[International Market Watch/Business Magazine( A Cm_a Venture)] 1/17/2007 05:00:00 AM

[International Market Watch/Business Magazine]

Scince & Business

By: Tatiana McGarry

Editor: Toni Kelley

Physicists Jingquan Wei, of Tsinghua University in China, and Bingquig Wei, of Louisiana State University, is currently experimenting with prototypes for a new kind of light bulb. In these prototypes, called SWNT (single-walled nano-tube) bulbs, the tungsten filament of a conventional incandescent light bulb is replaced by a filament made of carbon nano-tubes.
Carbon nano-tubes are microscopic cylinders of carbon which have several remarkable properties. They are extremely efficient conductors of energy, as well as being extraordinarily strong.
In conventional light bulbs, the thickness of the tungsten generally varies across the length of the filament, resulting in "hot spots" which are prone to breakage. When the filament breaks, the light bulb burns out. Because of the cylindrical shape of the carbon nano-tubes, filaments crafted from this material are much more uniform in thickness. This suggests that nano-tubes could be used to develop a light bulb that would last almost indefinitely.
In addition, because carbon nano-tubes efficiently conduct energy, SWNT bulbs emit more light per volt than their tungsten-filament counterparts. Therefore, a SWNT bulb uses less energy than a conventional light bulb of the same illumination.
Though more work needs to be done to perfect their design, scientists estimate that nano-tube light bulbs could be available to the public within a few years.

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Posted by International Market Watch/Business Magazine to International Market Watch/Business Magazine( A Cm_a Venture) at 1/17/2007 05:00:00 AM