QICM - Artículos
Envíos recientes
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Alite-belite-ye'elimite cements: Effect of dopants on the clinker phase composition and properties
(2018-10-30)Clinkers with alite-belite-ye'elimite (ABY) are considered as eco-friendly cements. Clinkering (2 Kg) of two types of ABY clinkers was optimized: standard-ABY, with CaF2 and ZnO as dopants (32.6 wt% alite, 30.4 wt% β-C2S ... -
Influence of fly ash blending on hydration and physical behavior of Belite-Alite-Ye'elimite cements
(2018-10-19)A cement powder, composed of belite, alite and ye’elimite, was blended with 0, 15 and 30 wt% of fly ash and the resulting lended cements were further characterized. During hydration, the presence of fly ash caused the ... -
Synchrotron Pair Distribution Function analyses of Ye’elimite-based pastes
(2018-10-15)The study of nanocrystalline phase atomic ordering is intrinsically complicated. The presence of additional crystalline phase(s) exacerbates this challenge. Here, we use the synchrotron pair distribution function (PDF) to ... -
Rietveld quantitative phase analyses of SRM 2686a: a standard Portland clinker
(2018-10-03)SRM 2686a is a NIST reference Portland clinker with reported mineralogical analysis from powder diffraction and electron microscopy. This sample is used in ASTM C1365 test method for Rietveld quantitative phase analysis ... -
Assessment of the quantitative accuracy of Rietveld/XRD analysis of crystalline and amorphous phases in fly ash
(2017)An internal standard method based on Rietveld/XRD whole-pattern fitting analysis of fly ash is used to assess the quantitative accuracy to determine its crystalline and amorphous phases under various conditions such as ... -
Multiscale understanding of tricalcium silicate hydration reactions
(Nature Publishing Group, 2018-06)Tricalcium silicate, the main constituent of Portland cement, hydrates to produce crystalline calcium hydroxide and calcium-silicate-hydrates (C-S-H) nanocrystalline gel. This hydration reaction is poorly understood at ... -
X-ray diffraction, cements and environment, three worlds in one
(2017-12-13)This keynote lecture will be focused on the strategies for reducing CO2 emissions in the cement production. Concretely, the production of ecocements with optimised formulations that yield reductions in CO2 emissions of up ... -
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 ... -
Structure, Atomistic Simulations, and Phase Transition of Stoichiometric Yeelimite
(ACS publications, 2013)ABSTRACT: Yeelimite, Ca4[Al6O12]SO4, is outstanding as an aluminate sodalite, being the framework of these type of materials flexible and dependent on ion sizes and anion ordering/disordering. On the other hand, yeelimite ... -
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 ... -
Hydration mechanisms of two polymorphs of synthetic ye'elimite
(Elsevier, 2014-05-26)Ye'elimite is the main phase in calcium sulfoaluminate cements and also a key phase in sulfobelite cements. However, its hydrationmechanismis not well understood. Here we reported newdata on the hydration behavior of ... -
Hydration of C4AF in the presence of other phases: A synchrotron X-ray powder diffraction study
(Elsevier, 2015)Hydration behaviour of C4AF in selected experimental conditions has been determined. C4AF has been hydrated in the absence and presence of gypsum, two polymorphs of ye’elimite and different water/solid ratios. C4AF in ... -
Pseudo-cubic crystal structure and phase transition in doped ye'elimite
(ACS publications, 2014)Sodalites are tridimensional alumino-silicate materials containing cages where loosely bonded anions are located. Ye'elimite, Ca4[Al6O12]SO4, is outstanding as an aluminate sodalite with a flexible framework accepting ... -
Rietveld Quantitative Phase Analysis of OPC Clinkers, Cements and Hydration Products
(Mineralogical Society of America, 2012) -
Rietveld quantitative phase analysis of yeelimite-containing cements
(Karen Scrivener, 2012)Yeelimite-containing cements are attracting attention for their tailored properties. Calcium sulfoaluminate, CSA, cements have high contents of Yeelimite and they are used for special applications. Belite calcium sulfoaluminate, ... -
In-situ early-age hydration study of sulfobelite cements by synchrotron powder diffraction
(Karen Scrivener, 2014)Eco-friendly belite calcium sulfoaluminate (BCSA) cement hydration behavior is not yet well understood. Here,we report an in-situ synchrotron X-ray powder diffraction study for the first hours of hydration of BCSA ... -
Effect of calcium sulfate source on the hydration of calcium sulfoaluminate eco-cement
(2014)The availability of cements, including eco-cements, with tailored mechanical properties is very important for special applications in the building industry. Here we report a full study of the hydration of calcium sulfoaluminate ... -
Hydration Reactions and Mechanical Strength Developments of Iron- Rich Sulfobelite Eco-cements
(2013)Belite calcium sulfoaluminate (BCSA) cements are low-CO2 building materials. However, their hydration behavior and its effect on mechanical properties have still to be clarified. Here, we report a full multitechnique study ... -
Amorphous determination in calcium sulfoaluminate materials by external and internal methods
(ICE Publishing, 2014)External standard methodology has been successfully applied to quantify the known amounts of amorphous component that are increasingly added to cement-related materials. The consistency and accuracy of the methodology were ... -
Aluminum Hydroxide Gel Characterization within a Calcium Aluminate Cement Paste by Combined Pair Distribution Function and Rietveld Analyses
(Elsevier, 2017-06)There are many commercially important multiphase materials which contain amorphous phases, such as cement pastes, porcelains, glass-ceramics or pharmaceutical compounds. However, the analysis of amorphous phase(s) within ...