Publications associées à Drying front and water content dynamics during evaporation from sand delineated by neutron radiography

Design and assessment of an evaporating water-cooled methanation reactor for a SOE-based power-to-methane system

The transition towards clean renewable energy sources, where wind and solar are prone to variation, requires adequate energy storage. Power-to-methane (PtM) systems can be part of the solution. Specifically, solid-oxide-electrolyser (SOE) based PtM systems ...

EPFL2024

Ion Spectroscopy Reveals Structural Difference for Proteins Microhydrated by Retention and Condensation of Water

Oleg Boyarkine, Andrei Zviagin

Protein ubiquitin in its +7 charge state microhydrated by 5 and 10 water molecules has been interrogated in the gas phase by cold ion UV/IR spectroscopy. The complexes were formed either by condensing water onto the unfolded bare proteins in a temperature- ...

Amer Chemical Soc2024

Salt Bridge Structure of Microhydrated Arginine Kinetically Trapped in the Gas Phase by Evaporative Cooling

Oleg Boyarkine, Andrei Zviagin

Aminoacids and peptides generally exhibit zwitterionic forms withsalt bridge (SB) structures in solution but charge-solvated (CS) motifsin the gas phase. Here, we report a study of non-covalent complexesof the protonated amino acid arginine, ArgH(+)(H2O)( ...

2023

Bridging Native and Intrinsic Structures of Microhydrated Biomolecules by Cold Ion Spectroscopy

Andrei Zviagin

Solving native structures of such large molecules, like biomolecules, is often challenging, particularly due to the potentially infinite number of non-covalent interactions with water. In this thesis, we report the use of cold ion gas-phase action spectros ...

EPFL2023

Conductive Heat Transfer in Partially Saturated Gas Diffusion Layers with Evaporative Cooling

Sophia Haussener, Mirco Magnini, Felix N. Büchi

Heat transport is an important, though often neglected function of gas diffusion layers (GDLs) of polymer electrolyte membrane fuel cells. Thermal conductivity is a key property, especially in partially water saturated GDLs and when the phase change of wat ...

2022

The Role of Hydraulic Failure in a Massive Mangrove Die-Off Event

Alice Jacqueline Frédérique Gauthey

Between late 2015 and early 2016, more than 7,000 ha of mangrove forest died along the coastline of the Gulf of Carpentaria, in northern Australia. This massive die-off was preceded by a strong 2015/2016 El Nino event, resulting in lower precipitation, a d ...

FRONTIERS MEDIA SA2022

Molecular dynamics simulations of the evaporation of hydrated ions from aqueous solution

Philip Robin Loche

Although important for atmospheric processes and gas-phase catalysis, very little is known about the hydration state of ions in the vapor phase. Here we study the evaporation energetics and kinetics of a chloride ion from liquid water by molecular dynamics ...

NATURE PORTFOLIO2022

Seasonality of density currents induced by differential cooling

Alfred Johny Wüest, Damien Bouffard, Tomy Doda, Hugo Nicolás Ulloa Sánchez

When lakes experience surface cooling, the shallow littoral region cools faster than the deep pelagic waters. The lateral density gradient resulting from this differential cooling can trigger a cold downslope density current that intrudes at the base of th ...

2022

Mass transport of water vapor and ions from Å-scale graphene nanopores

Wan-Chi Lee

Hydrodynamics at the nanoscale involves both fundamental study and application of fluid and mass transport phenomena in nanometer-sized confinements. Nanopores in single-layer graphene can be highly attractive for exploring the molecular transport of gas a ...

EPFL2022

Convective regimes induced by surface cooling and topography in stratified waterbodies

Damien Bouffard, Tomy Doda, Hugo Nicolás Ulloa Sánchez, Cintia Luz Ramon Casanas

Gravitational convection plays a significant role in the ventilation, heat and mass distribution of aquatic systems. This study investigates thermally driven convection resulting from heat loss at the air-water interface during cooling periods in freshwate ...

Iahr-Int Assoc Hydro-Environment Engineering Research2022

80 K cryogenic stage for ice lithography

Danick Briand, Rubaiyet Iftekharul Haque, Jaemin Kim

We present a cryogenic system design and development for ice lithography. The cryo-stage is designed with embedded channels to allow direct liquid nitrogen flow, enabling fast cryogenic cooling, and low sample temperature. The stage cools down to 78.8 K in ...

ELSEVIER2022

Near-junction microfluidic cooling for high power-density GaN-on-Si electronics: A wafer, device, packaging, and system-level investigation

Remco Franciscus Peter van Erp

Electrification of the energy section, from generation to end-use, plays an essential role in reducing global CO2 emission. Innovations in power electronics are required to increase conversion efficiency and power density. Gallium nitride (GaN) transistors ...

EPFL2022

Two novel cogeneration charging stations for electric vehicles: Energy, exergy, economic, environment, and dynamic characterizations

Jan Van Herle, Hossein Pourrahmani, Chengzhang Xu

This paper suggests two novel designs for the electric vehicle charging stations using LiMn2O4 Lithium-ion battery and based on a Solid Oxide Fuel Cell (SOFC) and absorption refrigeration cycle (ARC) technologies to provide electricity and cooling, respect ...

Elsevier2022

Flow Boiling of Carbon Dioxide at Different Channel Orientations for the Thermal Management of Future Detector Technologies at the High-Luminosity Large Hadron Collider at CERN

David Schmid

The global warming potential (GWP) of working fluids in thermodynamic cycles and their environmental impact have been gaining considerable attention within the recent years. The global objectives on climate protection are becoming increasingly ambitious, w ...

EPFL2022

Multiphase transport and evaporative cooling in fuel cell gas diffusion layers

Sarah van Rooij

The use of evaporative cooling in the gas diffusion layer (GDL) of polymer electrolyte fuel cells has been proposed as a simple yet impactful solution to simultaneously provide the functionality of cell cooling, thanks to the dissipation of the latent heat ...

EPFL2021

The role of air-sea fluxes for the water vapour isotope signals in the cold and warm sectors of extratropical cyclones over the Southern Ocean

Josué Etienne Gehring, Irina Gorodetskaya

Meridional atmospheric transport is an important process in the climate system and has implications for the availability of heat and moisture at high latitudes. Near-surface cold and warm temperature advection over the ocean in the context of extratropical ...

Copernicus Gesellschaft Mbh2021

Embedded Microchannel Cooling for Monolithically-integrated GaN Half-bridge ICs

Elison de Nazareth Matioli, Palliyage Srilak Nirmana Perera, Remco Franciscus Peter van Erp, Luca Nela

Efficient and compact power conversion is a key requirement to achieve sustainable electrification of our society. GaN-based power devices offer major benefits compared to their silicon counterparts in terms of efficiency and integration but suffer from se ...

IEEE2021

Planning Multi-Scale District Energy Systems with Hybrid Cooling Technologies and Decentralized Thermal Networks for Low Carbon Cities in the Tropics

Shanshan Hsieh

Energy demand for cooling of buildings is projected to drastically increase in the next decades. Urban areas in tropical Asia are expected to contribute a major share to this growing demand. These areas are characterized by a high urban density and a diver ...

EPFL2021

Operational Map And Thermal Performance Of A Thermosyphon Cooling System For Compact Servers

John Richard Thome, Jackson Braz Marcinichen, Raffaele Luca Amalfi, Filippo Cataldo

This paper advances the state-of-the-art in novel passive two-phase systems for more efficient cooling of datacenters and telecom central offices compared to the traditional air-based cooling solutions (e.g. aisle-based containment systems). The proposed p ...

AMER SOC MECHANICAL ENGINEERS2021

Thermal management of components for high energy physics experiments and space applications

Timothée Robert Sophus Frei

High-energy physics (HEP) experiments and space missions share a common challenge: thermal management in harsh environments. The severe constraints in both fields make cooling of electronic components a major design concern. This thesis aims to develop hig ...

EPFL2021