FACULTY OF SCIENCE

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    4DS OF CURRICULUM MODEL, SUSTAINABLE DEVELOPMENT GOALS, AND CURRICULUM ON EDUCATION FOR SUSTAINABLE DEVELOPMENT.
    (2016) OGUNFOLAKAN, B.A
    Most archaeological works in southwestern Nigeria are concentrated in Ile-Ife, Esie, Old Oyo and Owo. In these areas, the focus of archaeological studies had been on different works of art in bronze, terracotta, wood and stone. Studies on cultural themes related to the issues of conflict, war and displacement which have implications for landscape archaeology of the area are often relegated to the background. The main goal of this research was to highlight how conflict, war and displacement impacted on the settlement history of parts of Osun State, southwestern Nigeria. The study also appraised human interactions with the environment and the concomitant effects on emergent settlement configurations. Oral and written data were collected from Ile-Ife, Ikire, Ipetumodu, Ila-Orangun, and Ajaba to generate anthropological data. Investigations aimed at identifying and collecting surface artifacts involved reconnaissance and detailed surveys of the studied sites. Excavations were carried out on potsherd pavements at Ajaba and Asi and on a refuse mound at Ajaba. Artifacts from surface collections and excavations were classified according to types, decoration and functional attributes. Analysis of Mo, Cu, Pb, and Ni of sherd samples was done using inductively coupled plasma mass spectrometry. Ten thin sections were made from selected sherd samples for determination of pottery fabric and inclusions. Palynological analysis of soil samples collected from different depths of the excavated mound was carried out using a microscope with an attached camera. Decorative motifs such as single twisted cord impression were common to all sites. With exception of sherds from Ila-Orangun, those from other areas were related in terms of types, fabric and functional attributes. Some of the sherds bore striking resemblance to those documented for Old Oyo and Ile-Ife with regard to type, decoration and function. Stylistically, the potsherd pavements at Asi and Ajaba were similar to those documented for Ile-Ife. A C-14 date of AD 1263 was obtained from charcoal at a depth of 80cm from the Ajaba mound excavation. Maize cob decoration was absent which indicated that Ajaba site was occupied prior to 16th century when maize was introduced into West Africa. Pollen of forest species and ornamental plants of Asian origin, such as Lagerstroemia indica, Casuarina equisetifolia and Delonix regia was identified from the excavated mound. These were abundant at the lower levels of the excavated mound. However, pollen of ornamental plants disappeared completely at the upper levels while secondary forest species and artifacts increased in abundance which was indicative of increase in human population and subsequent impact on vegetation. There was evidence of increased peopling of the area from around AD 1263. Oral and written records suggested that conflicts and war caused displacement and re-occupation of most of the settlements. Conflict and war resulted in the abandonment and reoccupation of all the sites, resulting in the delineation of several historical phases of occupation. Human impact on the environment was noted from the 13th century.
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    Repositioning Nigerian university system: perspective of an insider. Selected speeches of Professor Emeritus Ayo Banjo in commemoration of his 80th birthday
    (Ibadan University Press Publishing House, University of Ibadan, Ibadan, Nigeria., 2014) Olayinka, A. I.
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    Groundwater abstraction: a model for saltwater intrusion of coastal fresh water
    (2017) Adebo, B.; Adetoyinbo, A.
    The knowledge of salinity level and intrusion of saltwater into freshwater aquifer is necessary for groundwater monitoring and prediction in the coastal areas. In this work, an advection-dispersion saltwater intrusion model is used to study and simulate saltwater intrusion in a typical coastal aquifer. The aquifer portion was divided into grid with elements and nodes. Map of the study area indicating well locations was overlain on the grid system such that these locations coincide with the nodes. Chlorides at these wells were considered as initial nodal salinities. Results showed a highest and lowest increase in simulated chloride of 37.89 mg/L and 0.8 mg/L respectively. It also revealed that the chloride concentration of most of the considered well may climb unacceptable level in the next few years, if the current abstraction rate continues unabated
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    Determination of temperature profile of the lithosphere between zero and 150 km penetration at Itagunmodi, Nigeria
    (AJOL, 2019-06) Adetoyinbo, A. A.; Bello, A. K.
    In this work the temperature profile for the lithosphere was determined using data from radiogenic heat source and heat from other sources from 0 to 150 km depth was determined using a suitable mathematical expression. The temperature at the base of the lithosphere was given between 1200°C to 1600°C. The Fourier’s law was applied and the results showed that the profile range from 27.0°C to 1483.3°C. These results compared favourably well with existing literature values.
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    Assessment of building failure within and around quarries
    (2019-07) Adetoyinbo, A. A.
    The substructures of various engineering structures that were erected on the earth are being were been supported by the soil. Hence, the nature of the soil supporting these structures becomes an important issue. Quarry blasting peak particle velocity (QBPPV) is not sufficient to ascertain the causes of foundation failure, therefore, the physical parameters governing the competency of the soil supporting engineering structures need to be determine. This work investigated the possible causes of foundation failure of buildings within the vicinity of quarries. The investigation was done by carrying out Vertical Electrical Sounding (VES) and Radial Vertical Electrical Sounding (RVES) using Campus omega terrameter. The results show that buildings found within this area have shallow foundation and their foundations founded on sandy clay which can still support foundation The values of the degree of fracturing was found not to exceed 1.53 in this region which was not the case with the previous radial vertical electrical soundings, 1.94 was calculated as the highest degree of fracturing for RVES 1 while 1.83 was calculated for RVES 2. In all the RVES, degree of fracturing ranges between 1.02 to 1.94.
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    A four-point electrical resistivity method for detecting wood decay and hollows in living trees
    (Springer, 2019-05) Soge, A. O.; Popoola, O. I.; Adetoyinbo, A. A.
    An accurate method of detecting wood decay and hollows or cavities in living trees is useful for risk assessment and maintenance of both forest and urban trees. This study presents the implementation of the four-point electrical resistivity method for the early detection of the presence, location and extent of wood decay and hollows in living acacia trees (Senna cilata L.). Electrical resistivity measurement of randomly selected living acacia trees and a freshly-cut acacia tree with decay and hollows were taken to obtain electrical resistivity profiles for sound, decayed and hollowed trees. A laboratory experiment was set up to replicate the resistivity profiles. Wood decay and hollows were replicated at different depths in the laboratory prototype using good electrical conductors and insulators respectively. Resistivity profiles for the sound, decayed and hollowed trees were obtained from the experimental and field results. The resistivity profiles were applied to detect decay and hollows of similar dimensions in living trees through resistivity curve matching. The electrical resistivity of the decayed acacia tree was markedly lowered by an average factor of 5 compared to that of the sound acacia tree. Likewise, the electrical resistivity of the hollowed acacia tree was noticeably greater than that of the sound acacia tree by an average factor of 4. Wood decay and hollows modelled into the laboratory prototype were detected with relatively lower and higher resistivity anomalies respectively. The method indicated that 80% of the randomly selected living trees were sound, healthy trees, whilst 20% had decay and hollow at the time of measurements. This method is suitable for early detection of decay and hollows in hardwood trees.
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    Detection of decay and hollows in living almond trees (terminalia catappa L. roxb.) using electrical resistivity method
    (Springer, 2018-10) Soge, A.; Popoola, O.; Adetoyinbo, A.
    A precise and cost-efficient diagnostic technique for detecting decay and other structural defects in living trees is indispensable for the risk assessment and conservation of urban and forest trees. A study was carried out to detect the location and extent of decay and hollows (or cavities) in almond trees (Terminalia catappa L. Roxb.) using the four-point electrical resistivity method. Electrical resistivity measurements (ERm) of randomly selected living almond trees were taken using an earth resistivity meter, four probes and a modified form of Schlumberger electrode configuration. The ERm were used to obtain resistivity profiles (RP) of the trees. The RP of freshly cut healthy, decayed and hollowed trees were also obtained. A laboratory experiment was set up to replicate the RP of healthy, decayed and hollowed trees. Wood decay and cavities in trees were detected through RP matching. In comparison to healthy trees, wood decay and cavities in tree stems were detected with relatively sharp decrease and increase in electrical resistivity values, respectively. The extent of the resistivity anomalies corresponds to the extent of wood decay and cavities in trees. This method is applicable to early detection of decay and cavities in hardwood trees.
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    Gravity anomaly and basis symmetric matrix Interpretation for residuals
    (2018) Adetoyinbo, A. A.; Ewumi, T. O.
    Gravity method has tremendously pervaded the field of geophysical exploration and thus extensively discussed and vividly illustrated in this work. The basis for symmetric matrix data gravity interpretation was earlier proposed, then extended to residuals and interpretation. A symmetric matrix representation is discussed further to residuals, spectral, interpretation, and optimistically forms a veritable tool for gravity data interpretation. The fundamental law of gravitational attraction is essential in delineating gravity data interpretation and the gravity effect or anomaly representation is evidently expressed by a finite difference matrix in the discussion. A computational extension can be done based on the symmetric matrix representation with available gravity data and a vivid illustration for anomaly and residual computation has been made
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    Peak particlevelocitydataacquisitionfor monitoring blast induced earth quakes in quarry sites
    (Elsevier Inc., 2018) Hammed, O. S.; Popoola, O. I.; Adetoyinbo, A. A.; Awoyemi, M. O.; Adagunodo, T. A.; Olubosede, O.; Bello, A. K.
    The peak particle velocity datasets recorded during quarry blasts in the neighborhood villages and towns in Ibadan and Abeokuta were processed and analyzed in order to recommend a safe blast design for each of the quarries. The minimum peak particle velo- city of 48.27 mm/s was recorded near the foundation of the nearest residence at the shot to monitored distance of 500m. The ten- dency of ground vibration emanating from the quarry sites to cause damage to the structures in the nearby dwelling areas is very high. The peak particle velocity datasets recorded were not within the safe limit. Therefore, the peak particle velocity that will not exceed 35 mm/s is recommended for a safe blast design
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    Employing DC resistivity method for hydrogeological analysis of Zuma II, a VES approach
    (2017) Dikedi, P. N.; Sule, A. U.; Adetoyinbo, A. A.
    This research work employs the DC Resistivity method for Hydrogeological analysis in Veritas University, Zuma II, Bwari Area Council, Abuja, FCT, Nigeria. The work attempts to tackle the immense water shortage crisis within the University, this work also, attempts to provide access to stratigraphic information and to assist groundwater development for the region. Schlumberger array and electrical sounding technique are adopted for subsurface delineation. Eleven resistivity profile graphs generated from tabled data are presented by employing the Winresist software and Microsoft excel. A The outcome of this investigation revealed four spots with good potentials for ground water; these points are located within the fifth and third layers on 9.28498°N, 7.41875°E (VES 1); 9.28515°N, 7.41789°E (VES 5); 9.28437°N, 7.41793°E (VES 8); 9.28394°N, 7.41792°E (VES10). Furthermore, the outcome of this work revealed the lithology of the region investigated. Five distinct layers of varying thicknesses and depths were displayed: Top soil, Clay, Sandy clay, Fractured and Basement Rocks. From the collated readings, the derived average thicknesses of topsoil, sandy clay and clay are 0.8 m, 10.2 m and 7.06 m respectively.