SSS 2008-02-04
时间:2019-01-08 作者:英语课 分类:Scientific American(二)月
This is Scientific Americans' 60-Second Science. I'm Chelsea Wald. Got a minute?
Vinaigrette dressing 1: when you shake it little vinegar droplets 3 scatter 4 through the oil, but when you put it down, the droplets merge 5 and the dressing separates. That's probably not a big inconvenience to you, but it is to industries that use lots of vinaigrette-like mixtures. So to study this unmixing, French researchers planned to float water droplets one at a time through a channel of flowing oil. The channel widened in the middle so the oil would slow down and bump the water droplets together. Then the passage narrowed again so the oil would speed up and pull the droplets apart. The researchers expected that the droplets would merge when they bumped together. But that's not what happened. In fact it was when the droplets started to pull apart from each other that they suddenly mixed. In Physical Review Letters, the researchers say that the pulling apart may make the pressure between the droplets fall. That would make the droplets burst open and then they could merge into one big water droplet 2. What the researchers don't say is whether this finding could lead to a true breakthrough: stay-mixed salad dressing.
Thanks for the minute for Scientific Americans' 60-Second Science. I'm Chelsea Wald.
- Don't spend such a lot of time in dressing yourself.别花那么多时间来打扮自己。
- The children enjoy dressing up in mother's old clothes.孩子们喜欢穿上妈妈旧时的衣服玩。
- The rate of droplet growth under different conditions can be evaluated.可以计算在不同条件下的云滴增长率。
- The test results showed that increasing droplet size was associated with better stability.试验结果表明,增加液滴尺寸将使稳定性提高。
- Droplets of sweat were welling up on his forehead. 他额头上冒出了滴滴汗珠。 来自辞典例句
- In constrast, exhaled smoke contains relatively large water droplets and appears white. 相反,从人嘴里呼出的烟则包含相当大的水滴,所以呈白色。 来自辞典例句
- You pile everything up and scatter things around.你把东西乱堆乱放。
- Small villages scatter at the foot of the mountain.村庄零零落落地散布在山脚下。