Akinlabi O.,Federal University of Technology Akurre |
Stephen E.O.,Waziri Umaru Federal Polytechnic
Acta Metallurgica Slovaca | Year: 2015
The goal of this research was to investigate the influence of zinc and magnesium on the fluidity of Al-Zn-Mg alloy. The fluidity test was carried out using a serpentine-shape sand mould. The length of the serpentine-shape pattern was 180 cm. The experiment was designed by varying the compositions of zinc from 1 to 5 wt%, and magnesium from 0.5 wt% to 2.5 wt%. Variation in compositions of the two elements was done separately, and later a combined variation in compositions of zinc and magnesium was investigated. The superheat temperature was placed at 70ºC above the liquidus temperature. From the results obtained, it was observed that there was general increase in fluidity when the percentage weight composition of magnesium was increased. Alloy with 2.3 wt% Mg was found to have the highest fluidity, followed by alloy with 2.85 wt % Mg. When the percentage weight compositions of zinc were increased, there was a general decrease in fluidity of the Al-Zn-Mg alloy, in which alloy with 5.14 wt % zinc recorded the lowest fluidity of 57.1 cm as compared to the as-cast alloy. Also for the combined variation in compositions of zinc and magnesium, it was discovered that there was decrease in the flow length of the alloy, where alloy with 5.14 wt% Zn and 2.85 wt% Mg combined has flow length of 59.8 cm. But the reduction in fluidity length when the composition of zinc was varied was more drastic as compared to that of the combined alloying elements. © 2015, Technical University of Kosice. All rights reserved.
Muhammad Y.A.,Waziri Umaru Federal Polytechnic |
Lode N.A.,Northern University of Malaysia
Advanced Science Letters | Year: 2015
This study uses a modified equity valuation model (stock price model) to examine the value relevance of balance sheet components (total liabilities (tl), deposit customer liability (dcl) and non-performing loans (npl)) for the periods before and during transition to IFRS in the Nigerian stock Exchange (NSE) Market. A 5-year data of 15 banks listed in the Nigerian stock market is selected as sample for the study. Using stock price model, the tl, dcl and npl measures were transformed into natural log (ln) form to arrive at a compatible and normal data. The results of the model provide evidence that accounting information is value relevant among Nigerian Banks. This is proved from the coefficient of tl and npl that negative but significant in the two periods of NGAAP and IFRS. In contrast, dcl provides a positive but also significant result under the two periods. The result further proves that IFRS is more value relevant than NGAAP. Lastly, we provide evidence from the R2 that there is greater association between accounting information and stock prices during the transition period (IFRS). Besides the significant of findings of this research to security market, the literature is providing contribution to limited market research in African capital market among banks, particularly in Nigeria after the IFRS adoption. © 2015 American Scientific Publishers. All rights reserved.
Adamu N.,Waziri Umaru Federal Polytechnic |
Zubairu I.K.,Ahmadu Bello University |
Ibrahim Y.M.,Ahmadu Bello University |
Ibrahim A.M.,Ahmadu Bello University
Journal of Construction in Developing Countries | Year: 2011
The need for the improved performance and continuous survival of construction firms has caused firms to diversify into other businesses. The purpose of this study is to determine the influence of diversification on the performance of some Nigerian construction firms. Financial statements from seventy construction firms were analysed. The specialisation ratio method was used to measure and categorise the firms into undiversified, moderately diversified and highly diversified firms, and profitability ratios were used to measure the group-wise performance of the firms. The Student t-test was used to test the relationship between the extent of diversification and performance. The findings reveal that undiversified firms outperform the highly diversified firms in terms of Return on Total Assets and Profit Margin. Similarly, the moderately diversified firms were found to outperform the highly diversified firms in terms of Return on Equity, Return on Total Assets and Profit Margin. However, no performance difference was found between the undiversified firms and the moderately diversified firms based on the three measures used. A nonlinear relationship was found between the extent of diversification and performance. It was concluded that diversification does not necessarily lead to an improvement in profitability. The implication is that firms are better-off remaining focused if the aim is to improve financial performance. © Penerbit Universiti Sains Malaysia, 2011.
Suleiman I.Y.,Waziri Umaru Federal Polytechnic |
Yaro S.A.,Ahmadu Bello University |
Abdulwahab M.,Ahmadu Bello University
Asian Journal of Chemistry | Year: 2016
The ethanolic extract of Acacia senegalensis (gum arabic) stem was used as corrosion inhibitor for mild steel in 0.5 M H2SO4 using gravimetric-weight loss and potentiodynamic polarization. The characterization of the coupon before and after the corrosion test was done using scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM/EDS). The temperature, inhibitor concentration and time were varied in the range of 30-70 °C at 20 °C interval, 0-10 % v/v at 2 % v/v interval and 45 to 270 min at 45 min interval, respectively. The synergetic effect of the inhibitor was evaluated by addition of halide ion (KI-). Corrosion rate increased with increase in temperature and decreased with increase in both inhibitor concentration and time. Inhibition efficiency was found to increase with increase in concentration of the extract and the maximum inhibition efficiency was found to be 94.16 %, maximum inhibition efficiency in the presence of KI was 99.62 % and was assumed to occur via adsorption of the inhibitor molecules on the metal surface. The adsorption of the molecules of the extract on the mild steel surface obey Langmuir adsorption isotherm. The potentiodynamic polarization results revealed that the extract acts as mixed type inhibitors.
Idris A.,Ahmadu Bello University |
Muhammad N.A.,Waziri Umaru Federal Polytechnic
Jordan Journal of Civil Engineering | Year: 2014
This paper was aimed at the EN338 (2009) strength classification of some common Nigerian timber species, namely; Strombosia pustulata, Macrocarpa bequaertii, Nauclea diderrichii and Entandrophragma cyclindricum. Twelve (12) timber planks from the selected species were supplied from Ekiti state in the southern part of Nigeria. The specimens for experimental measurements were prepared from the obtained timber planks. Laboratory experiments were conducted to determine the physical and mechanical properties of the selected timber species in accordance with EN408 (2003). The mechanical properties were determined using four point bending test. The generated properties were used to obtain the characteristic values of the material properties in accordance with EN384 (2004). The selected timber species were then graded in accordance with EN 338 (2009). Strombosia pustulata, Macrocarpa bequaertii, Nauclea diderrichii and Entandrophragma cyclindricum were assigned to strength classes D35, C14, D30 and D18, respectively. Other properties such as tensile and compressive strengths parallel and perpendicular to grains, shear strength as well as shear modulus were computed from the empirical relationships given in EN 338. © 2014 JUST. All Rights Reserved.