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Publications associées (66)
Well-Defined Ti Surface Sites in Ziegler-Natta Pre-Catalysts from 47/49Ti Solid-State Nuclear Magnetic Resonance Spectroscopy
Treatment of Ziegler-Natta (ZN) catalysts with BCl3 improves their activity by increasing the number of active sites. Here we show how Ti-47/49 solid-state nuclear magnetic resonance (NMR) spectroscopy enables us to understand the electronic structure of t ...
Washington2024Room-temperature strength of the interfacial bond between silica inclusions and iron
Andreas Mortensen, David Hernandez Escobar, Alejandra Inés Slagter, Sergio Perosanz Amarillo
The strength of the interface between iron (Fe) and individual spherical silica (SiO2) inclusions of 5 +/- 1 mu m diameter is measured by means of in-situ micro-cantilever bending tests conducted under displacement control within a scanning electron micros ...
Oxford2023Composition and Pressure Effects on Partitioning of Ferrous Iron in Iron-Rich Lower Mantle Heterogeneities
Philippe Gillet, Marco Cantoni, James Badro, Susannah McGregor Dorfman, Farhang Nabiei, Charles-Edouard Boukaré
Both seismic observations of dense low shear velocity regions and models of magma ocean crystallization and mantle dynamics support enrichment of iron in Earth’s lowermost mantle. Physical properties of iron-rich lower mantle heterogeneities in the modern ...
2021The effect of alkali hydroxides and equilibration time on Al uptake by calcium silicate hydrates (C-S-H)
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 ...
EPFL2021Efficacy of SCMs to mitigate ASR in systems with higher alkali contents assessed by pore solution method
Karen Scrivener, Lionel Sofia, Marie Joshua Tapas
This study demonstrates the efficacy of supplementary cementitious materials (SCMs) to mitigate alkali-silica reaction (ASR) even when used in conjunction with cement of higher alkali contents (up to 1% Na2Oeq). The expansion of concrete prisms was studied ...
PERGAMON-ELSEVIER SCIENCE LTD2021Dissolved major and trace geochemical dynamics in Antarctic lacustrine systems
Clearwater Mesa Uames Ross Island, northeast Antarctic Peninsula) provides a unique opportunity to study solute dynamics and geochemical weathering in the pristine lacustrine systems of a high latitude environment. In order to determine major controls on t ...
2020Effects of composition and pressure on electronic states of iron in bridgmanite
Arnaud Magrez, Philippe Gillet, Susannah McGregor Dorfman
Electronic states of iron in the lower mantle's dominant mineral, (Mg,Fe,Al)(Fe,Al,Si)O-3 bridgmanite, control physical properties of the mantle including density, elasticity, and electrical and thermal conductivity. However, the determination of electroni ...
MINERALOGICAL SOC AMER2020Mn4+-Substituted Li-Rich Li1.2Mn0.43+Mnx4+Ti0.4-xO2 Materials with High Energy Density
In this work, Li-rich Li1.2Mn0.43+Mnx4+Ti0.4-xO2 (LMMxTO, 0
2020Deciphering Iron-Dependent Activity in Oxygen Evolution Catalyzed by Nickel-Iron Layered Double Hydroxide
Xile Hu, Lichen Bai, Seunghwa Lee
Nickel iron oxyhydroxide is the benchmark catalyst for the oxygen evolution reaction (OER) in alkaline medium. Whereas the presence of Fe ions is essential to the high activity, the functions of Fe are currently under debate. Using oxygen isotope labeling ...
WILEY-V C H VERLAG GMBH2020Cracks, porosity and microstructure of Ti modified polymer-derived SiOC revealed by absorption-, XRD- and XRF-contrast 2D and 3D imaging
Jürgen Brugger, Helena Van Swygenhoven, Nicola Casati, Lorenz Hagelüken
Morphology, phase composition, cracks and porosity are investigated in monolithic Ti modified SiOC polymer-derived ceramics pyrolyzed at 1000°C and 1400°C using synchrotron X-ray full field absorption- contrast tomographic microscopy and scanning XRF- and ...
2020