Obama and McCain, huh? Glad that’s over with. I was starting to think we might be better off if the entire city of DC just slid into the Potomac. But now that it’s over, I’m sure the TV pundits, newspaper editorialists, and bloggers will be back to discussing the latest progress in experimental physics any minute now.
No? Well, I guess we’ll have to do it ourselves. Here’s something interesting from the most recent issue of Science.
Trapped air bubbles influence the taste, smell, and feel of foods and cosmetics, but keeping air bubbles stable within a liquid for long periods of time can be tricky. When the bubbles get to be micrometers in size, they rapidly expand at the expense of smaller bubbles. Dressaire et al. (p. 1198) show that using a mixture of mono- and di-ester surfactants can stabilize bubbles for more than a year. The surfactants assemble on the surface of the bubbles in a hexagonal pattern, and it is this packing that leads to the long-term stability.
That’s the summary of this article, bearing the imposing name (given that it’s about bubbles!) “Interfacial Polygonal Nanopatterning of Stable Microbubbles”.
In short, all kinds of things from whipped cream to soap depend on little microscopic bubbles being kept in suspension within the material. But just as big bubbles tend to join to form bigger bubbles, microscopic bubbles tend to form bigger microscopic bubbles. Depending on what you’re trying to do, this can be a very bad thing. But these scientists have successfully studied some of the details of what causes these bubbles to join, and found a way to slow the process down to time scales on the order of a year. Whip up a a hexagonal lattice to cover each bubble - well, adjust the chemistry involved so that the lattice pack s itself - and the bubbles stay put for a long time. The boundaries are nice and elastic and resist collapse. It’s obviously considerably more complicated to understand and put into practice or it wouldn’t be worth publishing in Science, but it’s yet another fantastic demonstration on how cutting-edge science can appear in the most mundane of phenomena.
Still not as dramatic as a bitter nomination fight, but much more useful.
1 response so far ↓
1 Carl Brannen // Jun 4, 2008 at 3:48 pm
Earlier this year I ended up in the emergency room for a gall bladder removal. During the 24 hours there, I got lots of needles inserted in me.
The nurses leave bubbles in the lines. I got to thinking, what is going to happen to these? How come they don’t damage the body? What happens to them? It’s a good physics problem and I’ll leave it to the readers to enjoy the contemplation (and hope that they don’t have the pain to go with it).
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