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IMAGE: The Polarstern R / V icebreaker was carrying more than 60 ARM tools for the MOSAiC expedition. View More
Credit: US Dept. of Energy ARM User Facility
Climate: icebreaker data
With the conclusion of an unprecedented year-long expedition to the North Pole called MOSAiC, data from instruments installed on an Arctic ice floe is available to the scientific community to improve models that predict the planet’s environmental future.
The Oak Ridge National Laboratory researchers were part of an international team that collected a treasure trove of data measuring precipitation, air particles, cloud patterns, and energy exchange between the atmosphere and sea ice. The data was acquired from a suite of 63 instruments from the Department of Energy’s Atmospheric Radiation Measurement User Facility. ORNL has processed these measurements and made huge amounts of observational data easily accessible and usable for climate modellers.
“We have never had this kind of data for the northernmost parts of the Arctic,” said Giri Prakash, director of the ARM Data Center at ORNL. “These data will be an invaluable resource for scientists to improve predictions of global environmental changes.”
Media Contact: Kim Askey, 865.576.2841, [email protected]
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Caption: Researchers installed ARM instruments on the ice floe near the ship that served as a home during the MOSAiC expedition. Credit: US Dept. of Energy ARM User Facility
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Title: The instruments of the radiometer collect data on Arctic ice. Credit: US Dept. of Energy ARM User Facility
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Caption: The R / V Polarstern icebreaker was carrying more than 60 ARM instruments for the MOSAiC expedition. Credit: US Dept. of Energy ARM User Facility
Biology: rupture of the bacterial shield
An international research team has discovered a mechanism used by pathogenic bacteria to anchor their outer protective membranes. Their findings could inform strategies for destroying a microbe’s cellular structure, ultimately helping to fight pathogens affecting humans and plants.
Scientists at Oak Ridge National Laboratory used high-performance computing to create protein models that helped reveal how the outer membrane is bound to the cell membrane in some bacteria. These Gram-negative bacteria enclose their cell walls between an outer and an inner membrane, and the layers act as a shield allowing them to persist in harsh conditions.
The ORNL models informed further simulations and experiments by collaborators who observed these unusual connections.
“Modeling and simulating membrane proteins help us understand complex cell structures,” said Jerry Parks of ORNL. “These approaches are particularly important when relatively little is known about an organism, because it is difficult to study in the laboratory.”
Media Contact: Kim Askey, 865.576.2841, [email protected]
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Caption: ORNL collaborated in the study of proteins called porins, one shown in red, which are found in the outer protective membrane of some pathogenic bacteria and bind the membrane to the cell wall. Credit: Hyea (Sunny) Hwang / Georgia Tech and ORNL, United States Department of Energy
Batteries – Heat capture
Researchers from Oak Ridge National Laboratory have shown that the cathode heat carrying capacity of lithium-ion batteries is much lower than previously determined, a finding that could help explain the obstacles to increasing storage capacity. energy and increased performance.
Research on lithium-ion batteries, used primarily in smartphones and laptops, has shown that less heat transport is hindered, which leads to lower energy density and lower performance.
In the study, the researchers used quantum mechanical calculations to predict the inherent heat-carrying capabilities of battery cathodes and the impacts of charge. Further evaluation looked at how the strong vibrational forces between the ions between the layers of the material can affect heat.
“We found that heat transport is more inefficient than expected due to the non-harmonic vibrational forces between the ions, which worsen during charging,” said ORNL’s Tianli Feng. “Our findings solve long-standing problems with heat transport and provide guidance on how to design future high-density batteries.”
Media Contact: Jennifer Burke, 865.414.6835, [email protected]
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Caption: ORNL researchers determined that the lower heat exchange in lithium-ion batteries is caused by the strong non-harmonic forces between the ions and the weak interaction between the layers, providing guidance for the design of high-density batteries. Credit: Tianli Feng / ORNL, United States Department of Energy
Neutrons – Finding order in disorder
Researchers revealed a new understanding of disordered ceramics: materials with non-uniform atomic arrangements used in a variety of energy-related applications, including electronics, nuclear fuels and fuel cells.
Pauling’s rules are the standard model used to describe atomic arrangements in ordered materials. Neutron scattering experiments at Oak Ridge National Laboratory confirmed that this approach can also be used to describe highly disordered materials.
The researchers demonstrated the model’s ability to determine the distance between neighboring atoms and predict how the atoms move once the disturbance is introduced. The new knowledge overturns the conventional wisdom that ions in disordered materials are mixed randomly, but instead arrange themselves in blocks with a high degree of order.
“The disorder is the basis of many interesting properties and applications,” said Maik Lang of the University of Tennessee and corresponding author of the Advances in science she studies. “A better understanding of how these materials behave could lead to better materials with more functionality.”
Media Contact: Jeremy Rumsey, 865. 576.2038, [email protected]
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Caption: UTC researchers used neutron probes at ORNL to confirm that established fundamental chemical rules can also help understand and predict atomic movements and distortions in materials when disorder is introduced, as arrows show. Credit: Eric O’Quinn / UTK
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