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  • Impacts of Manpower Training and Development on Productivity of Workers in an Organization: A Study of Selected Firms in Enugu: Access Bank Plc, Nigerian Breweries Plc, First Bank Plc, Emenite Limited Nigeria Bottling Company Ltd]

    This project is on Impacts of Manpower Training and Development on Productivity of Workers in an Organization: A Study of Selected Firms in Enugu: Access Bank Plc, Nigerian Breweries Plc, First Bank Plc, Emenite Limited Nigeria Bottling Company Ltd]

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  • DESIGN AND IMPLEMENTATION OF AN ONLINE BOOKING RESERVATION SYSTEM

    This research is on Design and implementation of an online booking reservation system.

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  • THE ROLE OF ADVERTISING ON THE PERFORMANCE OF SALES OF BEVERAGES IN NIGERIA (CASE STUDY: NIGERIAN BREWERIES LIMITED)

    This project is on the role of advertising on the performance of sales of beverages in Nigeria  (case study: Nigerian breweries limited).

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  • LEVELS OF POLYCYCLIC AROMATIC HYDROCARBON IN FRESH WATER FISH DRIED UNDER DIFFERENT DRYING REGIMES

    ABSTRACT

    Levels of polycyclic aromatic hydrocarbon in fresh water fish dried under different drying regimes. Preservation of fish by drying over different types of heat regimes have been known. However, there has not been a comprehensive comparison in terms of the possible contamination associated with these drying regimes. This work was set to evaluate the levels of PAHs that are likely to accumulate in the bodies of fresh water fishes dried under heat from charcoal, sun (sun drying), electric oven and polythene augmented drying regimes (burning of used cellophone materials). The levels of sixteen PAHs were determined in fish samples harvested from Otuocha River in Anambra State, Nigeria. The fish samples were dried, pulverized and subjected to soxhlet extraction using n-hexane at 600c for 8hrs. The water content of the eluants were further removed with florisil clean-up before Gas chromatographic ? mass spectrometric analysis. Results obtained showed that sun-dried fish had PAHs concentration to be 35.7+ 0.2‘g/g; oven dried gave 47.7+ 0.2‘g/g and charcoal dried 79.53+ 0.2‘g/g, while drying with firewood resulted in 188.1+ 0.2‘g/g. Charcoal drying augmented with polythene resulted into PAHs level of 166.2+ 0.1‘g/g while fish dried under heat generated from burning firewood and polythene material resulted into PAHs concentration of 696.3+0.2‘g/g. Preliminary analysis of the fresh water samples and the undried fish samples (control) revealed that the fresh water contained total PAHs level of 2.86+ 0.1‘g/ml, while the fresh fish 4.97+ 0.2‘g/g. The concentration of PAHs in all the dried fish under different drying agents were significantly higher than the control. The result is more worrisome in that even the fishes dried under the sun have PAHs significantly higher than that of the control (p<0.05). It is apparent that the increase in PAHs must have come from the environmental PAHs (exposure) under which the fishes were dried (under sun). For the other drying regimes, in which the levels of PAHs were significantly higher than that of sun-dried, it can be concluded that the excessive PAHs in the body of the dried fish were from the ?burning? or drying agents. More significantly are the observed very high increase in PAHs when drying was augmented with polythene, an agent known to be a high source of PAHs when incinerated. Consumers of dried fish should therefore beware of the dried fish they purchase from the local market.

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  • ISOLATION, PURIFICATION AND CHARACTERIZATION OF FREE AND IMMOBILIZED ALPHA-AMYLASE FROM BACILLUS LICHENIFORMIS

    ABSTRACT

    This research is on Isolation, purification and characterization of free and immobilized alpha-amylase from bacillus licheniformis. The bacteria Bacillus licheniformis was cultured in nutrient agar and then incubated for 15h at 35oC. The bacteria cells were harvested by centrifugation after incubation. The cell free supernatant was used to estimate alpha-amylase activity. The alpha-amylase obtained was isolated and purified using ammonium sulfate precipitation, gel filtration and ion exchange chromatography. It was purified up to 15.5 fold and a yield of 20.2% on DEAE- Sephadex column with a final specific activity of 12.14 u/mg. The alpha-amylase was immobilized by entrapment in calcium alginate beads. The free and immobilized enzyme had broad temperature ranges from 20oC to 70oC with optima of 60oC and 70oC respectively and optimum pH of 7.0 and 8.0 respectively. Initial velocity studies for the determination of kinetic constants with maltose as substrate revealed a KM value of 2.5 mg/ml and 1.0 mg/ml for the free and immobilized enzyme respectively and a Vmax value of 0.4unit/mg/min and 0.95unit/mg/min for the free and immobilized enzyme respectively. Both the free and immobilized enzyme activity were enhanced by Ca2+ , Mn2+ , and Na+ while Hg2+ and Zn2+ were found to be strong inhibitors of both the free and immobilized enzyme.

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