Wednesday 24 December 2014

Video Recording at Hundred Billion frames per second

I work in TV and Video media. And record at 25 frames per second. Enough to fool the eye into thinking it is continuous. Even with 11 frames one can create a sense of continuity.
But when we want to observe transient events of smaller time scales, something that happens in much less than 1/25th of a second, my cameras are not much of use.
In early 21st century, a Japanese scientist claimed to reach a speed of 10 million frames per second, with CMOS technology. Not bad.
But now there is a report on recording of a hundred billion frames per second. The new technology will expose physical, chemical and biological phenomena that are not amenable to perception by our neuronal mechanisms. Since fluorescent and luminescent objects are captured by the camera, many researchers will want to use it. Take a look at the description in a recent paper. Nature 516, 74–77 (04 December 2014). Now we can see a video of a laser pulse moving in air and resin at -  http://www.nature.com/nature/journal/v516/n7529/fig_tab/nature14005_SV4.html

Liquid inclusions make soft solids stiffer

When you include liquid drops into a soft solid like a gel, the anticipation is that it will become softer. But if you keep reducing the radius of the drops, then there comes a time when it will actually become stiffer.
This rather counter-intuitive result was published a recent paper in Nature Physics (Published online on 15 December 2014) by collaborating scientists from three countries. The phenomenon occurs only when the radius of the droplets become smaller than the elastocapillary length (the ratio of surface tension of the liquid solid interface and the young's modulus of the solid).
Besides designing new composites, the result has implications in biology where such phenomena may be rampant, without being noticed by biologists.