• Journal of Environmental Science International
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• v.1 no.1
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• pp.11-17
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• 1992

The treatment performances of anaerobic-aerobic activated sludge Process were investigated under various operation conditions. The treatment system proposed in this study gave a relatively stable performance against hourly change of the flow rate and showed a satisfactory removal efficiency of nitrogen and phosphorus compounds under experimental conditions. The average removal efficiency of total nitrogen gradually decreased as the influent total nitrogen concentration was increased. High C/N ratio of the wastewater was required for the complete removal of nitrogen. Glucose as a carbon source was more efficient than starch and the removal ability for all components become hither with the increase of the fraction of glucose.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.940-944
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• 2006

The propose of this study was to evaluate the microbiological hazards of the customers' hands in university foodservice operation. A total of 190 customers' hands were sampled to test about aerobie plate counts, coliforms, E. coli and Staphylococcus aureus. The average number of aerobic plate counts was 3.11 log CFU/hand Ifrom 0.70 to 6.47 log CFU/hand) and that of coliform counts was 1.06 log CFU/hand (from not detected to 5.04 log CFU/hand). The mean level of aerobic plate counts (t=9.87, p<0.001) and coliforms (t=7.91, p<0.05) was significantly different by gender. E. coli was not detected, but Staphylococcus aureus was detected in 39 (20.5%) of 190 samples. The average of hand-washing frequency was 6.46 time per day. By the hand-washing frequency, the mean level of aerobic plate counts was significantly different (F=527, p<0.001), but coliforms was not significantly different. This study shows that it is needs to be given attention to hygiene handlers but also for customers in foodservice operations.