Story tips from the Department of Energy's Oak Ridge National Laboratory: April 2011

H2O from diesel Capillary action and graphite foam are being enlisted by researchers at Oak Ridge National Laboratory to solve a logistical nightmare for the military and U.S. troops deployed around the world. While soldiers require nearly seven gallons of water a day, just getting that water to them increases troop vulnerability and limits their tactical use. Using an ORNL proprietary system, however, this problem could be greatly reduced. The system uses the pores of inorganic membranes to condense water present in a diesel's exhaust stream to produce about gallon of water from each gallon of diesel. The system also uses graphite foam, an R&D 100 Award-winning material developed at ORNL. Previously explored methods to produce potable water from diesel exhaust have been deemed "undeployable" by the military. [Contact: Ron Walli, (865) 576-0226; wallira@ornl.gov]

ELECTRONICS -- Plasmonic sensors

Plasmonic, or metallic, nanostructures are one step closer to fulfilling their promise as next-generation sensors and devices for high-speed communications because of research performed by scientists at Oak Ridge National Laboratory and Fudan University. Despite the potential, a big challenge has been to tune the optical response of plasmonic nanostructures in real time. By applying an external electric field and exploiting the unique electric and magnetic properties of a novel multiferroic substrate material, the researchers demonstrated the ability to achieve active control over the optical response of gold nanostructures with an unprecedented degree of tunability. "The unique optical response of metal nanostructures has catapulted the field of 'plasmonics' into the limelight with the promise of revolutionizing ways to deliver localized radiation for cancer research, optical circuitry for fast information transfer and ultra-sensitive biological and ultra-sensitive biological and chemical sensors," said Katyayani Seal of ORNL's Materials Science and Technology Division. The findings were published in Nano Letters (Vol. 11). [Contact: Ron Walli, (865) 576-0226; wallira@ornl.gov]

SENSORS -- Thwarting tax evaders

An estimated $1 billion in lost revenue each year is fueling an effort by Oak Ridge National Laboratory to prevent fuel tax evasions. The system being developed by a team led by Gary Capps will use evidential reasoning techniques, fuel markers, sensor and vehicle tracking devices to monitor, track and detect the movements of petroleum products. "We'll be able to determine the legitimacy of the movements and fuel loading and unloading, thereby enabling shippers and regulators to better keep track of the disposition of taxed and non-taxed petroleum-based products," Capps said. The system is being developed with assistance from Pilot Oil, based in Knoxville, Tenn. Money collected through the federal fuel tax funds the Highway Trust Fund, which is in turn apportioned to states for highway projects. [Contact: Ron Walli, (865) 576-0226; wallira@ornl.gov]

CLIMATE -- Extreme cold still in forecast

Despite an overall warming trend, extreme cold events are still likely to persist for the next century, according to research published by Evan Kodra, Karsten Steinhaeuser and Auroop Ganguly of Oak Ridge National Laboratory. The Southeast and Northwest regions of the United States may be especially vulnerable, the researchers conclude in their paper published in Geophysical Research Letters. The team used nine global climate models with a moderate greenhouse gas emissions scenario to compare 1991-2000 vs. 2091-2100. "Our findings suggest that despite a general warming trend, regional preparedness for extreme cold events cannot be compromised even toward the end of the century," said Ganguly, who described the findings as counterintuitive. [Contact: Ron Walli, (865) 576-0226; wallira@ornl.gov]

ELECTRONICS -- Phase transitions breakthrough

By reducing a material to the same nano scale as the electronic regions that reside within, researchers have gained a better understanding of the dynamics of electronic phase transitions. This information is critical to advances in several technologies that rely on competing resistive states such as random access memory for computers, low-energy magnetic cooling and next-generation materials to detect light. These findings, published by a team led by Oak Ridge National Laboratory's Zac Ward, appear in Physical Review B. Using this strategy to confine a material, the researchers found that they can isolate and observe the effects of electric field, temperature and current on a single or a few of these regions as they seed, grow and transition. [Contact: Ron Walli, (865) 576-0226; wallira@ornl.gov]

VEHICLES -- "Just in time"

A newly patented technology from Oak Ridge National Laboratory can help extend the lifetime of batteries in plug-in hybrid vehicles by optimizing the battery's state of charge while driving. Developed by ORNL's Robert DeVault, the computerized control uses data about recharging locations to improve the coordination of the battery and engine operation for trips beyond the vehicle's electric range. Knowing where charging stations are located can improve how the vehicle rations its battery power for longer battery life. By maintaining a higher state-of-charge during most of a trip, the patented control ensures that the battery enters a final discharge mode at the end of a trip "just in time" to obtain maximum recharging from the electric grid. "If you don't know where the trip is going to end, the engine's generator will make more electricity then you need to get to where you plug in. That lowers efficiency, reduces capacity for getting electricity from the grid, and wastes fuel because you're operating the engine more than needed," DeVault said. Patent variations include the ability to implement the "just in time" control method without a navigation system or driver input. [Contact: Morgan McCorkle; (865) 574-7308; mccorkleml@ornl.gov]

Source: DOE/Oak Ridge National Laboratory