Dataset Information

Enhancing droplet deposition through in-situ precipitation.

ABSTRACT: Retention of agricultural sprays on plant surfaces is an important challenge. Bouncing of sprayed pesticide droplets from leaves is a major source of soil and groundwater pollution and pesticide overuse. Here we report a method to increase droplet deposition through in-situ formation of hydrophilic surface defects that can arrest droplets during impact. Defects are created by simultaneously spraying oppositely charged polyelectrolytes that induce surface precipitation when two droplets come into contact. Using high-speed imaging, we study the coupled dynamics of drop impact and surface precipitate formation. We develop a physical model to estimate the energy dissipation by the defects and predict the transition from bouncing to sticking. We demonstrate macroscopic enhancements in spray retention and surface coverage for natural and synthetic non-wetting surfaces and provide insights into designing effective agricultural sprays.

SUBMITTER: Damak M

PROVIDER: S-EPMC5013560 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Enhancing droplet deposition through in-situ precipitation.

Damak Maher M Hyder Md Nasim MN Varanasi Kripa K KK

Nature communications 20160830

Retention of agricultural sprays on plant surfaces is an important challenge. Bouncing of sprayed pesticide droplets from leaves is a major source of soil and groundwater pollution and pesticide overuse. Here we report a method to increase droplet deposition through in-situ formation of hydrophilic surface defects that can arrest droplets during impact. Defects are created by simultaneously spraying oppositely charged polyelectrolytes that induce surface precipitation when two droplets come into ...[more]

PMID: 27572948

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Dataset Information

Enhancing droplet deposition through in-situ precipitation.

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Enhancing droplet deposition through in-situ precipitation.

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