Leland Stanford Junior University

Vineeth Chandran Suja

Gerald G Fuller

Suzanne G K Calhoun

Miscible antifoams are provided that do not separate out of a target liquid and that are easy to incorporate in the target liquid. A method or system involves mixing a liquid ('a miscible antifoam') into a target foaming liquid. This miscible antifoam is engineered/chosen such that it has both a higher surface tension and is more volatile than the target liquid, or engineered such that it has both a lower surface tension and is less volatility than the target liquid. The miscible antifoam leads to surface tension gradients that cause bubble rupture up to 10 times faster than the target liquid without the antifoam. Further, the miscible antifoams are easy to incorporate and do not separate out from the target liquid during operation—both of which are key limitations faced by existing antifoams.

Fully miscible antifoam formulations

Dynamic thin film interferometry is a technique used to non-invasively characterize the thickness of thin liquid films that are evolving in both space and time. Recovering the underlying thickness from the captured interferograms, unconditionally and automatically is still an open problem. A compact setup is provided employing a snapshot hyperspectral camera and the related algorithms for the automated determination of thickness profiles of dynamic thin liquid films. The technique is shown to recover film thickness profiles to within 100 nm of accuracy as compared to those profiles reconstructed through the manual color matching process. Characteristics and advantages of hyperspectral interferometry are discussed including the increased robustness against imaging noise as well as the ability to perform thickness reconstruction without considering the absolute light intensity information.

Growing community of inventors

Stanford, CA, United States of America

Vineeth Chandran Suja