Top Sciences Free Pdf
First Bose-Einstein condensation of strontium
Posted by wideant in Quantum Physics on March 19, 2010
In an international first, scientists from the Institute of Quantum Optics and Quantum Information (IQOQI, Austria) produced a Bose-Einstein condensate of the alkaline-earth element strontium, thus narrowly winning an international competition between many first-rate scientific groups. Choosing the isotope 84Sr, which has received little attention so far, proved to be the right choice for the breakthrough. It can now be regarded as an ideal candidate for future experiments with atomic two-electron systems.
This is not the first time that Prof. Rudolf Grimm and his scientific team have won a tightly contested race between scientists: in 2002, they were the first to produce a Bose-Einstein condensate of cesium atoms. Read the rest of this entry »
Researchers Identify Key Molecules in Photosynthesis
Posted by wideant in Biochemistry on March 13, 2010
Chemistry professor Harry Frank led an international group of researchers that identified the molecules in algae which direct the organisms to convert sunlight into oxygen. The findings may ultimately help in developing new solar energy conversion devices.
Chemists in the College of Liberal Arts and Sciences have identified the molecules in algae that direct the organisms to convert light from the sun to oxygen in the process known as photosynthesis.
Their research, published online in the Proceedings of the National Academy of Sciences (PNAS), reveals for the first time the most important molecules involved in controlling the energy flow in photosynthesis in a system as complex as marine algae. Read the rest of this entry »
LED streetlights best buy for cities, researchers report
University of Pittsburgh researchers have conducted the first cradle-to-grave assessment of light-emitting diode (LED) streetlights and determined that the increasingly popular lamps strike the best balance between brightness, affordability, and energy and environmental conservation when their life span—from production to disposal—is considered. LEDs consist of clusters of tiny, high-intensity bulbs and are extolled for their power efficiency and clear luminosity.
Engineers in the Mascaro Center for Sustainable Innovation based in Pitt’s Swanson School of Engineering compared LED streetlights to the country’s two most common lamps—the high-pressure sodium (HPS) lamps found in most cities and metal halide lamps akin to those in stadiums—and the gas-based induction bulb, another emerging technology billed as bright and energy efficient. The team reported that LEDs may carry a formidable price tag, but in comparison to HPS and metal halide lamps consume half the electricity, last up to five times longer, and produce more light. Induction lights proved slightly more affordable and energy efficient than LEDs, but may also have a greater environmental impact when in use. The authors also noted that LED technology exhibits more potential for improvement and may surpass induction lamps in the future. Read the rest of this entry »