Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Concept

Réaction d'hydratation

Publications associées (27)

Hydration and mixture design of calcined clay blended cements: review by the RILEM TC 282-CCL

Karen Scrivener, Franco Alberto Zunino Sommariva, Mohsen Ben Haha, François Henri Avet

The RILEM technical committee 282-CCL: Calcined Clays as Supplementary Cementitious Materials, investigates all the aspects related to calcined clays, from clay exploration and characterization to calcination process, hydration reactions and concrete prope ...

SPRINGER2022

Radical Alkynylations with EthynylBenziodoXolones: From Photocatalysis to Direct Excitation

Jérôme Waser, Stephanie Grace Elizabeth Amos

Ethynylbenziodoxolones (EBXs) have recently emerged as potent reagents for the alkynylation of radicals. Their combination with photocatalysis allows the synthesis of valuable alkynes at room temperature. Herein, we discuss two photomediated strategies for ...

2022

Photocatalytic Umpolung of N- and O-substituted alkenes for the synthesis of 1,2-amino alcohols and diols

Jérôme Waser, Stefano Nicolai, Stephanie Grace Elizabeth Amos

We report an organophotocatalytic 1,2-oxyalkynylation of ene-carbamates and enol ethers using Ethynyl BenziodoXolones (EBXs). 1-Alkynyl-1,2-amino alcohols and diols were obtained in up to 89% yield. Photocatalytic formation of radical cations led to Umpolu ...

2020

Azide Radical Initiated Ring Opening of Cyclopropenes Leading to Alkenyl Nitriles and Polycyclic Aromatic Compounds

Jérôme Waser, Bastian Antoine Rodolphe Claude Muriel

We report herein a radical‐mediated amination of cyclopropenes. The transformation proceeds through a cleavage of the three‐membered ring after the addition of an azide radical on the strained double bond and leads to tetrasubstituted alkenyl nitrile deriv ...

Wiley-VCH Verlag GmbH2020

Hydration reactions and stages of clinker composed mainly of stoichiometric ye'elimite

Karen Scrivener, Mohsen Ben Haha, Emmanuelle Anne Boehm Courjault, Frank Bullerjahn

Ye'climitc (Ca4Al6O12SO4 or C(4)A(3)(S) over bar) is the main hydraulic mineral present in calcium sulfoaluminate cement (CSA). The hydration of ye'elimite is responsible for the early age cement properties. We identify 5 stages in the hydration of neat st ...

Pergamon-Elsevier Science Ltd2019

The needle model: A new model for the main hydration peak of alite

Karen Scrivener, Alexandre Reda Constantin William Caleb Ouzia

This article presents a new model for the main hydration peaks of tricalcium silicate and alite on the assumption that C-S-H nucleates and grows as needles. The model relies only on directly observable quantities and reproduces the transition from the acce ...

Pergamon-Elsevier Science Ltd2019

Impacting factors and properties of limestone calcined clay cements (LC3)

Karen Scrivener, Franco Alberto Zunino Sommariva, François Henri Avet, Julien Ston, Aurélie Rosine Favier, Hamed Maraghechi, Wilasinee Hanpongpun

This paper details the main factors influencing the performance of limestone calcined clay cements (LC3). The kaolinite content plays a major role in the rheological properties as well as strength development. Even in the presence of secondary phases, kaol ...

ICE PUBLISHING2019

Investigation of the use of Limestone Calcined Clay Cement (LC3) applied to Thailand

Wilasinee Hanpongpun

The replacement of clinker with supplementary cementitious materials (SCMs) is the most interesting solution to reduce the CO2 emissions from cement production. The abundant availability of clays, which have a sufficient amount of kaolinite content in Thai ...

EPFL2019

Rapid, Robust, and Relevant (R3) Reactivity Test for Supplementary Cementitious Materials

Karen Scrivener, François Henri Avet, Xuerun Li, Ruben Anton Snellings

Although supplementary cementitious materials (SCMs) are now commonly accepted and widely used, consensus has not been reached for methods to test their chemical reactivity. A multitude of test methods exist but often fall short on one or more of the key f ...

AMER CONCRETE INST2019

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

Philippe Gillet, Richard Gaal, 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

Characterisation and hydration of ye'elimite containing cements

Frank Bullerjahn

Calcium sulphoaluminate cements (CSA) with the main phase yeâ elimite are a promising class of non-Portland cements which are gaining increasing interest from the cement industry. However, the hydration kinetics of CSA cements varies strongly, even for ce ...

EPFL2018

Microhydration of Dibenzo-18-Crown-6 Complexes with K+, Rb+, and Cs+ Investigated by Cold UV and IR Spectroscopy in the Gas Phase

Thomas Rizzo, Yoshiya Inokuchi

In this Article, we examine the hydration structure of dibenzo-18-crown-6 (DB18C6) complexes with K+, Rb+, and Cs+ ion in the gas phase. We measure well-resolved UV photodissociation (UVPD) spectra of K+·DB18C6·(H2O)n, Rb+·DB18C6·(H2O)n, and Cs+·DB18C6·(H2 ...

2018

"Palladium-Catalyzed Diamination of Alkynes in Synthesis of Tetracycles" and "Copper-Catalyzed Cyanoalkylation of Unactivated Alkenes"

Minh Tu Ha

The thesis deals with the development of transition metal-catalyzed difunctionalization of alkenes and alkynes, which can be categorized into two major topics: (1) palladium-catalyzed diamination of alkynes for the synthesis of tetracycles; (2) copper-cata ...

EPFL2017

Orientational ordering of water in extended hydration shells of cations is ion-specific and is correlated directly with viscosity and hydration free energy

Sylvie Roke, Yixing Chen, Halil Ibrahim Okur, Chung-Wen Liang

Specific ion effects in aqueous solutions are investigated at the molecular, nanoscopic and macroscopic levels. Femtosecond elastic second harmonic scattering (fs-ESHS) is used here to assess the chemical effects of ions on molecular and nanoscopic length ...

2017

Base-Catalyzed Intramolecular Hydroamination of Cyclohexa-2,5-dienes: Insights into the Mechanism through DFT Calculations and Application to the Total Synthesis of epi-Elwesine

Kurt Schenk

The base-catalyzed intramolecular hydroamination of 1-ethylaminocyclohexa-2,5-dienes is described. The transformation proceeds through isomerization of the cyclohexa-1,4-dienyl fragment into the corresponding conjugated 1,3-diene prior to the hydroaminatio ...

Wiley-V C H Verlag Gmbh2014

Modelling Hydration Kinetics of Cementitous Systems

Aditya Kumar

The modeling platform µic has been extended to study the hydration of cement based systems. It is shown that the hydration kinetics of alite can be described through the implementation of two mechanisms: a solution controlled dissolution (SCD) mechanism fo ...

EPFL2012

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

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

Hydration of cementitious materials, present and future

Karen Scrivener

This paper is a keynote presentation from the 13th International Congress on the Chemistry of Cement. It discusses the underlying principles of hydration and recent evidence for the mechanisms governing this process in both Portland cements and other cemen ...

Pergamon-Elsevier Science Ltd2011

Hydration of C3A with Calcium Sulfate Alone and in the Presence of Calcium Silicate

Alexandra Quennoz

Tricalcium aluminate (C3A) is one of the main constituents of Portland cement. Even though it represents less than 10% of the total composition, its strong reaction with water can lead to a rapid setting, called flash set. Gypsum is added to regulate this ...

EPFL2011

Mechanisms of cement hydration

Karen Scrivener

The current state of knowledge of cement hydration mechanisms is reviewed, including the origin of the period of slow reaction in alite and cement, the nature of the acceleration period, the role of calcium sulfate in modifying the reaction rate of tricalc ...

Pergamon-Elsevier Science Ltd2010