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【答案】应助回帖
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刘亚君880530: 金币+25, 翻译EPI+1, ★有帮助, 你可能不是很了解我的专业知识，但是你很用心，谢谢了！ 2012-12-21 09:18:34
(I'm not familiar with your background, and the translation of many technical terms are found from this thesis: https://personalpages.manchester ... _fractionation.pdf)
To keep the foam fractionation column (FFC) continuously producing foam at a steady state, it is necessary to maintain the flow rate of foam, the liquid hold-up, and the degree of absorption (of surfactants? 指的是表面活性剂的吸附么？) at the air-water interface all at constant levels. The flow rate of foam equals the sum of the flow rate of gas, q, and the flow rate of liquid carried by the foam, p (这里少了一个变量名？), as shown in equation (4).
.............................................................................(4)
The liquid hold-up of the foam is calculated by equation (5).
.............................................................................(5)
The bulk solution was added into the FFC using a peristaltic pump at a constant flow rate, and when the liquid level in the pool (不知液池的专业术语是什么，暂译作pool, 下同) was steady, it indicated that the flow rate of feeding stream equals the flow rate of the liquid carried up in the foam out of the top of the column, as shown in equation (6).
..............................................................................(6)
Therefore, the feeding flow rate of the peristaltic pump can be calculated by the known foam flow rate and the liquid hold-up, using equation (5).
To maintain the degree of surfactant absorption at air-water interface at a steady value, the SDS concentration in the pool must be kept constant, hence the liquid at the bottom of the column was sampled every 5 minutes during the experiments, until no difference in the SDS concentration was observed. When the foam formation in the FFC was stable, the foams were gathered in a foam collecting apparatus for the study of bubble collapse. The sieve plate (perforated plate) were added into the foam collecting apparatus from the bottom to top, and the number of plates were increased for each run. The foam collecting apparatus was rinsed with bulk solution before each run to avoid the effect of wall wettability. The time of filling the foam collecting appratus was recorded, and the bubble collapsing rate R is calculated by equation (7):
...............................................................................(7)
where V_r (这里少了一个变量名？) is the volume of the remaining foam, V_t (这里少了一个变量名？) is the total volume of the foam entered the collecting apparatus, and t is the time of filling the whole apparatus with foam. For each condition, the experiments were repeated three times and the average results were reported. All experiments were performed at room temperature, and the ambient humidity was ... |
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