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Electrical geophysical evaluation of susceptibility to flooding in University of Nigeria, Nsukka main campus and its environs, Southeastern Nigeria
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作者 Daniel Nnaemeka Obiora Johnson Cletus Ibuot 《Journal of Groundwater Science and Engineering》 2023年第4期422-434,共13页
Flooding occurs when rainfall exceeds the absorption capacity of soil and causes significant environmental consequences.In this study,electrical resistivity techniques were employed to assess the flood susceptibility ... Flooding occurs when rainfall exceeds the absorption capacity of soil and causes significant environmental consequences.In this study,electrical resistivity techniques were employed to assess the flood susceptibility of the study area by examining variations in electrical properties.Prior to flooding,Vertical Electrical Sounding(VES)and Electrical Resistivity Tomography(ERT)profiles were conducted to determine the variations in resistivity within subsurface lithologies exposed to the injected current.The injected current penetrated the subsurface units characterised by resistivity ranging from 190.5Ω·m to 6,775.7Ω·m,42.3Ω·m to 7,297.4Ω·m,and 320.2Ω·m to 24,433.3Ω·m in the first,second and third layers,respectively.These layers were identified as lateritic topsoil,medium-coarse brownish grained sand,and coarse pebbly blackish sand,respectively.The calculated reflection coefficients between layers 1,2,and 3 reveal alternation in layers with values ranging from−0.04 to 0.66 and 0.36 to 0.95 for and,respectively.The transverse resistivity,longitudinal resistivity and anisotropy ranged from 243.59Ω·m to 24,115.42Ω·m,199.61Ω·m to 14,950.76Ω·m,and 1.02 to 2.14.Models derived from the ERT profiles reveal variations in resistivity,pinpointing areas of low resistivity which correspond to waterlogged and impermeable layers.The result of this study underscores the importance of integrated resistivity techniques in the study of floods,as it provides valuable insights into flood behaviour,and subsurface dynamics. 展开更多
关键词 Anisotropy Vertical electrical sounding Electrical resistivity tomography Geoelectric layer Permeability
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Evaluation of Hydrocarbon Potential Using AVO Analysis in the FORMAT Field, Niger Delta Basin, Nigeria
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作者 Charles Chibueze Ugbor Onyebuchi Samuel Onyeabor Ifeanyi Celestine Ugwuoke 《Open Journal of Geology》 CAS 2024年第3期403-430,共28页
The study involved the evaluation of the hydrocarbon potential of FORMAT Field, coastal swamp depobelt Niger delta, Nigeria to obtain a more efficient reservoir characterization and fluid properties identification. De... The study involved the evaluation of the hydrocarbon potential of FORMAT Field, coastal swamp depobelt Niger delta, Nigeria to obtain a more efficient reservoir characterization and fluid properties identification. Despite advances in seismic data interpretation using traditional 3D seismic data interpretation, obtaining adequate reservoir characteristics at the finest level had proved very challenging with often disappointing results. A method that integrates the amplitude variation with offfset (AVO) analysis is hereby proposed to better illuminate the reservoir. The Hampson Russell 10.3 was used to integrate and study the available seismic and well data. The reservoir of interest was delineated using the available suite of petrophysical data. This was marked by low gamma ray, high resistivity, and low acoustic impedance between a true subsea vertical depth (TVDss) range of 10,350 - 10,450 ft. The AVO fluid substitution yielded a decrease in the density values of pure gas (2.3 - 1.6 g/cc), pure oil (2.3 - 1.8 g/cc) while the Poisson pure brine increased (2.3 to 2.8 g/cc). Result from FORMAT 26 plots yielded a negative intercept and negative gradient at the top and a positive intercept and positive gradient at the Base which conforms to Class III AVO anomaly. FORMAT 30 plots yielded a negative intercept and positive gradient at the top and a positive intercept and negative gradient at the Base which conforms to class IV AVO anomaly. AVO attribute volume slices decreased in the Poisson ratio (0.96 to - 1.0) indicating that the reservoir contains hydrocarbon. The s-wave reflectivity and the product of the intercept and gradient further clarified that there was a Class 3 gas sand in the reservoir and the possibility of a Class 4 gas sand anomaly in that same reservoir. 展开更多
关键词 AVO Analysis Hydrocarbon Potential Fluid Properties Reservoir Characterization Petrophysical Data Hampson Russel
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Application of Predictive Model for Efficient Cassava (Manihot esculenta Crantz) Yield in the Face of Climate Variability in Enugu State, Nigeria
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作者 Emeka Bright Ogbuene Tonia Nkiru Nwobodo +7 位作者 Obianuju Gertrude Aloh Achoru Fred Emeka Josiah C. Ogbuka Vivian Amarachi Ozorme Andrew M. Oroke Obiageli Jacinta Okolo Anwara Obianuju Amara E. S. Enemuo 《American Journal of Climate Change》 2024年第2期361-389,共29页
Climate variability as occasioned by conditions such as extreme rainfall and temperature, rainfall cessation, and irregular temperatures has considerable impact on crop yield and food security. This study develops a p... Climate variability as occasioned by conditions such as extreme rainfall and temperature, rainfall cessation, and irregular temperatures has considerable impact on crop yield and food security. This study develops a predictive model for cassava yield (Manihot esculenta Crantz) amidst climate variability in rainfed zone of Enugu State, Nigeria. This study utilized data of climate variables and tonnage of cassava yield spanning from 1971 to 2012;as well as information from a questionnaire and focus group discussion from farmers across two seasons in 2023 respectively. Regression analysis was employed to develop the predictive model equation for seasonal climate variability and cassava yield. The rainfall and temperature anomalies, decadal change in trend of cassava yield and opinion of farmers on changes in rainfall season were also computed in the study. The result shows the following relationship between cassava and all the climatic variables: R2 = 0.939;P = 0.00514;Cassava and key climatic variables: R2 = 0.560;P = 0.007. The result implies that seasonal rainfall, temperature, relative humidity, sunshine hours and radiation parameters are key climatic variables in cassava production. This is supported by computed rainfall and temperature anomalies which range from −478.5 to 517.8 mm as well as −1.2˚C to 2.3˚C over the years. The questionnaire and focus group identified that farmers experienced at one time or another, late onset of rain, early onset of rain or rainfall cessation over the years. The farmers are not particularly sure of rainfall and temperature characteristics at any point in time. The implication of the result of this study is that rainfall and temperature parameters determine the farming season and quantity of productivity. Hence, there is urgent need to address the situation through effective and quality weather forecasting network which will help stem food insecurity in the study area and Nigeria at large. The study made recommendations such as a comprehensive early warning system on climate variability incidence which can be communicated to local farmers by agro-meteorological extension officers, research on crops that can grow with little or no rain, planning irrigation scheme, and improving tree planting culture in the study area. 展开更多
关键词 Climate VARIABILITY Cassava (Manihot esculenta Crantz) Predictive Model YIELD
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Geohydraulic Investigation of Aquifer Parameters in Abak, Southern Nigeria
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作者 Promise James Akpan Akaninyene Okon Akankpo +2 位作者 Joseph Gordian Atat Johnson Cletus Ibout Emmanuel Bassey Umoren 《Journal of Geoscience and Environment Protection》 2024年第5期289-301,共13页
A geophysical investigation was carried out to characterize aquifer parameters and assess the groundwater condition in Abak, southern Nigeria. Vertical electrical sounding (VES) was carried out using Schlumberger conf... A geophysical investigation was carried out to characterize aquifer parameters and assess the groundwater condition in Abak, southern Nigeria. Vertical electrical sounding (VES) was carried out using Schlumberger configuration in 10 locations within the area. Both manual and computer interpretation of the resistivity data reveals three to four geoelectric units (laterite topsoil, medium-grained sand, coarse-grained sand, and sandy clay sand) which agrees with the lithologic log from existing boreholes. The aquifer layer was identified along the third formation with resistivity values ranging from 1239 - 5719 Ωm and aquifer depth ranging from 30.2 - 54.8 m. The aquifer thickness ranged from 24.2 - 43.7 m. Hydraulic conductivity ranged from 0.1206 m/day - 0.5026 m/day with an average value of 0.29403 m/day. Formation factor ranged from 14.55 - 16.64. Porosity ranged from 15.98% - 22.40%, with an average value of 19.64%. The aquiferous zone falls within the medium/coarse-grained sand. The aquifer is shallow, unconfined, and prolific with a little overburden formation of 13.5 m. The area shows good prospects for groundwater development. 展开更多
关键词 Electrical Resistivity POROSITY Formation Factor Hydraulic Conductivity
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Performance Evaluation of the Lionet Quality of Service in Nsukka Campus of the University of Nigeria
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作者 Udora N. Nwawelu Anthony N. Nzeako +1 位作者 Mamilus A. Ahaneku Vincent C. Chijindu 《International Journal of Communications, Network and System Sciences》 2014年第4期122-129,共8页
Efficient performance of the Lionet in Nsukka campus of the University of Nigeria may be hindered by the ornamental trees that characterises the physical features of the University environment. This work measured and ... Efficient performance of the Lionet in Nsukka campus of the University of Nigeria may be hindered by the ornamental trees that characterises the physical features of the University environment. This work measured and analyzed the Lionet quality of service (QoS) in terms of received power level and path loss as functions of distance, under free space condition and in the presence of a tree. To achieve this, Ordinary Least Squares (OLS) regression analysis was used on the measured data with the help of SPSS version 16.0 software;to show the significance of the presence of trees on the Lionet QoS. The findings revealed that path loss is influenced significantly if 展开更多
关键词 Lionet QoS PATH Loss RECEIVED Power Level Access Point
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Spatial Disparity in Availability of Tuberculosis Diagnostic Services Based on Sector and Level of Care in Nigeria 被引量:1
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作者 Bethrand Odume Sani Useni +12 位作者 Egwuma Efo Degu Dare Elias Aniwada Nkiru Nwokoye Ogoamaka Chukwuogo Chidubem Ogbudebe Michael Sheshi Aminu Babayi Emperor Ubochioma Obioma Chijioke-Akaniro Chukwumah Anyaike Rupert Eneogu Debby Nongo 《Journal of Tuberculosis Research》 CAS 2023年第1期12-22,共11页
Background: Delay in Tuberculosis (TB) diagnosis can contribute to late presentation, severe disease, and continued transmission. KNCV TB Foundation Nigeria through the United States Agency for International Developme... Background: Delay in Tuberculosis (TB) diagnosis can contribute to late presentation, severe disease, and continued transmission. KNCV TB Foundation Nigeria through the United States Agency for International Development (USAID) funded the TB Local Organization Network (LON) 1 and 2 projects that explored the availability of Tuberculosis services based on sector and levels of care. Methods: TB Patient Pathway Analysis was carried out in 14 states comprising 92 facilities. It involved primary, secondary, and tertiary levels of health care in both the public and private sectors. This was a cross-sectional study under program implementation. Proforma was used to collect data on the available TB diagnostic services. Results: In public health facilities, GeneXpert was available at 100% in tertiary facilities in 8 (57%) states;up to 82% in 4 (33%) states, 50% available at secondary facilities in 2 states, and There is none at the primary facilities. Smear microscopy was available at 100% in tertiary facilities in 9 (64%) states and 3 (25%) states have 50% to 82%;secondary -10 (71%) states have > 70% at facilities;primary 1 (7%) state has it in 61% of facilities. Loop-mediated isothermal amplification (TB-LAMP) in tertiary 2 (17%) states have 20% and 100% respectively;secondary 4 (<30%) states have in 1 or 2 facilities;none for primary facilities. In private health facilities, 79% of states have Smear microscopy at both primary and secondary facilities, and only 2 states (14%) at tertiary facilities. Only 1 (7%) state has GeneXpert in all tertiary facilities, 2 (14%) states have secondary facilities, and 4 states in about 1% of facilities. TB LAMP was not available in any tertiary facility, one (7%) state at secondary with coverage of 1%, and 2 (14%) states at primary both with 4% overall facility coverage. Conclusions: There is an inequitable distribution of TB diagnostic services in both sectors and levels of care in Nigeria. TB care and control will improve with enhanced equitable distribution of TB diagnostic services across the health system. 展开更多
关键词 TUBERCULOSIS Diagnostic Services DISPARITY SECTOR LEVEL NIGERIA
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Evaluation of Hydrocarbon Reservoir in the “SIMA” Field of Niger Delta Nigeria from Interpretation of 3D Seismic and Petrophysical Log Data
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作者 Charles Chibueze Ugbor 《International Journal of Geosciences》 CAS 2023年第1期94-107,共14页
3D seismic and petrophysical log data interpretation of reservoir sands in “SIMA” Field, onshore Niger Delta has been undertaken in this study to ascertain the reservoir characteristics in terms of favourable struct... 3D seismic and petrophysical log data interpretation of reservoir sands in “SIMA” Field, onshore Niger Delta has been undertaken in this study to ascertain the reservoir characteristics in terms of favourable structural and petrophysical parameters suitable for hydrocarbon accumulation and entrapment in the field. Horizon and fault interpretation were carried out for subsurface structural delineation. In all, seven faults (five normal and two listric faults) were mapped in the seismic section. These faults were major structure building faults corresponding to the growth and antithetic faults in the area within the well control. The antithetic fault trending northwest-southeast and the normal fault trending northeast-southwest on the structural high in the section act as good trapping mechanisms for hydrocarbon accumulations in the reservoir. From the manual and auto-tracking methods applied, several horizons were identified and mapped. The section is characterized by high amplitude with moderate-to-good continuity reflections appearing parallel to sub-parallel, mostly disturbed by some truncations which are more fault related than lithologic heterogeneity. The southwestern part is, however, characterized by low-to-high or variable amplitude reflections with poor-to-low continuity. Normal faults linked to roll-over anticlines were identified. Some fault truncations were observed due to lithologic heterogeneity. The combination of these faults acts as good traps for hydrocarbon accumulations in the reservoir. Reservoir favourable petrophysical qualities, having average NTG, porosity, permeability and water saturation of 5 m, 0.20423, 1128.219 kD and 0.458 respectively. 展开更多
关键词 Seismic Interpretation Hydrocarbon Accumulation POROSITY RESERVOIR Niger Delta Petrophysical Properties FAULTS HORIZONS
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Hydrocarbon Prospectivity and Risk Assessment of “Bob” Field Central Swamp Depobelt, Onshore Niger Delta Basin, Nigeria
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作者 Charles Chibueze Ugbor Celestine Ifeanyi Ugwuoke Peter O. Odong 《Open Journal of Geology》 2023年第8期847-882,共36页
This paper evaluates the hydrocarbon prospectivity and play risks of “Bob” field in Niger Delta Basin, Nigeria. The aim is to enhance exploration success through improved approach/technique by incorporating risk ana... This paper evaluates the hydrocarbon prospectivity and play risks of “Bob” field in Niger Delta Basin, Nigeria. The aim is to enhance exploration success through improved approach/technique by incorporating risk analysis that previous studies have not fully considered. This approach combines a set of analyses including stratigraphic/structural, amplitude, petrophysical parameter, volumetric and play risk using a suite of well logs and 3D seismic data. Maximum amplitude anomaly map extracted on the surfaces of delineated 3 reservoirs revealed 6 prospects, namely: Dippers, Cranes, Turacos, Nicators, Jacanas and Pelicans with hydrocarbon accumulation. Petrophysical analysis showed ranges of values for porosity, permeability and water saturation of 0.21 to 0.23, 158.96 to 882.39 mD, and 0.07 to 0.11, respectively. The various prospects yielded the following stock tank volumes 12.73, 6.84, 3.84, 11.32, 7.42 and 4.76 Million barrels (Mbls) each respectively in a column of 66 ft reservoir sand in the study area. Play risk analysis results gave: Pelicans and Nicators (low), Turacos and Dippers (moderate), while Jacanas and Cranes show high risk with minimal promise for good oil accumulation. The prospects possess good reservoir petrophysical properties with low to moderate risk, thus, viable for commercial hydrocarbon production, which increases confidence in management decisions for production. 展开更多
关键词 Seismic Reservoir Hydrocarbon Prospectivity Risk Analysis VOLUMETRIC Niger Delta Basin
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In Search of Portable Water Supplies within a Brine and Mine Water-Invaded Region for Serving Some Communities around Ishiagu, Afikpo and Environs in Abakaliki Basin, Southeast Nigeria
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作者 Charles Chibueze Ugbor 《International Journal of Geosciences》 CAS 2023年第2期209-225,共17页
The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in th... The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl<sup>-</sup>, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, SO<sub>4</sub><sup>2-</sup>, HCO<sub>3</sub><sup>-</sup>) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone at depth. In addition, desalination could also potentially render the salt water drinkable if properly handled to eliminate the high concentration of salts in the water to the level of acceptable limit by the WHO. Based on the study, the best area to target for portable water in the study area is Afikpo, with most geochemical elements naturally occurring within WHO’s standard concentration while portable water could be harnessed in areas further away from mining sites, especially at deep groundwater. 展开更多
关键词 Abakaliki Basin Portable Water Brine Aquifer Salt Lake Pollution Desaline Water
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Estimation of Aquifer Transmissivity Using Dar Zarrouk Parameters at Ogbozara-Ekwegbe-Agu and the Environ, Enugu State, Nigeria
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作者 Charles Chibueze Ugbor Ugochukwu Kingsley Ogbodo 《Open Journal of Geology》 2023年第8期783-805,共23页
This study was undertaken to determine the hydrologic properties of the aquifer materials at Ogbozara-Opi/Ekwegbe-Agu and environs by the estimation of the aquifer transmissivity using Dar Zarrouk parameters. The stud... This study was undertaken to determine the hydrologic properties of the aquifer materials at Ogbozara-Opi/Ekwegbe-Agu and environs by the estimation of the aquifer transmissivity using Dar Zarrouk parameters. The study area lies in the Anambra basin and is underlain, from bottom to top, by 3 prominent geologic formations;Enugu Formation, Mamu Formation and Ajali Formation respectively. A total of 19 sounding stations were occupied within the study area using the Ohmega resistivity meter. The VES data were interpreted using the conventional partial curve matching technique to obtain initial model parameters which were later used as input data for computer iterative modelling using the Interpex software. These analyses were further combined with information from two existing boreholes in the study area to estimate aquifer hydraulic parameters using Dar-Zarrouk parameters. The layer parameters thus obtained revealed that the dominant curve type obtained from the different formations is the AK curve type followed by the HK curve type. An average of 6 geo-electric layers were delineated across all transect taken with resistivity values ranging from 25.42 - 105.85 Ωm, 186.38 - 3383.3 Ωm and 2992.3 - 6286.4 Ωm in the Enugu, Mamu and Ajali Formations respectively. Results of the study revealed the aquifer resistivity in the study area ranges from 1 - 500 Ωm. The depth to the water table range from 13 - 208 m with a mean value of 76.05, while aquifer thickness varies between 95 and 140 m with a mean value of 102.89 m. The values of the Dar-Zarrouk parameters revealed that the transverse resistance varies between −10,000 - 170,000 Ωm<sup>2</sup>, while the longitudinal conductance varies from 0.1 - 1 to 1.9 Ω - 1. Similarly, the hydraulic conductivity in the area ranges from 5 to 50 m/day, while the transmissivity values range from 1000 to 14,000 m<sup>2</sup>/day. 展开更多
关键词 AQUIFER Dar Zarrouk Parameters VES TRANSMISSIVITY CONDUCTANCE
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Analysis of Land Use Change and Associated Implications on Soil Ecosystem Functions in South Eastern Nigeria
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作者 Nwabueze I. Igu Chinero N. Ayogu +1 位作者 Chidimma C. Umeogu Michael C. Obikwelu 《Journal of Geoscience and Environment Protection》 2023年第5期126-134,共9页
Land use change affects soil functions and its capacity to provide ecosystem services. Though much of the tropics are experiencing accelerated increases in land use change, associated impacts of such changes are poorl... Land use change affects soil functions and its capacity to provide ecosystem services. Though much of the tropics are experiencing accelerated increases in land use change, associated impacts of such changes are poorly understood and studied. This study assessed the extent to which land use changes affect the soil ecosystem functions in a rainforest zone of south eastern Nigeria. Soil samples were collected from 24 sample locations in selected natural forest, cashew and palm plantations. Samples were analyzed in triplicate in the laboratory for geochemical analysis, after which the result was subjected to statistical analysis—ANOVA, correlation and regression. Forest carbon had higher % mean carbon content;though there was no significant difference (F (2, 21) = .246, p = .784) in carbon level across land uses. R value of .301 showed low correlation between % carbon, organic matter and % loss in ignition. Furthermore, R<sup>2</sup> value of 9.1% total variation in the dependent variable could only be explained by the independent variables. CEC, Nitrogen, Potassium and Phosphorus content of the land uses did not differ significantly: CEC (F (2, 21) = .844, p (.44);Nitrogen (.243), p (.79), Potassium (.140), p (.87), Phosphorus (.783), p (.47). This showed that there was no significant variation in soil fertility of the land uses, although natural forest had higher concentrations for these variables. Across the land uses, soil texture equally had no significant variations: % sand (F (2, 21) = .320, p (.729) % clay (.430), p (.656), % silt (.043), p (.958). Soil carbon was seen to be more enhanced in natural forest ecosystems than other land uses. Though plantations had reduced capacities to provide ecosystem functions, establishing such in modified landscapes is still advocated as they can coexist with such and yet ensure ecosystem functions. 展开更多
关键词 Climate Change Ecosystem Services Forest Loss Modification Soil Processes
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Evaluation of Some Selected Metals in Rice Cultivated in Four Local Government Areas in Enugu State, Nigeria
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作者 Christopher O. Alisa Samuel C. Nwobodo +4 位作者 Edith N. Alisa Peter C. Okeke Ali Bilar Jailen Doyle Lovell Agwaramgbo 《Journal of Geoscience and Environment Protection》 2023年第11期141-150,共10页
In this study, we investigated the presence of Zn, Fe, Cu, and Ca in rice cultivated in four local government areas (Nkanu East, Aninri, Uzo Uwani, Isi Uzo) within Enugu state, Nigeria. We employed an Atomic Absorptio... In this study, we investigated the presence of Zn, Fe, Cu, and Ca in rice cultivated in four local government areas (Nkanu East, Aninri, Uzo Uwani, Isi Uzo) within Enugu state, Nigeria. We employed an Atomic Absorption Spectrometer with an air acetylene flame to analyze these metals after digesting the rice samples. Risk assessment studies were carried out to determine any potential health risk to consumers by evaluating the estimated daily intake (EDI), the target hazard quotient (THQ) and hazard index (HI). The average concentration (mg/kg) of trace metals in the rice samples was within the acceptable limits established by FAO/WHO. Specifically, Zn ranged from 0.265 to 0.632 mg/kg, Fe from 2.73 to 4.131 mg/kg, Cu from 0.205 to 4.131 mg/kg, and Ca from 9.718 to 12.150 mg/kg. There were no statistically significant differences in metal concentrations among the various locations. Consequently, the rice analyzed in this study can be considered safe for consumption. The calculated EDI (mg/kg-day) values were below the maximum tolerable daily intake thresholds. THQ values also fell within safe levels, and the HI values were less than 1, signifying no potential health risks associated with consuming rice from these locations. In conclusion, there is no significant non-carcinogenic health risk associated with exposure to trace metals through the consumption of rice from these areas. 展开更多
关键词 Trace Metals RICE Risk Assessment Target Hazard Quotient Hazard Index ENUGU
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Biotechnology of Okpeye: A Nigerian Traditional Fermented Food Condiment
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作者 Uchenna K. Akpi Nurul Aqilah Mohd Zaini +3 位作者 Chukwudi Innocent Nnamchi Jerry Obetta Ugwuanyi Wan Abd Al Qadr Imad Wan-Mohtar Wan Syaidatul Aqma Wan Mohd Noor 《Advances in Microbiology》 2023年第8期373-385,共13页
Most legumes and oil bean seeds used in condiment manufacture in Africa are inedible by nature. They contain antinutritional elements such indigestible oligosaccharides and phytate. Fermentation affects desired altera... Most legumes and oil bean seeds used in condiment manufacture in Africa are inedible by nature. They contain antinutritional elements such indigestible oligosaccharides and phytate. Fermentation affects desired alterations by lowering anti-nutritional components and enhancing digestibility. Okpeye is a traditional West African seasoning prepared from Prosopis africana seed solid substrate fermentation. Many homes consider it as a family business because the preparation follows a passed-down habit from previous generations as an inexpensive source of plant protein. However, natural nature of the fermentation process raises concerns about the consistency, quality, and safety of the finished product. Because the seasoning is created on a small scale with less sophisticated equipment and manufacturing procedures, there are concerns about microbial safety. Thus, fermentation process and the range of microbial composition involved in Prosopis africana okpeye production were evaluated in this review. Potential spoilage agents, as well as biochemical and nutritional changes occurring during production of okpeye are gaining interest among researcher. This review highlights information that can help in developing starter cultures in a controlled fermentation process that ensures quality, longer shelf life, and microbiological safety. 展开更多
关键词 Okpeye Prosopis africana FERMENTATION Legumes CONDIMENT
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Assessment of the Spectral Decomposition Techniques in the Evaluation of Hydrocarbon Potential of “BOMS” Field, Coastal Swamp Niger Delta, Nigeria
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作者 Charles Chibueze Ugbor Onyebuchi Samuel Onyeabor 《International Journal of Geosciences》 2023年第7期655-676,共22页
This study employs the different approaches of the spectral decomposition techniques to evaluate the hydrocarbon potential of the reservoir and analyse to determine the most efficient spectral decomposition technique ... This study employs the different approaches of the spectral decomposition techniques to evaluate the hydrocarbon potential of the reservoir and analyse to determine the most efficient spectral decomposition technique with better resolution using the “BOMS” Field, coastal swamp depobelt Niger Delta, Nigeria. A good number of drilled wells have failed both in the Niger Delta Basin and other basins due to a poor understanding of the reservoir properties in advance of drilling and identifying the best approach will help to minimize this risk. Seismic and well logs data together with the Hampson Russel 10.3 software were used for the study. The target reservoirs were identified from the suite of well logs at the horizons with low gamma ray, high resistivity, and low acoustic impedance between TVD (ft) of 10,350 - 10,450 ft. The analysis of the amplitude spectrum of the seismic data revealed that the distortion of interest lies between 5 - 60 Hz. Seismic data were then spectrally decomposed into several frequencies such as low frequency (15 Hz), mid-frequency (31 Hz), and high frequency (46 Hz) where distortions were observed. Time- frequency slices of 15 Hz and 23 Hz provided clearer events (potential hydrocarbon sand) indicated by high amplitude envelope (2200 - 2400) and amplitude anomalies. While the amplitude dropped in the mid-frequency (31 Hz), the high amplitude envelope and the high energy completely disappeared in the high (46 Hz) time-frequency slice. A comparison of the Short- time Fourier transform and the Basic Pursuit algorithm revealed that the Basic Pursuit provided a better resolution of the reservoir characteristics than the former. The Red, Green and Blue (RGB) colour blending model indicated that the channel was consistent with the low-frequency section and amplitude anomaly. 展开更多
关键词 Amplitude Hydrocarbon Evaluation Spectral Analysis Reservoir Sand Basic Pursuit CONVOLUTION
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Integrated Geological and Geophysical Mapping for Groundwater Potential Studies at Ekwegbe-Agu and Environs, Enugu State, Nigeria
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作者 Charles Chibueze Ugbor Ugochukwu Kingsley Ogbodo Osita Kelechi Eze 《Open Journal of Geology》 CAS 2024年第4期513-547,共35页
The study integrates both the geological and geophysical mapping techniques for groundwater potential studies at Ekwegbe-Agu and the environs, Enugu state, Nigeria for optimal citing of borehole. Located in the Anambr... The study integrates both the geological and geophysical mapping techniques for groundwater potential studies at Ekwegbe-Agu and the environs, Enugu state, Nigeria for optimal citing of borehole. Located in the Anambra Basin between latitudes 6˚43'N and 6˚47'N and longitudes 7˚28'E and 7˚32'E, it is stratigraphycally underlain by, from bottom to top, the Enugu/Nkporo, Mamu and Ajali Formation respectively, a complex geology that make citing of productive borehole in the area problematic leading to borehole failure and dry holes due to inadequate sampling. The study adopted a field and analytic sampling approach, integrating field geological, electrical resistivity and self-potential methods. The software, SedLog v3.1, InterpexIx1Dv.3, and Surfer v10 were employed for the data integration and interpretation. The result of the geological field and borehole data shows 11 sedimentary facies consisting of sandstone, shales and heterolith of sandstone/shale, with the aquifer zone mostly prevalent in the more porous sand-dominated horizons. Mostly the AK and HK were the dominant curve types. An average of 6 geo-electric layers were delineated across all transects with resistivity values ranging from 25.42 - 105.85 Ωm, 186.38 - 3383.3 Ωm, and 2992 - 6286.4 Ωm in the Enugu, Mamu and Ajali Formations respectively. The resistivity of the main aquifer layer ranges from 1 to 500 Ωm. The aquifer thickness within the study area varies between 95 and 140 m. The western and northwestern part of the study area which is underlain mainly by the Ajali Formation showed the highest groundwater potential in the area and suitable for citing productive boreholes. 展开更多
关键词 SEISMIC Ekwegbe-Agu GROUNDWATER RESISTIVITY Field Mapping Borehole Logging
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Bioassay Procedure for the Diagnosis of Aflatoxicosis in a Pig Farm in Nsukka, South East Nigeria
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作者 S. V. O. Shoyinka K. F. Chah +3 位作者 C. P. Eze W. S. Ezema I. R. Onoja P. U. Umeakuana 《Open Journal of Veterinary Medicine》 2014年第7期129-133,共5页
The owner of an intensively reared pig farm in Nsukka, South-East Nigeria reported the deaths (within one week) of 90 piglets (2-3 months of age) out of 150 piglets on the farm. The piglets were being fed home-compoun... The owner of an intensively reared pig farm in Nsukka, South-East Nigeria reported the deaths (within one week) of 90 piglets (2-3 months of age) out of 150 piglets on the farm. The piglets were being fed home-compounded ration composed of spent grain (which appeared moldy) and other locally sourced materials. Clinical signs observed in affected piglets include sudden loss of appetite, diarrhea and distress grunting sound prior to death. Symptomatic treatment of the piglets which included the use of antibiotics (tetracycline, LA) did not appear to have ameliorated the condition. At necropsy carcasses were generally in fair to good body condition;with subcutaneous hemorrhages, mainly under the skin of head and neck regions. Lungs were congested and edematous, with froth along the tracheal and bronchial airways. The liver and spleen were moderately congested, while the mucosae of the gastrointestinal tract (which was free of ingesta) appeared mildly hyperaemic. No pathogenic bacterium was isolated from the heart blood and spleen. Histologic section of the liver showed centrilobular hepatocytes vacoulation and necrosis with hypertrophy of Kupffer cells that were in erythrophagocytosis. There was moderate fibrinous exudation into the interlobular septae. Spleen section showed severe erythrophagocytosis, but mild haemosiderosis. White pulp was either reactive or depopulated. Lungs were severely haemorrhagic with bronchitis and bronchiolitis. A tentative diagnosis of mycotoxicosis was made and the spent grain-compounded ration was fed to different groups of ducklings, with/without arginine and lysine supplementation. On the bases of clinical signs and mortality pattern;gross and histologic changes in the liver of the ducklings, a definitive diagnosis of aflatoxicosis was made. This paper emphasizes the experimental feeding of suspected feeds/feed ingredient to ducklings as a reliable diagnostic model for aflatoxicosis. 展开更多
关键词 PIGS SPENT Grain AFLATOXICOSIS Ducklings
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Proximate analyses,in vitro antioxidant activity and GC-MS analyses of fermented Pentaclethra macrophylla seeds
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作者 Ikechukwu Okoro Parker Joshua +8 位作者 Innocent Okagu Christian Amah Nnamani Ikenna Nene Chiaka-Onyemeze Emeka Anaduaka David Obasi Prince Okoroh Daniel Orieke Victor Ogugua 《Life Research》 2024年第3期2-8,共7页
The present study assessed the proximate composition,in vitro antioxidant activity and GC-MS analyses of fermented Pentaclethra macrophylla seeds extract(FPMSE).The in vitro antioxidant activity was assessed using 2,2... The present study assessed the proximate composition,in vitro antioxidant activity and GC-MS analyses of fermented Pentaclethra macrophylla seeds extract(FPMSE).The in vitro antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazl(DPPH)while Gas Chromatography-Mass Spectrophotometry(GC-MS)technique was used to identify the volatile compounds in FPMSE.FPMSE revealed a dose dependent percentage inhibition of the extract on DPPH assay.Proximate composition of FPMSE constitutes respectively;ash(0.33±0.12%),protein(2.19±0.08%),fats and oil(80.60±0.00%),carbohydrate(16.88±0.00%)while moisture and fibre were not detected.However,the pulverised sample constitute respectively;ash(1.27±0.58%),protein(10.51±0.60%),moisture(8.27±0.12%),fats and oil(32.33±0.12%),fibre(7.27±0.12%)and carbohydrate(40.35±0.00%).GC-MS analyses revealed fourteen(14)fatty acids including Octadecanoic acid(1.95%),Benzyloxymethylimine(43.89%),2-Allylpent-4-enoic acid benzyl ester(26.25%),Hexadecanoic acid,methyl ester(1.09%),Oleic Acid(0.25%),9,12-Octadecadienoic acid,methyl ester(Omega-6-fatty acid)(1.52%).The bioactive compounds identified in FPMSE could contribute to the pharmacological properties of P.macrophylla seeds and hence,could be of considerable interest for the development of new drugs. 展开更多
关键词 Pentaclethra macrophylla in vitro antioxidant GC-MS fatty acids
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Simultaneous Waveform Inverse Modelling for Litho-Fluid Prediction in an Old Marginal, “Agbbo”Field, Onshore Niger Delta, Nigeria
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作者 Charles Chibueze Ugbor Peter Ogobi Odong Chukwuemeka Austine Okonkwo 《Journal of Geoscience and Environment Protection》 2024年第5期40-59,共20页
Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with un... Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field. 展开更多
关键词 Simultaneous Waveform Inversion Lithofacies Fluid Type Rock Physics HYDROCARBON Acoustic Impedance Mu-Rho Reservoir
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Energy Crisis in Nigerian University System: Implications of Self Auto-generation for Human Capital Development
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作者 Stephen Chijioke Nwanya 《Journal of Energy and Power Engineering》 2014年第12期2017-2026,共10页
Energy requirements for tertiary educational purpose is burgeoning, a reflection of its criticality to human asset formation and to use self auto-generation by petrol or diesel generators as the energy supply source i... Energy requirements for tertiary educational purpose is burgeoning, a reflection of its criticality to human asset formation and to use self auto-generation by petrol or diesel generators as the energy supply source is an unsustainable practice. The situation is worrisome in view of the noise pollution and nuisance that constitutes to the learning environment. This paper, therefore, determines the quantity of self generated energy supply, its intensity, the associated CO2 emissions and their possible implications for human capital development. A survey of generating sets was conducted using the University of Nigeria Nsukka as a representative of Nigerian universities. A walk-through-approach was adopted in gathering data and two metrics-life cycle cost and cost of electricity from auto-generation were used to determine the economic implications of the self generation. The results show that self auto-generation contributed installed energy capacity of amount 19 MVA, 20 MVA, 34 MVA, 11 MVA and 22 MVA to run human capital development activities, respectively for academic sessions from July 2006 to November 2010. The study helps us understand that reforms in educational sector are not effective as long as energy insecurity is a dominant factor. 展开更多
关键词 Self-generation energy impact human asset university.
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Mortality rates from a Nigerian isolate of the <i>Infectious Bursa Disease Virus</i>and passive haemagglutination antibody titer that protects chicks against challenge with the virus isolate 被引量:3
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作者 Maduike C. O. Ezeibe John O. A. Okoye +4 位作者 Temitope M. Ogunniran Paul C. Animoke Ijeoma J. Mbuko Ijeoma A. Nwankwo Augustine A. Ngene 《Health》 2013年第9期1355-1359,共5页
To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different anti... To determine passive haemagglutination (PHA) antibody titer that would protect chicks against Nigerian isolates of the Infectious Bursa Disease Virus (IBDV), five groups of chicks aged 30 days which had different antibody titers were challenged with a Nigerian isolate of virulent IBDV. Mortality rates of the different groups were plotted against their respective mean PHA antibody titers. A group with zero antibody titer had a mortality rate of 75% while those with PHA antibody titers of 185.6, 243.2, 256 and 307.2 had mortality rates of 40%, zero, zero and zero respectively. Linear equation generated for a line of best fit of the graph of mortality rates of the chicks on their IBD antibody titers gave antibody titer (X) at which mortality (Y) would be zero as 300. A mortality of 75% and the high antibody level needed to protect chicks suggest that the isolate may be a hypervirulent strain. 展开更多
关键词 Protective Antibody Titer Hypervirulent INFECTIOUS BURSA Disease VIRUS Strain NIGERIAN ISOLATE
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