Publications associées à The impact of synthetic amorphous silica (E 551) on differentiated Caco-2 cells, a model for the human intestinal epithelium

Modulating the Surface Properties of Lithium Niobate Nanoparticles by Multifunctional Coatings Using Water-in-Oil Microemulsions

Sandrine Gerber, Adrian Stefan Gheata, Manon Inès Noëlla Wittwer, Alessandra Spada

Inorganic nanoparticles (NPs) have emerged as promising tools in biomedical applications, owing to their inherent physicochemical properties and their ease of functionalization. In all potential applications, the surface functionalization strategy is a key ...

2023

Wetting Dynamics Beneath an Impacting Droplet

Ramin Kaviani

Many natural and industrial processes involve fluid flow at a three phase interface between liquid, solid and gas. When the liquid is forced to move rapidly over the solid surface, the physical mechanisms governing contact line motions are multi-phase and ...

EPFL2023

Effect of different ions on dissolution rates of silica and feldspars at high pH

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri, Mahdieh Shakoorioskooie

The dissolution kinetics of silica-containing minerals in aggregates influences strongly the process of ASR in concrete. In this paper, the effect of different ions on the dissolution rates of SiO2 (amorphous and quartz) and feldspars at high pH values was ...

Pergamon-Elsevier Science Ltd2022

Abnormal temperature dependent elastic properties of fused silica irradiated by ultrafast lasers

Yves Bellouard, Pieter Vlugter

Materials with thermal-invariant elastic properties are of interest for resonant device frequency and dimensional stability of precision devices. Here, we demonstrate that the temperature coefficient of elasticity (TCE) of amorphous silica can be locally r ...

2022

Characterization of water sorption cycle in the cement microstructure of controlled oxide composition

Monisha Rastogi

This thesis investigates the water vapour sorption behaviour of samples with maximized calcium-silicate-hydrate (C-S-H) content. Primarily, the role of heterogeneous and homogeneous cavitation has been studied during the drying of cementitious materials. C ...

EPFL2022

Strong silicon oxide inclusions in iron

Andreas Mortensen, Léa Deillon, Alejandra Inés Slagter, Joris Pierre Everaerts

Oxide inclusions are ubiquitous in steel and are known to affect, generally in a negative sense, the mechanical performance of steel products. Micromechanical properties of those phases are therefore important, yet they have remained largely unexplored. We ...

2022

Effect of alkali hydroxide on calcium silicate hydrate (C-S-H)

Karen Scrivener, Barbara Lothenbach, Émilie Michèle L'Hôpital, Sheng-Yu Yang, Yu Yan

This paper investigates the effect of KOH and NaOH on C-S-H structure and solubility. Both KOH and NaOH have a similar effect, they increase pH values and silicon concentrations, and decrease calcium concentrations. At higher alkali hydroxide concentration ...

Pergamon-Elsevier Science Ltd2022

In Situ Monitoring of the Surface Evolution of a Silver Electrode from Polycrystalline to Well-Defined Structures

Yunchang Liang

Capturing the surface-structural dynamics of metal electrocatalysts under certain electrochemical environments is intriguingly desired for understanding the behavior of various metal-based electrocatalysts. However, in situ monitoring of the evolution of a ...

AMER CHEMICAL SOC2022

Effect of alkali, aluminium and equilibration time on calcium-silicate-hydrates

Yu Yan

Calcium silicate hydrate (C-S-H) is the main hydration product in Portland and blended cements, and greatly affects durability and mechanical properties of the hydrated cement. In the presence of Al-rich supplementary cementitious materials (SCMs), C-(A-)S ...

EPFL2022

Molecular insights into the electrical double layer of colloidal oxide particles obtained through second harmonic scattering

Marie Bischoff

Photocatalytic applications play an essential role in the search for alternative energy sources and environmental decontamination techniques. It is of fundamental interest to understand on a molecular level the aqueous solid/liquid interface, where photoca ...

EPFL2022

Grafting of Alkali Metals on Fumed Silica for the Catalytic Dehydrogenation of Methanol to Formaldehyde

Christophe Jean Baranowski, Oliver Kröcher, Alimohammad Bahmanpour, Jack Brandon

Water free, non-oxidative catalytic dehydrogenation of methanol to formaldehyde is an important process for the formation of anhydrous, molecular formaldehyde (FA). Sodium or sodium-containing salts were shown to catalyze the reaction, but their reaction m ...

Wiley-VCH Verlag2021

Aggregate dissolution in different pore solutions

Mahsa Bagheri

The occurrence of cracking due to alkali silica reaction (ASR) affects the service life of concrete structures. The dissolution of silica-containing minerals within aggregates causes the formation of ASR products, which fill macroscopic cracks and cause th ...

EPFL2021

Ultrafast carbothermal reduction of silica to silicon using a CO2 laser beam

Jaeki Jeong

We report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peak ...

NATURE RESEARCH2020

Advances in heterogeneous catalysis for the synthesis of polyoxymethylene dimethyl ethers

Christophe Jean Baranowski

Our society is engaged in a major shift towards more sustainable industries. The required transition from fossils to renewable resources with low greenhouse gas emission is specifically challenging in the transportation sector where high thermal efficiency ...

EPFL2020

Cold Atmospheric Plasma Inactivation of Microbial Spores Compared on Reference Surfaces and Powder Particles

Alan Howling, David Martinet

Heat-resistant spores on a dry, heat- and water-sensitive food matrix are difficult to inactivate. Radioactive or X-ray exposure is allowed and accepted only for some selected commodities. Non-thermal atmospheric pressure plasma treatments could offer an e ...

SPRINGER2020

Shape Engineering of Metal-Organic Frameworks via MOF@Polymer Composite Fabrication

Bardiya Valizadeh

Metal-organic frameworks (MOFs) are a fascinating class of porous materials that have become the subject of research owing to their unique characteristics such as high surface areas, low densities, and structural tunability. Recently, the research has been ...

EPFL2020

Thermal activation and aging of a V2O3/WO3-TiO2 catalyst for the selective catalytic reduction of NO with NH3

Oliver Kröcher, Adrian Marberger, Davide Ferri, Rob Jeremiah G. Nuguid

Real-world vanadium-based catalysts for the selective catalytic reduction (SCR) of NO with NH3 are occasionally exposed to high temperatures, which can induce catalyst aging. In this work, a 2.0 wt% V2O5/WO3-TiO2 catalyst based on commercial WO3-TiO2 was l ...

ELSEVIER SCIENCE BV2019

Silicon isotopes in Arctic and sub-Arctic glacial meltwaters: the role of subglacial weathering in the silicon cycle

Tyler Joe Kohler

Glacial environments play an important role in high-latitude marine nutrient cycling, potentially contributing significant fluxes of silicon (Si) to the polar oceans, either as dissolved silicon (DSi) or as dissolvable amorphous silica (ASi). Silicon is a ...

2019

Interference of engineered nanomaterials in flow cytometry: A case study

Aurélie Walter

Nanotechnology is regarded as the enabling technology of the 21st century. However, only a relatively small number of nano-enabled medical and healthcare products finally made their way to the market. There are several reasons why such innovative approache ...

ELSEVIER SCIENCE BV2018

Determining the Surface Structure of Silicated Alumina Catalysts via Isotopic Enrichment and Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy

David Lyndon Emsley, Brennan James Walder, Jasmine Viger-Gravel

Isotopic enrichment of Si-29 and DNP-enhanced NMR spectroscopy are combined to determine the detailed surface structure of a silicated alumina catalyst. The significant sensitivity enhancement provided by DNP is vital to the acquisition of multinuclear and ...

American Chemical Society2017