160 research outputs found

    Cr-doped La-Ni-O catalysts derived from\ua0perovskite precursors for CH4-CO2 reforming under microwave irradiation

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    The nickel catalysts derived from Cr-doped LaNiO perovskite-like precursors were characterized by X-ray diffraction, high-resolution transmission electron microscopy, temperature-programmed oxidation, temperature-programmed reduction, and X-ray photoelectron spectroscopy. Their catalytic performance in CO reforming of methane under microwave irradiation was investigated. It was found that the structure and morphology of the oxide composites in this research were influenced by the ratio of Ni and Cr, and the mismatch of La, Ni, and Cr may cause phase segregation. The catalytic performance of the Ni catalysts is dependent on the oxygen mobility of the perovskite oxide matrix, the content of the reduced Ni, and the content of the remaining perovskite structure. The mobile oxygen in the perovskite matrix in the catalyst may enhance the conversion of CO during the reaction

    ETHYLATION OF BENZENE OVER DIFFERENT ZEOLITE CATALYSTS

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    Determination of Optimal Crew Size in Project Segmentation to Minimize Cost

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    Stakeholders and contracting board have begun to utilize innovative contracting methods that provide new incentives for reducing construction duration. These methods have placed increasing pressure on decision makers in the construction industry to search for an optimal construction plan that minimizes construction time and cost while preserving quality. This paper considers the problem of finding the optimal number of segment(s) that minimizes total project cost of a non-homogenous road construction project located in a city in South West, Nigeria. A mathematical programming model approach was adopted to obtain the optimal number of segments as opposed to when the activities of the project are scheduled sequentially. Also, Binary interaction matrix (BIM) was used to define stated relationships between fixed and variable quantities of the cost and duration respectively. Given stipulated due date of 8 months with a penalty / bonus of N 63091791/month. The analysis shows that the optimal number of segments into which the project can be divided into is three and that by working in parallel the project will be completed in 5 months at a cost of N1,409,609,413. This is opposed to the original contract lump sum of  N 1, 577, 294, 775 with a normal duration of 12 months. A saving of 1.55% was realized. This work demonstrated the possibility of dividing a continuous repetitive project into a numbers of segments of equal work content, working in parallel, using optimum crew size such that the duration and the total cost of the project can be minimized. Key words: Project Management, Scheduling, Construction planning, Natural Rhythm, Project Segmentatio

    ETHYLATION OF BENZENE OVER DIFFERENT ZEOLITE CATALYSTS

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    Developing Flood Resilient Buildings in Nigeria: A Guide

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    Acknowledgements We acknowledge the support of the UI Ibadan TETFUND IBR 2016 Research Project Fund. Abstract Recently, the damage caused by flood in Nigeria has become unbearable leading to series of economic losses. Several post flood measures taken has proved to be inadequate because they are temporary. Hence, the needful is the flood risk management. Managing the risk of flood can be achieved by enhancing the resilient of the buildings in Nigeria. This requires a pragmatic approach from the concerned stakeholders. In this paper, we observed and discussed some of the drawbacks in Nigeria buildings leading to its vulnerability to flood. Also, guide was developed for government and stakeholders to achieve the incorporation of resilience in Nigeria building and its environment. Expected resilience was proposed and a flowchart to assist the prospective builders was developed. This will assist in developing the necessary blueprint towards achieving this goal. Necessary suggestions made will aid in the actualization of a resilient buildings within Nigeria. Keywords: Flood, resilience, Nigeria, flood risk management, buildin
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