660 research outputs found

    Prediction of Natural Gas Compressibility Factor in a Single-Phase Gas Reservoir: A Comparative Study

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    Natural gas compressibility factor plays important roles in pipeline design, reserve estimation and gas metering. The aim of this study is to presents the most accurate and reliable method of computing gas compressibility factor in a single-phase gas reservoir at various reservoir pressures. In this study, the gas compositions and the specific gravity of the respective gas compounds were retrieved from literatures. This specific gravity determine the pseudo critical and the pseudo reduced properties (temperature and pressure) of the respective gas compounds being studied. The predicted methods studied are Papay correlation, Hall-Yarborough equation of state (EOS), viral EOS, Beggs and Brill and Dranchuk-Abu-Kassem correlation. The methods are expressed as functions of the pseudo-reduced temperature and pressure, thereby predicting the compressibility factor of the predicted methods. The accuracy and the performance of the methods were tested by comparing the results obtained from the methods studied with experimental z-factor values obtained from the literatures. The experimental z-factor values were set as standard for the predicted methods studied. Six (6) statistical parameters and various charts (line and column charts) were used to attest the effectiveness and the precision of the methods. The statistical tools are average absolute error (AAE), average absolute relative error (AARE), root mean square error (RMSE), residual sum of square (RSS), mean square error (MSE) and coefficient of determination (R2). The results of the study shows that, the Papay correlation has the highest coefficient of regression, R2= 92%, rated as the most accurate, reliable and best method. The Hall-Yarborough equation of state has R2 of 86%. The Viral equation of state has R2 of 83%. The Beggs and Brill correlation has R2 of 42%. The Dranchuk-Abu-Kassem correlation has R2 of 10.5%. The Beggs and Brills correlation method is not suitable for application, if the pseudo-reduced pressure is less than 0.92. The Dranchuk-Abu-Kassem correlation is only applicable, if the pseudo-reduced properties are within the range of 0.2<Ppr<15, 1.0<Tpr<3.0. The Hall-Yarborough equation of state cannot be used if the pseudo-reduced temperature is less than one

    PRIMITIVITY OF PERFECT RESIDUUM OF PERMUTATION GROUPS

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    In this paper, the construction of permutation groups which include symmetric groups, alternating groups, dihedral groups and the groups generated by the semidirect product (wreath products) of two permutation groups. The perfect residuum of the constructed groups has been obtained and their primitivity status has been investigated which enable us to formulate some results on such properties concerning the groups. A standard computer program, Groups algorithm and programming (GAP) has been employed in enhancing and validating the result obtained. Keywords: Primitive groups, Perfect Residuum, permutation groups

    Effects of biochar amendments on rice growth and metabolic response to salinity stress in salt-affected soils

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    Exploring cheaper and sustainable strategies for managing salt-affected soils remains crucial in irrigated areas. Many researchers recommended using gypsum as material for reclamation salt-affected soils, which are costly and unavailable for most farmers. In this study, we used biochar derived from the common materials found in the irrigated areas that are locally available and less utilized as a substitute for gypsum for sustainable reclamation of salt-affected soils. Salt-affected soils (saline, saline-sodic and sodic) and unaffected were collected from the Watari Irrigation project, Kano State Nigeria using farmers' perceptions about the salinity situations of the irrigation scheme and existing legacy map data. The biochar used for this study were made using the Typha grass, rice straw, and rice bran samples collected from the same area. Thirty-six (36) containers (plastic pots) with a diameter of 27.5cm and height of 45cm each were filled with eight-kilogram dried soils, including non-saline, saline, and saline-sodic. We measured plant height, and normalized difference vegetation index (NDVI) at interval of 14 days. Number of tillers per plant were also measured during tillering stage at interval of 14 days. Stover dry weight, grain dry weight, electrolytic leakage and proline contents were measured after the end of the experiment. The results revealed a high significant effect (p<0.01) of biochar amendments in remediating different forms of salt affected soils. Saline sodic soil was effectively managed when using Typha biochar with a mean value very close to non-saline soil. Rice straw and rice bran reduces the salinity levels particularly in sodic soil. Therefore, biochar from different source could be used in addressing salt-specific problems rather than using a uniform treatment

    Detection of antibodies to avian influenza, infectious bronchitis and Newcastle disease viruses in wild birds in three states of Nigeria

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    This study aimed at determining the possible exposure of wild birds to avian influenza (AI), infectious bronchitis (IB) and Newcastle disease (ND) viruses. Apparently healthy species of free flying wild birds were captured using locally-made baited traps set at strategic watering and feeding locations and in poultry farms. Few species of captive wild birds in households and live bird markets (LBMs) were also sampled. Sera from blood samples collected were analyzed for antibodies to AI, IB and ND viruses using enzyme linked immunorsorbent assay (ELISA). Out of the 209 sera analysed, Bubulcus ibis was 24%, 70% and 27% while Psittacus erithacus was 7%, 21% and 7% positive for antibodies to AI, IB and ND viruses, respectively. Branta canadensis, was 35% and 64% positive for antibodies to AI and IB viruses. Balearica regulorum and Numidia maleagris were 100% and 9% positive to AI virus antibodies. Free flying birds were 19 (15%), 57 (45%) and 27 (21%) positive while captive wild birds were 11%, 20% and 14% positive to AI, IB and ND viruses antibodies, respectively. The results of this study confirm that wild birds were exposed to AI, IB and ND viruses. There was co-exposure of some wild bird species to AI, IB and ND viruses. These birds could possibly serve as carriers and disseminators of AI, IB and ND to poultry. Therefore, control measures against these important poultry diseases should include incursion of wild birds.Keywords: Avian influenza, Infectious bronchitis, Newcastle disease, Nigeria, Wild bird

    Comparative Study on the Natural and Synthetic Hormones ofClarias gariepinus Broodstock

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    The study was carried out for six (6) weeks at the Department of Fisheries Teaching and Research farm, Modibbo Adama University, Yola, to compare the reproductive performance of Clarias gariepinus using synthetic (ovaprim) and natural (C. gariepinus pituitary extract) hormones . At the end of the feeding trial, the fecundity, percentage fertilization, hatchability, and survival rates of the hatchlings were estimated using standard procedure. The hatchlings were further raised for six weeks and the increase in weight was determined. The results showed that female broodstock injected with C. gariepinus pituitary extract (CgPE) had a higher fecundity (124,000) while the female injected with Ovaprim had 65,000 eggs. The weight of the testes significantly differed (p<0.05) across the treatments, the right lobe weighed 1.63g while the left lobe weighed 1.98g . Subsequently, a higher fertilization rate was recorded in CgPE (91.1%) while Ovaprim had 85.55% . However, Ovaprim had a higher percentage hatchability of 82.93% while CgPE had 82.73% . At the end of the six (6) weeks feeding period, the survival rate was higher in the fish treated with CgPE (82.31%) while the fish injected with Ovaprim had 79.68% . The research exposed the efficacy of using CgPE in the absence of synthetic hormone, CgPE is a preferred substitute that Hatchery managers can utilize for fingerlings production

    Adsorption of Congo Red Dye from Aqueous Solution using ZnO and Al2O3/ZnO Composite: Isotherm, Kinetic and Thermodynamic Data

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    Herein, an adsorption study of congo red (CR) dye onto ZnO and Al2O3/ZnO  is reported. ZnO was prepared using conventional chemicals by co-precipitation method and Al2O3 used in the composite was prepared through recycling of aluminium waste. Information about the materials was obtained through spectroscopic techniques. A batch adsorption method was used to obtain the adsorption data from which isotherm, kinetic and thermodynamic parameters were obtained. The result of the adsorbents characterisation revealed the expected properties of the prepared materials. The adsorption capacities at 250 mg/L of CR dye were 24.33 mg/g and 24.57 mg/g for ZnO and Al2O3/ZnO respectively. The isotherm study of the adsorption process revealed that Langmuir model fitted best the adsorption data with monolayer adsorption capacities (qm) of 27.67 mg/g and 33.39 mg/g for ZnO and Al2O3/ZnO respectively. The adsorption was rapid within the first 15 min and the equilibrium was reached at 45 min. The kinetic study followed a pseudo-second-order model with the rate constant of 0.049 and 0.093 g.mg-1.min-1 for ZnO and Al2O3/ZnO  respectively. Experimentally, the process was endothermic and was supported by the positive values of enthalpy (ΔH) with positive values of entropy (ΔS). The change in free energy (ΔG) is negative at all temperatures studied, indicating spontaneity but more spontaneous for Al2O3/ZnO than ZnO. The adsorption of CR dye from an aqueous solution onto ZnO as an adsorbent can be slightly improved upon by the introduction of Al2O3 to form Al2O3/ZnO composite

    High mortality among tuberculosis patients on treatment in Nigeria: a retrospective cohort study.

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    BACKGROUND: Tuberculosis (TB) remains a leading cause of death in much of sub-Saharan Africa despite available effective treatment. Prompt initiation of TB treatment and access to antiretroviral therapy (ART) remains vital to the success of TB control. We assessed time to mortality after treatment onset using data from a large treatment centre in Nigeria. METHODS: We analysed a retrospective cohort of TB patients that commenced treatment between January 2010 and December 2014 in Aminu Kano Teaching Hospital. We estimated mortality rates per person-months at risk (pm). Cox proportional hazards model was used to determine risk factors for mortality. RESULTS: Among 1,424 patients with a median age of 36.6 years, 237 patients (16.6%) died after commencing TB treatment giving a mortality rate of 3.68 per 100 pm of treatment in this cohort. Most deaths occurred soon after treatment onset with a mortality rate of 37.6 per 100 pm in the 1st week of treatment. Risk factors for death were being HIV-positive but not on anti-retroviral treatment (ART) (aHR 1.39(1 · 04-1 · 85)), residence outside the city (aHR 3 · 18(2.28-4.45)), previous TB treatment (aHR 3.48(2.54-4.77)), no microbiological confirmation (aHR 4.96(2.69-9.17)), having both pulmonary and extra-pulmonary TB (aHR 1.45(1.03-2.02), and referral from a non-programme linked clinic/centre (aHR 3.02(2.01-4.53)). CONCLUSIONS: We attribute early deaths in this relatively young cohort to delay in diagnosis and treatment of TB, inadequate treatment of drug-resistant TB, and poor ART access. Considerable expansion and improvement in quality of diagnosis and treatment services for TB and HIV are needed to achieve the sustainable development goal of reducing TB deaths by 95% by 2035

    Effects of zinc oxide nanoparticles on viscosity of transesterified neem oil

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    Efforts have been made worldwide to find alternative fluids for industrial applications. Vegetable oil appears to be a perfect alternative, but using most of the vegetable oil as a feedstock made its use for industrial purposes challenging. The recent trend is to develop coolants/lubricants from non-edible seed oil. This work investigates the effects of zinc oxide nanoparticles on viscosity of transesterified neem oil. The crude neem oil was purified, transesterified and nanoparticles were dispersed in the transesterified oil at concentrations ranging from 0.0% to 1.0% at 0.2% intervals. Fourier Transform Infrared (FTIR) spectra were used to examine the structures of the samples and Scanning Electron Microscopy (SEM) analyses were used to examine the surface morphology of the samples. Viscosity were examined. Among other things, it was found that a small amount of ZnO (0.6%) nanoparticles in the oil could improve the viscosity of the fluid. The nanoliquid with a ZnO concentration of 0.6% appears to have optimal properties

    Challenges of Immunization Coverage among a Semi-Nomadic Population in Kano State, North West Nigeria

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    Nigeria has been reported to be off track in achieving the 4th Millennium Development Goal (Reducing Child Mortality) due to poor health indicators such a

    The cost of illness for childhood clinical pneumonia and invasive pneumococcal disease in Nigeria.

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    BACKGROUND: Pneumococcal disease contributes significantly to childhood morbidity and mortality and treatment is costly. Nigeria recently introduced the pneumococcal conjugate vaccine (PCV) to prevent pneumococcal disease. The aim of this study is to estimate health provider and household costs for the treatment of pneumococcal disease in children aged <5 years (U5s), and to assess the impact of these costs on household income. METHODS: We recruited U5s with clinical pneumonia, pneumococcal meningitis or pneumococcal septicaemia from a tertiary level hospital and a secondary level hospital in Kano, Nigeria. We obtained resource utilisation data from medical records to estimate costs of treatment to provider, and household expenses and income loss data from caregiver interviews to estimate costs of treatment to households. We defined catastrophic health expenditure (CHE) as household costs exceeding 25% of monthly household income and estimated the proportion of households that experienced it. We compared CHE across tertiles of household income (from the poorest to least poor). RESULTS: Of 480 participants recruited, 244 had outpatient pneumonia, and 236 were hospitalised with pneumonia (117), septicaemia (66) and meningitis (53). Median (IQR) provider costs were US17(US17 (US14-22) for outpatients and US272(US272 (US271-360) for inpatients. Median household cost was US51(US51 (US40-69). Overall, 33% of households experienced CHE, while 53% and 4% of the poorest and least poor households, experienced CHE, respectively. The odds of CHE increased with admission at the secondary hospital, a diagnosis of meningitis or septicaemia, higher provider costs and caregiver having a non-salaried job. CONCLUSION: Provider costs are substantial, and households incur treatment expenses that considerably impact on their income and this is particularly so for the poorest households. Sustaining the PCV programme and ensuring high and equitable coverage to lower disease burden will reduce the economic burden of pneumococcal disease to the healthcare provider and households
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