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Phase-selective degree of hydration at setting: An in situ synchrotron diffraction study
(Elsevier, 2022-03)
Setting of Portland cements is still not well understood. Previous studies used techniques that analyse the pastes as a whole to correlate setting times with degree of hydration. Here, in-situ synchrotron X-ray diffraction ...
A comparative study of experimental configurations in synchrotron pair distribution function
(MDPI - Publisher of Open Access Journals, 2019-04-25)
The identification and quantification of amorphous components and nanocrystalline phases
with very small crystal sizes, smaller than ~3 nm, within samples containing crystalline phases is
very challenging. However, this ...
Belite hydration at high temperature and pressure by in situ synchrotron powder diffraction
(2020-10-16)
Portland cements are currently used as Oil‐Well‐Cements for the sheath between the metal casing
and the borehole. At high pressures and temperatures, the resulting C-S-H gel(s) is partly unstable
and it can react to give ...
Local structure and Ca/Si ratio in C-S-H gels from hydration of blends of tricalcium silicate and silica fume
(Elsevier, 2021-03)
At the microscale, C-S-H gels from alite, or neat Portland cements, has a Ca/Si ratio close to 1.80. At the nanoscale, C-S-H is described by a defective tobermorite structure which allows a maximum Ca/Si ratio close to ...
C-S-H seeding activation of Portland and Belite cements: An enlightening in situ synchrotron powder diffraction study
(Elsevier, 2022-11)
C-S-H seeding in Portland cements is well known from basic scientific works and field applications. Moreover, this activation approach could be beneficial for low-CO2 cements under development where a general drawback is ...
Early hydration study of standard and doped Alite-Belite-Ye’elimite (ABY) cements through Synchrotron Radiation
(2018-07-09)
The manufacturing of ye'elimite-rich cements releases from 15 to 37%, depending on their
composition, less CO2 to the atmosphere than ordinary Portland cement (OPC). BYF cements
containing belite, ye’elimite and ferrite ...
Early hydration of belite-ye’elimite-ferrite cements: Role of admixtures
(sciencedirect, 2023)
The effect of TIPA and CaCl2 on early hydration, i.e. 24 h, of a B-BYF cement has been studied by in situ synchrotron X-ray powder diffraction, calorimetry, thermal analysis, NMR, and rheological measurements of the pastes ...
Rietveld quantitative phase analysis with molybdenum radiation
(Cambridge Core, 2014)
Building materials are very complex samples of worldwide importance; hence quantitative knowledge
of their mineralogical composition is necessary to predict performances. Rietveld quantitative phase
analysis (RQPA) allows ...
Applications of synchrotron x-ray powder diffraction in hydrated cements: high-resolution and high-pressure studies
(2016-07-12)
The main aim of this study is to apply synchrotron radiation techniques for the study of hydrated cement pastes. In particular, the tetracalcium aluminoferrite phase, C4AF in cement nomenclature, is the major iron-containing ...
Ptychographic X-ray computed tomography analysis of cement pastes
(2019-10-04)
Ptychographic X-ray computed tomography provides 3D electron mass density and attenuationcoefficient distributions of unaltered cement pastes with an isotropic resolution below 100 nm. Thisimaging technique allows ...