Development of Electromagnet for Laboratory Water Treatment Experiments

Water is said to be magnetized when it flows across the magnetic field and magnetized water finds its application in many areas of life. Despite the numerous benefits of magnetized water, very little works have been reported on the development of magnet for water magnetizer application. In most of the reported works, the detailed theoretical analysis and design procedure required for the development of the magnet was not accounted for; hence the need for the present study. Electromagnetic means of producing flux density is considered in this study due to its advantage of flux density variation, which is not achievable with the use of its permanent magnet counterparts. The design equation of short electromagnet was derived from the existing equations of coil magnetic flux density and then used for the air core electromagnet design. The variation of the magnetic flux density with the distance between two electromagnets was empirically investigated. The performance of the developed electromagnet is satisfactory, as the flux density varies between 814.6 and 510G corresponding to the gap (0 - 4cm) between the coils (i.e., water pipe diameter). Keywords— Air core, Coils, Iron core, Magnetic flux density, Magnetized wate

Development of an Instrumentation System for a Laboratory Model Food Product Dryer

To achieve optimal dryer performance, the process parameters required for both the optimization and control of the drying process must be made available via the instrumentation system. A few works have been reported on the development of instrumentation systems for handling drying system parameters. Out of which, some are deficient in the number of drying process parameters that can be handled, while others are unreliable and inaccurate. Therefore, there is the need to develop a microcontroller-based instrumentation system that can monitor, measure, control, display and store the main drying process parameters and sample weight with a high degree of reliability and accuracy. In this study, the sensors were selected based on system specifications and interfaced with the microcontroller. The codes for controlling, logging and displaying of drying parameters were developed and installed on the microcontroller. When tested at steady-state conditions, the system yielded satisfactory results with maximum control and detection errors being 2.0% and 1.8% for the temperature and sample weight, respectively. The developed system can be used for efficient computation of both the dry and wet basis sample moisture content values and also detect the set sample weight. Keywords— Dryer, Drying parameters, Instrumentation system, Moisture content, Sensor

PID controller for microsatellite yaw-axis attitude control system using ITAE method

The need for effective design of satellite attitude control (SAC) subsystem for a microsatellite is imperative in order to guarantee both the quality and reliability of the data acquisition. A proportional-integral-derivative (PID) controller was proposed in this study because of its numerous advantages. The performance of PID controller can be greatly improved by adopting an integral time absolute error (ITAE) robust controller design approach. Since the system to be controlled is of the 4th order, it was approximated by its 2nd order version and then used for the controller design. Both the reduced and higher-order pre-filter transfer functions were designed and tested, in order to improve the system performance. As revealed by the results, three out of the four designed systems satisfy the design specifications; and the PD-controlled system without pre-filter transfer function was recommended out of the three systems due to its structural simplicity, which eventually enhances its digital implementation

Analytical determination of load resistance value for MQ-series gas sensors: MQ-6 as case study

The MQ-series gas sensors are attractive candidates in the area of gas concentration sensing due to their high sensitivity and low cost. Even though the sensor circuit sensitivity and sensor power dissipation level both depend on load resistance, the process of the load resistance selection has not been well researched, hence the need for this study. The derivation of model equations for determining the sensor circuit sensitivity and sensor power dissipation is presented. The derived equations were used to investigate a typical scenario of MQ-6 gas sensor under the influence of liquified petroleum gas (LPG). The variation of sensitivity with load resistance and that of power dissipation with sensor resistance were parametrically investigated. The load resistance that yields maximum sensor circuit sensitivity with the maximum sensor power dissipation less than the set threshold is the candidate resistance for the sensor circuit. The 20 kΩ load resistance recommended for MQ-6 in the datasheet was authenticated in this study, yielding the maximum possible sensor circuit sensitivity and tolerable sensor power dissipation of 0.195 mV/ppm and 3.125×10−4 W, respectively

Yield loss caused by Coryna hermanniae Fabricius (Coleoptera: Meloidae) on pearl millet in Nigeria

In 1997, field trials were conducted in Nigeria to determine pearl millet grain yield losses caused by C. hermanniae under free-choice and no-choice conditions. Head cages were used to artifically infest panicles with 5, 10, 15, 20, 25 or 30 C. hermanniae adults per panicle for 3 weeks from the beginning of flowering. Panicle weight at maturity declined from 43 g/25 cm panicle length in the control by 14.9% with 5 beetles per panicle to a decrease of 63% with 30 beetles per panicle. Grain yield decreased from 30 g/25 cm panicle length by 75% with 30 beetles per panicle. Yield loss on naturally infested panicles was calculated to be 19%. These results support the hypothesis that C. hermanniae is a potentially serious pest of pearl millet in West Africa

N-nitrosodiethylamine induced redox imbalance in rat liver: Protective role of polyphenolic extract of Blighia sapida arilli

a b s t r a c t Aim: This study investigates the reactive oxygen species detoxification potentials of polyphenolic extract of Blighia sapida arilli in the liver of N-nitrosodiethylamine-treated rats. Methods: Male rats, weighing 158 AE 2.9 g were completely randomized into 7 groups (AeG) of five rats each. Rats in C, D, E and F were administered orally once daily at 24 h interval for 7 days with 1000, 250, 500 and 1000 mg/kg body weight of polyphenolic extract of B. sapida arilli respectively. Group G was given 100 mg/kg body weight of vitamin C. On the sixth day, group B, D, E, F and G were administered with 100 mg/kg body weight N-nitrosodiethylamine (NDEA). Group A, which served as the control was treated like the test groups except, that the animals received distilled water only. Results: Reactive oxygen species detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase) activities were significantly (P < 0.05) induced by B. sapida arilli. These inductions significantly (P < 0.05) attenuated the decrease in reactive oxygen species detoxifying enzymes mediated by NDEA treatment and compared favourably with vitamin C. NDEA-mediated elevation in the concentrations of oxidative stress biomarkers; malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl and percentage DNA fragmentation were significantly (P < 0.05) lowered by polyphenolic extract of B. sapida arilli. Conclusion: Overall, the results obtained from this study revealed that the polyphenolic extract from B. sapida arilli enhanced the detoxification of reactive oxygen species in NDEA-treated rats. The polyphenols also prevented the peroxidation of lipid, oxidation of proteins as well as fragmentation of DNA component in the liver of rats and hence gave the evidence of possible prophylactic potentials of B. sapida arilli

Dauro millet germplasm collection in Nigeria

A collection trip was conducted in 1997 in Nigeria to determine the economic importance of the photoperiod-sensitive dauro pearl millet (Pennisetum glaucum) type, its role in the diet of people in the production areas, and its potential for improving local pearl millet landraces in Nigeria. The differences between dauro and maiwa types, and the agronomy, constraints to production, pests and geographical distribution of dauro are discussed

Prevalence and Characterization of Salmonella Isolates from Poultry Farms in Ilorin, Nigeria

Poultry birds are very important source of essential proteins in developing countries, but also play an important role in transmission of Salmonella to human and nonhuman. Exposure to this pathogen also occurs through use of poultry droppings as manure for crop and vegetable production. This study investigated prevalence of Salmonella in feces of poultry farms in Ilorin, Nigeria. Salmonella isolated were further characterized by molecular method. Fecal samples were cultured in pre-enrichment medium, Selenite F medium and finally sub-cultured on Salmonella-Shigella agar. None lactose fermenting colonies with black center were picked for presumptive identification using biochemical tests and confirmed by serological test by method previously described. Molecular characterization was carried out using 16S rRNA gene sequencing following standard procedure. Out of 170 samples collected and examined, 8 (4.7%) gave biochemical characteristics that resembled Salmonella, but only 6 (3.5%) were confirmed as Salmonella by polyvalent antisera. Molecular characterization revealed that serovars isolated were Salmonella Enteritidis 3 (1.8%) and Salmonella Paratyphi 3 (1.8%). Phylogenetic tree constructed by neighbor-joining method as derived from analysis of the 16S rRNA gene sequences showed close relationship to Salmonella Paratyphi strain FB0015 16S ribosoma RNA gene partial sequence to our Salmonella Paratyphi isolates. The detection of 3.5% prevalence rate of Salmonella serovar from feces of laying poultry birds my serve as potential source of transmission of this pathogen to human through chicken meat, egg or use of poultry dropping as manure in crop or vegetable production

Numerical Simulation of Axisymmetric and Asymmetric Extrusion Process Using Finite Element Method

The deformation load is the most important parameter in the press design. The flow of metal, consequently load, is largely influenced by the geometry of the die and hence the geometric shape of the tools is the main factor by which an optimum load can be developed. In extrusion process the strain distribution, resulting from deformation load, and other important variables that influence material structure, such as a hydrostatic stress, are strongly dependent on the geometry of the die. In the present investigation using linearly converging die profiles, the extrusion of simple and advanced polygons such as circular, square, triangular, hexagonal, heptagonal, octagonal, L-, T-, and H- sections from round billet have been numerically simulated. Mathematical equations describing the die profiles were evaluated. A solid CAD model for the linearly converging die profile was made using Autodesk Inventor 2013 software and numerical analysis using DEFORM 3D software for extrusion of the above sections from round billet was then performed to determined, for dry and lubricated condition, the load prediction, effective stress, effective strain, strain rate, velocity and temperature distribution during the deformation. It is found that the predictive loads for advance (asymmetric) shapes are found to be higher than that of the simple shapes. While there is no marked difference between the predictive load for simple (axisymmetric) shapes, the L-section has the highest extrusion load, followed by T-section and the H-section given the least pressure

Profitability of Watermelon to Farmers in Ibarapa Central Local Government Area of Oyo State

The study analyzed the profitability of watermelon as an alternative crop to the melon the farmers in Ibarapa Central Local Government Area of Oyo state, Nigeria are used to grow traditionally. Unfortunately, melon had remained a poor marketing commodity over a long period of time due to price fluctuation. Data collected were analyzed using descriptive statistics and gross margin. Budgetary analysis revealed a profitability of watermelon with gross margin of ₦2.18 is realized for every ₦1 invest on watermelon per hectare. The result of the analysis also showed that total cost was N3254250 and the total revenue was N7109600. This gave a gross margin of N3855350 of watermelon produced it therefore recommended that the local government should acquire more tractors for hiring to the farmers while subsidy is required in other to reduce the cost of land clearing. Finally, government should as a matter of urgency make credit facilities and fertilizer available to farmer, grade and open up more road network that will facilitating easy transportation of farm produce and reduce cost of transportatio