ChemWeb Newsletter

Not a subscriber? Join now.March 27, 2007

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This week's award goes to Perry McCarty for his pioneering work in understanding waste water chemistry and microbiology. The Alchemist this week discovers how a bodybuilders' supplement might help treat Parkinson's disease, the route taken by mercury from groundwater to coast, and how to boost your storage space with fullerenes. Also this week, physical condensation problems solved and how Raman is laying it on thin to help scientists understand carbon sheets.




Scientists have leaped into a quantum state and taken their first close look at the exotic form of matter that exists in a Bose-Einstein condensate (BEC). Michael Kühl and colleagues at the Swiss Federal Institute of Technology (ETH) in Zurich and the University of Cambridge, UK, magnetically confined a BEC of rubidium atoms and warmed it so that it would cross the critical condensation temperature, but in reverse. By varying conditions as the BEC transitions into a normal gas above its critical temperature the team was able to estimate the size of the BEC bubbles within which all atoms are in the same quantum state. Their approach could prove very fruitful in investigating these intriguing materials.





Graphene is a big molecule, essentially a single graphitic layer it extends to infinity in the plane, at least as far as any individual carbon atom perceives it. Sheets of graphene hit the news headlines when researchers discovered they could carve out an almost atomic scale transistor from this material hinting at an "ex" silico world for future computers. While there is a long way to go before Silicon is anything but "in", chemists are now using Raman spectroscopy to probe the details of this unique material and related structures such as fullerenes. The researchers discuss an empirical formula for the in- and out-of-plane crystalline size and even "fancier" Raman-based information. The insights this powerful but not so well-known technique can provide for the atomic structure at graphite edges and graphene layers could accelerate the technological development of such materials.





Could a gaseous giant be strong enough to pressurize water into a metallic state? That's the suggestion of a new theoretical study of water crystallites that could form under marginally less extreme conditions of temperature and pressure than previously thought. On the ice giant planet Neptune and the gas giant Jupiter, temperatures of 4000 K and pressures of 100 gigapascals might exist, which the new study by Thomas Mattsson of Sandia National Laboratory suggests are enough to push water into a metallic, cubic ice phase. In this phase, the oxygen atoms are locked in place, but the hydrogens are more freely mobile providing a medium for electrical conduction.





Almost 2000 Parkinson's disease patients are to be recruited into a study to test the effects of the bodybuilders' dietary supplement, creatine. Bodybuilders and athletes use creatine to help boost their energy levels and to build muscle. The compound has already demonstrated some efficacy in Lou Gehrig's disease and muscular dystrophy and Kapil Sethi, of the Medical College of Georgia wants to investigate whether it might give a boost to dying brain cells in Parkinson's disease too. "We think it may help cells that are damaged or overworked," explains Sethi.





Matt Charette and colleagues at Woods Hole Oceanographic Institution (WHOI) have discovered a significant pollution route for total mercury flowing from groundwater into coastal waters. Mercury is most toxic as methyl mercury rather than its elemental form and the next step will be to quantify the impact of total mercury in the marine environment. Mercury pollution originates from industrial emissions, which ultimately precipitate as rain or snow on to land or directly into the oceans. Inland deposits of mercury are also weathered and carried to the coast in runoff from streams and rivers, where they accumulate in the sediments that build up along the shoreline. "This pathway for delivering nutrients and contaminants into the ocean has long been overlooked and ignored because it was difficult to quantify," explains Charette, "This study is a first of its kind for quantifying the amount of mercury flowing out of the system."





The search for new materials that can store hydrogen safely for fuel cell applications is ongoing. Researchers at the Institute of Applied Mechanics, of the Ural Branch of the Russian Academy of Sciences, reckon one class of materials has until now been overlooked in this endeavor - the fullerenes. The team has now used molecular dynamics methods to analyze hydrogen absorption by C20, C60, C80, C180, C240, C540 fullerenes and the C46, C167, C505 carbonic clusters at various pressures and temperatures. Their results revealed the optimal thermodynamic parameters for using the hollow carbon cages as hydrogen storage capsules. Hydrogen can be absorbed to almost 14% capacity at 60 K and 10 MPa, the team says, in the fullerene-like carbonic clusters.