Yahoo News
A computer monitor shows seismic activity at the California Institute of Technology (CalTech) Tuesday, July 29, 2008, in Pasadena, Calif. A strong earthquake shook Southern California causing buildings to sway and triggering some precautionary evacuations. The jolt was felt from Los Angeles to San Diego, and slightly in Las Vegas.
No tags for this post.Strong quake shakes Southern California
By ROBERT JABLON, Associated Press Writer
LOS ANGELES – A strong earthquake shook Southern California on Tuesday, causing buildings to sway and triggering some precautionary evacuations. No immediate damage was reported.
The jolt was felt from Los Angeles to San Diego, and slightly in Las Vegas.
Preliminary information from the U.S. Geological Survey estimated the quake at magnitude 5.8, centered 29 miles east-southeast of downtown Los Angeles near Chino Hills in San Bernardino County.
Los Angeles Fire Department spokesman Brian Humphrey said there were no immediate reports of damage or injury in Los Angeles. San Bernardino County fire dispatch also had no immediate reports of damage.
The quake struck at 11:42 a.m. PDT. Buildings swayed in downtown Los Angeles for several seconds.
Workers quickly evacuated some office buildings.
“It was dramatic. The whole building moved and it lasted for a while,” said Los Angeles County sheriff’s spokesman Steve Whitmore, who was in the sheriff’s suburban Monterey Park headquarters east of Los Angeles.
No tags for this post.13:11 25 July 2008
NewScientist.com news service
Colin Barras
‘Fuel battery’ could take cars beyond petrol
A new approach to storing electrical energy can store more energy than gasoline in the same volume, and could help extend the range of electric vehicles. But some experts say other approaches are more practical.
The biggest technological hurdle facing electric vehicles is their range. Even the best rechargeable batteries cannot match the density of energy stored in a fuel tank.
Combining electric power with a combustion engine to make a hybrid electric vehicle sidesteps that problem. But a new take on electrical power storage that is part battery, part chemical fuel cell could ditch gasoline for good.
The new design stores energy more densely than petrol, and was conceived by Stuart Licht of the University of Massachusetts, Boston, and colleagues.
Batteries produce electricity from a closed chemical system that is eventually exhausted. Fuel cells use a constant supply of fuel, so they are continually topped up. Licht’s cell has features of each.
Its negative electrode, or anode, is made from vanadium boride, which serves double-duty as a fuel too. But unlike the flowing fuel of a fuel cell, the material is held internally, like the anode material of a battery.
The vanadium boride reacts with a constant stream of oxygen, as in a fuel cell, provided by the positive electrode, or cathode. This brings in a supply of air from outside.
The cell has a theoretical energy capacity of 27 kilowatt hours per litre, compared to 9.7 kilowatt hours per litre for gasoline. But both approaches are limited by practical factors to smaller figures.
Licht says his new system would likely have a practical energy capacity of around 5 kilowatt hours per litre. “But that’s two-fold higher than the practical storage capacity of gasoline,” he says.
He imagines drivers swapping exhausted vanadium boride electrodes for fresh ones at filling stations. The old electrode can be chemically regenerated for reuse. Consumers are more familiar with a mechanical process like that than with recharging a battery, Licht thinks.
Eric Stuve, a fuel cell specialist at the University of Washington, says Licht’s way of thinking makes sense, “especially the estimates of practical efficiencies”.
Chao-Yang Wang, a specialist in fuel cells and advanced battery technology at Pennsylvania State University, says the design is interesting, but adds that vanadium boride may take more energy to create than gasoline.
John Owen, an electrochemist at the University of Southampton, UK, thinks the results are less impressive than they seem.
He says that other designs could yield even higher energy densities than the vanadium boride system. A lithium-air cell should give twice the energy density of a vanadium boride-air cell. “Aluminium-air also gets close, and that is a well-established and large-scale technology,” says Owen. “Moreover, aluminium recovery is already done on a very large scale.”
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