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DESIGN AND IMPLEMENTATION OF A BALANCED THREE-PHASE POWER PROTECTION SYSTEM
Get PDFThis work considers the design and implementation of a balanced three-phase power protection system used to load sharing formula at consumer receiving end to ensure uniform distribution of the available threephase voltage supply-source. Various methods have been developed with the main objective to provide an engineering solution to the effects causing unbalanced three-phase voltage supply. The engineering solution considered in this research work was designed and implemented with the use of local raw materials in Nigeria. This solution is thus achieved by employing voltage-tap changing technique at both primary and secondary sides of the three-phase transformer. The transformer is auto-winding star connected type where its star point is taken as system design-neutral point. However, whether the unbalanced voltage is due to an unbalanced single phase loading or unstable network supply within the plant, this system can continuously correct and adjust the correction level as required to ±0.4% of the set nominal voltage, and zero the voltage imbalances to give out 100% balanced voltage. 
RESPONSE AND PERFORMANCE OF MAIZE (Zea mays) TO SOIL AMENDMENT IN ASABA, DELTA STATE, NIGERIA
Get PDFResponse of maize to soil amendment was carried out in degraded oxisol of Asaba, Delta State Nigeria using early OBA super 2 hybrid maize. This was planted in July and harvested in September during the 2016 and 2017 cropping seasons at the Agronomy Teaching and Research Farm, Delta State University, Asaba Campus. Four levels of poultry droppings and 200 kg-1 of NPK 20:10:10 were applied in a randomized complete block design (RCBD) and, replicated three times. Growth parameters assessed were plant height, leaf area and plant girth while stover, weight of 1000 grains and grain yield were measured at harvest. Soil chemical properties were determined during the second season harvest. Data was subjected to analysis of variance and means were separated with Duncan’s Multiple Range Test (DMRT) at 5% level of probability using the …(name of software used). Results showed that NPK 20:10:10 had the best in first season but second season, poultry droppings at 10.0 t ha-1 had the best and was significantly higher than NPK 20:10:10 in leaf area, plant girth and stover yield but not significantly higher in plant height,1000 grains weight and grain yield. This further improved the potential of poultry droppings for sustainable production than NPK 20:10:10. The study confirmed that poultry droppings could be an alternative source of plant nutrients on sustainable production bases on degraded acidic oxisols
STOMACH CONTENTS AND INDEX OF FOOD SIGNIFICANCE OF OREOCHROMIS NILOTICUS (L.) IN KIRI RESERVOIR, SHELLENG, ADAMAWA STATE, NIGERIA
Get PDFStudies on natural feeding of fish to identify the trophic relationships present in aquatic ecosystems, identifying feeding composition, structure and stability of food webs was carried out. The study was designed to generate a baseline information on the food and feeding habits of Oreochromis niloticus, in Kiri reservoir, Shelleng LGA, Adamawa State, Nigeria. Sampling was done twice in a month for a period of six months from May to October 2015. On the landing site, fish specimen were randomly sorted and identified using keys. In the laboratory, each specimen was dissected using a pair of scissors to remove the gut. The entire stomach of the fish was removed and graded according to fullness. Stomach contents was sorted into categories and analyzed using Relative Frequency (RF) and point’s method. % RF and % PP (Percentage of total Points) was then used to determine the Index of Food Significance IFS. The major food items in terms of frequency of occurrence were Pithopora (55.71%), while insect parts has the lowest frequency of occurrence with 15.70%. The Index Food Significance (IFS) of O. niloticus showed that Filamentous Algae and Colonial Green Algae are the secondary diet of the fish species in Kiri Reservoir, with Cladophora (IFS= 1.04%) Pithopora (IFS=1.06%) and Volvox (IFS=1.45%), Green Algae, Cyanobacteria and Diatom are among the incidental diet, with an IFS <0.1%. This report revealed the food of O. niloticus composed mainly of plant origin; this could help in important measure towards the data needed to create a food web in Kiri reservoir
ASSESSMENT OF HEAVY METALS IN CHROMOLAENA ODORATA (L.) AROUND A DUMPSITE IN IBADAN, SOUTH WESTERN NIGERIA
Get PDFHeavy metal contamination has become a critical environmental concern and poses a serious threat to the environment leading to hazardous health effect as they enter food chain. One of the main processes of human exposure to heavy metal through the food chain is transfer of nutrients from the soil to the plants. This study assessed heavy metal concentrations in Chromolaena odorata and the soils around Lapite dumpsite in Ibadan. Five C. Odorata samples (root, stem, leaf) each were taken from control, contaminated and waste dump sites considered in this study. Composite soil samples were collected from the topsoil (0-20m) around each of thesite. Inductively Coupled Plasma- Atomic Emission Spectrometry (ICP-AES) instrumentation technique was used to determine the heavy metals (iron (Fe), zinc (Zn), lead (Pb), copper (Cu), nickel (Ni), cadmium (Cd), chromium (Cr), cobalt (Co) and Arsenic (AS) in soil samples and C. odorata tissues. These results showed that C. odorata and soil samples had significantly high levels of heavy metals in waste dump and contaminated sites than control site. Heavy metal concentrations in C. odorata and soil samples showed decreasing order ofFe> Zn> Cu> Pb> Ni> Co> Cr>Cd>As. The ability of C. Odorata to accumulate the metals was consistent with the high translocation ratio values of more than 1 and the low transfer factor values of less than 1.Heavy metals in soils showed positive correlation coefficient of 0.46-0.99 with the levels in C. Odorata plants. This study has shown the ability of C. Odorata plant to bio-accumulate translocate heavy metals. 
UNSTEADY MHD COUETTE FLOW BETWEEN TWO PARALLEL HORIZONTAL POROUS PLATES IN AN INCLINED MAGNETIC FIELD
Get PDFIn this paper, the study of unsteady Magnetohydrodynamic (MHD) couette flow between two parallel horizontal porous plates in an inclined magnetic field was carried out. The momentum and energy equations are written in a dimensionless form using the imensionless parameters. Variable separable technique was employed to solve the velocity profile and temperature distribution. However, out of many results, we conclude that, at high Hartmann number Ha, the velocity u of the fluid decreases. When the magnetic field is high, it reduces the energy loss through the plates
GROUNDWATER QUALITY ASSESSMENT AROUND IGBATORO DUMP YARD USING GEOSPATIAL TECHNOLOGY
Get PDFThis study evaluated the degree of groundwater pollution near the dump yard at Igbatoro, Ondo State. The entire study area was digitized and georeferenced in order to produce pollution maps from results obtained. Forty-five (45) water samples were obtained from fifteen (15) different locations at distances ranging from 50 m to 150 m around the refuge dump. The coordinate of the sample collection points were acquired using handheld GPS. Samples recovered were taken to the laboratory in an air tight plastic container where the physcio-chemical characteristics and other parameters needed for the computation of Water Quality Index (WQI) was calculated. Some parameters evaluated includes but not limited to the followings: dissolve oxygen (DO), total suspended solid (TSS), pH, total dissolved solid (TDS), turbidity, concentration of nitrate and nitrite, chloride, phosphate, total coliform count, and heavy metals including iron, lead, copper, cadmium, and zinc. Results obtained were compared with WHO standards for drinking water and was also used for calculating WQI for the study area. The result showed that WQI in the area ranged from 41.394 – 59.515 (50 m), 58.840 – 66.556 (100 m) and 71.111 – 85.384 (150 m). The water quality range from bad (50 m) to good (150 m) i.e. the quality of the water improved as the distance away from the dump yard increased. Other parameters investigated also had values higher than the permissible limits recommended by WHO. 
FACTORS INFLUENCING CHOICE OF CONSTRUCTION PROCUREMENT METHODS AND ASSOCIATED RISK
Get PDFThis research paper examines the procurement methods and associated risks with a view to enhancing the delivery of construction projects in Nigeria. The target population of the study were contractors, architects, quantity surveyors and construction clients as they are the stakeholders frequently involved in the construction procurement. The study explored purposive sampling to administer 40 questionnaires each to construction clients, architects, quantity surveyors and 60 to contractors respectively. 131 copies of questionnaire which was 77.06 % response were returned and found useful. Both descriptive and inferential techniques were used toanalyze the data. The results revealed that: speed in completion of projects and flexibility of the projects were the factors influencing the choice of traditional method of procurement while cost overrun and opportunity of sharing of risk between client and contractor were the risks associated with the method. Complexity of the project and the possibility of delivery to time were most important factors influencing the selection of design and build procurement method while high cost of construction, lack of competition, expensive bidding process were the risk associated with the method. 
GEOENVIRONMENTAL ASSESSMENT OF TOTAL PETROLEUM HYDROCARBON CONTENT IN OLOGBO FIELD, NIGER DELTA, NIGERIA
Get PDFHydrocarbon contamination is a common phenomenon associated with oil and gas exploitation in the Niger Delta area of south-south geopolitical region of Nigeria. The aim of this paper is to assess the geoenvironmental impact of hydrocarbon spill in Ologbo area of Edo state in the Niger Delta basin using GIS with a view to drawing attention to the remediation of the area. The study area lies between longitude 05° 38’ 36.47”E to 05°4’ 26.56” E and latitude 06° 4’ 28.17”N to 06° 4’ 33.79”N. 1km2 of the study area was georeferenced, digitized and gridded at 100 m interval using Google earth imagery. Soil samples were collected at the grid intersections, at depth ranging from 0-15 cm (topsoil), 15-30 cm (mid depth) and 30-60 cm (last depth). Soil samples were analyzed using Gas Chromatogram – Flame Ionization Detector (GC-FID) instrument. The result showed that Total Petroleum Hydrocarbon (TPH) concentration at the subsurface ranged from 96.88±3.74 to 870.01 ±102.43 mg/kg, mid depth concentration was between 46.92±7.13 to 404.03±7.10 mg/kg while the last depth is between 10.74±6.62 to 106.52±23.04 mg/kg. Due to severe pollution level at intersections C, Dand E; matlab curve fitting was used to predict the maximum depth at which hydrocarbon contaminant seized to exist in the soil; the results showed that at maximum vertical depth of 460m, TPH seizes to exist in the soil (below detection level)
PRICE FLUCTUATION AND SPATIAL MARKET INTEGRATION OF RICE IN ADAMAWA STATE RICE MARKET
Get PDFThis study investigates spatial price transmission for rice in Adamawa state, Nigeria. Data on weekly basis for the prices of 100kg was collected from ten markets for 52 weeks (September 2015 - August 2016). Data were analyzed with an econometric framework based on the estimation of Autoregressive Distributed lags models, and of the corresponding Error correction specification. Test for Granger causality was also performed. The extent of divergence of the lowest price from the highest price over the period of twelve months wasused to examine the dynamics of price behavior of rice marketing. The result of seasonal variation in price revealed that October and November is the period when rice prices are generally low while the highest price month occurred in December
IN VITRO ANTIOXIDANT ACTIVITY OF AQEOUS LEAF EXTRACT OF Delonix regia
Get PDFFree radicals are reactive particles engaged with numerous physiological processes and have been related with numerous illnesses. Therefore, there is need to investigate substances with free radical scavenging ability. The present investigation was intended to assess the free radical scavenging action of aqueous extract of leaf of Delonix regia utilizing different in vitro models. The extract was subjected to qualitative and quantitative (total phenol, total flavonoid and total antioxidant capacity) phytochemical screening. Ascorbic acid was the reference in the investigation. 1,1-Diphenyl-2-picryl hydroxyl (DPPH) and nitric oxide scavenging assays, as well as reducing power assay were carried out in this analysis. The capacity of the extracts to restrain lipidperoxidation was estimated by the in vitro lipid peroxidation assay. The extracts were at 20, 40, 60, 80 and 100 μg/mL concentrations and radical scavenging activity was determined in terms of inhibition percentage. The IC50 (concentration required for 50 % inhibition) was likewise ascertained for every radical. Qualitative phytochemical screening uncovered the presence of alkaloid, flavonoid, tannin, saponin, diterpenes, phenol, amino acids. The study additionally uncovered that the aqueous extract of Delonix regia leaf has a high radical scavenging action in the different radical systems. The total phenolic content and, flavonoid contents were 34.31 ± 0.169 mg Gallic acid equivalent (GAE)/g extract and 55.765±0.898 mg Quercetin/g extract respectively while the total antioxidant capacity was 52.33±1.443 mg ascorbic acid equivalent. The antioxidant activity of Delonix regia aqueous leaf extract could be related to high flavonoid and phenol content of the plant.