Numerical modelling of copper composite thin films for solar control filter

Performance of solar control filter depends strongly on the individual layer thicknesses as well as the quality of their interfaces. In this work, a numerical modeling was designed and implemented to optimize the layer thicknesses of Cu2O/CuS, Cu2O/Cu and CuS/Cu thin films for use as solar control filter using transfer matrix. The result shows that for Cu2O/CuS, with CuS in contact with the substrate, the optimized layer thickness of 110/30nm and for CuS/Cu and Cu2O/Cu with Cu in contact with the substrate, the optimized layer thickness are 110/30nm and 100/30nm, respectively. The model also predicted transmittances of 67% for Cu2O/CuS, 42% for CuS/Cu and 64.5% for Cu2O/Cu at 550nm. A transmittances of 24.9-36.9% of IR radiation for all the films was realized. These results, when compared with previous works indicate the possibility of improvement in the performance of the filters.Keywords: Solar Control Filter, Transfer Matrix, Infrared, Numerical Modeling, Transmittanc

Investigation of the inhibition efficiency of Irish potatoes leaves extract on aluminium sheet in acidic medium

Aluminium is the most widely used non-ferrous metal, hence there is need to protect it from corrosion. This research work, investigated the inhibitive property of the ethanol extract obtained from Irish potato leaves (Solamun tuberosum) for aluminium corrosion using 2M H2SO4 as a medium. The inhibitive effect of the extract against the corrosion of aluminium was investigated using gravimetric technique at various concentrations of the extract (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 g/L). The results revealed that with increase in concentrations of the extract, the corrosion rate decreases and the highest inhibition efficiency was found to be 77.78% at 4.0 g/L of the extract. Additionally, the adsorption of the extract on the aluminium surface was found to obey Langmuir’s adsorption isotherm. However, the plant extract proved to be effective inhibitor on the corrosion of aluminium in the acid medium and can be used as green inhibitor

Dietary supplement using cockroach meal: impact on growth indices and biochemical responses in hybrid catfish

Globally the need to substitute fishmeal with other animal protein sources in the fish diet has gained more attention; which is occasioned by the increasing cost of fish. A 12-week trial was conducted to ascertain the growth indices and biochemical response of hybrid catfish (Clarias gariepinus(♀) and Heterobranchus bidorsalis (♂)) fed cockroach meal supplement. A total of 800 hybrid catfish were randomly distributed into four dietary treatments (Diet A- control feed), Diet B (50 % cockroach and 50 % fishmeal), Diet C (100 % cockroach meal) and Diet D (100 % fishmeal). Each treatment was replicated with 35 fish per experimental pond in a completely randomized design. Progressive weight gain was determined bi-weekly. At the end of the study period, fishes were randomly sacrificed for proximate compositions and plasma biochemical analyses (glucose, triglyceride, cholesterol, total protein, albumin) using standard protocols. The study revealed that growth parameters (Weight gain, Average weight gain, Protein efficiency ratio, Feed Conversion rate, Specific growth rate and Survival rate (SR) were influenced by the dietary treatments (p>0.05). The highest weight gain was recorded in Diet 1 (8847.73±292.65 g) > Diet 2 (7816.33±121.71 g)>Diet 3 (7811.67±566.08 g) >Diet 4 (7022.00±44.193 g). Similarly, the best feed conversion ratio was found in fish fed Diet A (10.12±0.01),>Diet B, C and D had the same values of 0.11 g respectively. There was no significant (p>0.05) difference in plasma biochemical indicators measured when compared to the control (Diet A). Thus, indicating that all the fish were healthy and had normal physiological activities. Cockroach meal can therefore, be used as a feed supplement without having any adverse effect on the growth and well-being of hybrid catfish fingerling

Impact of Gurara Dam on Land Cover in the Surrounding Communities of Kaduna State, Nigeria

This research focuses on the impact of Gurara Dam on land cover in the surrounding communities of Kaduna state Nigeria. The aim of the study is to assess changes land cover condition in communities surrounding Gurara Dam as a result of the Dam construction. This was achieved by analysing the land cover changes between pre-dam (2000) and the post-dam (2013) in terms of spatial extent and percentage coverage.To assess the impact, Landsat (ETM, TM and MSS) covering the area for 2000 (pre-dam period) and 2013 (post-dam period) was obtained. To interpret and verify the accuracy of the satellite imagery; ground truth observation was conducted on the land cover of the study area. Using ArcGIS 10.0 and AutoCAD Map 2013 software, different image processing techniques and analysis were undertaken to produce land cover maps of the study area for pre-dam and post dam period. The extent of area coverage of each land use/land cover was calculated in hectares and express in percentages. The study discovers that in the post-dam period (between 2000 and 2013) the impact of Gurara dam has resulted in substantial changes in the land cover, with losses in fadama land. Forestry, arable land and Rock outcrop by 58%, 9%, 7%, and 12% respectively. Whereas gains occurred in bare land (26%), water bodies (42%), circulation (28%).  Modern irrigation also witnessed gain by 100% and built up area 26%. It is there recommended that, modern technology (Geographic Information System) be provided as mitigation measure to land cover problems in communities surrounding Gurara Dam. Keywords: Dam Construction, Geographic Information System, land cover, Upstream and Spatial Exten

Infections Mimicking Malignancy in Kano, Nigeria: A Teaching Hospital Experience

Objective: This study aimed to evaluate the pattern of presentation of infectious lesions mimicking malignancy. This will serve to heighten clinical indices of suspicion and prevent unwarranted aggressive management. Methods: This is a 19-year (1999-2017) audit review of all morphologically diagnosed infection-related lesions in which malignancy was primarily clinically suspected. Results: Fifty-six cases of infection-related mimics of malignancy were diagnosed in the study period: schistosomiasis related, 22 (39.2%); actinomycosis, 21(37.5%); tuberculosis-related, 10 (17.9%); fungi-related, 3(5.4%). Twenty-one cases of actinomycosis of the lower limbs and oropharynx were mistaken for melanoma, squamous cell carcinoma, sarcoma, and oropharyngeal carcinoma. The mean age was 33±17years.The 10 patients with atypical Mycobacterium tuberculosis-mimicking malignancy had mean age of 37±14 years and included three in the testes, testicular cases, one from the jaw, and two cases each from ovary, breast, and uterus. Of the three fungal lesions, there was a case each from the brain, skin, and bone. All were males with mean age of 21±7 years. Conclusion: For accurate diagnosis of infection-related mimics of malignancy, a high index of clinical suspicion, knowledge of and attention to characteristic radiological signs, and obtaining representative tissues for histopathologic and cytopathologic diagnoses are paramount

Water Quality Assessment of Some Selected Hand Dug Wells and a Borehole in North Eastern Parts of Bauchi Metropolis, Nigeria

Water samples were taken from six hand dug wells and a borehole for physico-chemical and microbial analysis to ascertain its quality, type and suitability for domestic, livestock and irrigation purposes. The ranges of results of the physico-chemical parameters are: temperature (28-31.5)oC, Conductivity (170-650)µs/cm, turbidity (1.0-90.8)NTU, and pH(7.0-8.5). Other chemical parameters include: cations -  Ca2+(25.6 – 72.0)mg/l , Na+(23.1 – 75.87)mg/l, K+(0.14 – 78.3)mg/l, Mg2+(1.46 – 20.75)mg/l, Fe2+(0.0 – 1.1)mg/l, Cu2+(0.0 – 0.49)mg/l, Zn2+(0.00 – 1.74)mg/l, Pb2+(0.00 – 0.001)mg/l, Cr6+(0.00 – 0.02)mg/l and anions – HCO3-(54.0 – 140.0)mg/l, Cl-(32.5 – 114.96)mg/l,  F-(0.23 – 0.77)mg/l,  CO32-(32.4 – 84.0)mg/l, SO42-(10.31 – 121.0)mg/l,  NO3-(1.08 – 75.7)mg/l, NO2-(0.013 – 0.69)mg/l. Data values analyzed from the results obtained indicate the water to be Ca-HCO3, K-HCO3, Mg-HCO3 and Na-Cl water type containing high concentrations of some major, minor and trace cations and anions which fall above the maximum permissible limits of the National Standard for Drinking Water Quality (NSDWQ) of Nigerian Industrial Standard (NIS), 2007. Physical and microbiological parameters indicate that the water is turbid and contain a high total coliform counts above the NIS set standards for maximum permissible limits. This may be attributed to proximities of soakaways and dumpsites to the wells which may need to be monitored from time to time. The water was also found to be suitable for irrigation. Keywords: Water Quality, Water Type, Irrigation Wate

Effect of Dietary Replacement of Maize with Yam and Irish potato peel meals on the Growth and Economic Performance of Growing Rabbits

An eight-week feeding trial was conducted to investigate the effect of feeding yam and irish potato peel meals on the growth performance and economic analysis of cross-bred (Dutch x New Zealand white) growing rabbits aged between five to seven weeks. Thirty rabbits were randomly allocated to six dietary treatments with five rabbits per treatment. Diets 1, 2, 3, 4, 5 and 6 contained 100% maize, 50% maize and 50% yam peel meal, 50% maize and 50% irish potato peel meal, 50% yam peel meal and 50% irish potato peel meal, 100% yam peel meal and 100% irish potato peel meal, respectively. The response showed that the growth parameters were not significantly (P>0.05) different among the treatment groups except mean final body weight which was significantly (P>0.05) different. The mean final body weight of rabbits fed T3 diet (50% maize and 50% irish potato peel meal) was significantly (P< 0.05) higher than those fed T2 (50% maize and 50% yam peel meal) and T6 (100% irish potato peel meal) diets, but were similar (P>0.05) to other diets. However, the lowest mean final body weight was obtained in rabbits fed T6 (100% irish potato peel meal) diet. The cost per kg feed decreased progressively as the levels of yam and irish potato peel meals increased in the diets. The cost per kg gain also declined from  ₦ 249.59 in T1 (100% maize) to ₦ 181.95 in T4 (50% yam peel meal and 50% irish potato peel meal), which showed the best cost per kg weight gain. The study demonstrated that the yam and irish potato peel meals can replace maize up to 100% as energy source for growing rabbits without adverse effect on performance.Keywords: Growth Performance, Yam and Irish Potato peel meals, Economic Analysi

Modified low energy adaptive clustering hierarchy protocol for efficient energy consumption in wireless sensor networks

In this paper, we propose a Modified Low-Energy Adaptive Clustering Hierarchy (MoLEACH) protocol to improve energy consumption in in Wireless Sensor Networks. The novelty of MoLEACH is that, unlike the original LEACH that uses the residual energy of the network, it considers the residual energy of each node for calculation of the threshold value for the next round in cluster head selection. We make comparative simulation analysis between the MoLEACH and LEACH in testing different parameters such as first node dead, half node dead, and the effect of the number of nodes to the network lifetime. The simulation results show that the number of nodes affects the network lifetime in which increments of number of nodes decrease the network lifetime. In small area, minimum number of nodes is better for network lifetime in both MoLEACH and LEACH protocols. Hence, MoLEACH shows improvement of energy efficiency over the LEAC

Impact of Device Parameter Variation on the Electrical Characteristic of N-type Junctionless Nanowire Transistor with High-k Dielectrics

Metallurgical junction and thermal budget are serious constraints in scaling and performance of conventional metal-oxide-semiconductor field-effect transistor (MOSFET). To overcome this problem, junctionless nanowire field-effect transistor (JLNWFET) was introduced. In this paper, we investigate the impact of device parameter variation on the performance of n-type JLNWFET with high-k dielectrics. The electrical characteristic of JLNWFET and the inversion-mode transistor of different gate length (LG) and nanowire diameter (dNW) was compared and analyzed. Different high-k dielectrics were used to get an optimum device structure of JLNWFET. The device was simulated using SDE Tool of Sentaurus TCAD and the I-V characteristics were simulated using Sdevice Tools. Lombardi mobility model and Philips unified mobility model were applied to define its electric field and doping dependent mobility degradation. A thin-film heavily doped silicon nanowire with a gate electrode that controls the flow of current between the source and drain was used. The proposed JLNWFET exhibits high ON-state current (ION) due to the high doping concentration (ND) of 1 x 1019 cm-3 which leads to the improved ON-state to OFF-state current ratio (ION/IOFF) of about 10% than the inversion-mode device for a LG of 7 nm and the silicon dNW of 6 nm. Electrical characteristics such are drain induced barrier lowering (DIBL) and subthreshold slope (SS) were extracted which leads to low leakage current as well as a high ION/IOFF ratio. The performance was improved by introducing silicon dioxide (SiO2) with high-k dielectric materials, hafnium oxide (HfO2) and silicon nitrate (Si3N4). It was found that JLNWFET with HfO2 exhibits better electrical characteristics and performance