Archive for June 15th, 2010

Before You Add the Flash

On properly heating your pan

How to keep food from sticking in a stainless-steel pan. The first explanation about pores biting into the food sounds hokey, but then we get to the Liedenfrost effect, which is demonstrated in the video.

The water “hovering” over the stainless steel pan like mercury happens due to the phenomenon known as the Leidenfrost effect. You can read more about it on wikipedia, but the basic idea is this: at a certain temperature known as the Leidenfrost point (roughly around 320˚F for water, but varying with surface and pressure), when the water droplet hits the hot pan, the bottom part of the water vaporizes immediately on contact. The resulting gas actually suspends the water above it and creates a pocket of water vapor that slows further heat transfer between the pan and the water. Thus it evaporates more slowly than it would at lower temperatures. At the proper temperature, a similar effect happens with the food you place in the pan, preventing the food from sticking.

Potato Chips vs Clean Energy Technology

Gates, venture capitalist Doerr issue warning about America’s future

Of the top 30 new energy technology companies worldwide that produce batteries, solar technologies and advanced wind energy, only four are headquartered in the United States, Doerr said.

“It’s very sad that Americans spend more on potato chips than we do on investment in clean energy R&D,” said Doerr.

Gates said more federal research spending is needed to spur investment in clean technologies. “The incentives aren’t there to make it happen,” said Gates.