August 2018Story tips from the Department of Energy’s Oak Ridge National Laboratory


Contagious conservation

A team led by Oak Ridge National Laboratory has discovered that residents living in arid environments share a desire for water security, which can ultimately benefit entire neighborhoods. Las Vegas, Nevada’s water utility was the first utility in the United States to implement a water conservation program in which homeowners receive cash incentives for replacing water-hungry grass with plants better suited to an arid climate. Researchers analyzed 15 years of data across 16 neighborhoods to determine whether one home’s participation in the program had a measurable effect on their neighbors’ likelihood of also participating. “The water agencies’ thinking is: if one person’s participation induces conservation behavior in some of their neighbors, then everybody wins,” ORNL’s Christa Brelsford, lead coauthor of the study, said. This work, the third in a series, was published in the journal Networks and Spatial Economics. [Contact: Sara Shoemaker, (865) 576-9219; shoemakerms@ornl.gov]

Image: https://www.ornl.gov/sites/default/files/news/images/01%20-%20PeerEffectsMap.png

Caption: Researchers analyzed 15 years of data across 16 neighborhoods, shown in orange, in the Las Vegas Valley Water District to determine whether one home’s participation in the utility’s water conservation program had a measurable effect on their neighbors’ likelihood of also participating. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

Buildings—3-D printing molds

The construction industry may soon benefit from 3-D printed molds to make concrete facades, promising lower cost and production time. Researchers at Oak Ridge National Laboratory are evaluating the performance of 3-D printed molds used to precast concrete facades in a 42-story building. Molds are typically handmade from wood and fiberglass coatings, and they must be resurfaced after 20 to 30 pours. A 3-D printed mold could potentially cast up to 200 pieces. “With 3-D printed molds, architects can create complex designs for cornices and columns that they have not previously explored,” said ORNL’s Diana Hun. The research team used large-scale additive manufacturing technology to produce the molds, which are about as large as a queen size mattress. Industry partners were Gate Precast and Precast Concrete Institute. [Contact: Jennifer Burke, (865) 576-3212; burkejj@ornl.gov]

Image: https://www.ornl.gov/sites/default/files/news/images/02%20-%203D-printed_precast_concrete_molds.gif

Caption: Researchers 3-D printed molds for precasting concrete using the Big Area Additive Manufacturing, or BAAM™, system at DOE’s Manufacturing Demonstration Facility at ORNL. Complex, durable mold designs can be produced in less time than traditional wood or fiberglass molds. Credit: Jason Richards/Oak Ridge National Laboratory, U.S. Dept. of Energy

Materials—Engineering nanopore edges

An Oak Ridge National Laboratory-led team has learned how to engineer tiny pores embellished with distinct edge structures inside atomically-thin two-dimensional, or 2-D, crystals. The 2-D crystals are envisioned as stackable building blocks for ultrathin electronics and other advanced devices, but their edges and pores are especially reactive for catalysis, sensing or separations functions. Their formation and structure had not been well understood to date. Using a heating microchip inside a scanning transmission electron microscopy at ORNL’s Center for Nanophase Materials Sciences, the scientists induced changes in the local chemical environment of a 2-D material to reveal the atomic rearrangements leading to the formation of different nanopore edges. Theorists’ predictions from thermodynamics explained the four stable configurations that formed most often. “Before, we had to take whatever we got from a materials’ synthesis,” said ORNL’s Xiahan Sang. “Now we can be proactive at creating edges.” The work was published in Nature Communications. [Contact: Dawn Levy, (865) 576-6448; levyd@ornl.gov]

Image: https://www.ornl.gov/sites/default/files/news/images/03%20-%20MoWSe2%20StoryTip%20Fig_PRINT%20r1_0.jpg

Caption: An ORNL-led team used scanning transmission electron microscopy to observed atomic transformations on the edges of pores in a two-dimensional transition metal dichalcogenide. The controlled production of nanopores with stable atomic edge structures may enable new functional applications. Credit: Xiahan Sang/Oak Ridge National Laboratory, U.S. Dept. of Energy

Nuclear—Little runaways

Fusion scientists from Oak Ridge National Laboratory are studying the behavior of high-energy electrons when the plasma that generates nuclear fusion energy suddenly cools during a magnetic disruption. Fusion energy is created when hydrogen isotopes are heated to millions of degrees. A sudden cool down, or thermal quench, produces runaway electrons that could veer off and seriously damage the inner wall of the fusion reactor. Using a recently developed simulation tool, the Kinetic Orbit Runaway electron Code, or KORC, scientists calculated the particle dynamics and radiation in the plasma’s electric and magnetic fields. “Runaway electrons are a serious potential threat to fusion reactors,” said ORNL’s Diego del-Castillo-Negrete. “With a better understanding of the relativistic dynamics of these particles, we can develop strategies to mitigate or avoid them.” The team’s findings were published in the journal Physics of Plasmas. [Contact: Sara Shoemaker, (865) 576-9219; shoemakerms@ornl.gov]

Image 1: https://www.ornl.gov/sites/default/files/Fusion_plasma_simulation.gif

Image 2: https://www.ornl.gov/sites/default/files/04a%20-%20Cross-section_fusion_simulation_runaways_1.gif

Caption: The KORC simulation of runaway electrons in the experimental tokamak at the DIII-D National Fusion Facility at General Atomics shows examples of particle orbits and the synchrotron radiation emission pattern at a cross section of the device. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

Hydropower—A river of data

Oak Ridge National Laboratory has created new tools to better understand the nation’s waterways and identify potential sites to generate hydropower—a domestic renewable energy resource. The tools allow users such as scientists, resource agencies and industry to access information about the natural features and ecological characteristics of streams and to assess potential sites to install low-cost, small-footprint hydropower technologies. “The stream classification tool gives stakeholders shared insights into the essential nature of millions of American streams,” said Brennan Smith, manager of ORNL’s water power technologies program. “The siting tool simplifies and clarifies site evaluation by matching advanced standardized modular hydropower technology to this essential nature of streams.” Analytics from the stream classification and siting capabilities build on the rich hydropower data generated by the laboratory. [Contact: Kim Askey, (865) 576-2841; askeyka@ornl.gov]

Image 1: https://www.ornl.gov/sites/default/files/05a%20-%20Alternate_site_assessment_1.png

Caption: The ORNL-developed site assessment tool, dubbed SMH Explorer, provides a platform to develop small modular hydropower technologies by identifying common physical and environmental characteristics in stream segments across the nation. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

Image 2: https://www.ornl.gov/sites/default/files/05b%20-%20Stream%20classification2_0.PNG

Caption: The U.S. stream classification tool allows users to select streams that share similar properties and functions to serve as reference sites or ecological case studies. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

Magnets—Print, power, repeat

Oak Ridge National Laboratory scientists have improved a mixture of materials used to 3-D print permanent magnets with increased density, which could yield longer lasting, better performing magnets for electric motors, sensors and vehicle applications. Building on previous research, they combined thermoplastic nylon polymer with neodymium-iron-boron magnet powders into pellets of feedstock materials. Using innovative additive manufacturing techniques allows the team to print permanent magnets into complex shapes without wasting material. Plus, the resulting magnets can be converted back to a feedstock and reprinted as new magnets if needed. “This is especially important considering magnets of this caliber are typically made with critical rare earth elements, which are in short supply and difficult to acquire,” said ORNL’s Parans Paranthaman. The scientists demonstrated the performance of the 3-D printed magnets against sintered ferrite magnets in a small, direct-current motor. They published their results in Additive Manufacturing and the Journal of Magnetism and Magnetic Materials. [Contact: Sara Shoemaker, (865) 576-9219; shoemakerms@ornl.gov]

Image: https://www.ornl.gov/sites/default/files/news/images/06%20-%203D-printed_permament_magnet_0.jpg

Caption: 3-D-printed permanent magnets with increased density were made from an improved mixture of materials, which could lead to longer lasting, better performing magnets for electric motors, sensors and vehicle applications. Credit: Jason Richards/Oak Ridge National Laboratory, U.S. Dept. of Energy

More information:
Christa Brelsford et al, Are ‘Water Smart Landscapes’ Contagious? An Epidemic Approach on Networks to Study Peer Effects, Networks and Spatial Economics (2018). DOI: 10.1007/s11067-018-9416-z

Provided by Oak Ridge National Laboratory

This Phys.org Science News Wire page contains a press release issued by an organization mentioned above and is provided to you “as is” with little or no review from Phys.Org staff.



Source link

Leave a Reply