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- 积分
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- 17983
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- 26159
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2013年11月21日 Nature
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$ H1 w. ~2 g. i, v j2 u: N9 kA water drop strikes the water-averse wing of a Morpho ! C5 S R3 I/ h1 J0 u4 D O
butterfly. There are many uses for surfaces that can stay dry, self-clean or ) O' ^7 x0 b8 O$ F; d
resist icing. Liquid drops hitting such surfaces tend to spread out and then & d. G# s1 I6 h6 `. Y" }
retract before finally bouncing. Many applications benefit from minimizing the
+ {, u- s2 R) F6 e* h8 i0 ?' l% S6 rcontact time between drop and surface, which is generally assumed to occur if
/ G+ s0 `6 F5 a! S7 Jthe impacting drop deforms symmetrically. Kripa K. Varanasi and colleagues now
9 v% a2 x# { \- Hshow that drops bounce off faster from a superhydrophobic surface with a $ A' V7 } }4 x. d2 A
morphology that redistributes the liquid mass so that it no longer spreads and # d/ J0 I3 H2 |4 C* `
retracts symmetrically. Theory and experiments confirm that this strategy
2 l2 }! c6 o- W# Xshortens the contact time between a bouncing drop and a surface beyond what was $ ~4 E8 ?8 ^4 V
thought possible. Photo: A. T. Paxson, K. Hounsell, J. W. Bales, J. C. Bird
+ [- k" G8 @ {) h+ f& K. Varanasi.
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发表于 2013-11-22 18:25
发表于 2013-11-23 19:31
