Ladoke Akintola University of Technology

About: Ladoke Akintola University of Technology is a education organization based out in Ogbomoso, Nigeria. It is known for research contribution in the topics: Population & Adsorption. The organization has 2786 authors who have published 3066 publications receiving 36850 citations. The organization is also known as: Oyo State University of Technology & LAUTECH.

Groundwater Exploration in Aaba Residential Area of Akure, Nigeria

Abstract: Groundwater plays a fundamental role in human life. Despite its indispensable characteristics, it is unfortunate that groundwater is often associated with low yield. The expanding demand for water and the cost involved in drilling boreholes therefore require the application and the proper use of groundwater investigation techniques to locate high yielding aquifers. A geophysical investigation involving an electrical resistivity method using a Schlumberger electrode array was conducted around Aaba residential area, a basement terrain of southwestern Nigeria. Sixteen Vertical Electrical Sounding (VES) stations were applied across the study area using a maximum current electrode separation of 100 m. The geoelectrical imaging from this study revealed that the lithologies are divided into topsoil, lateritic soil, Sandy clay/ clayey sand/ clay/ weathered rock and the bedrock. Subsurface geoelectrical maps (overburden thickness, weathered layer isothickness, weathered layer isoresistivity, bedrock relief, bedrock resistivity and correlations from geoelectric sections) were used to generate information about the groundwater potential of the study area. It was inferred that the eastern (VESs 1, 2, 8, 10 and 11) and the southwestern (VESs 13 and 14) regions are associated with high groundwater yield. Boreholes can be drilled to an average depth of 22.0 m (72.6 ft) on these axes. The groundwater potential of the northern (VES 5), central (VES 9), and southern (VES 12) parts of the study area were inferred to be of medium potential. The borehole drilling along these axes can be extended to the depth of 30.0 m (99.0 ft), with medium groundwater yield. However, the northeastern (VES 3 and VES 4) and the western (VESs 6, 7, 15, and 16) zones are characterized by low groundwater potential. This present study has been able to detect the drillable zones and depths for optimum groundwater yield in a crystalline terrain of Aaba residential area, Akure using VES. The resistivity sounding is efficient in characterization of aquifers for groundwater exploration.

Improving the Demulsification Process of Heavy Crude Oil Emulsion through Blending with Diluent

Abstract: In crude oil production from brown fields or heavy oil, there is production of water in oil emulsions which can either be controlled or avoided. This emulsion resulted in an increase in viscosity which can seriously affect the production of oil from sand phase up to flow line. Failure to separate the oil and water mixture efficiently and effectively could result in problems such as overloading of surface separation equipments, increased cost of pumping wet crude, and corrosion problems. Light hydrocarbon diluent was added in varied proportions to three emulsion samples collected from three different oil fields in Niger delta, Nigeria, to enhance the demulsification of crude oil emulsion. The viscosity, total petroleum hydrocarbon, and quality of water were evaluated. The viscosity of the three emulsions considered reduced by 38, 31, and 18%. It is deduced that the increase in diluent blended with emulsion leads to a corresponding decrease in the value of viscosity. This in turn enhanced the rate of demulsification of the samples. The basic sediment and water (BS&W) of the top dry oil reduces the trace value the three samples evaluated, and with optimum value of diluent, TPH values show that the water droplets are safe for disposal and for other field uses.

Optimization and batch studies on adsorption of malachite green dye using rambutan seed activated carbon

Abstract: Rambutan seeds (Nephelium lappaceum L.)-based activated carbon (RSAC) was prepared using potassium hydroxide (KOH) activation and carbon dioxide (CO2) gasification methods. The adsorbent prepared was characterized using Fourier transform infrared, SEM, proximate analysis, and BET techniques, respectively. The effects of three variable parameters; activation temperature, activation time, and chemical impregnation ratio (IR) (KOH: char by weight) on the preparation of RSAC used for the removal of MG dye was investigated. Based on the central composite design, quadratic and two factor interaction (2FI) models were, respectively, employed to correlate the effect of variable parameters on the preparation of RSAC used for the percentage MG dye removal and activated carbon yield. From the analysis of variance, the most influential factor on each experimental design response was identified. The optimum conditions of MG dye removal by RSAC are: activation temperature (802°C), activation time (1.0 h), and I...

Arsenic-induced dyslipidemia in male albino rats: comparison between trivalent and pentavalent inorganic arsenic in drinking water

Abstract: Recent epidemiological evidences indicate close association between inorganic arsenic exposure via drinking water and cardiovascular diseases. However, the exact mechanism of this arsenic-mediated increase in cardiovascular risk factors remains enigmatic. In order to investigate the effects of inorganic arsenic exposure on lipid metabolism, male albino rats were exposed to 50, 100 and 150 ppm arsenic as sodium arsenite and 100, 150 and 200 ppm arsenic as sodium arsenate respectively in their drinking water for 12 weeks. Dyslipidemia induced by the two arsenicals exhibited different patterns. Hypocholesterolemia characterised the effect of arsenite at all the doses, but arsenate induced hypercholesterolemia at the 150 ppm As dose. Hypertriglyceridemia was the hallmark of arsenate effect whereas plasma free fatty acids (FFAs) was increased by the two arsenicals. Reverse cholesterol transport was inhibited by the two arsenicals as evidenced by decreased HDL cholesterol concentrations whereas hepatic cholesterol was increased by arsenite (100 ppm As), but decreased by arsenite (150 ppm As) and arsenate (100 ppm As) respectively. Brain cholesterol and triglyceride were decreased by the two arsenicals; arsenate decreased the renal content of cholesterol, but increased renal content of triglyceride. Arsenite, on the other hand, increased the renal contents of the two lipids. The two arsenicals induced phospholipidosis in the spleen. Arsenite (150 ppm As) and arsenate (100 ppm As) inhibited hepatic HMG CoA reductase. At other doses of the two arsenicals, hepatic activity of the enzyme was up-regulated. The two arsenicals however up-regulated the activity of the brain enzyme. We observed positive associations between tissue arsenic levels and plasma FFA and negative associations between tissue arsenic levels and HDL cholesterol. Our findings indicate that even though sub-chronic exposure to arsenite and arsenate through drinking water produced different patterns of dyslipidemia, our study identified two common denominators of dyslipidemia namely: inhibition of reverse cholesterol transport and increase in plasma FFA. These two denominators (in addition to other individual perturbations of lipid metabolism induced by each arsenical), suggest that in contrast to strengthening a dose-dependent effect phenomenon, the two forms of inorganic arsenic induced lipotoxic and non-lipotoxic dyslipidemia at “low” or “medium” doses and these might be responsible for the cardiovascular and other disease endpoints of inorganic arsenic exposure through drinking water.

Metabolic syndrome: comparison of occurrence using three definitions in hypertensive patients.

Abstract: Metabolic syndrome refers to the clustering or constellation of cardiovascular disease risk factors. The risk factors include elevated blood pressure, dyslipidemia (hypertriglyceridemia, low levels of high density lipoprotein [HDL] cholesterol), hyperglycemia, and central obesity.1,2 Hypertension is a common cardiovascular disease risk factor worldwide.3,4,5 Hypertension frequently coexists with many other cardiovascular disease risk factors such as obesity, dyslipidemia, impaired glucose tolerance (or hyperglycemia), and hyperuricemia.6–10 There are many definitions of metabolic syndrome, as recommended by the various working groups.11–13 However, the core components of the syndrome which include increased waist circumference, impaired glucose tolerance, dyslipidemia, and hypertension, are commonly required by all the various groups for diagnosis.1,11–13 Prevalence of metabolic syndrome varies in different populations and is influenced by several factors including age, race, gender, socio-economic status, work-related activities, and cultural views on body fat.14 Although the various definitions measure similar components, each uses different combinations of cardiovascular disease risk factors. The World Health Organization (WHO) in 1999 made insulin resistance evaluated by the euglycemic study as the pivot for the diagnosis of metabolic syndrome.11,14 The National Cholesterol and Education Program Adult Treatment Panel III (NCEP ATP III), International Diabetes Federation (IDF), and American Association of Clinical Endocrinology (AACE) adopted visceral obesity as the pivot for the diagnosis of metabolic syndrome. However, the European Group for the Study of Insulin Resistance (EGIR) suggested that the underlying etiology in the clustering of cardiovascular risk factors is insulin resistance.11–14 The WHO, NCEP ATP III, and IDF criteria for diagnosis of metabolic syndrome are outlined in table 1▶. Table 1. Definition of metabolic syndrome based on different criteria used. Metabolic syndrome has been associated with an increased tendency to develop type 2 diabetes mellitus and cardiovascular diseases.15–17 The various criteria identify similar sets of people with cardiovascular risk factor clustering. The IDF definition includes a race-specific cut-off for visceral obesity. Abdominal obesity is race- and gender-specific as suggested by many population studies.1,10 Information on the frequency of occurrence of metabolic syndrome in newly diagnosed hypertensive Black African patients is scarce. A comparative analysis of three standard international definitions for diagnosing metabolic syndrome is expected to give an overview of the frequency of metabolic syndrome in a population. The aim of this study was to compare the frequency of occurrence of metabolic syndrome using three standard international criteria/definitions and to study the distribution of cardiovascular risk factors among newly diagnosed hypertensive Nigerians.