• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권4호
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• pp.241-247
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• 2000

This paper reports on an experimental study of the absorption of COS in a secondary amine diethanolamine. The primary objectives were to investigate an analogy between $N_2$O and COS, thereby allowing an estimation of the physical solubility and diffusivity of the sulfur gases in the reacting amine solutions. The solubilities and diffusivities of $N_2$O and COS in 5~25% aqueous polyethylene glycol at $25^{\circ}C$ were measured. The results appeared to verify the use of an $N_2$O-COS analogy for estimating the solubility and diffusivity of COS in aqueous solutions of alkanolamines up to an approximate 25 weight % concentration. The mean deviation of the $N_2$O analogy relative to the measured solubilities was 3.7%, and the mean deviation between the analogy and the measured diffusion coefficients using the experimental values for Hcos/PEG was 14.6%.

• 한국환경과학회지
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• 제12권5호
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• pp.551-557
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• 2003

An experimental study of the absorption of CS$_{2}$ in the secondary amine diethanolamine(DEA) was performed in this work. The primary objectives were to investigate an analogy between N2O and CS$_{2}$ permitting estimation of the physical solubility and diffusivity of the sulfur gases in the reacting amino solutions. The solubilities of CS$_{2}$ in water at 25, 40 and 6$0^{\circ}C$ has been measured. The data show fair agreement with previous literature values. The solubility of CS$_{2}$ in 5-25 weight % polyethylene glycol has been measured in order to investigate a possible analogy between CS$_{2}$ and N$_{2}$O The diffusivities of CS$_{2}$ in water and the reaction rate between CS$_{2}$ and DEA has been measured at 25 and 4$0^{\circ}C$, using a wetted sphere apparatus operated at approximately 1/3 atmospheres pressure, which is a previously untried method.

• 한국과학교육학회지
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• 제15권1호
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• pp.17-26
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• 1995

The purposes of this study were to investigate the effects of systematic analogy on pupils' concepts changes compared with non-systematic analogy and no analogy using longuitudal study. The subjects were the second year middle school students(N=140), 49 of them were experimental group, using systematic analogy; 47 of them were control group 1, using non-systematic analogy; and 44 of them were control group 2, using no analogy. We have elicited their ideas about electric current three times: pretest, posttest and delayed posttest by P-O-E(Prediction-Observation-Explanation) method. With time, resistant ;rrelevant idea was decreasing dominantly; sequential reasoning idea and scientific idea were increasing; and current consumption idea was rare. Systematic analogy is more effective than non-systematic analogy on pupils' concepts changes of electric current. Systematic analogy is more effective than no analogy in case of simple situation, but we couldn't find significant difference between systematic analogy and no analogy in case of complicated situation.