מכל מלמדײ השכלתי (duchifat) wrote,
מכל מלמדײ השכלתי
duchifat

Британские ученые популяризаторы совсем... пишут. Кстати, в сети я этой статьи не вижу. :)

Jessica Griggs, "Stain relief" New Scientist on 24 November 2012, p 46-49

"The lotus leaf was dubbed superhydrophobic, defined as a material that produces a contact angle greater than 150 degrees, or requires a 5 degree tilt or less to get droplets to roll off. “It led to an explosion of studies,” says Michael Nosonovsky, a mechanical engineer at the University of Wisconsin-Milwaukee.
....

But if water is over-friendly as a liquid, oil is positively dissolute. Its molecules tend to be only weakly attracted to each other, so it doesn’t take a large adhesive force to overcome a droplet’s cohesion when it hits a surface. Rather than bead up and fall off, it spreads out and seeps in – as many a soiled party dress can testify. Overcoming this behaviour required a finer-grained approach. In 2007, Nosonovsky showed that if you got the architecture of a surface’s roughness just right, creating caves, nooks and crannies that bend back in on themselves, you could create repulsive surface forces equating to huge contact angles for all sorts of liquids (Langmuir, vol 23, p 3157). It was a simple but game-changing insight.

....

Nosonovsky agrees that such applications have great potential, but points out that there are still a few sticking points before they become reality. For a start, they would require the surface to constantly replace its lubricant, because every droplet rolling off the surface takes a portion of the surface with it."
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  • dybr

    В Питере нарастает волна эпидемии, я очень боюсь, что, танцы закроют. Тут провакцинировано только 10% населения (а для стадного иммунитета надо 50%),…

  • (no subject)

    Много говорят о версии утечки вируса из Уханского институте вирусологии. При этом никаких новых данных в пользу этой версии нет. Эта версия…

  • (no subject)

    Бачата в Парке Победы вчера

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