For more than 50 years, scientists have debated what turns particular oxide insulators, in which electrons barely move, into metals, in which electrons flow freely.
Throw a rock through a window made of silica glass, and the brittle, insulating oxide pane shatters. But whack a golf ball with a club made of metallic glass—a resilient conductor that looks like metal—and the glass not only stays intact but also may drive the ball farther than conventional clubs. In light of this contrast, the nature of glass seems anything but clear.
When Orlando Rios first started analyzing samples of carbon fibers made from a woody plant polymer known as lignin, he noticed something unusual. The material’s microstructure -- a mixture of perfectly spherical nanoscale crystallites distributed within a fibrous matrix -- looked almost too good to be true.
The Department of Energy’s Oak Ridge National Laboratory concluded a series of workshops this month that engaged scientists from around the country to identify grand scientific challenges and how they might be addressed through application of neutron science.
In 2015, American consumers will finally be able to purchase fuel cell cars from Toyota and other manufacturers. Although touted as zero-emissions vehicles, most of the cars will run on hydrogen made from natural gas, a fossil fuel that contributes to global warming.
If such a designation existed, Nazanin Bassiri-Gharb would be on the fast track to becoming an Oak Ridge National Laboratory “super user.” Her research on nanoscale materials has taken her all across the ORNL campus, from scanning probe and electron microscopes at the Center for Nanophase Materials Sciences to neutron reflectometry at the Spallation Neutron Source and radiation equipment in the Materials Science and Technology Division.
Old thinking was that gold, while good for jewelry, was not of much use for chemists because it is relatively nonreactive. That changed a decade ago when scientists hit a rich vein of discoveries revealing that this noble metal, when structured into nanometer-sized particles, can speed up chemical reactions important in mitigating environmental pollutants and producing hard-to-make specialty chemicals.
Neutron scattering research at the Department of Energy’s Oak Ridge National Laboratory has revealed clear structural differences in the normal and pathological forms of a protein involved in Huntington’s disease.
The Spallation Neutron Source at the Department of Energy’s Oak Ridge National Laboratory broke records for sustained beam power level as well as for integrated energy and target lifetime in the month of June.
The American Conference on Neutron Scattering returned to Knoxville this week, 12 years after its inaugural meeting there in 2002.