Nano carbon tubes make efficient solar panels

Nanotubes8212;carbon cylinders 100,000 times thinner than a human hair8212;may turn out to make efficient solar panels.

Nanotubes8212;carbon cylinders 100,000 times thinner than a human hair8212;may turn out to make efficient solar panels. Georgia Tech scientist Jud Ready made a grid of millions of nanotubes and coated them with a light-absorbing semiconductor material. When sunlight shines on the grid, each tiny nanotube 8220;tower8221; converts the light to electricity, just like in a conventional solar panel. However, the nanotubes get an energy bonus because light ricochets from one tower to the next, increasing the amount of light that gets absorbed. Ready8217;s solar cells also have the advantage of being compact and lightweight, which may make them suitable for use in weather satellites or space stations, where size and weight are critical. To gain wider use, however, somebody will have to figure out a way to manufacture them more cheaply. Currently the nanotube grids entail tricky chemistry in a 700-degree Celsius furnace.

No danger for bacteria from 8220;buckyballs8221;

Bacteria appear not to be harmed when the soil they live in becomes contaminated with 8220;buckyballs8221;8212;microscopic spheres of carbon that are being manufactured in increasing quantities for a variety of applications. Buckyballs are a kind of nanoparticle: atomic-scale constructs with novel properties that make them useful in electronic devices, fabrics, cosmetics and other products. Earlier studies had shown they can kill soil bacteria in laboratory dishes, raising concerns that their release could upset soil ecosystems. Now researchers at Purdue University have performed the first tests of buckyball toxicity on bacteria in actual soil. Using a variety of measures of microbial health8212;including bacterial respiration, enzyme activity and various chemical analyses8212;they showed that buckyball concentrations of up to 1,000 micrograms per gram of soil had no discernible impact. It may be that natural chemicals in soil buffer the toxic effects seen in the laboratory, researchers conclude in the April 15 issue of the journal Environmental Science 038; Technology.

Explosives-sniffing tech creator wins Lemelson-MIT award

A scientist who created bomb-sniffing technology to help clear land mines won the Lemelson-MIT Prize last Monday, a decade after he began developing it under a Pentagon-funded research project. Today, US soldiers in Iraq are using Timothy Swager8217;s handheld device to scan people and automobiles for traces of bomb-making materials or for hidden explosives that can be detected through telltale chemical vapours. Swager worked with colleagues to invent synthetic material that attracts chemicals like TNT typically used in explosives. The invention is capable of detecting minute traces of explosives at chemical concentrations as low as a few parts per trillion.LAT-WP, Newsweek, AP