28-Aug-2014 Materials scientists play atomic 'Jenga' and make a surprising discovery
Researchers got a surprise when they built a highly ordered lattice by layering thin films containing lanthanum, strontium, oxygen and iron. Although each layer had an intrinsically nonpolar (symmetric) distribution of electrical charges, the lattice had an asymmetric distribution of charges. The charge asymmetry creates an extra 'switch' that brings functionalities to materials when 'flipped' by external stimuli. The material defects induced polar behavior and can provide a new mechanism for manipulating electricity and magnetism in energy and information technologies.
22-Aug-2014 Catalytic gold nanoclusters promise rich chemical yields
With scientists from Carnegie Mellon University, researchers at the Department of Energy's Oak Ridge National Laboratory have found a catalyst containing exactly 25 gold atoms that catalyzes the conversion of various molecules, including the transformation of poisonous carbon monoxide into harmless carbon dioxide, a reaction that may find application in devices near gas flues or wood-burning stoves.
25-Apr-2014 'Sweet spot' for salty water
Computational modeling has given materials researchers new insight into the properties of a membrane that purifies saltwater into potable water. The resulting technology could help speed up inefficient desalination processes in use today.
11-Apr-2014 Simulation solves mystery of how liquid-crystal thin films disintegrate
Approximately four decades ago, theoreticians believed that only one of two mechanisms could explain rupture of liquid-crystal thin films. They also believed that these two mechanisms could not coexist. But 10 years ago experiments showed that these two mechanisms in many cases do coexist, according to Trung Nguyen of Oak Ridge National Laboratory, who ran unprecedented large-scale molecular dynamics simulations on Titan, America's fastest supercomputer, to model the beginnings of ruptures in thin films.
11-Apr-2014 Oak Ridge National Laboratory researchers contribute to prestigious climate report
Thomas Wilbanks and Benjamin Preston, both of the Climate Change Science Institute at Oak Ridge National Laboratory, are among the 309 coordinating lead authors of the Intergovernmental Panel on Climate Change's Working Group II report. The report, which was released in Japan on March 31, found that climate change isn't just a problem for future generations, but also impacts humans in the present day.
29-Jan-2014 Letting in the light
Oak Ridge National Laboratory is developing a low-cost, transparent, anti-soiling coating for solar reflectors to optimize energy efficiency while lowering operating and maintenance costs and avoiding negative environmental impacts.
17-Jul-2012 Special report: Graphics processing units speed results in extreme-scale supercomputers
Can scientists and engineers benefit from extreme-scale supercomputers that use application-code accelerators called GPUs (graphics processing units)? Comparing GPU accelerators with today's fastest central processing units (CPUs), early results from diverse areas of research show 1.5- to 3-fold speedups for most codes. That acceleration means increased realism of simulations and decreased time to results. A special report details these findings.
24-May-2012 Supernovas explode in 3-D detail at Oak Ridge National Laboratory
Understanding a Type Ia supernova -- an exploding white dwarf star -- requires supercomputers. A team of astrophysicists and computational scientists is using the power of Oak Ridge National Laboratory's Jaguar to virtually blow up these white dwarfs. In the process the researchers are revealing the secrets of the biggest thermonuclear explosions in the universe and finding the answers needed to measure the size of the universe.
4-Apr-2012 Carbon dioxide caused global warming at ice age's end, pioneering simulation shows
Climate science has an equivalent to the "what came first -- the chicken or the egg?" question: what came first, greenhouse gases or global warming? A multi-institutional team led by researchers at Harvard, Oregon State University, and the University of Wisconsin used a global dataset of paleoclimate records and the Jaguar supercomputer at Oak Ridge National Laboratory to find the answer. The results, published in the April 5 issue of Nature, analyze 15,000 years of climate history.
29-Feb-2012 Climate scientists compute in concert
Researchers at Oak Ridge National Laboratory are sharing computational resources and expertise to improve the detail and performance of a scientific application code that is the product of one of the world's largest collaborations of climate researchers. The Community Earth System Model couples components of atmosphere, land, ocean, and ice to reflect their complex interactions. By continuing to improve science representations and numerical methods in simulations, and exploiting modern computer architectures, researchers expect to further improve the CESM's accuracy in predicting climate changes.
29-Feb-2012 Computation proves predictive capabilities of nuclei through fluorine-14 simulation
Aa team led by Iowa State University physicist James Vary used Oak Ridge Leadership Computing Facility and Argonne Leadership Computing Facility resources to predict the behavior of fluorine-14, a relatively unknown isotope. It published its predictions in Physical Review C in February 2010. Six months later, a group of researchers at Texas A&M University's Cyclotron Institute performed an experiment producing fluorine-14, and the results nearly mirrored those of Vary's group.
8-Feb-2012 Computer scientists collect computing tools for next-generation machines
Researchers using the Oak Ridge Leadership Computing Facility's can foresee substantial changes in scientific application code development. The OLCF's new supercomputer, Titan, will use a hybrid architecture of conventional, multipurpose CPUs and high-performance GPUs. The machine will supplant the OLCF's current fastest supercomputer, Jaguar, a Cray XT5 using an entirely CPU-based platform. Members of the OLCF's Application Performance Tools group understand the challenge. Their goal is to make the transition as smooth as possible.
27-Dec-2011 Materials modeling shows big future for boron nitride nanoribbons
Alejandro Lopez-Bezanilla at Oak Ridge National Laboratory studies a proposed graphene substrate: boron nitride. Graphene, which is carbon in the form of freestanding 1-atom-thick sheets, is a natural for next-generation computer chips, communications equipment, and solar energy devices. Electrons flow through the material at an astonishing 1 million meters per second. To live up to its potential, however, graphene needs support. On its own, its edges wrinkle, tear, or roll up.
5-Dec-2011 Big business and big science partner in computing to speed products to market
Jack Wells spoke about collaborative opportunities in high-performance computing at the Oak Ridge Leadership Computing Facility. He highlighted pathways by which industrial users can gain access to supercomputers. Approximately 60 percent of time available on Jaguar, America's fastest supercomputer, is allocated through the Innovative and Novel Computational Impact on Theory and Experiment program, whereas 30 percent is allocated through the Office of Advanced Scientific Computing Research Leadership Computing Challenge and 10 percent through Director's Discretion.
17-Nov-2011 'Colony' software speeds up high-performance computing processes
As the number of processors continues to increase in leadership-class supercomputers, their ability to perform parallel computation -- doing multiple calculations simultaneously -- becomes increasingly important. The surge in machine size and complexity has led the Oak Ridge Leadership Computing Facility computer scientists to try new and interesting strategies to keep large systems running at the highest efficiency. Their efforts have nearly tripled performance for synchronizing collective operations.
9-Nov-2011 Researchers show how proteins help DNA replicate past a damaged site
A multi-institutional research team led by Ivaylo Ivanov of Georgia State University has employed the Jaguar XT4 supercomputer at Oak Ridge National Laboratory and X-rays a billion times brighter than the sun, produced at Lawrence Berkeley National Laboratory, to illuminate how DNA replication continues past a damaged site so a lesion can be repaired later. The results appear in the Oct. 17, 2011, online issue of Proceedings of the National Academy of Sciences.
15-Sep-2011 Simulating turbulent combustion speeds design of power and propulsion devices
A team led by mechanical engineers Joseph Oefelein and Jacqueline Chen of Sandia National Laboratories simulates turbulent combustion at different scales. Chen and Oefelein were allocated 113 million hours on Oak Ridge Leadership Computing Facility's Jaguar supercomputer in 2008, 2009 and 2010 to simulate autoignition and injection processes with alternative fuels. For 2011 they received 60 million processor hours for high-fidelity simulations of combustion in advanced engines.
19-Aug-2011 Supercomputers and airplanes help model hurricane structure and intensity
Information from major hurricanes such as Katrina is being put to good use by scientists striving to understand how hurricanes intensify. A research team led by Jon Reisner of Los Alamos National Laboratory is employing the Oak Ridge Leadership Computing Facility's Jaguar supercomputer to use data from lightning detectors and even wind instruments mounted on planes flown into the eye of a hurricane to improve atmospheric models. These simulations may lead to more accurate prediction of hurricane intensities.
The Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time.