Effects of internal heat generation, thermal radiation, and buoyancy force on boundary layer over a vertical plate with a convective boundary condition

In this paper we analyze the effects of internal heat generation, thermal radiation, and buoyancy force on the laminar boundary layer about a vertical plate in a uniform stream of fluid under a convective surface boundary condition. In the analysis, we assumed that left surface of the plate is in contact with a hot fluid while a stream of cold fluid flows steadily over the right surface with a heat source that decays exponentially. Similarity variable method is applied to the governing non-linear partial differential equations. The transformed into a set of coupled nonlinear ordinary differential equations are solved numerically by applying shooting iteration technique together with fourth order Runge-Kutta integration scheme. The effects of Prandtl number, local Biot number, the internal heat generation parameter, thermal radiation, and the local Grashof number on the velocity and temperature profiles are illustrated and interpreted in physical terms. A comparison with previously published results in special case of the problem shows an excellent agreement

A Sociolinguistic Approach to Security Challenges and Sustainable National Development in Nigeria

The study is a sociolinguistic approach to solving security challenges and enhancing sustainable national development in Nigeria. It argues that language and society influences each other and as such language could be used to solve societal problems. In doing so, the paper x-rays the functions of language in human society as propounded by Halliday and Stubbs. It discusses the multilingual nature of Nigeria, the concept of national development as well as security challenges facing the country. The paper notes that the dominant use English language against the indigenous languages in nearly all communicative domains in Nigeria has failed the nation in its bid to overcome numerous security threats. This may not be unconnected with the low literacy level in the country. As a result, the paper recommends a tripartite language policy vis-à-vis the use of English language, the indigenous languages as well as the Nigerian Pidgin depending on the contextual demand. The paper also advocates the adoption of more indigenous languages, apart from the three major ones- Hausa, Igbo and Yoruba, for use. This will imply a revision of Nigeria's language policy and the constitutional provisions on language

The Home as Workplace: Investigating Home Based Enterprises in Low Income Settlements of the Lagos Metropolis

The paper critically examines the phenomenon of Home Based Enterprises (HBE‘s) in low income residential areas of the Lagos Metropolis. The research adopts a purposive selection of thirty one low income residential neighbourhoods in the Lagos Metropolis. Data was obtained by the administration of structured questionnaires and analysis was done by both parametric and non-parametric methods. Random sampling of 394 home based enterprises was carried out. Issues examined include housing and environmental conditions; nature as well as types of home based enterprises and socioeconomic characteristics of operators. These include age, gender, and income, household size and level of education. The social network and informal institutions as well as the urban planning implications of these HBEs were also considered. The research revealed the importance of home based enterprises as a major source of income generation and socialization in urban areas. Recommendations include the adoption of case-specific planning models, consideration of cultural contexts in planning and the adoption of local economic development strategies in city design and development.Key words: Poverty, Income, Lagos, Home, Workplace, HBEs, LE

Interrelationship between Body Weight and Body Size Parameters in Chinchilla and New Zealand White Rabbit Genotypes in Abeokuta, Nigeria

Traits of economic importance in rabbit when measured provide attributes that may be used as selection criteria by livestock breeders. This study was carried out to determine the interrelationship between body weight and body size parameters and to develop linear equations for predicting body weight using some body size parameters in two rabbit genotypes. Chinchilla and New Zealand White rabbit genotypes were selected for this study, with each breed having 20 does and 4 bucks making a total of 48 rabbits (precisely breeders). The animals were intensively managed and body weight, body length, ear length, heart girth, head length and tail length were measured on weekly basis. Body size parameters were correlated and regressed with body weight of each genotype and results were compared. At the end of the twelve-week study period, body weights were 2.074±0.280 kg and 2.130±0.240 kg for Chinchilla and New Zealand White rabbit genotypes, respectively. Body size parameters considered were positively correlated with body weight for both genotypes. Ear length, heart girth and head length only were significantly (P < 0.01) correlated with body weight for Chinchilla, while body size parameters were found to be significantly (P < 0.01) correlated with body weight for New Zealand White rabbit. Linear equations were developed for predicting the body weight from these body size parameters in each genotype. We observed that heart girth proved to be the best predictor for body weight in New Zealand White and Chinchilla rabbit genotypes, having a coefficient of determination (r²) of 0.529 and 0.547, respectively. Keywords: Body dimensions, Breeds of rabbit, Bucks, Does, Prediction, Selection criteri

Scientific Technology Development a Necessary Tool for Promotion of Organic Agriculture in Africa: A Case Study of Scientists in Organic Agriculture in the South Western Nigeria

Appropriate technology development and transfer are fundamental to the promotion of organic agriculture (OA) as mitigation to climate change and food insecurity. The broader benefits of organic farming and agro-ecology often go unrecognized or are simply ignored due to lack of enough research evidences and technology development. This study assessed the technology developed by scientists, motivational factors and the challenges of technology development for the promotion of organic agriculture in Nigeria. This study was carried out in the South Western region of Nigeria. Within the zone are the majority of the scientists involved in the organic agriculture movements in Nigeria. From the available data 30% of the members were randomly selected; with the sample size of 65 respondents. Primary data were collected with a well structured questionnaire from the respondents. The data were analyzed using frequency distribution, percentage, and Person Product Moment Correlation (PPMC). The study revealed that interest in organic agriculture, and health and environmental concern ranked high as motivational factors for technology development. Among the technologies developed and transferred to farmers are composting technique (22.6%), planned crop rotation (11.2%), while disease management (4.8%) and storage techniques (3.2%) recorded low transfer. Low funding and inadequate exposure to organic farming techniques were ranked high as serious challenges to technology development. There was significant correlation between motivational factors and technology development (r = 0.277, p = 0.029). This study concluded that, health and environmental safety is a major factor that motivate to develop technology but funding and inadequate exposure to organic farming techniques are serious challenges to develop scientific technology for promotion of OA

The influence of the combined microwave power and hot air ventilation on the drying kinetics and colour quality of tomato slices

Tomato is one of the most important fruit used as an ingredient in different foods in food processing and preparation. Fresh tomato consists of about 91% of moisture. Tomato has to pass through all three rates of drying (constant, first and second falling rate period) during drying, using hot air ventilation, and requires prolonged time with much of quality changes. In this study, microwave assisted hot air ventilation drying of tomato slices had been considered. Microwave oven working at 2450 MHz, using different power densities (1, 2 and 3 W g-1) was combined with hot air ventilation at 50°C and hot air ventilation drying without microwave power at 40, 50, 70 and 80°C to dry tomato slices down to 10% moisture content. The drying characteristic curve was analyzed to determine the drying time. The tomato slice sample dried faster when subjected to microwave heating, coupled with hot air ventilation at 50°C. The drying times required for tomato slices to reach 10% moisture content were found to be 3.2, 2.5 and 1.3 h, using 1, 2 and 3 W g-1 microwave power densities, coupled with 50°C hot air ventilation, respectively. On the other hand, the drying time of tomato slices to 10% moisture content required 20.5, 13.1, 9.6, 6.8 h for drying at 40, 50, 70 and 80°C, using hot air ventilation without supplementing heating with microwave power. Microwave drying maintained the superior colour of tomato slices after drying period, compared to the other treatments.Key words: Microwave, tomato slice, drying equation, colour, drying rate, moisture content

Comparative Assessment of Rural Development Programs of Selected NGOs in Plateau State, North-Central, Nigeria

The study examined the extent to which the rural development programs of Evangelical Church of West Africa-People Oriented Development (ECWA-POD) and Country Women Association of Nigeria (COWAN) contribute to the development of rural communities in Plateau State. A comparison of the non-governmental organizations (NGOs) was done to examine the factors that explain variation in the organizations. A total of 150 respondents made up of community members and staff of the organizations randomly selected from four Local Government Areas responded to the structured questionnaire. The data were analyzed using descriptive and inferential statistics. The study revealed that the major rural development programs of the NGOs were agricultural programs, health programs, human resource development, community development, and industrial and trade promotion programs. Analysis carried out showed a significant relationship (P 2=0.023; p#0.05) in the program orientation of the two organizations. Majority (57.8 percent for ECWA-POD and 75.6 percent for COWAN) of the respondents considered the programs of the organizations as beneficial and benefitted more concerning potable water and community sanitation facilities. Participation of the community members at various stages of the program and type of participation was also identified. The perceived level of goal attainment of the organization was higher (t=2.72; p#0.05) in COWAN than ECWA-POD. It was recommended that government should collaborate with NGOs through the Agricultural Transformation Agenda (ATA) concerning project identification, design, and implementation of rural development programs

Further Results on the Effects of Variable Viscosity and Magnetic Field on Flow and Heat Transfer to a Continuous Flat Plate in the Presence of Heat Generation and Radiation with a Convective Boundary Condition

The steady, laminar boundary layer flow with a convective boundary condition, to a continuously moving flat plate is studied taking into account the variation of viscosity with temperature in the presence of a magnetic field, heat gen-eration and thermal radiation. The fluid viscosity is assumed to vary as a linear function of temperature. The resulting, gov-erning equations are non-dimensionalized and transformed using a similarity transformation and then solved numerically by sixth order Runge-Kutta method alongside with shooting method. Comparison with previously published work is performed and there was a perfect agreement at large value of the Biot number. A parametric study of all the embedded flow parameters involved is conducted, and a representative set of numerical results for the velocity and temperature profiles as well as the skin-friction parameter and the Nusselt number is illustrated graphically to show typical trend of the solutions. It is worth pointing out that, when the variation of viscosity with temperature is strong in the presence of the effect of a magnetic field, radiation, heat generation, the results of the present work are completely different from those that studied the same problem in the absence of magnetic field, thermal radiation and the heat generation. It is interesting to note that higher the values of Prandtl number lesser the effects of Biot number and the magnetic field intensit

Effect of variable uid properties and nth order of chemical reaction on MHD boundary layer ow of upper convected Maxwell fluid past a vertical surface in a doubly stratified porous medium

Paper presented at the 5th Strathmore International Mathematics Conference (SIMC 2019), 12 - 16 August 2019, Strathmore University, Nairobi, KenyaThe ow of temperature dependent viscosity and thermal conductivity of free convective MHD upper convected Maxwell uid over a surface with stratification and nth order of chemical reaction is considered. It is assumed that buoyancy forces induce a free convection boundary layer in which the heated fluid rises vertically. The governing partial differential equations are transformed into non-linear ordinary differential equation by introducing suitable similarity variables and the approximate analytical solution is obtained through Homotopy Analysis Method. The effect of some pertinent parameters like Deborah number, stratication, chemical reaction, and variable thermophysical parameters are presented on velocity, temperature, concentration distributions to illustrate the details of ow of heat and mass transfer characteristics. It is observed that for the case of n = 1&2, the concentration of species reduces for increasing chemical reaction parameter. It is also noticed that, the values of f" (0) decreases while '(0) and ᴓ(0) increases with increasing Deborah number βDepartment of Mathematics and Statistics, Federal University Wukari, Tamba State,Nigeria. Department of Mathematical Sciences, Federal University of Technology, Akure, Nigeria

Adsorption and corrosion inhibition properties of thiocarbanilide on the electrochemical behavior of high carbon steel in dilute acid solutions

The inhibition performance of thiocarbanilide on the electrochemical corrosion behavior of high carbon steel in 1 M H2SO4 and HCl acid solutions was studied through weight loss method and potentiodynamic polarization test. Data obtained showed that the organic compound performed effectively in acid solutions at all concentrations with an average thiocarbanilide inhibition efficiency above 70% in H2SO4 acid and 80% in HCl acid from weight loss and potentiodynamic polarization test respectively. Results from corrosion thermodynamic calculations showed that the adsorption of thiocarbanilide onto the steel was through chemisorption mechanism whereby the redox electrochemical process responsible for corrosion and the electrolytic transport of corrosive anions were simultaneously suppressed. Statistical derivations through ANOVA analysis confirm that the influences of both the inhibitor concentration and exposure time on inhibition efficiency values are negligible. Adsorption of the compound was determined to obey the Langmuir and Frumkin isotherm mode