Exploring just how extreme future storms could get

Phys.org   September 18, 2023 Due to the lack of long homogenous climate data and methodological frameworks, it is challenging to estimate how extreme precipitation could get and what the physical drivers are. Researchers in Switzerland developed two complementary strategies to extrapolate beyond the precipitation records: (a) statistical estimates based on fitting generalized extreme value distributions, providing their probabilistic information on return periods and, (b) ensemble boosting, a model-based re-initialization of heavy precipitation in large ensembles, providing a physical coherent storyline in space and time, however, with no direct quantification of its probability. Both show that 3-day accumulated precipitation maxima can […]

Thin-film batteries rechargeable in just one minute

Science Daily  August 29, 2023 The power capability of Li-ion batteries has become increasingly limiting for the electrification of transport on land and in the air. The specific power of Li-ion batteries is restricted due to the required cathode thickness of a few tens of micrometers. Researchers in Switzerland have developed a design of monolithically stacked thin-film cells that had the potential to increase the power ten-fold. They demonstrated an experimental proof-of-concept consisting of two monolithically stacked thin-film cells. Each cell consisted of a silicon anode, a solid-oxide electrolyte, and a lithium cobalt oxide cathode. The battery could be cycled […]

Chromium replaces rare and expensive noble metals

Science Daily  August 14, 2023 Researchers in Switzerland developed chromium compounds, very similar to those used in the past, that can replace the noble metals osmium and ruthenium. When irradiated with a red lamp the new chromium compounds the energy from the light could be stored in molecules which could serve as power source. They demonstrated it by building the chromium compounds into a stiff organic molecular framework consisting of carbon, nitrogen, and hydrogen. The stiff framework ensured that the chromium atoms were well packaged. The tailor-made environment minimized energy losses due to undesired molecular vibrations and to optimize the […]

New technique measures structured light in a single shot

Phys.org  August 8, 2023 Orbital angular momentum (OAM) spectrum diagnosis is a fundamental building block for diverse OAM-based systems. Among others, the simple on-axis interferometric measurement can retrieve the amplitude and phase information of complex OAM spectra in a few shots. Yet, its single-shot retrieval remains elusive, due to the signal–signal beat interference inherent in the measurement. Researchers in Switzerland have introduced the concept of Kramers–Kronig (KK) receiver in coherent communications to the OAM domain, enabling rigorous, single-shot OAM spectrum measurement. They explained in detail the working principle and the requirement of the KK method and applied the technique to […]

Scientists improve the accuracy of weather and climate models

Phys.org  March 1, 2023 Researchers in Switzerland have developed a new modelling framework for atmospheric flow simulations for cryospheric regions called CRYOWRF. CRYOWRF couples the state-of-the-art and used atmospheric model WRF (the Weather Research and Forecasting model) with the detailed snow cover model SNOWPACK. CRYOWRF makes it feasible to simulate the dynamics of a large number of snow layers governed by grain-scale prognostic variables with online coupling to the atmosphere for multiscale simulations from the synoptic to the turbulent scales. They also introduced a scheme for blowing snow in CRYOWRF. They described the technical design goals, model capabilities and the […]

New technology revolutionizes the analysis of old ice

Science Daily  February 16, 2023 The objective of EPICA [European Project for Ice Coring in Antarctica] is to look back 1.5 million years into the past and obtain data on the development of temperature, the composition of the atmosphere and the carbon cycle. A depth of around 2700 meters must be reached in the Antarctic ice sheet and an ice core recovered which they plan to accomplish by 2025. In the 1.5-million-year-old ice, 15,000 to 20,000 years of climate history are compressed into just one meter of ice core, which places completely new demands on ice core analyzes. Researchers in […]

Solids that are also liquids: Elastic tensors of superionic material

Phys.org  January 30, 2023 Superionics display both solid- and liquid-like characteristics: as solids, they respond elastically to shear stress; as liquids, they display fast-ion diffusion at normal conditions. They are technologically relevant for energy, electronics, and sensing applications. Characterizing and understanding their elastic properties are needed to address their feasibility as solid-state electrolytes in all-solid-state batteries. However, static approaches to elasticity assume well-defined reference positions around which atoms vibrate, in contrast with the quasi-liquid motion of the mobile ions in fast ionic conductors. Researchers in Switzerland have derived the elastic tensors of superionics from ensemble fluctuations in the isobaric-isothermal ensemble, exploiting extensive Car-Parrinello simulations. They applied this approach to […]

A quantum pump without a crank

Phys.org  August 22, 2022 The pumping process can have topological origins, when considering the motion of quantum particles in spatially and temporally periodic potentials. However, the periodic evolution that drives these pumps has always been assumed to be imparted from outside. Researchers in Switzerland found an emergent mechanism for pumping in a quantum gas coupled to an optical resonator, where they observed a particle current without applying a periodic drive. The pumping potential experienced by the atoms is formed by the self-consistent cavity field interfering with the static laser field driving the atoms. The cavity field evolves between its two […]

A paper battery with water switch

Nanowerk  July 29, 2022 Researchers in Switzerland have developed a disposable paper battery aiming to reduce the environmental impact of single-use electronics for applications such as point of care diagnosis, smart packaging, and environmental sensing. The battery uses Zinc as a biodegradable metal anode, graphite as a nontoxic cathode material and paper as a biodegradable substrate. To facilitate additive manufacturing, they developed electrodes and current collector inks that can be stencil printed on paper to create water-activated batteries of arbitrary shape and size. The battery remains inactive until water is provided and absorbed by the paper substrate, taking advantage of […]

Light amplification accelerates chemical reactions in aerosols

Science Daily  April 14, 2022 Researchers in Switzerland reported that optical confinement could create spatial structuring of the light intensity inside the particle and thereby cause corresponding variations of photochemical rates. They probed single iron(III)–citrate particles using the iron oxidation state as a photochemical marker. Based on the results, they predicted an overall acceleration of photochemical reactions by a factor of two to three for most classes of atmospheric aerosol particles. Rotation of free aerosol particles and intraparticle molecular transport generally accelerate the photochemistry. According to the researchers, given the prevalence of optical confinement effects, their influence on aerosol particle […]