coconut shell used was obtained by breakingthe shells into smaller sizes of less than 20mm after thefibres were removed. In order to produce control concretesamples with a minimum compressive strength of 15N/mm2at 28 days curing age, mix ratio of 1:2:4 and water-cementrat...
This paper presents the findings of an investigation into the use of mahogany leaves particles for the production of gumArabic bonded particleboards. Fresh mahogany leaves, air-dried to a target moisture content of 10% were crushed to anaverage particle size of 2mm. Mix ratios of 2:1, 2.5:1, 3:1, and 3.5:1 of gum Arabic to the crushed mahogany leaves byweight of the mahogany leaves were produced respectively. Twenty four (24) particleboards of sizes 200mm length,50mm width, and 6mm thick were...
This paper presents the findings of an investigation on the use of coconut shell ash (CSA) as admixture in concrete and its effect on durability performance. The CSA used was obtained by controlled burning of coconut shell in an incinerator to a temperature of 600–650ºC for 3 hours, air cooled, sieved through 75μm sieve and characterized by using X-ray Fluorescence (XRF) analytical method. The compressive and splitting tensile strengths of concrete were investigated at varying CSA additio...