Summary: Journal of Colloid and Interface Science 247, 255­257 (2002)
doi:10.1006/jcis.2001.8165, available online at http://www.idealibrary.com on
LETTER TO THE EDITOR
Effective Spring Description of a Bubble or a Droplet
Interacting with a Particle
It is shown that the interaction of a particle with a liquid drop
or a gas bubble may be quantitatively described over the whole
distance regime by treating the fluid interface as a Hookean spring.
An algorithm suitable for analyzing atomic force microscopy data
suitable for a calculator or a spread-sheet is given and applied to
data for oil drops. C 2002 Elsevier Science (USA)
Key Words: bubble; droplet; particle interaction; atomic force
microscopy.
INTRODUCTION
Colloid probe force measurements with the atomic force microscope (AFM)
have shown that air bubbles (1­4) and oil droplets (5­9) behave as simple
Hookean springs in the so-called constant compliance regime. A recent the-
oretical analysis has confirmed this experimental finding, showing that the ex-
perimentallyappliedloadsarewellwithinthelinearregime,andthattheeffective
spring constant is practically equal to the surface tension of the interface (10).

Source: Attard, Phil - School of Chemistry, University of Sydney

Collections: Chemistry