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Water-to-cement ratio influence on low-carbon cements performances
(2019)
Portland Cement (PC) is the most important active ingredient in most of the construction concrete. However, the PC production is associated with a high carbon dioxide release (around 1 ton of CO2 per ton of PC). One approach ...
The use of mo and cu monochromatic radiations for quantitative phase analysis: study of the accuracy
(2016-06-27)
Cement hydration is a very complex process in which crystalline phases are dissolving in water and after supersaturation hydrated crystalline and amorphous phases precipitate. Great efforts are being made to develop ...
Quantitative phase Analisis: A comparative study of Mo and Cu strictly monochromatic radiations
(2016-06-27)
A comparison of the Rietveld quantitative phase analyses (RQPA) obtained using Cu-Kα1, Mo-Kα1, and synchrotron strictly monochromatic radiations is presented. The main aim is to test a simple hypothesis: high energy ...
Clinkering and early age hydration characterization of Belite-Alite Calcium Sulfoaluminate (BACSA) cements
(2015-10-26)
In this work, four BACSA clinkers with different compositions (belite ~ 70-55 wt %, alite ~ 10-15 wt % and ye’elimite ~ 10-15 wt %) were synthesized (at laboratory scale). Lime, gypsum, kaolin and sand were used as raw ...
Pair distribution function studies in cementitious systems
(2017-10-24)
The analysis of amorphous/nanocrystalline phase(s) within cement matrices that contain high amounts of crystalline phase(s) is very challenging. Synchrotron techniques can be very useful to characterize such complex samples.1 ...
Synthesis and scaled-up of non-active and active Belite-Alite-Ye'elimite clinker (BAY)
(2017-05-17)
Ordinary Portland cement (OPC) is an environmentally contentious material, as for every ton of OPC produced, ~0.97 tons of CO2 are released. This opens the need of designing new formulations of cements formed by low calcite ...
Hydration study of alite-ye’elimite-anhydrite phases associated to BAY cement
(2017-10-18)
An alternative to decrease CO2 emissions from OPC production consists on the development of a new kind of eco-cements composed by less calcite demanding phases, such as belite and ye'elimite. That is the case of ...
Effect of different retarders on the hydration of calcium sulfoaluminate eco-cement pastes
(2014-07-09)
The manufacture of Calcium SulfoAluminate (CSA) cements is more environmentally friendly than that of OPC [1] as their production releases up to 40% less CO2 than the latter. The main performances of CSA cements are fast ...
X-ray powder diffraction applied to cement related phases: in-situ and high resolution applications
(2014-07-03)
XRPD is a powerful tool for material characterization in general, and for in-situ studies of chemical processes in particular. The use of an intense X-ray source, .i.e. synchrotron X-rays, coupled with fast X-ray detection ...
Advanced synchrotron studies of ye'elimite-based cement pastes
(2018-07-18)
Synchrotron characterization techniques [1] are being used to study Portland-based cements and recently also CSA and related cements. A key property of these techniques is that they do not require sample preparation, so ...