聚二甲基硅氧烷水膜对3种蚊虫的实验室控制效果研究

目的评价和比较实验室条件下聚二甲基硅氧烷水膜对致倦库蚊、白纹伊蚊、埃及伊蚊不同龄期幼虫和蛹的防治效果。方法挑选不同龄期的幼虫和蛹各30只,分别置于1 ml/m^(2)水膜的水体中,在实验室环境或人工培养箱设置的不同温度下观察幼虫或蛹的生长、发育及死亡情况,通过Excel 2016和SPSS 27.0软件进行数据的整理和分析,通过log-rank检验比较各组幼虫或蛹接触水膜后的生存曲线,采用独立样本t检验比较不同组的幼虫长度。结果在1 ml/m^(2)的水膜作用下,致倦库蚊、白纹伊蚊和埃及伊蚊Ⅰ~Ⅱ龄幼虫的半数致死时间分别为2.67、7.04和6.45 d,Ⅲ~Ⅳ龄幼虫分别为0.53、1.64和1.71 d,蛹分别为96.68、115.54和109.77 min;饲养7 d后,致倦库蚊、白纹伊蚊和埃及伊蚊水膜组平均虫体长度分别为(3.28±0.40)、(3.17±0.61)和(3.21±0.47)mm,明显小于相应的对照组(均P<0.001);在20、25、30和35℃下水膜组幼虫的死亡率随温度的升高而升高,致倦库蚊第1天的死亡率分别为66.67%、71.11%、91.11%和100%,白纹伊蚊分别为8.89%、30.00%、55.56%和81.11%,埃及伊蚊分别为14.44%、25.56%、56.67%和75.56%。结论聚二甲基硅氧烷水膜对3种蚊幼虫及蛹均有较好的控制效果,可抑制幼蚊的生长发育,同时环境温度的升高对水膜的功效有促进作用,适合于多种蚊虫的防控。

Pervaporation Separation of Butanol-Water Mixtures Using Polydimethylsiloxane/Ceramic Composite Membrane

Pervaporation has attracted considerable interest owing to its potential application in recovering biobutanol from biomass acetone-butanol-ethanol (ABE) fermentation broth. In this study, butanol was recovered from its aqueous solution using a polydimethylsiloxane (PDMS)/ceramic composite pervaporation membrane. The effects of operating temperature, feed concentration, feed flow rate and operating time on the membrane pervaporation performance were investigated. It was found that with the increase of temperature or butanol concentration in the feed, the total flux through the membrane increased while the separation factor decreased slightly. As the feed flow rate increased, the total flux increased gradually while the separation factor changed little. At 40°C and 1% (by mass) butanol in the feed, the total flux and separation factor of the membrane reached 457.4 g·m?2·h?1 and 26.1, respectively. The membrane with high flux is suitable for recovering butanol from ABE fermentation broth.