Publications associées à Clathrate structure-type recognition: Application to hydrate nucleation and crystallisation

Large-cage occupation and quantum dynamics of hydrogen molecules in sII clathrate hydrates

Richard Gaal, Livia Eleonora Bove Kado, Umbertoluca Ranieri

Hydrogen clathrate hydrates are ice-like crystalline substances in which hydrogen molecules are trapped inside polyhedral cages formed by the water molecules. Small cages can host only a single H-2 molecule, while each large cage can be occupied by up to f ...

Aip Publishing2024

Growth and investigation of Argon thin films adsorbed on graphite by means of Ultrafast Electron Diffraction

Paolo Usai

Starting from our big universe to the microscopic world, phase transitions play an important role in nature. Just after the Big Bang our universe experienced multiple phase transitions, from high-temperature plasma to the matter we know today. Phase transi ...

EPFL2023

Advances in hydration and thermodynamics of cementitious systems

Patrick Juilland, Karen Scrivener, Aslam Kunhi Mohamed, Thomas Matschei, Fabien Jacques Michel Georget

Optimising the hydration of cementitious materials is crucial to leverage their full potential and avoid wasting resources, embodied energy and CO2. Understanding the fundamental mechanisms is key to reach these objectives. In this paper, we review progres ...

Pergamon-Elsevier Science Ltd2023

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

Microbial-induced carbonate precipitation applicability with the methane hydrate-bearing layer microbe

Alexandra Clarà Saracho

Production of methane gas from the methane-hydrate-bearing layer below the deep-ocean floor is expected to be crucial in the future of energy resources worldwide. During the methane gas-production phase from the methane hydrate with the depressurisation me ...

ELSEVIER SCI LTD2020

Using High-Temporal-Resolution Ambient Data to Investigate Gas-Particle Partitioning of Ammonium over Different Seasons

Yan Feng, Athanasios Nenes, Qianyu Zhao

Ammonium is one of the dominant inorganic water-soluble ions in fine particulate matter (PM2.5). In this study, source apportionment and thermodynamic equilibrium models were used to analyze the relationship between pH and the partitioning of ammonium (eps ...

AMER CHEMICAL SOC2020

Inexpensive modeling of quantum dynamics using path integral generalized Langevin equation thermostats

Michele Ceriotti, Jinggang Lan, David Mark Wilkins, Venkat Kapil

The properties of molecules and materials containing light nuclei are affected by their quantum mechanical nature. Accurate modeling of these quantum nuclear effects requires computationally demanding path integral techniques. Considerable success has been ...

2020

Observation of methane filled hexagonal ice stable up to 150 GPa

Richard Gaal, Philippe Gillet, Livia Eleonora Bove Kado, Umbertoluca Ranieri

Gas hydrates consist of hydrogen-bonded water frameworks enclosing guest gas molecules and have been the focus of intense research for almost 40 y, both for their fundamental role in the understanding of hydrophobic interactions and for gas storage and ene ...

National Academy of Sciences2019

Predicting homogeneous nucleation rate from atomistic simulations

Bingqing Cheng

Predictive modelling and quantitative understanding of nucleation is essential for predicting phase transformation processes in nature and precisely controlling material synthesis and processing. Atomistic modeling is a powerful tool for capturing the dyna ...

EPFL2019

Water Activity from Equilibrium Molecular Dynamics Simulations and Kirkwood-Buff Theory

Satoshi Takahama, Mária Lbadaoui-Darvas

Water activity and related thermodynamic properties are calculated for several aqueous solutions using equilibrium molecular dynamics in conjunction with the recent extension of the Kirkwood-Buff (KB) theory for closed systems. The general applicability of ...

AMER CHEMICAL SOC2019

Quantum Dynamics of H-2 and D-2 Confined in Hydrate Structures as a Function of Pressure and Temperature

Richard Gaal, Philippe Gillet, Livia Eleonora Bove Kado, Umbertoluca Ranieri

We present an extensive study of the quantum dynamics of molecular hydrogen trapped within the nanocavities of two hydrate structures at low temperatures, namely, clathrate structure II and filled ice structure Cl. By inelastic neutron scattering measureme ...

AMER CHEMICAL SOC2019

Guest dynamics in methane hydrates and hydrogen hydrates under high pressure

Umbertoluca Ranieri

Hydrates of gas are non-stoichiometric inclusion compounds constituted of water and gas. Therein, the water molecules are hydrogen-bonded and form three-dimensional crystalline networks incorporating different kinds of polar or nonpolar guest gas molecules ...

EPFL2018

The underappreciated role of nonvolatile cations in aerosol ammonium-sulfate molar ratios

Hairun Guo, Athanasios Nenes

Overprediction of fine-particle ammonium-sulfate molar ratios (R) by thermodynamic models is suggested as evidence for interactions with organic constituents that inhibit the equilibration of gas-phase ammonia with aerosol sulfate and questions the equilib ...

Copernicus Publications2018

Flat-Histogram Monte Carlo as an Efficient Tool To Evaluate Adsorption Processes Involving Rigid and Deformable Molecules

Berend Smit, Matthew David Witman

Monte Carlo simulations are the foundational technique for predicting thermodynamic properties of open systems where the process of interest involves the exchange of particles. Thus, they have been used extensively to computationally evaluate the adsorptio ...

2018

Thermodynamic-Kinetic Precipitation Modeling. A Case Study: The Amorphous Calcium Carbonate (ACC) Precipitation Pathway Unravelled

Paul Bowen, Andrea Testino, Christian Ludwig, Frank Pilger, Agnese Carino, Mohammad Reza Andalibi

Nine accurate experimental data sets on amorphous calcium carbonate (ACC) formation in dilute solution were collected varying temperature and pH. The entire precipitation process is described using a complete thermodynamic-kinetic model. The thermodynamic ...

American Chemical Society2017

Surface Reactions are Crucial for Energy Storage

Andreas Züttel, Shunsuke Kato, Elsa Callini, Philippe Mauron

Reactions between gas molecules, e.g. H-2 and CO2 and solids take place at the surface. The electronic states and the local geometry of the atomic arrangement determine the energy of the adsorbate, i.e. the initial molecule and the transition state. Here w ...

Schweizerische Chemische Gesellschaft2015

Methane Clathrate Hydrate Nucleation Mechanism by Advanced Molecular Simulations

Simone Meloni

The nucleation mechanisms of methane hydrates are studied using well-tempered metadynamics and restrained molecular dynamics. The collective variables we used to follow the process are the methane-methane and methane-water coordination numbers, from which ...

Amer Chemical Soc2014

The role of thermodynamics in biochemical engineering

Urs von Stockar

This article is an adapted version of the introductory chapter of a book whose publication is imminent. It bears the title "Biothermodynamics - The role of thermodynamics in biochemical engineering." The aim of the paper is to give a very short overview of ...

De Gruyter2013

Summer methane fluxes from a boreal bog in northern Quebec, Canada, using eddy covariance measurements

Marc Parlange, Daniel Nadeau

A boreal bog located in the James Bay lowlands, Canada, was instrumented with an open-path gas analyzer to monitor the turbulent fluxes of methane throughout the summer of 2012. The mostly continuous eddy covariance measurements permitted the study of meth ...

Elsevier2013

Fe-containing Hydrates and their Fate during Cement Hydration : Thermodynamic Data and Experimental Study

Belay Zeleke Dilnesa

Thermodynamic modeling is a versatile tool for predicting the chemical composition cement during the hydration of cement. The quality of the thermodynamic modeling depends directly on the quality and completeness of thermodynamic database used. One of the ...

EPFL2012