image: From left, John Dutcher, Josh Sampson and John Atkinson of the University of Guelph prepare phytoglycogen nanoparticles found in corn to study on the EQ-SANS instrument at ORNL's Spallation Neutron Source. The team's findings could advance many biomedical and personal care applications. view more
Credit: Genevieve Martin/Oak Ridge National Laboratory, US Dept. of Energy
Biology--Methane mystery solved
Scientists at Oak Ridge National Laboratory have confirmed that methane-producing microorganisms known as methanogens are responsible for the greenhouse gas that leaks from living Eastern cottonwood trees in Southeastern forests. "There was debate about whether methane emitted by tree trunks came up the stem from the soil," said ORNL's Chris Schadt whose team published details in New Phytologist. "We've shown that the microbial community in the tree trunk is the primary source." The research team used gene sequence analyses to identify several species of methanogens thriving in the oxygen-deprived, water-saturated wood at the heart of these trees. Methane is about 34 times more powerful than carbon dioxide at trapping heat. Measurements of the microbial behavior of methanogens could help improve predictive climate models that track the potential heat-trapping effect of methane gas in the atmosphere. [Contact: Kim Askey, (865) 576-2841; askeyka@ornl.gov]
Image: https://www.ornl.gov/sites/default/files/Biology-methane_mystery_solved.jpg
Caption: Studies indicate that microorganisms in the tree trunks of living Eastern cottonwood trees emit the greenhouse gas methane. Credit: © 2018 Daniel Z. Yip, et al. New Phytologist © 2018 New Phytologist Trust
Neutrons--Nanosize matters
A team of scientists, led by University of Guelph professor John Dutcher, are using neutrons at ORNL's Spallation Neutron Source to unlock the secrets of natural nanoparticles that could be used to improve medicines. The nanoparticles, called phytoglycogen, are highly branched, water-soluble polymers of glucose produced by plants such as sweet corn and rice. At only 35 nanometers in diameter, phytoglycogen nanoparticles are a challenge to study. But discovering the source of their unique properties will enable the development of new technologies in personal care and biomedicine, which are being commercialized by spinoff company Mirexus Biotechnologies. "Neutrons are ideal for this research because they are sensitive to hydrogen, a key building block in phytoglycogen," said Dutcher. "The EQ-SANS and BASIS instruments at the Spallation Neutron Source are providing new insights vital to understanding the anti-aging properties of particles in cosmetics and engineering the improved delivery of cancer medications and production of vaccines from live cells." [Contact: Kelley Smith, (865) 576-5668; smithks@ornl.gov]
Caption: From left, John Dutcher, Josh Sampson and John Atkinson of the University of Guelph prepare phytoglycogen nanoparticles found in corn to study on the EQ-SANS instrument at ORNL's Spallation Neutron Source. The team's findings could advance many biomedical and personal care applications. Credit: Genevieve Martin/Oak Ridge National Laboratory, U.S. Dept. of Energy
Batteries--Solid-liquid interface
By studying the inner workings of lithium-ion batteries, Oak Ridge National Laboratory researchers have developed a highly sensitive technique to characterize and measure at the electrolyte and electrode interface. Their finding, published in ACS Nano, could help in understanding the fundamental factors that determine the composition and stability of solid electrolyte interphase, or SEI. "A robust SEI is key to the performance and safety of Li-ion batteries used to power electric vehicles," said ORNL's Jagjit Nanda. Li-ion batteries comprise positive and negative electrodes, each containing an electrolyte, or salt, solution, separated by a membrane. The researchers used surface enhanced Raman spectroscopy to evaluate how the lithium-salt interacts between the liquid electrolyte and electrode. "We found that the ion-solvation at the interface differs from what we observed in the bulk liquid electrolyte," he said. Understanding this phenomenon could lead to improved electrolytes resulting in batteries with higher performance and better stability. [Contact: Sara Shoemaker, (865) 576-9219; shoemakerms@ornl.gov]
Image: https://www.ornl.gov/sites/default/files/Li-ion_membrane_interface.jpg
Caption: ORNL researchers used surface-enhanced Raman spectroscopy, or SERS, from a gold nanoparticle monolayer, which is capable of depicting the solvation structure of cations in electrolytes near the solid-liquid interface in a lithium-ion battery. The nanogap SERS provides a unique, high-sensitive platform for studying the solvation structure and ion transport in a wide category of electrolyte systems at electrified interfaces. Credit: Guang Yang/Oak Ridge National Laboratory, U.S. Dept. of Energy
Reactors--Salty scenarios
Scientists from Oak Ridge National Laboratory performed a corrosion test in a neutron radiation field to support the continued development of molten salt reactors, or MSRs. MSRs use a liquid salt mixture that can serve as both the fuel and coolant. At high temperatures over time, these salts can react with the reactors' metal components if not properly monitored and maintained. "This is the first time in decades ORNL has performed this kind of corrosion study," ORNL's Joel McDuffee said. "The data are crucial for industry that are developing MSRs." The team tested stainless steel and nickel-based alloy samples in the Ohio State University Research Reactor at a sustained temperature of 800 degrees C. At ORNL, they will expose identical, unirradiated samples to the same conditions. Using microscopy techniques, they will examine the materials for signs of corrosion and compare results from the two experiments. [Contact: Sara Shoemaker, (865) 576-9219; shoemakerms@ornl.gov]
Image 1: https://www.ornl.gov/sites/default/files/exp_in_10_dry_tube.jpg
Caption: As part of the experiment's pretesting assembly, ORNL scientists prepared a casing that held stainless steel and nickel-based alloy samples into a dry tube. The alloy samples were corrosion tested at the Ohio State University Research Reactor. Credit: N. Dianne Bull Ezell/Oak Ridge National Laboratory, U.S. Dept. of Energy
Image 2: https://www.ornl.gov/sites/default/files/IMG_8484.jpg
Caption: Scientists at the Ohio State University Research Reactor lowered alloy samples into the reactor pool and exposed them to a sustained temperature of 800 degrees C as part of the corrosion test. Credit: Andrew Kauffman/Ohio State University research staff
Security--Sea of energy change
Thought leaders from across the maritime community came together at Oak Ridge National Laboratory to explore the emerging new energy landscape for the maritime transportation system during the Ninth Annual Maritime Risk Symposium. "The outcomes of this year's symposium are expected to help the maritime community prepare for the fast-approaching evolution of energy supply and consumption, which is bringing new risks as well as new opportunities," said ORNL's Craig Moss, an event organizer. Topping the list of emerging energy trends addressed were clean energy technologies, alternative fuels, resiliency, environmental stewardship and energy storage. Participants included universities, U.S. military, federal government and industry representatives. Co-organizers were ORNL, the U.S. Coast Guard and the National Academies of Science. [Contact: Amy Reed, (865) 241-3802, reedac@ornl.gov]
Caption: The Ninth Annual Maritime Risk Symposium addressed the emerging energy trends facing the maritime industry. Credit: Adam Malin/Oak Ridge National Laboratory, U.S. Dept. of Energy
Image: https://www.ornl.gov/sites/default/files/2018-P08808.jpg
Caption: Keynote speaker Rear Admiral Paul F. Thomas of the U.S. Coast Guard addressed major energy challenges facing the maritime industry, including growth in capacity, the challenge of reducing environmental impact, and the increasing complexity of not just technology but also safety, security and systems management. Credit: Carlos Jones/Oak Ridge National Laboratory, U.S. Dept. of Energy
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Journal
ACS Nano