EFFECT OF GOEMETRY ON THE ANALYSIS OF THERMAL EXPLOSION OF A STRONGLY EXOTHERMIC CHEMICAL REACTONS

This study is devoted to investigate the effect of geometry on thermal explosion of a strong exothermic chemical reaction with variable pre-exponential factor under Bimolecular, Arrhenius and Sensitised reaction rate, neglecting the consumption of the material are examined. Analytical solutions are constructed for the governing nonlinear boundary-value problem using perturbation technique together with a special type Hermite-pade approximation and important properties of the temperature field including bifurcations and thermal criticality are discussed. It is shown that temperature field is highly influenced by the geometry

Effect of Financial Liberalization on the Performance of Informal Capital Market

This study examines the effects of financial liberalization on the corporate performance of informal capital market in Nigeria {Unity (IFE) NUT Cooperative Investment and Credit Society as a case study}. It employs the Ordinary Least Square method of multiple regression analysis for the period of ten years (2001-2010). Three models were formulated, the first, proxied financial liberalization variable (saving rate) with loan granted by informal capital market in Nigeria and saving mobilized by the market. The second, revealing a relationship between financial liberalization variable (lending rate) with deposit mobilised by informal capital market in Nigeria and loan granted by the market while the last, depicting relationship between financial liberalization variables (saving and lending rates), deposit mobilised with loan granted by informal capital market in Nigeria and net surplus of the market (being non-profit making institutions). This work concluded that financial liberalization has significant effect on deposit mobilised and loan granted by the market but did not have significant effect on their net surplus. It therefore, recommends that the market should be supervised, formulate policies that would enhance the performance of informal financial sector in Nigeria coupled with the reduction of the gap between lending and saving rates of banks. Keywords: Financial Liberalization, Informal Capital Market, Unity (IFE) NUT Cooperative Investment and Credit Society, Ordinary Least Square (OLS) Metho

Facile Synthesis, Characterization and Antimicrobial Activity of 2-Alkanamino Benzimidazole Derivatives

Benzimidazole derivatives are known to represent a class of medicinally important compounds which are extensively used in drug design and catalysis. A series of 2-substituted benzimidazole derivatives 10a-i was herein synthesized from the reaction of o-phenylenediamine with some amino acids using ameliorable pathway. The chemical structures of the synthesized compounds were con rmed by IR, UV, 1H-NMR, 13C-NMR, Mass spectral and analytical data. The compounds were investigated for their antimicrobial activity alongside gentamicin clinical standard. The results showed that this skeletal framework exhibited marked potency as antimicrobial agents. The most active compound was 1H-benzo[d]imidazol-2-yl)methanamine, 10a

Performance evaluation of wind turbines for energy generation in Niger Delta, Nigeria

This paper evaluates wind energy potentials of seven selected locations spreading across Niger-Delta region of Nigeria using wind speed data that extend over 9 to 37 years and subjected to 2-parameter Weibull distribution functions. The performance of four wind turbine models ranging from 35 to 500 kW was simulated in all the locations considered. The results show that the performance of all the wind energy conversion systems gave the least energy output values at Ikom. In addition, annual energy output ranged from 4.07 MWh at Ikom to 145.57 MWh at Ogoja with Polaris America (100 kW) and Zeus Energy (500 kW) wind turbines respectively. It was also observed that, irrespective of the site, G-3120 (35 kW) wind turbine has the highest capacity factor among the models considered. Therefore, for wind energy development, G-3120 model or wind turbine with similar rated wind speed would be most suitable in all the locations. The number of inhabitants that can be served by the energy produced using G-3120 turbine in each location was estimated

Solar energy applications and development in Nigeria: Drivers and barriers

In this study,current perspectives of solar energy utilization as a renewable energy option in Nigeria are examined and discussed from the stand point of sustainable development.The country being a world crude oil and natural gas producer,is over-dependent on the seenergy sourcesforelectricitygeneration and otherenergyapplications.Thishascurrentlyputthecountryatariskofimpendingenergycrisesin view ofthefastdiminishingfossilreserves,inadequaterefining capacitytomeetdomesticconsumption and seriouscasesofenergyinsecurityinrestiveregionswhereexploitationsexist.Inspiteofthevast fossil basedenergyreserves,ameagerelectricityproductioncapacitythatisputat4517.6MWasat December 2012isgeneratedtosupporttheeconomyofateemingpopulationofapproximately170 million people.Nigeriaisnaturallyendowedwithabundantdepositofrenewableenergyresourcesof which solarenergyfromtheSun(beingtheworld0s mostabundantandpermanentenergysource)has for decadesbeenenjoyingveryhighlevelutilizationbyruraldwellersforagriculturalprocessingsinthe country.Itisvastlydepositedwithanestimated17,459,215.2millionMJ/day of solar energy falling on the country0s 923,768km2 land area(approximaterangeof12.6MJ/m2/day in the coastal region to about 25.2 MJ/m2/day in the far north). The different applications to which solar resources have been put and the extent of utilization(including details of existing projects)in the country were thoroughly investigated and discussed.The possible motivations for extensive development of solar energy conversion systems in Nigeria area l so discussed and some of the barriers and challenges are presented. Step sand policy measures to over come the barriers and facilitates the utilization of this resource are suggeste

Generation of a typical meteorological year for north–east, Nigeria

The Finkelstein–Schafer statistical method was applied to analyze a 34-year period (1975–2008) hourly measured weather data which includes global solar radiation, dry bulb temperatures, precipitation, relative humidity and wind speed in order to generate typical meteorological year (TMY) for five locations spreading across north–east zone, Nigeria. The selection criteria are based on solar radiation together with the dry bulb temperature values and representative typical meteorological months (TMMs) were selected by choosing the one with the smallest deviation from the long-term cumulative distribution function. A close-fit agreement is observed between the generated TMY and long-term averages. The TMY generated will be very useful for optimal design and performance evaluation of solar energy conversion systems, heating, ventilation, and air conditioning (HVAC) and other solar energy dependent systems to be located in this part of Nigeri

Physicochemical and Heavy Metals Characteristics of Soil from Three Major Dumpsites in Ilorin Metrpolis, North Central Nigeria

Impact of waste disposal and management is a worldwide phenomenon leading to health impact most especially in underdeveloped and developing world. This study was undertaken to assess the major contaminants in some municipal waste disposal sites and the prospective impact to the surrounding domestic water supply source as well as the impact on the health of the people in the city. This is carried out by studying variousphysico-chemical parameters of soil which were collected from three municipal dump locations namely; Ita-Amodu, Sawmill garage and Kuntu areas in Ilorin metropolis, Kwara State Nigeria. The geochemistry of the dumpsites were studied with respect to important parameters such as pH, electrical conductivity, temperature, sulphates, chlorides, nitrates, moisture content, organic matter and heavy metals having the following constituents present in its composition- Cadmium (Cd), Lead (Pb), Zinc (Zn), Iron (Fe), and Copper (Cu). The study revealed that the three different soils samples: “(A) Ita-Amodu”, “(B) Sawmill Garage”, and “(C) Kuntu”) have pH of 7.1, 7.2 and 6.8, respectively. Temperature of 24.2, 26.4, and 28.0 oC, Organic matter compositions of 0.95%, 0.73%, and 1.14%. The Moisture contents were 3.93%, 2.89%, and 3.48% respectively. The chloride  contents of the samples was found to be 31.76 mg/L, 48.98 mg/L, and 91.63 mg/L, while nitrates were found to be 0.10 mg/L, 0.06, mg/L and 0.23mg/L, with a sulphate values of 1.96 mg/L, 2.35 mg/L, and 2.14 mg/L. The conductivities were 1.79 μs/cm, 2.23 μs/cm, and 1.15 μs/cm respectively. Heavy metal analysis from the waste soil were found to contained copper (Cu) - 0.03 mg/L, 0.028 mg/L, and 0.031 mg/L, zinc (Zn) - 0.04, mg/L 0.009 mg/L, and 0.066 mg/L), cadmium (Cd) - 0.516 mg/L, 0.62, mg/L and 0.048 mg/L), Lead (Pb) - 0.063 mg/L, 0.07 mg/L, and 0.056 mg/L), and iron (Fe) -0.518 mg/L, 0.62 mg/L, and 0.190 mg/L. Keywords: Dumpsites, Heavy metals, Ilorin, Moisture contents, Nitrates

Heat and Mass Transfer for Soret and Dufour’s Effect on Mixed Convection Boundary Layer Flow over a Stretching Vertical Surface in a Porous Medium Filled with a Viscoelastic Fluid in the Presence of Magnetic field

Thermal-diffusion and diffusion-thermo effects on combined heat and mass transfer on mixed convection boundary layer flow over a stretching vertical surface in a porous medium filled with a viscoelastic fluid in the presence of magnetic field is investigated. The partial differential equations governing the problem have been transformed by a similarity transformation into a system of ordinary differential equations which are solved numerically by using the shooting method with sixth-order of Runge-Kutta technique which are compared with Homotopy Adomian’s Decomposition Method (HAM) for special case when magnetic field parameter is zero For fluids of medium molecular weight (H2, air), profiles of the dimensionless velocity, temperature and concentration distributions are shown graphically for various values of parameters embedded in the flow model. Finally, numerical values of physical quantities, such as the local skin friction coefficient, the local Nusselt number and the local Sherwood number are presented in tabular form

Examination of Students’ Academic Performance in Selected Mechanical Engineering Courses Prior-to-and-During COVID-19 Era

Advances in Information and Communications Technology (ICT) as well as the present challenges of COVID-19 have led to a new paradigm causing an absolute or partial transition from in-person classroom teaching-learning to online. There is little information available on research efforts that investigated the impact of an online learning approach on the academic performance of students in mechanical engineering-based courses. Therefore, the objective of this paper is the impact study of online learning mode as compared to in-person on academic performance of students in selected mechanical engineering courses in one of the Universities in South Pacific Islands prior-to-and-during COVID-19 Era. Data on grades obtained for 178 students that offered Fluid Mechanics, Thermodynamics, Heat Transfer, and Advanced Thermofluids (FTHA) courses were subjected to descriptive and non-parametric (Mann-Whitney and Kruskal-Wallis) statistical tests. Although descriptive analysis showed that online mode of instruction might influence a better academic performance in FTHA courses in comparison with in-person mode of instruction, the outcome of Mann-Whitney U and Kruskal-Wallis tests at specific p-values and corresponding z-values generally exhibited p-values higher than of 0.05, implying insignificant difference in performance between the two modes of learning investigated. Though the non-parametric statistical test results showed there was no significant difference in academic performance of students when online and in-person modes of learning were used, this, however, does not imply that a difference does not exist at all. Although the difference may be very trivial, descriptive analysis has shown that the online learning mode has at least exhibited better students’ academic performance when compared to in-person. It can be inferred from the foregoing that the online learning mode does not yield a negative response in respect of the performance of students who offered all four mechanical engineering courses. Based on the findings of this study, online is considered a reliable alternative to in-person or at least a suitable complement to in-person in the in-person-online hybrid mode during the ongoing COVID-19 era and other inevitable constraints in the future. Doi: 10.28991/esj-2022-SPER-017 Full Text: PD