Phys.org December 23, 2024 To understand the impact of mesoscale variability, including gravity waves (GWs), on atmospheric circulation, a team of researchers in the US (Stanford University, Oak Ridge National Laboratory) extracted data from four months of an integrated data at 1 km resolution (XNR1K) using the Integrated Forecast System (IFS) model. They computed zonal and meridional flux of vertical momentum from ~1.5 petabytes of data. The fluxes were validated using ERA5 reanalysis, both during the first week after initialization and over the boreal winter period from November 2018 to February 2019. The agreement between reanalysis and IFS demonstrated its […]
Tag Archives: S&T USA
Stretchable, flexible, recyclable: 3D printing method creates fantastic plastic
Phys.org December 13, 2024 Thermoplastic elastomers (TPEs) are nanostructured, melt-processable, elastomeric block copolymers. When TPEs that form cylindrical or lamellar nanostructures are macroscopically oriented, their material properties can exhibit several orders of magnitude of anisotropy. Researchers at Princeton University demonstrated that the flows applied during the 3D printing of a cylinder-forming TPE enables hierarchical control over material nanostructure and function. 3D printing allowed control over the extent of nanostructural and mechanical anisotropy. They had tunable local and macroscopic mechanical responses. They achieved melt-reprocessability over multiple cycles, reprogramability, and robust self-healing via a brief period of thermal annealing, enabling facile fabrication […]
Tiny, wireless antennas use light to monitor cellular communication
MIT News December 20, 2024 Monitoring electrical potentials in liquid is critical in biosensing but limitations in spatial resolution and recording density remain. A team of researchers in the US (MIT, industry) introduced organic electro-scattering antennas (OCEANs) for wireless, light-based probing of electrical signals with micrometer spatial resolution, potentially from thousands of sites. The technology relied on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate light scattering properties to its doping level. Signal-to-noise ratios up to 48 were achieved in response to 100-mV stimuli. OCEANs demonstrated millisecond time constants and long-term stability, enabled continuous recordings over 10 hours. According to the researchers their work potentially accelerates […]
Model suggests Earth’s subsurface may hold up to 5.6 × 10⁶ million metric tons of natural hydrogen
Phys.org December 16, 2024 Geologic hydrogen could be a low-carbon primary energy resource; however, the magnitude of Earth’s subsurface hydrogen has not yet been assessed. Researchers at the US Geological Survey combined information from geologic analogs to construct a mass balance model to predict resource potential. Stochastic model results predicted a wide range of values for the potential in-place hydrogen resource with the most probable value of ~5.6 × 106 Mt. Although most of this hydrogen was likely to be impractical to recover, a small fraction (e.g., 1 × 105 Mt) would supply the projected hydrogen needed to reach net-zero […]
Tiny particle, huge potential: Scientists discover new type of quasiparticle present in all magnetic materials
Phys.org December 17, 2024 When the geometrical size of a nanomagnetic system is constricted to the limiting domain wall length scale, the competing energetics between anisotropy, exchange, and dipolar interactions can cause emergent kinetics due to quasiparticle relaxation, like bulk magnets of atomic origin. A team of researchers in the US (Columbia University, Oak Ridge National Laboratory) conducted an experimental and theoretical study to support that constricted nanomagnets, made of antiferromagnetic and paramagnetic neodymium thin film with honeycomb motif, revealed fast kinetic events at picosecond timescales due to the relaxation of topological quasiparticles that persisted to low temperature in the […]
A new catalyst can turn methane into something useful
MIT News December 4, 2024 Anthropogenic methane emissions, particularly from diffuse and dilute sources, pose a significant challenge for oxidation and valorization as existing methane oxidation routes rely on high temperatures or pressures. Researchers at MIT found that the catalytic coupling of alcohol oxidase with the iron-modified ZSM-5 (Fe-ZSM-5) zeolite catalyst, created a tandem methanotrophic system that partially oxidized methane at ambient temperatures and pressures. They showed that methane-to-formaldehyde selectivity could exceed 90% at room temperature. The generated formaldehyde was rapidly incorporated into a growing urea polymer. According to the researchers their work presents a sustainable route for methane oxidation… […]
Rethinking the quantum chip: Engineers present new design for superconducting quantum processor
Phys.org December 10, 2024 Qubit connectivity on a planar surface is typically restricted to only a few neighboring qubits. Overcoming the complex multilayer packaging, external cabling, and fidelity limitations, a team of researchers in the US (University of Chicago, Argonne National Laboratory) proposed and developed a high-speed on-chip quantum processor that supported reconfigurable all-to-all coupling with a large on-off ratio. They implemented the design in a four-node quantum processor, built with a modular design comprising a wiring substrate coupled to two separate qubit-bearing substrates, each including two single-qubit nodes. Using the device they demonstrated reconfigurable controlled- gates across all qubit […]
What do we know about the economics of AI?
MIT News December 6, 2024 Researchers at MIT evaluated claims about the large macroeconomic implications of new advances in AI. So long as AI’s microeconomic effects are driven by cost savings/productivity improvements at the task level, its macroeconomic consequences will be given by Gross Domestic Product (GDP) and aggregate productivity gains can be estimated by what fraction of tasks are impacted and average task-level cost savings. Predicted TFP gains over the next 10 years could be modest. They showed theoretically that even when AI improves the productivity of low-skill workers in certain tasks it may increase rather than reduce inequality. Empirically, […]
AI fact checks can increase belief in false headlines, study finds
Phys.org December 4, 2024 Recent AI language models have shown impressive ability in fact-checking tasks, but how humans interact with fact-checking information provided by these models is unclear. Researchers at Indiana University investigated the impact of fact-checking information generated by a popular large language model (LLM) on belief in and sharing intent of political news headlines in a preregistered randomized control experiment. Although the LLM accurately identified most false headlines (90%), they found that the information did not significantly improve participants’ ability to discern headline accuracy or share accurate news. In contrast, viewing human-generated fact checks enhanced discernment in both […]
Fast-curing silicone ink opens new doors in 3D printing
Phys.org December 2, 2024 Silicone elastomers have a broad variety of applications in robotics, biomedical devices, and structural metamaterials. The extrusion-based method known as direct ink write (DIW) method is limited to manufacturing mostly planar or pseudo-3D structures, but not feasible for obtaining tall or overhanging structures, or structures comprised by thin walls. Researchers at Lawrence Livermore National Laboratory demonstrated a novel Fast Cure silicone-based ink that enabled manufacturing of complex 3D structures. The Fast Cure ink was a two-part mixture. The silicone structures were produced by inline mixing and coextrusion of a part containing a catalyst (part A) and […]