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Abiola O.K.,Federal University of Petroleum Resources | Tobun Y.,University of Lagos
Chinese Chemical Letters | Year: 2010

The ability of Cocos nucifera L. water (CW) as non-toxic corrosion inhibitor for acid corrosion of aluminium in 0.5 mol/L HCl has been studied using chemical technique. CW shows significant inhibition as corrosion inhibitor, with 93% efficiency at the highest concentration of the inhibitor. The inhibitive action is attributed to the adsorption of the inhibitor molecules on metal surface following Langmuir adsorption isotherm. © 2010 Olusegun K. Abiola.


Chukwude A.E.,University of Nigeria | Chukwude A.E.,Federal University of Petroleum Resources | Urama J.O.,University of Nigeria
Monthly Notices of the Royal Astronomical Society | Year: 2010

A detailed observation of the microglitch phenomenon in relatively slow radio pulsars is presented. Our analyses for these small amplitude jumps in pulse rotation frequency (ν) and/or spin-down rate () combine the traditional manual detection method (which hinges on careful visual inspections of the residuals of pulse phase residuals) and a new, and perhaps more objective, automated search technique (which exploits the power of the computer, rather than the eyes, for resolving discrete events in pulsar spin parameters). The results of the analyses of a sample of 26 radio pulsars reveal that (i) only 20 pulsars exhibit significant fluctuations in their arrival times to be considered suitable for meaningful microglitch analyses; (ii) a phenomenal 299 microglitch events were identified in ν and/or .: 266 of these events were found to be simultaneously significant in ν and , while 19 and 14 were noticeable only in ν and , respectively; (iii) irrespective of sign, the microglitches have fractional sizes which cover about three orders of magnitude in ν and and ) with median values as 0.78 × 10-9 and 0.36 × 10-3, respectively. © 2010 The Authors. Journal compilation © 2010 RAS.


Ojugo A.A.,Federal University of Petroleum Resources
Proceedings - 2015 2nd International Conference on Mathematics and Computers in Sciences and in Industry, MCSI 2015 | Year: 2015

Diabetes Mellitus (silent killer or sugar disease) is a metabolic disease characterized by high glucose levels, either in a body with insufficient insulin to breakdown glucose, or body that is resistant to effects of insulin. To improve early diagnosis, data-mining tools are used to help physicians effectively classify the disease. Study presents a hybrid fuzzy, genetic algorithm trained neural network model as a decision support system for diabetes classification. Adopted data is split into: training, cross validation and testing to aid model validation with appropriate weights and biases set for each variables. Results indicate that age, obesity and family relations (in first and second degree), environmental conditions are critical factors to be watched, While in gestational diabetes, mothers with or without a previous case of GDM is confirmed if there is: (a) history of babies with weight > 4.5kg at birth, (b) resistant to insulin showing polycystic ovary syndrome, and (c) have abnormal tolerance to insulin. © 2015 IEEE.


Asibor G.I.,Federal University of Petroleum Resources
Journal of Sustainable Development | Year: 2015

The benthic macro-invertebrate fauna of Asejire Reservoir, Southwest Nigeria were investigated for two years (2004-2006) covering both the rainy and dry seasons. The major objective of the study was to provide baseline information on aspects of the biology (taxonomic composition, occurrence, distribution and abundance) of the benthic macro-invertebrates, characteristics of the reservoir sediment. A total of twenty sampling stations were established to represent the various sections and regime of the lake. Sediment samples were collected from each station at bimonthly intervals using an improvised Van-veen grab. Altogether a total of three hundred and twenty composite samples were collected and analysed and assessed. The benthic macro-invertebrates comprised twenty-eight species in the class Insecta (13 taxa), Gastropoda (9 taxa), Bivalvia (2 taxa) while Arachnida, Malacostraca, Hirudinea and Gordiadea were made of one species each. Altogether a total abundance of 364,351 individual macro-invertebratess species were collected from the bottom sediment. The dominant species were Potadomamoerch, P. freethi and Melanoidestubaculata with a population of 119,985, 66,660 and 32,768 individual taxawhile the least occurring taxa were Sphaeriumsp and Hydracarinasp with a population of 550 and 1,350 individual. Considerable close association (p < 0.05) were found among many of the macro-invertebrates species. Species abundance was higher in the dry season (46 ±6.5 organism m-2) than in the rainy season (36 ± 6.0 organism m-2) but the difference between the two seasons was not significant (p > 0.05). More species were found in the littoral than in the open water region of the reservoir and the difference between the two regions was significant (p < 0.05). The differences in the abundance of species in the three reaches were also significant (p < 0.05). In conclusion, on the basis of benthic macro-invertebrate taxa composition and abundance, Asejire Reservoir can be inferred to be rich in fauna composition and therefore fairly clean and unpolluted. © by the authors.


Okedoye A.M.,Federal University of Petroleum Resources
Journal of Naval Architecture and Marine Engineering | Year: 2014

This paper study unsteady MHD mixed convection flow past an infinite vertical oscillating plate through porous medium, taking account of the presence of free/forced convection and mass transfer. Using similarity transformation, the coupled non – linear governing equations are solved numerically by applying the combination of the base scheme sub-methods – midpoint, and a method enhancement scheme Richardson extrapolation technique together with Fehlberg fourth-fifth order Runge-Kutta shooting iteration method with degree four interpolant. The results are obtained for velocity, temperature, concentration. The effects of various material parameters are discussed on flow variables and presented by graphs. © 2014 ANAME Publication. All rights reserved.


Agbalagba E.O.,Federal University of Petroleum Resources | Onoja R.A.,Ahmadu Bello University
Journal of Environmental Radioactivity | Year: 2011

This paper presents the findings of a baseline study undertaken to evaluate the natural radioactivity levels in soil, sediment and water samples in four flood plain lakes of the Niger Delta using a hyper pure germanium (HPGe) detector. The activity profile of radionuclides shows low activity across the study area. The mean activity level of the natural radionuclides 226Ra, 232Th and 40K is 20 ± 3, 20 ± 3 and 180 ± 50 Bq kg-1, respectively. These values are well within values reported elsewhere in the country and in other countries with similar environments. The study also examined some radiation hazard indices. The mean values obtained are, 76 ± 14 Bq kg-1, 30 ± 5.5 ηGy h-1, 37 ± 6.8 μSv y-1, 0.17 and 0.23 for Radium Equivalent Activity (Raeq), Absorbed Dose Rates (D), Annual Effective Dose Rates (Eff Dose), External Hazard Index (Hex) and Internal Hazard Index (Hin) respectively. All the health hazard indices are well below their recommended limits. The soil and sediments from the study area provide no excessive exposures for inhabitants and can be used as construction materials without posing any significant radiological threat to the population. The water is radiologically safe for domestic and industrial use. The paper recommends further studies to estimate internal and external doses from other suspected radiological sources to the population of the Biseni kingdom. © 2011.


Agbalagba E.O.,Federal University of Petroleum Resources | Avwiri G.O.,University of Port Harcourt | Ononugbo C.P.,University of Port Harcourt
Environmental Earth Sciences | Year: 2013

Oil mineral leases (30, 58 and 61) in Delta and River States are the major oil blocks in the oil and gas rich Niger Delta region of Nigeria that is characterized by environmental degradation from oil and gas activities. This research work presents an analytical approach on natural radioactivity assessment in soil and sediment in 15 oil fields of these OMLs. Concentrations of natural radionuclides (226Ra, 232Th and 40K) were determined using gamma spectroscopy. The mean activity concentration of 226Ra, 232Th and 40K for OML30 is 40.2 ± 5.1, 29.9 ± 4.2 and 361.5 ± 20.0 Bq kg-1, respectively; the corresponding values obtained for OML58 is 20.9 ± 2.8, 19.4 ± 2.5 and 260.0 ± 14.1 Bq kg-1, respectively. While the mean activity concentration of 226Ra, 232Th and 40K for OML61 is 29.3 ± 3.5, 21.6 ± 2.6 and 262.1 ± 14.6 Bq kg-1, respectively. These values obtained show enhanced NORMs, but are well within the world range and values reported in some regions and countries of the world, and are slightly above control values, values obtained in Southwestern region of Nigeria and some countries reported average values. The study also examined some radiation hazard indices, the mean values obtained are 86.6 ± 9.3 Bq kg-1, 0.6 Bq kg-1, 40.8 ηGy h-1, 0.05 μSv y-1, 0.2 and 0.3 for radium equivalent activity (Raeq), representative level index (Iγ), absorbed dose rates (D), annual effective dose rates (E ff dose), external hazard index (H ex) and internal hazard index (H in), respectively. These calculated hazard indices to estimate the potential radiological health risk in soil and sediment are well below their permissible limits. The soil and sediments from the study area provide no excessive exposures for the inhabitants and can be used as construction materials without posing any radiological threat or harm to the public users. However, oil-field workers and host community residents are cautioned against excess exposure to avoid future accumulative dose of these radiations from sludge and sediment of this area. © 2013 Springer-Verlag Berlin Heidelberg.


Gregory A.O.,University of Port Harcourt | Agbalagba E.O.,Federal University of Petroleum Resources
Environmental Earth Sciences | Year: 2014

Concentration of natural radionuclides in three major staple food crops cultivated around a fertilizer plant in Onne, Rivers State Nigeria and the cultivated soil samples were determined using gamma spectroscopy operated on a Canberra vertical high purity 3″ × 3″ NaI(TI) detector. The average activity concentration of 238U, 232Th and 40K was determined, for cassava flour (U 19.3 ± 5.0, Th 11.4 ± 3.3, K 426.9 ± 33.8) Bq kg-1, for yam flour (U 6.3 ± 1.8, Th 8.4 ± 2.6, K 227.0.9 ± 27.3) Bq kg-1 while for cocoyam flour (U 7.5 ± 2.7, Th 7.1 ± 2.3, K 195.8 ± 25.83) Bq kg-1. The mean activity concentration for soil samples is 18.7 ± 3.7 Bq kg-1, 18.0 ± 3.8 Bq kg-1 and 308.4 ± 22.4 Bq kg-1 for 238U, 232Th and 40K, respectively. These values obtained show enhanced 40K concentration which is attributed to the effluent discharge from a fertilizer plant and its applications to farmlands, but 238U, 232Th values are well within the global average and values reported in some regions and countries of the world. Radiation hazard indices obtained to estimate potential radiological health risk in both foodstuffs and soil samples are well below their permissible limit as set by UNSCEAR [Sources and effects of ionizing radiation (Report to the General Assembly), 2000]. The rate of radionuclides transfer from soil to crops was moderate with mean transfer factors of 232Th < 238U < 40K. © 2013 Springer-Verlag Berlin Heidelberg.


Agbalagba E.O.,Federal University of Petroleum Resources | Avwiri G.O.,University of Port Harcourt | Chad-Umoreh Y.E.,University of Port Harcourt
Journal of Environmental Radioactivity | Year: 2012

The analysis of naturally occurring radionuclides ( 226Ra, 232Th and 40K) has been carried out in soil samples collected from oil and gas field environment of Delta state, using gamma spectroscopy operated on a Canberra vertical high purity 2'×2' NaI(TI) detector. The activity concentration of the samples ranges from 19.2 ± 5.6Bqkg -1 to 94.2 ± 7.7Bqkg -1 with mean value of 41.0 ± 5.0Bqkg -1 for 226Ra, 17.1 ± 3.0Bqkg -1 to 47.5 ± 5.3Bqkg -1 with mean value of 29.7 ± 4Bqkg -1 for 232Th and 107.0 ± 10.2Bqkg -1 to 712.4 ± 38.9Bqkg -1 with a mean value of 412.5 ± 20.0Bqkg -1 for 40K. These values obtained are well within the world range and values reported elsewhere in other countries, but are little above some countries reported average values and some part of Nigeria. The study also examined some radiation hazard indices, the mean values obtained are, 98.5 ± 12.3Bq.kg -1, 0.8Bqkg -1, 54.6ηGyh -1, 0.07μSvy -1, 0.3 and 0.4 for Radium equivalent activity (Ra eq), Representative level index (Iγ), Absorbed Dose rates (D), Annual Effective Dose Rates (E ff Dose), External Hazard Index (H ex) and Internal Hazard Index (H in) respectively. These calculated hazard indices to estimate the potential radiological health risk in soil and the dose rate associated with it are well below their permissible limit. The soil and sediments from the study area provide no excessive exposures for inhabitants and can be use as construction materials without posing any immediate radiological threat to the public. However, oil workers in the fields and host communities are cautioned against excess exposure to avoid future accumulative dose of these radiations from sludge and sediment of this area. © 2011 Elsevier Ltd.


Abiola O.K.,Federal University of Petroleum Resources | James A.O.,University of Port Harcourt
Corrosion Science | Year: 2010

The effect of the extract of Aloe vera leaves on the corrosion of zinc in 2 M HCl solution was studied using weight loss technique. A. vera extract inhibited the corrosion of zinc in 2 M HCl solution and the inhibition efficiency increased with increasing concentration of the extract but decreased with increasing temperature. The adsorption of the inhibitor molecules on zinc surface was in accordance with Langmuir adsorption isotherm. A first-order kinetics relationship with respect to zinc was obtained with and without the extract from the kinetics treatment of the data. © 2009 Elsevier Ltd. All rights reserved.

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