Publications associées à Silaffins in Silica Biomineralization and Biomimetic Silica Precipitation

Additive Manufacturing of Bioinspired Mineral-Based Composites

Biominerals are used by natural organisms for example as structural supports and optical sensors. They are produced from a limited number of elements and under ambient conditions. Nevertheless, they often possess excellent mechanical properties and sometim ...

EPFL2024

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

High-Density Immobilization of TCEP on Silica Beads for Efficient Disulfide Reduction and Thiol Alkylation in Peptides

Christian Heinis

Tris-(2-carboxyethyl)phosphine (TCEP) linked to agarose beads is widely used for reducing disulfide bridges in proteins and peptides. The immobilization of TCEP on beads allows efficient removal after reduction to prevent its reaction with alkylating reage ...

2023

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

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

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

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

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

Efficient Meso-Scale Modeling of Alkali-Silica-Reaction Damage in Concrete

Ali Falsafi

The alkali-silica reaction (ASR), also known as concrete cancer, is one of the most prevalent causes of concrete degradation. In this chemical reaction, amorphous silica in the aggregates reacts with alkalis in the pore solution. By absorbing water, hydrop ...

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

The effect of alkali hydroxides and equilibration time on Al uptake by calcium silicate hydrates (C-S-H)

Sonya Barzgar

Cement production accounts for approximately 8% of man-made CO2 emissions. Lowering these CO2 emissions is currently one of the most important and urgent research topics within the cement community. To reduce these emissions, the Portland cement (PC) is pa ...

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

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

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

A modern scleractinian coral with a two-component calcite–aragonite skeleton

Anders Meibom, Jaroslaw Hubert Stolarski

One of the most conserved traits in the evolution of biomineralizing organisms is the taxon-specific selection of skeletal minerals. All modern scleractinian corals are thought to produce skeletons exclusively of the calcium-carbonate polymorph aragonite. ...

2021

Structural description of surfaces and interfaces in biominerals by DNP SENS

David Benjamin Roger Antoine Gajan, David Lyndon Emsley

Biological mineralized tissues are hybrid materials with complex hierarchical architecture composed of biominerals often embedded in an organic matrix. The atomic-scale comprehension of surfaces and organo-mineral interfaces of these biominerals is of para ...

ACADEMIC PRESS INC ELSEVIER SCIENCE2019

From the product to the process: Fine-scale skeletal structures of scleractinian corals and their relevance to biomineralization models, geochemical sampling strategies, and phylogenetic reconstructions

Anders Meibom, Jaroslaw Hubert Stolarski

Interpretation of biomineralization processes based solely on the end product - the skeleton - may seem abreakneck task. This is because the biologically controlled mineralization involves cascades of intermediatephases and the activity of a myriad of orga ...

2019

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

Biogenic non-crystalline U(IV) revealed as major component in uranium ore deposits

Rizlan Bernier-Latmani

Historically, it is believed that crystalline uraninite, produced via the abiotic reduction of hexavalent uranium (U-(VI)) is the dominant reduced U species formed in low-temperature uranium roll-front ore deposits. Here we show that non-crystalline U-(IV) ...

Nature Publishing Group2017