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Survey on Avian Malaria Parasites in Village Chickens(Gallus gallus domesticus)in Gombe Local Government Area,Gombe State,Nigeria

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Veterinary Science Research 2021年第2期3卷 7-22页

作者： Jallailudeen Rabana Lawal Umar Isa Ibrahim abdullahi abubakar biu Hassan Ismail Musa Department of Veterinary Medicine Faculty of Veterinary MedicineUniversity of MaiduguriP.M.B.1069MaiduguriBorno StateNigeria Department of Veterinary Parasitology and Entomology Faculty of Veterinary MedicineUniversity of MaiduguriP.M.B.1069MaiduguriBorno StateNigeria Department of Veterinary Public Health and Preventive Medicine Faculty of Veterinary MedicineUniversity of MaiduguriP.M.B.1069MaiduguriBorno StateNigeria

Reports of avian malaria parasites in village chicken in Nigeria generally remain fragmentary and scarce.The study was conducted in Gombe Local Government Area of Gombe State,Nigeria to investigate avian malaria parasites in Village Chickens(Gallus gallus domesticus)and to determine the risk factors associated with the prevalence of the haemoparasites.A total of 530 village chickens blood samples were obtained from apparently healthy village chickens'brachial veins using sterile 2mls syringes and 23 gauge needles.Thin blood smear was made from each blood sample,and Giemsa stained and examined for the presence of avian haemoparasites under an electro-microscope.The result indicates 23.8%overall prevalence rate of three species of avian malaria parasites consisting of Plasmodium,Haemoproteus and Leucocytozoon species.Plasmodium spp.has the highest prevalent rate of 13.0%followed by Haemoproteus spp.(5.1%),mixed Plasmodium spp.+Haemoproteus spp.(4.9%)infection and Leucocytozoon spp.(0.8%).Prevalence of avian malaria parasites was significantly higher in cocks compared to hens(p<0.05),as well as higher in adults compared to growers chickens(p<0.05).This study also showed a higher prevalence of avian malaria parasites during the rainy season compared to the dry season of the study period.It was concluded that haemoparasites of Plasmodium,Haemoproteus and Leucocytozoon species that occur in both single and mixed infections are prevalent among village chickens that are apparently healthy in Gombe Local Government Area of Gombe State,Nigeria.

关键词： Avian Malaria Haemoproteus Leucocytozoon Plasmodium Village chickens

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Toxicity of Radon-222 in Groundwater across Keana in Nasarawa,Nigeria

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Advances in Geological and Geotechnical Engineering Research 2023年第2期5卷 38-49页

作者： abubakar Saidu Bako Usman Rilwan Ibrahim Umar Samson Dauda Yusuf Idris Muhammad Mustapha abdullahi abubakar Mundi Ibrahim Maina Department of Physics Nasarawa State UniversityPMB 1022 KeffiNasarawa StateNigeria Department of Physics Nigerian Army UniversityPMB 1500 BiuBorno StateNigeria Department of Physics Abubakar Tafawa Balewa UniversityPMB 0248 BauchiBauchi StateNigeria

The most common supply of freshwater for drinking,irrigation,and other domestic uses is groundwater;however,because of increased radon concentrations brought on by mining activities,its quality is still a severe concern.Using a liquid scintillation detector,this study investigated the radon content,its related toxicity,and its risk to human health in the groundwater of the Keana in Nasarawa,Nigeria.Ten(10)borehole samples and five(5)well samples totaling fifteen(15)groundwater samples were taken.The results showed that the average radon concentration in water samples from Keana was 2.25 Bq/L.The mean annual effective dosage(ingestion)for adults and children in Keana was 0.016 mSv/y and 0.027 mSv/y,respectively.In Keana,the additional lifetime cancer risk per adult was 5.65×10^(-5),and per child,it was 8.79×10^(-5).The study’s radon concentration was lower than the benchmark of 11.1 Bq/L established in 1991 by the Nigerian Standard Organization and the US Environmental Protection Agency.The results of this study indicate that the level of radon is safe;as a result,people can continue farming and other activities.To reduce the risk of cancer,however,more research could be done in the area.Further research should be done by looking at additional sources in the study area in order to cover the entire zone.Further investigation should be carried out both during the dry and wet seasons because radon concentrations in groundwater alter over time due to dilution by recharge from rainfall.

关键词： Ingestion Inhalation Irrigation Radon Yearly effective dose Excess lifetime cancer risk

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Conjugate Heat Transfer Predictions of Gas Turbine Hot Walls Jets Cooling: Influence of Short Hole Grid Resolutions Using Computational Fluid Dynamics*

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Journal of Power and Energy Engineering 2023年第10期11卷 1-16页

作者： abubakar M. El-Jummah Shehu A. Abdulrahman Alhaji S. Grema Department of Mechanical Engineering University of Maiduguri Maiduguri Nigeria Department of Mechanical Engineering Nigerian Army University Biu Borno Nigeria Department of Chemical Engineering University of Maiduguri Maiduguri Nigeria

Short hole investigations relevant to gas turbine (GT) hot walls cooling heat transfer techniques, were carried out using computational fluid dynamics (CFD) combined with conjugate heat transfer (CHT) code. The CFD software are commercial ones: ICEM for grid modelling and ANSYS Fluent for the numerical calculation, where symmetrical application prevails. The CFD CHT predictions were undertaken for Nimonic-75 metal walls with square (152.4 mm) arrays of 10 holes, whereby the lumped heat capacitance method was applied in order to determine the surface average heat transfer coefficient (HTC), h (W/m2 K) and the dimensionless Nusselt number, Nu. The major parameters considered for the short hole geometries are the pitch to diameter, X/D and length to diameter, L/D ratios and both were varied with range of D values, but X of 15.24 mm and L of 6.35 mm kept constant. Also applied, are variable mass flux, G (kg/s∙m2) and were used in predicting the flow aerodynamics in the short holes. The predictions were for classic thermal entry length into a round hole, as vena contracta, flow separation and reattachment dominates the holes, hence the development of thermal profile through the depth of the GT hot walls. Additionally, the acceleration of the flow along the wall surfaces as it approaches the holes, was a significant part of the overall heat transfer. This was shown to be independent of the hole length, even though the L/D parameter is a critical component to enhanced heat transfer. The CFD CHT predictions showed that validation of the HTC h, Nu and pressure loss, ∆P are in better agreement with measured data and within reasonable acceptance. The ∆P agreement signifies that the aerodynamics were predicted correctly, which is also the reason why the HTC expressed per wall hole approach surface area and Nu were better predicted. This illustrates how effective and efficient the wall internal heat transfer cooling is for gas turbine hot wall heat transfer using airflow jets cooling.

关键词： Lumped Heat Capacitance Thermal Entry Length Symmetrical Application Flow Separation Flow Reattachment

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Experimental Investigation on the Thermal Properties of Gypsum Plaster-Rice Husk Ash Composite

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Open Journal of Composite Materials 2022年第4期12卷 131-138页

作者： Nuhu Caleb Amulah abubakar Mohammed El-Jummah Abba Alhaji Hammajam Usman Ibrahim Department of Mechanical Engineering Faculty of Engineering University of Maiduguri Maiduguri Nigeria Department of Mechanical Engineering Faculty of Engineering Nigerian Army University Biu Nigeria Department of Mechanical Engineering Faculty of Engineering Ramat Polytechnic Maiduguri Nigeria

This experimental investigation aims at evaluating the thermal properties of rice husk ash (RHA)—filled gypsum plaster composite for potential applications, as insulating materials. The thermal conductivities of composites of gypsum plaster reinforced with RHA at 0%, 10%, 20%, 30%, and 40% volume fractions were determined experimentally using Lee’s disc method. The experimental results show that integrating RHA reduces the thermal conductivity of gypsum plaster and improves its insulation capacity. The results obtained from the experiments were compared with the Rule of Mixture Model, Maxwell Model, and Russell Model. It was observed that the thermal conductivities obtained from experiments and the theoretical models decreased with an increase in the volume fraction of RHA. The errors associated with the models with respect to experimental results are on the average of 28.7% for Mixture Rule, 31.6% for Russel Model, and 18.8% for the Maxwell Model. An agricultural waste like RHA can be beneficially used for the preparation of composites and, due to improved insulation capability, these composites can be used for applications such as insulation boards and sheathing, hardboard, ceilings of roofs, decorations, etc.

关键词： Rice Husk Ash Thermal Conductivity Gypsum Plaster Lee’s Disc Method Agricultural Waste

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