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Updated: Aug 20, 2026

Extraction and Characterization of Surfactants from Atmospheric Aerosols
Published on: April 21, 2017
Measurement of the long- and short-range hydrophobic attraction between surfactant-coated surfaces
Qi Lin1, Emily E Meyer, Maria Tadmor
1Department of Chemical Engineering, University of California at Santa Barbara, CA 93106, USA.
Abstract:
We have measured the attractive long-range 'hydrophobic' forces in water between double-chained surfactant monolayers physisorbed on mica. We used both normal and high-speed video cameras to follow the dynamics and possible rate-dependence of force-distance profiles in the distance regime from 1000 A to adhesive contact, including the short-distance regime below 100 A-the regime of greatest biological interest. We find that the hydrophobic interaction follows a double-exponential function down to separations of approximately 50 A, after which point the attractive force appears to become considerably stronger.
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