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Professor George KarniadakisPNNL's Karniadakis likes exploring new territory

Professor George Karniadakis admits that it was the appeal of the unknown that attracted him to the field of mesoscopic modeling of materials.  “It’s really the least explored area, in terms of math modeling,” he says. “And it’s a critical area because it affects molecular scale, a critical element in designing new smart materials.”

Karniadakis, a professor of Applied Mathematics at Brown University who has a joint appointment at DOE's Pacific Northwest National Laboratory, was also one of the first to focus on uncertainty quantification, which is now one of the fastest growing areas of modeling and simulation research. He is now turning his attention toward another emerging field, fractional differential equations, including organizing an international workshop that will be held later this year.  “It’s totally unexplored,” he says. “That’s my favorite part – exploring new fields in math and engineering and being at the leading edge as these new horizons open.”

That’s the formula he’s followed since earning his Ph.D. more than 25 years ago. His path has included time at the Massachusetts Institute of Technology (his alma mater) and Princeton, as well as serving as a visiting professor at Caltech and Peking University, before he joined Brown in 1994.

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Schematic of active optical control of terahertz waves in electromagnetically induced transparency metamaterials.'Slow light' advance could speed optical computing, telecommunications

Wireless communications and optical computing could soon get a significant boost in speed, thanks to “slow light” and specialized metamaterials through which it travels.

Researchers have made the first demonstration of rapidly switching on and off “slow light” in specially designed mate­rials at room temperature. This work, which includes scientists from DOE's Los Alamos National Laboratory, opens the possibility to design novel, chip-scale, ultrafast devices for applications in terahertz wireless communications and all-optical computing.

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See also…

DOE Pulse
  • Number 384  |
  • March 18, 2013
  • X-ray laser sees photosynthesis in action

    These tiny green crystals, measuring just millionths of a meter, preserve the molecular structure and activity of Photosystem II, which carries out the oxygen-releasing process in photosynthesis. The chlorophyll-containing crystals, which have a boxlike structure, were studied at room temperature using ultrashort X-ray pulses at SLAC's Linac Coherent Light Source X-ray laser. The image was taken with a light microscope. (Credit: Jan Kern / Lawrence Berkeley National Laboratory) Opening a new window on the way plants generate the oxygen we breathe, researchers used an X-ray laser at DOE's SLAC National Accelerator Laboratory to simultaneously look at the structure and chemical behavior of a natural catalyst involved in photosynthesis for the first time.

    The work, made possible by the ultrafast, ultrabright X-ray pulses at SLAC’s Linac Coherent Light Source (LCLS), is a breakthrough in studying atomic-scale transformations in photosynthesis and other biological and industrial processes that depend on catalysts, which efficiently speed up reactions. The research is detailed in a Feb. 14 paper in Science.

    “All life that depends on oxygen is dependent on photosynthesis,” said Junko Yano, a Lawrence Berkeley National Laboratory chemist and co-leader in the experiment. “If you can learn to do this as nature does it, you can apply the design principles to artificial systems, such as the creation of renewable energy sources. This is opening up the way to really learn a lot about changes going on in the catalytic cycle.”

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  • Collaboration puts natural gas on the road

    Improved metal-organic frameworks. DOE's Savannah River National Laboratory, in partnership with Ford Motor Company, the University of California-Berkeley, and BASF, has research underway to explore an innovative low-pressure material-based natural gas fuel system for automobiles and other light vehicles. 

    The Advanced Research Projects Agency-Energy (ARPA-E) funded project is looking to accelerate the use of natural gas in vehicles by reducing the pressure of on-board tanks with a proposed technology using adsorbed natural gas (ANG). The project will use high surface area materials within a heat exchange system to increase the natural gas density far beyond that which can be achieved at similar pressures.

    The first focus of the project is to develop improved metal-organic frameworks to adsorb the natural gas at high densities.  Building on SRNL’s extensive knowledge of hydrogen storage materials and systems, researchers here are responsible for designing and testing high performance fuel systems to use these next-generation metal-organic frameworks.  This innovative research has the potential to lower the cost of storage tanks and compressors at the fueling station, resulting in increased use of natural gas vehicles. 

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  • Genes key to mercury mystery

    Genes key to mercury mystery

    By identifying two genes required for transforming inorganic into organic mercury, which is far more toxic, scientists have taken a significant step toward protecting human health.

    The question of how methylmercury, an organic form of mercury, is produced by natural processes in the environment has stumped scientists for decades, but a team led by researchers at DOE's Oak Ridge National Laboratory has solved the puzzle. Results of the study, published in the journal Science, provide the genetic basis for this process, known as microbial mercury methylation, and have far-reaching implications.

    "Until now, we did not know how the bacteria convert mercury from natural and industrial processes into methylmercury," said ORNL's Liyuan Liang, a co-author and leader of a large Department of Energy-funded mercury research program that includes researchers from the University of Missouri-Columbia and University of Tennessee.

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  • Maingi adds a new strategic dimension to fusion and plasma physics research

    Rajesh Maingi

    Physicist Rajesh Maingi remembers nearly everything. Results of experiments he did 20 years ago play back instantly in his mind, as do his credit card and bank account numbers.

    His knack for recalling research results comes in particularly handy. “Knowing results from five-to-20 years ago makes it easier to ask the right questions for contemporary scientific programs,” Maingi said. Such findings have made him a leading expert on key aspects of the physics of plasma, the superhot, charged gas that fuels fusion reactions in donut-shaped magnetic facilities called tokamaks.

    Maingi brings his expertise to the new position of manager of edge physics and plasma-facing components at the U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL).  The recently created post calls for coordinating all Laboratory research on the volatile edge of the plasma, which must be carefully controlled for fusion to take place, and on the crucial boundary between the plasma and the interior surfaces of a tokamak.

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