Publications associées à Opale

Phase Transformation-Induced Interfacial Debonding of Silica Inclusions in Iron

Andreas Mortensen, David Hernandez Escobar, Julie Nathalie S Gheysen, Alejandra Inés Slagter

We document that in unstressed, undeformed, samples of pure iron containing silica inclusions precipitated by melt deoxidation, the iron matrix and a small fraction of the silica inclusions are locally separated at room temperature by a void. Thermal cycli ...

Springer2023

Two-dimensional atomically bridged nanoporous silicate-based membranes for gas separation

Mostapha Dakhchoune

The synthesis of molecular-sieving two-dimensional zeolitic membranes by the assembly of crystalline building blocks without resorting to the secondary growth process is highly desirable. The precise pore size for molecular sieving, ultrathin thickness, an ...

EPFL2021

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

Heinrich Hofmann

For several decades, food-grade synthetic amorphous silica (SAS) have been used as a technological additive to reduce caking of food powders. Human exposure is thus inevitable and safety concerns are taken seriously. The toxicity of silica in general and S ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Gas-sieving zeolitic membranes fabricated by condensation of precursor nanosheets

Michele Ceriotti, Kumar Varoon Agrawal, Pascal Alexander Schouwink, Luis Francisco Villalobos Vazquez de la Parra, Mostapha Dakhchoune, Claudia Esther Avalos, Yu Han, Rocio Semino Barbaresi

The synthesis of molecular-sieving zeolitic membranes by the assembly of building blocks, avoiding the hydrothermal treatment, is highly desired to improve reproducibility and scalability. Here we report exfoliation of the sodalite precursor RUB-15 into cr ...

2020

Effect of SiO2 on co-impregnated V2O5/WO3/TiO2 catalysts for the selective catalytic reduction of NO with NH3

Oliver Kröcher, Davide Ferri, Adrian Marberger

Co-impregnation of vanadia and tungsta on titania produced highly active catalysts for the reduction of nitrogen oxides with ammonia but showed aging tendencies at temperatures around 600 degrees C. In order to preserve their low temperature activity after ...

ELSEVIER SCIENCE BV2019

Structural and microstructural studies on SiC-SiO2 ceramic composites

Ho-Yun Lee

In this study, SiC ceramic substrates were prepared with 99.5% silicon carbide powders which were came from waste silicon mud during the manufacturing process of solar cells. It is found that a SiO2 layer with 50 nm in thickness is present on the SiC surfa ...

2019

Rapid mobilization of noncrystalline U(IV) coupled with FeS oxidation

Rizlan Bernier-Latmani, Malgorzata Alicja Stylo

The reactivity of disordered, noncrystalline U(IV) species remains poorly characterized despite their prevalence in biostimulated sediments. Because of the lack of crystalline structure, noncrystalline U(IV) may be susceptible to oxidative mobilization und ...

Amer Chemical Soc2016

A Monolithic Micro-Tensile Tester for Investigating Silicon Dioxide Polymorph Micromechanics, Fabricated and Operated Using a Femtosecond Laser

Yves Bellouard, Christos Edouardos Athanasiou

Mechanical testing of materials at the microscales is challenging. It requires delicate procedures not only for producing and handling the specimen to be tested, but also for applying an accurate and controlled force. This endeavor is even more challenging ...

MDPI2015

Defects in bilayer silica and graphene: common trends in diverse hexagonal two-dimensional systems

Oleg Yazyev

By combining first-principles and classical force field calculations with aberration-corrected high-resolution transmission electron microscopy experiments, we study the morphology and energetics of point and extended defects in hexagonal bilayer silica an ...

Nature Publishing Group2013

Solvent Induced Pseudopolymorphism in a Calixarene-Based Porous Host Framework

Philip Pattison

The self-assembly properties of the proximal p-tert-butylcalix[4]dihydroquinone compound have been studied to investigate the role played by crystallization conditions in driving the formation of a previously reported cubic porous framework. In chloroform ...

American Chemical Society2010