Browsing by Author "Omeje M"
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Item Assessment of background radionuclides and gamma dose rate distribution in Urban-setting and its radiological significance(2020) Joel ES; De DK; Omeje M; Adewoyin O; Olawole OC; Akinwumi A; Erubami S; Adeyemi GABackground Awareness of the dangers associated with exposure to high radiation in the environment is necessary to avoid its health impact, especially when staying in-door. Method Assessment of gamma dose rate and radionuclides in urban settings of Ota has been carried out using a hand-held gamma detector to determine the hotspot of high radionuclides concentration in the study area. In this study, eighteen (18) stations were covered, gamma dose rate and radio-nuclides (Uranium-238, Thorium-232, and Potassium-40) emitting from the subsurface were measured. Results The result showed that the mean value for the measured dose rate of 45.06 nGh−1 is below the suggested value of 84 nGh−1 while the estimated mean values for the radionuclides are were 23.81, 45.35 and 77.82 Bq/kg respectively. The evaluated radium equivalent (Raeq), internal index (Hin), external index (Hex) and gamma index (Iy) ranges from 70.92 to 128.70 Bq/kg, 0.24 to 0.41, 0.19 to 0.35 and 0.25 to 0.46 respectively. Furthermore, the estimated value of the alpha index ranged between 0.05 and 0.15, and an annual effective dose rate from 0.33 to 0.55. The estimated mean value of excess cancer lifetime risk is 0.0015. Conclusions Therefore, the study suggests that the study area is safe for the residents. However, radioactivity concentration emanating from the subsurface of the setting should be monitored to avoid the environmental-health implication of accumulation of low gamma-dose, which can cause cancer of the lung due to anthropogenic activities.Item Comparison between experimental and satellite temperature datasets in Covenant University(2018) Akinwumi SA; Omotosho TV; Usikalu MR; Odetunmibi OA; Ometan OO; Adewusi MO; Omeje M; Joel ESThis article contains the ground and satellite meteorological data sets of clear-sky temperature events for five years (2012–2016) in Covenant University, Ota, Ogun State, Nigeria. The satellite data were obtained from Atmospheric Infrared Sounder (AIRS) while the ground data information were acquired from Davis weather station data logger-vantage pro2. These data were acquired from propagation study that used same location (Lat: 6.67°N and Long: 3.23°E) for both satellite data and radiometer directed along the same path by providing information about the temperature. The data sets were assessed and evaluated by means of a descriptive statistics. There was perfect agreement between the two data. The peak temperature events occurs between the months of November and April for the five years of observation for both Ota and AIRS Satellite. The data from this article can be used for further studies on non-rainy attenuation effect in the study area.Item Geo-investigation on groundwater control in some parts of Ogun state using data from Shuttle Radar Topography Mission and vertical electrical soundings(2020) Joel ES; Olasehinde PI; Adagunodo TA; Omeje M; Oha I; Akinyemi ML; Olawole OCGroundwater is a vital natural resource that plays a significant function in sustainability of living things on earth. Its exploration requires special skill for optimum exploitation. Shuttle Radar Topography Mission (SRTM)and Vertical Electrical Sounding (VES) were used to detectthe stratigraphy and subsurface structures controlling the groundwater system around Iju – Ota, Ogun State, Southwestern Nigeria. Nineteen (19) VES points were carried out where there were dense concentrations of lineaments and interconnected to establish the connection of the observed lineaments with groundwater occurrence in the study area using Schlumberger array, with electrode spacing of AB/2 varying from 180 to 320 m. The analysis of SRTM data revealedthe dominating structural NE-SW and NW-SE trends, which control aquifer structure. The geoelectrical parameters from the VES results were used to map the stratigraphic sequences in the study area. Six (6) units that comprisethe topsoil, lateritic clay, clayey sand, mudstone, sand (main aquifer), and shale or clay were identified in the study area. The aquiferous unit around Iju – Ota axis ranged from 30 to 80 m. Theextracted from the hill shaded SRTM data and the result of VES revealed that the thickness of the aquifer is as a result of interconnectivity of the lineaments observed in the SRTM data suggesting that the groundwater occurrence in the study area is chiefly controlled by these fractures.Item Radionuclides proportion and radiological risk assessment of soil samples collected in Covenant University, Ota, Ogun State Nigeria(2018) Adewoyin OO; Omeje M; Joel ES; Akinwumi SA; Ehi-Eromoseled CO; Embong ZThe activity levels of 238U, 232Th and 40K in soil surrounding major office complexes in Covenant University were analyzed for radiological hazards to determine the safety of the residents in such environment. Sixteen (16) soil samples were collected, prepared and sent to Acme laboratory in Canada for analysis with the use of high purity germanium detector. The mean activity concentrations of 238U, 232Th and 40K were found to be 45?±?10, 135?±?8 and 195?±?20 respectively. The concentrations of 238U and 232Th were found to be higher than the world recommended standard of 35 and 30, while the result for 40K was noted to be lower than the world safe limit. The average values of Raeq, D, AED, Iyr, Hex and ELCR in this study were estimated to be 252.33?Bq/kg, 110.15 nGy/h, 0.13 mSv/y, 1.78, 0.68 and 0.47?×?10-3 respectively. It was noticed that none of the measured parameters was higher than the internationally recommended safe limits. 232Th was found to be the major contributor to the environmental radionuclides in the area of study. Therefore, the inhabitants of the office complexes whose environment was assessed are considered not be exposed to any radiological hazards.