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The “Jaguar” - the most powerful computer in the world - will be used to design the next generation of nuclear reactors, according to an Oak Ridge National Lab press release.

The goal is to integrate existing nuclear energy and nuclear national security modeling and simulation capabilities with high-performance computing to simulate radiation in order to support the design and safety of nuclear facilities, improve reactor core designs and nuclear fuel performance and ensure the safety of nuclear materials, such as spent nuclear fuel.

John Wagner, technical integration manager for nuclear modeling at ORNL says, “We’re now simulating entire nuclear facilities, such as a nuclear power reactor facility with its auxiliary buildings and the ITER fusion reactor, with much greater accuracy than any other organization that we’re aware of.”

“Software for modeling radiation transport has been around for a long time,” he adds, “but it hadn’t been adapted to build on developments that have revolutionized computational science. There’s no special transformational technology in this software; but it’s designed specifically to take advantage of the massive computational and memory capabilities of the world’s fastest computers.”

The project has been awarded eight million processor hours on Jaguar for the purpose of developing a “uniquely detailed simulation of the power distribution inside a nuclear reactor core.” This is expected to cut years off the process of designing new and better reactors.

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Through new collaborations totaling $6.2 million, ORNL will be partnering with industry to overcome challenges facing lithium-ion manufacturing. Partners include A123 Systems, Dow Kokam, Porous Power Technologies and Planar Energy. In each case, industry cost-share exceeds 50 percent of the total project cost.

“By leveraging our expertise in materials science and manufacturing, ORNL will assist these partners with their individual energy storage challenges and address opportunities to surpass non-domestic secondary battery manufacturers that dominate today’s market,” says ORNL’s Energy Materials Program director Craig Blue in an ORNL press release.

The research teams will focus efforts on safety, service life and cost reduction.

Secondary Li-ion cell manufacturing encompasses a broad range of disciplines including formulation chemistry, film casting, polymer processing, materials and composite design, interfacial science and component engineering.

According to ORNL’s David Wood, co-principal investigator and technical lead on the project, collaborative research is expected to take place during the next 18 months. Wood adds, “This is a unique and timely opportunity for ORNL to help government and industry set the course for a new generation of energy storage technologies.”

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Credit: LLNL

According to a release from the Lawrence Livermore National Lab, a new element has been discovered, one that resides in a tiny slice of paradise called the island of stability. Element 117– yet to receive a formal name – is the fifth new element scientists have discovered in the past decade.

“The discovery of element 117 is the culmination of a decade-long journey to expand the periodic table and write the next chapter in heavy-element research,” says Yuri Oganessian, scientific leader of the Flerov Laboratory of Nuclear Reactions at the Joint Institute of Nuclear Research and spokesperson for the collaboration. JINR is a Russia-based international intergovernmental research organization.

Although these elements only appear in the lab, some researchers say they may occur in nature as extremely rare, fleeting by-products of supernova.

The quest has increasingly been driven by what nuclear physicists call the island of stability – a range of very heavy elements, not yet created, that theory suggests should remain stable far longer than many of the elements researchers have created in the lab so far.

Finding element 117 took patience. According to the LLNL website, the effort took two years. It began at the High Flux Isotope Reactor at the Oak Ridge National Lab with a 250-day irradiation to produce 22 mg of berkelium. This was followed by 90 days of processing at ORNL to separate and purify the berkelium. Then, lab in Dimitrovgrad, Russia, had to prepare the berkelium target. Finally, calcium ions were fired at the target for 150 days. And, that was cutting it close: Berkelium has a half-life of only 320 days.

The result: six atoms of element 117. The atoms existed for between 21 and 45 millionths of a second.

The team included scientists from the JINR (Dubna, Russia), the Research Institute for Advanced Reactors (Dimitrovgrad), Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, Vanderbilt University and the University of Nevada, Las Vegas.

“This is a significant breakthrough for science,” LLNL director George Miller says. “The discovery of a new element provides new insight into the makeup of the universe and is a testimony to the strength of science and technology at the partner institutions.”

The team now is gearing up to probe element 117’s chemical properties. The team’s results appear in a research paper accepted for publication in the journal Physical Review Letters.

Check out the animation of the creation of element 117 here.

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Via press release, researchers at Oak Ridge National Lab working toward a low-cost DNA sequencing tool for medical diagnostics have proposed using a single-walled carbon nanotube to thread a single strand of DNA from one reservoir to another, analyzing and sequencing the DNA in the process.

In such a device, the negatively charged DNA material, which is immersed in an electrolytic fluid, is propelled through the nanotube by an electric field.

When the current flowing through the nanotube was measured, researchers were surprised by the current of electrolytic ions that was much higher than any prediction.

Arizona State University’s Predrag Krstic and former ORNL researcher Sony Joseph performed atomistic molecular and fluid dynamics simulations at the University of Tennessee’s National Institute for Computational Sciences, located at ORNL.

Krstic and Joseph, in a paper published with their Arizona State and Columbia collaborators in the Jan. 1, 2010, issue of Science, attributed the mysterious current surge to the “slipping” of water molecules through the perfect and hydrophobic inner surface of the carbon nanotube and to trapped electrical charge.

Understanding such phenomena is key to the development of these single-molecule-detection instruments that would be inexpensive enough to become common in doctor’s offices.

“This is an example of how the front of science is increasingly multidisciplinary, with contributions by experimentalists and theorists in atomic and solid-state physics, chemistry, biology and engineering,” says Predrag.

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According to a press release, Oak Ridge National Lab, via its Center for Nanophase Materials Sciences Division, is developing a chemical and biological sensor with unprecedented sensitivity.

The device consists of a digital camera, a laser, imaging optics, a signal generator, digital signal processing and other components that can detect tiny amounts of substances in the air.

Researchers believe this new “sniffer” will achieve a detection level that approaches the theoretical limit, surpassing other state-of-the-art chemical sensors. The implications could be significant for anyone whose job is to detect explosives, biological agents and narcotics.

“While the research community has been avoiding the nonlinearity associated with the nanoscale mechanical oscillators, we are embracing it,” says co-developer Nickolay Lavrik, a researcher in the CNMS. “In the end, we hope to have a device capable of detecting incredibly small amounts of explosives compared to today’s chemical sensors.”

The approach makes use of microcantilevers similar to those used in atomic force microscopy. The microcanilevers serve as microresonators that measure changes in the resonance frequency due to mass changes. Although the concept is relatively simple, assembling a working model is more difficult.

“These challenges are due to requirements of measuring and analyzing tiny oscillation amplitudes that are about the size of a hydrogen atom,” Lavrik reports. He says previous approaches would have required sophisticated low-noise electronic components such as lock-in amplifiers and phase-locked loops, which add cost and complexity.

This new type of sniffer works by deliberately hitting the microcantilevers with relatively large amounts of energy associated with a range of frequencies, forcing them into wide oscillation.

“In the past, people wanted to avoid this high amplitude because of the high distortion associated with that type of response,” says ORNL’s Panos Datskos, a member of the Measurement Science and Systems Engineering Division. “But now we can exploit that response by tuning the system to a very specific frequency that is associated with the specific chemical or compound we want to detect.”

When the target chemical reacts with the microcantilever, it shifts the frequency depending on the weight of the compound, thereby providing the detection.

“With this new approach, when the microcantilever stops oscillating we know with high certainty that the target chemical or compound is present,” Lavrik says.

The researchers envision this technology being incorporated in a handheld instrument that could be used by transportation security screeners, law enforcement officials and the military. Other potential applications are in biomedicine, environmental science, homeland security and analytical chemistry.

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