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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 ...
Synchrotron Radiation Pair Distribution Function Analysis of Gels in Cements
(MDPI, 2017)
The analysis of atomic ordering in a nanocrystalline phase with small particle sizes, below 5 nm, is intrinsically complicated because of the lack of long-range order. Furthermore, the presence of additional crystalline ...
Mix and measure - Combining in situ X-ray powder diffraction and microtomography for accurate hydrating cement studies.
(Elsevier, 2023-11-14)
It is reported an innovative methodology based on in situ MoKα1 laboratory X-ray powder diffraction (LXRPD)
and microtomography (μCT) avoiding any sample conditioning. The pastes are injected in 2.0 mm capillaries and
the ...
Quantitative disentanglement of nanocrystalline phases in cement pastes by synchrotron ptychographic X-ray tomography
(IUCr, 2019)
Mortars and concretes are ubiquitous materials with very complex hierarchical microstructures. To fully understand their main properties and to decrease their CO2 footprint, a sound description of their spatially resolved ...
Synthesis of active Belite-Alite-Ye'elimite clinker (BAY)
(2016-06-29)
Ordinary Portland cement (OPC) is an environmentally contentious material, as for every ton of OPC produced, on average, 0.97 tons of CO2 are released. Ye'elimite-rich cements are considered as eco-cements because their ...
Belite cements and their activation
(Elsevier, 2020-11)
Belite cements, BCs, containing mainly belite, alite and calcium aluminates, are currently used as low heat cements.
These binders produce high amounts of C–S–H gel and have very good durability properties which are
reviewed. ...
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 ...
4D nanoimaging of early age cement hydration.
(Springer Nature, 2023-05-08)
Despite a century of research, our understanding of cement dissolution and
precipitation processes at early ages is very limited. This is due to the lack of
methods that can image these processes with enough spatial ...
Activation of LC3 low-carbon cements by C-S-H seeding.
(2023)
Portland-based Limestone Calcined Clay Cements (LC3) are attracting a lot of the attention from scholars
and field applications due to the reduction in CO2 emissions. However, their low mechanical strengths at
early ages ...
Accuracy in cement hydration investigations: Combined X-ray microtomography and powder diffraction analyses
(2022-06)
Cements are multi-phase materials that can be well understood using a multi-technique approach. Furthermore, the hydration of cement pastes is a very complex set of processes. In this work, we focus on the accuracy of the ...