Science Daily January 5, 2022 Topological materials are promising for transistors. However, it is difficult to turn off the dissipationless flow of electrons in topological materials. A team of researchers in the US (Harvard University, Wellesley College) has numerically demonstrated a topological logic gate for ultrasound by exploiting the large phase space of accidental degeneracies in a honeycomb lattice. They found that a degeneracy can be broken by six physical parameters and showed how to tune these parameters to create a phononic switch that transitions between a topological waveguide and a trivial insulator by ultrasonic heating. According to the researchers, […]
How Long Do Black Carbon Particles Linger in the Atmosphere?
SciTech Daily January 1, 2022 In previous studies, the cloud nucleation values of black carbon were indirect measurements. An international team of researchers (UK, China) concurrently measured the concentration of cloud condensation nuclei and black carbon particles near heavily trafficked roads and industrial centers in Wuhan, China. They found that the activation diameter, or the size of the black carbon particle where half of the particles will nucleate and precipitate out, was 144 ± 21 nanometers at 0.2% supersaturation. How these black carbon–containing particles could act as cloud nuclei is determined by their size combined with their coatings, the authors say, […]
Iodine in Desert Dust Destroys Ozone – Could Prolong Greenhouse Gas Lifetimes
SciTech Daily December 31, 2021 An international team of researchers (USA – University of Colorado, NCAR, industry, University of Wisconsin, NESDIS, Spain, Argentina) has shown that dust is a source of gas-phase iodine, indicated by aircraft observations of iodine monoxide (IO) radicals inside lofted dust layers from the Atacama and Sechura Deserts that are up to a factor of 10 enhanced over background. Gas-phase iodine photochemistry, commensurate with observed IO, is needed to explain the low O3 inside these dust layers (below 15 ppbv; up to 75% depleted). The added dust iodine can explain decreases in O3 of 8% regionally […]
A-list candidate for fault-free quantum computing delivers surprise
Science Daily December 22, 2021 Spin-triplet pairing is important because it can host topological states and majorana fermions relevant for quantum computation. Because spin-triplet pairing is usually mediated by ferromagnetic (FM) spin fluctuations, uranium-based materials near an FM instability are ideal candidates for realizing spin-triplet superconductivity. UTe2 has been identified as a candidate for a chiral spin-triplet topological superconductor near an FM instability, although it also has antiferromagnetic (AF) spin fluctuations. A team of researchers in the US (Rice University, Florida State University, Oak Ridge National Laboratory, UC San Diego, Arizona State University) used inelastic neutron scattering (INS) to show […]
Minimizing laser phase noise with machine learning
Phys.org January 3, 2022 One way of getting closer to an ultra-precise laser is to determine the phase noise and compensate for it. Researchers in Denmark have developed an algorithm that can analyze and find laser light patterns using machine learning, where a model for the noise is constantly being improved. On this basis they hope to develop a form of intelligent filter that continuously cleans the laser beam of noise. They were able to measure the noise up to very high frequencies, and the results contradicted the established understanding of laser noise. With the more detailed knowledge of the […]
New research finds way to scrub carbon dioxide from factory emissions, make useful products
Phys.org January 3, 2022 An international team of researchers (USA – Oregon State University, Columbia University, UK) has developed lanthanide based MOFs catalyst and loaded with propylene oxide to catalyze the production of cyclic carbonates while scrubbing CO2 from factory flue gases. Structural analysis of the propylene oxide (PO)loaded MOF revealed the binding of PO to Ce3+, confirming the key role of open Ce3+ sites in reducing the activation energy of the PO chemical transformation. They reported high catalytic activity toward Propylene carbonate production. The catalyst showed no catalytic deterioration after three cycles…read more. TECHNICAL ARTICLE
Revitalizing batteries by bringing ‘dead’ lithium back to life
Science Daily January 4, 2022 Because i-Li loses electrical connection with the current collector, it has been considered electrochemically inactive or ‘dead’ in batteries. A team of researchers in the US (Stanford University, SLAC National Accelerator Laboratory) showed that i-Li is highly responsive to battery operations, owing to its dynamic polarization to the electric field in the electrolyte. Simultaneous Li deposition and dissolution occurs on two ends of the i-Li, leading to its spatial progression toward the cathode (anode) during charge (discharge). Through their results they showed that the progression rate of i-Li is mainly affected by its length, orientation, […]
Safer carbon capture and storage
Science Daily December 29, 2021 From the gene-sequencing analyses of the behaviour of CO2 within a CO2-Eenhanced Oil Recovery (EOR) flooded oil field an international team of researchers (UK, USA – Woods hole Oceanographic Institution, industry, France, Canada) has shown that up to 74% of CO2 left behind by CO2-EOR was dissolved in the groundwater. It also revealed, that microbial methanogenesis converted as much as 13-19% of the injected CO2 to methane, which is a stronger greenhouse gas than CO2. The authors suggest that this process is occurring at other CO2-rich natural gas fields and CO2-EOR oil fields. Temperature is […]
Self-Detoxifying Wearable Filter for Development of Next Generation NBC Protective Gear
Global Biodefense January 2, 2022 Researchers in India have developed a highly effective self-detoxifying filter consisting of in-situ immobilized Zirconium hydroxide [Zr(OH)4] over woven activated carbon fabric [Zr(OH)4@W-ACF] for the removal of CWAs. It harnesses the synergistic effect of high surface area of the woven activated carbon fabric dispersing CWAs. The kinetics of in-situ degradation of CWAs over Zr(OH)4@W-ACF were found to be following the first-order reaction kinetics. The potential practical applicability of this work was established by fabricating Zr(OH)4@W-ACF as reactive adsorbent layer for protective suit and found to meet the specified criteria in terms of air permeability, tearing […]
Suiting up with Al-Mg-Si: New protective coating for steel in ships and marine and coastal facilities
Phys.org January 5, 2022 Improving the corrosion resistance of steel by coating it with aluminum for marine applications is limited because of chloride ions in sea water on aluminum. Researchers in South Korea fabricated alloy films with excellent corrosion resistance by depositing an Mg film on Al-Si coated steel sheets and applying heat treatment. The fabricated Al-Mg-Si alloy film formed a corrosion product film composed of two layers, showing an excellent barrier effect against corrosion factors. The Mg in the film fabricated by heat treatment for 5 min was widely distributed in a dissolved state on the AI phase and […]