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arXiv · 1705.02873

Hydrodynamic signatures of stationary Marangoni-driven surfactant transport

S. Mandre·V. S. Akella·D. K. Singh·R. S. Singh·M. M. Bandi
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Abstract

We experimentally study steady Marangoni-driven surfactant transport on the interface of a deep water layer. Using hydrodynamic measurements, and without using any knowledge of the surfactant physico-chemical properties, we show that sodium dodecyl sulphate and Tergitol 15-S-9 introduced in low concentrations result in a flow driven by adsorbed surfactant. At higher surfactant concentration, the flow is dominated by the dissolved surfactant. Using Camphoric acid, whose properties are {\it a priori} unknown, we demonstrate this method's efficacy by showing its spreading is adsorption dominated.

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S. Mandre, V. S. Akella, D. K. Singh, R. S. Singh, M. M. Bandi. 2017-05-08. Hydrodynamic signatures of stationary Marangoni-driven surfactant transport. https://doi.org/10.1103/physrevlett.119.264501

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