• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.3
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• pp.287-292
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• 2004

An experimental investigation was carried out to study the performance of a bubble pump for the diffusion absorption refrigerating system. Ammonia was used as the refrigerant and the helium was charged in order to balance the pressure between the low and high pressure side. As experimental variables, the concentration of ammonia charged into system, heat input, and the pressure of helium were selected. Experimental results show that the generation rate of ammonia vapor and the circulation rate of diluted ammonia solution were increased as the heat input increases, but the ratio of the solution to vapor flow rate was decreased. The generation rate of refrigerant vapor and the circulation rate of diluted ammonia solution increased as the system pressure decreased. Finally under the condition of 25 bars, the concentration of rich ammonia solution was not affected by the generation rate of ammonia vapor and the circulation of diluted ammonia solution.

• The Korean Journal of Pesticide Science
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• v.8 no.2
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• pp.112-116
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• 2004

Two experiments were carried out in greenhouse under hydrophilic culture facilities and simulation model to provide residual characteristics of ethoprophos treated in sweet pepper's growth. To identify the pattern of absorption-translocation through the plant roots, ethoph 5 % GR were diluted in hydrophilic culture solution and drenched at a time per day for three days. The residue in fruit came closed to 0.02 ppm of MRL at 10 days after treatment(DAT) and reached peaked 0.06 ppm at 30 DAT and remained excess MRL level until around 40 DAT. To confirm the pattern of contamination by volatilization of ethoprophos, ethoph 5%GR was scattered 2 g per cubic meter. At 72 hours after treatment, the residue in sweet pepper fruit was exceed the MRL and the maximum residual amount were 0.62 ppm by volatilization. Consequently the use of ethoprophos during the growth of sweet pepper would be strong possibility to exceed the MRL.