Envíos recientes

  • Rietveld Quantitative Phase Analysis of Oil Well Cement: in Situ Hydration Study at 150 Bars and 150 °C 

    Fraga, Edmundo; Cuesta, Ana; Zea-Garcia, Jesus D.; De la Torre, Angeles G.; Yañez-Casal, Armando; [et al.] (MDPI - Publisher of Open Access Journals, 2019-06)
    Oil and gas well cements are multimineral materials that hydrate under high pressure and temperature. Their overall reactivity at early ages is studied by a number of techniques including through the use of the consistometer. ...
  • Quantitative disentanglement of nanocrystalline phases in cement pastes by synchrotron ptychographic X-ray tomography 

    Cuesta, Ana; De la Torre, Angeles G.; Santacruz-Cruz, Maria Isabel; Diaz, Ana; Trtik, Pavel; [et al.] (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 ...
  • A comparative study of experimental configurations in synchrotron pair distribution function 

    Zea-Garcia, Jesus D.; De la Torre, Angeles G.; Aranda, Miguel A. G.; Cuesta, Ana (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 ...
  • Alite-belite-ye'elimite cements: Effect of dopants on the clinker phase composition and properties 

    Zea-Garcia, Jesus D.; Aranda, Miguel A.G.; De la Torre, Angeles G.; Santacruz-Cruz, Maria Isabel (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 

    Londono-Zuluaga, Diana; Tobón, Jorge Iván; Aranda, Miguel A.G.; Santacruz, Isabel; De la Torre, Angeles G. (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 

    Cuesta, Ana; Aranda, Miguel A.G.; Santacruz-Cruz, Maria Isabel; De la Torre, Angeles G.; Zea-Garcia, Jesus D. (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 

    García-Maté, Marta; Álvarez-Pinazo, Gema; León-Reina, Laura; Gomez-de-la-Torre, Maria de los Angeles (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 

    Zhao, Piqi; Liu, Xianping; De la Torre, Angeles G.; Lu, Lingchao; Sobolev, Konstantin (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 

    Cuesta, Ana; Zea-Garcia, Jesus D.; Londono-Zuluaga, Diana; De la Torre, Angeles G.; Santacruz, Isabel; [et al.] (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 

    Zea-Garcia, Jesus D.; Gomez-de-la-Torre, Maria de los Angeles; Santacruz-Cruz, Maria Isabel; Londono-Zuluaga, Diana; García-Maté, Marta; [et al.] (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 

    Cuesta, Ana; Zea-Garcia, Jesus D.; Londono-Zuluaga, Diana; De la Torre, Angeles G.; Santacruz, Isabel; [et al.] (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 

    Cuesta, Ana; De la Torre, Angeles G.; Losilla, Enrique R.; Peterson, Vanessa K.; Rejmak, Pawel; [et al.] (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 

    Cuesta, Ana; Álvarez-Pinazo, Gema; García-Maté, Marta; Santacruz, Isabel; Aranda, Miguel A. G.; [et al.] (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 

    Cuesta, Ana; Álvarez-Pinazo, Gema; Sanfeliz-Garcia, Susana; Peral, Inma; Aranda, Miguel A. G.; [et al.] (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 

    Cuesta, Ana; Santacruz, Isabel; Sanfeliz-Garcia, Susana; Fauth, François; Aranda, Miguel A. G.; [et al.] (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 

    Cuesta, Ana; De la Torre, Angeles G.; Losilla, Enrique R.; Santacruz, Isabel; Aranda, Miguel A. G. (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 

    Aranda, Miguel A. G.; De la Torre, Angeles G.; León-Reina, Laura (Mineralogical Society of America, 2012)
  • Rietveld quantitative phase analysis of yeelimite-containing cements 

    Álvarez-Pinazo, Gema; Cuesta, Ana; García-Maté, Marta; Santacruz, Isabel; Losilla, Enrique R.; [et al.] (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 

    Álvarez-Pinazo, Gema; Cuesta, Ana; García-Maté, Marta; Santacruz, Isabel; Losilla, Enrique R.; [et al.] (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 

    García-Maté, Marta; De la Torre, Angeles G.; León-Reina, Laura; Losilla, Enrique R.; Aranda, Miguel A. G.; [et al.] (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 ...

Más