Listar QICM - Artículos por título
Mostrando ítems 28-47 de 182
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Chemistry and Mass Density of Aluminum Hydroxide Gel in Eco-Cements by Ptychographic X-ray Computed Tomography
(ACS, 2017)Eco-cements are a desirable alternative to ordinary Portland cements because of their lower CO2 footprints. Some ye’elimite-based ecocements are attracting a lot of interest. Understanding the reasons for the mechanical ... -
Clinkering and hydration of belite-ye'elimite-alite cement
(Elsevier, 2017)Some belite-ye´elimite-ferrite (BYF) cements present low mechanical strengths mainly due to the slow reactivity of belite. A solution to this problem may be the activation of BYF clinkers by preparing them with a coexistence ... -
Common Structural Features in Calcium Hydroxyphosphonoacetates. A High-Throughput Screening
(2011-03-11)R,S-Hydroxyphosphonoacetic acid (H3HPA) is an inexpensive multidentate organic ligand widely used for the preparation of organo-inorganic hybrid materials. There are reports of several crystal structures and the variability ... -
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 ... -
Crystal engineering in confined spaces. A novel method to grow crystalline metal phosphonates in alginate gel systems
(The Royal Society of Chemistry, 2012)In this paper we report a crystal growth method for metal phosphonate frameworks in alginate gels. It consists of a metalcontaining alginate gel, in which a solution of phosphonate ligand is slowly diffused. Crystals of ... -
CuO metallic aerogels with a tailored nodular morphology
(RSC (Royal Society of Chemistry), 2023-09-28)This work reports, for the first time, an efficient and fast microwave-based method for the preparation of CuO aerogels. For that, CuCl2, glyoxylic acid and sodium carbonate are employed as reagents. Different experimental ... -
Difracción de rayos-x (DRX) y cementos: desde la investigación hasta el control de calidad
(2019-06-20)Los materiales de construcción son componentes complejos de gran interés comercial. Por ello, el conocimiento cuantitativo de su mineralogía a través de la difracción de rayos X (DRX) es de crucial importancia para optimizar ... -
Divalent Metal Vinylphosphonate Layered Materials: Compositional Variability, Structural Peculiarities, Dehydration Behavior, and Photoluminescent Properties
(American Chemical Society, 2011-09-27)A family of M-VP (M = Ni, Co, Cd, Mn, Zn, Fe, Cu, Pb; VP = vinylphosphonate) and M-PVP (M = Co, Cd; PVP = phenylvinylphosphonate) materials have been synthesized by hydrothermal methods and characterized by FTIR, elemental ... -
Doping effects on the structure and electrical properties of La2Ce2O7 proton conductors.
(Elsevier, 2020-01-01)Recent studies have reported that the conductivity of La2Ce2O7 proton conductors is improved by aliovalent doping, despite the high concentration of oxygen vacancies in the pristine material. In this study, we provide ... -
Durability and performance of CGO barriers and LSCF cathode deposited by spray-pyrolysis
(Elsevier, 2018-03-19)Ce0.9Gd0.1O1.95 (CGO) protective layers are prepared by two different methods to prevent the reaction between the Zr0.84Y0.16O1.92 (YSZ) electrolyte and the La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode. In the first method, ... -
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 ... -
Early-age reactivity of calcined kaolinitic clays in LC3 cements: a multitechnique investigation including pair distribution function analysis
(Taylor & Francis, 2022-09)Limestone Calcined Clay Cements, LC3, allows CO2 emissions savings up to 40%. The resulting binders have competitive mechanical performances after a week. However, the reactivity of LC3 at early ages is slow and should be ... -
Effect of Basic Promoters on Porous Supported Alumina Catalysts for Acetins Production
(IOAP-MDPI, 2022-12-09)A facile strategy for the design of porous supports was obtained by modifying the sol-gel method followed by the wet impregnation technique. In this respect, herein, the acidity of the γ-Al2O3 phase was modulated by adding ... -
Effect of boron and water-to-cement ratio on the performances of laboratory prepared Belite-Ye'elimite-Ferrite (BYF) cements
(2021)The effect of superplasticiser, borax and the water-to-cement ratio on BYF hydration and mechanical strengths has been studied. Two laboratory-scale BYF cements—st-BYF (with -C2S and orthorhombic C4A3 S) and borax-activated ... -
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 ... -
Effect of Capping Ligands for the Synthesis of Gold Nanoparticles and on the Catalytic Performance for the Oxidation of 5-Hydroxymethyl-2-furfural.
(MDPI, 2023-06-09)Different series of Au on carbon catalysts were prepared via sol-immobilization to investigate the role of polymers (polyvinylpyrrolidone PVP, polyethylene glycol PEG and polyvinyl alcohol PVA), employed as gold nanoparticle ... -
Effect of Microencapsulated Phase Change Materials on the Flow Behavior of Cement Composites
(2019)Microencapsulated phase change materials (MPCMs) were incorporated into cement pastes of Portland cement (PC). Minislump tests and rheological properties of cement pastes containing three MPCMs with different surfaces ... -
Effect of the treatment with H3PO4 on the catalytic activity of Nb2O5 supported on Zr-doped mesoporous silica catalyst. Case study: glycerol dehydration.
(Elsevier B.V., 2017-09-06)We have previously demonstrated the influence of the niobium species over the glycerol dehydration reaction and how the catalyst regeneration by thermal treatment modified the catalytic performance due to the transformation ... -
Effect of Zn addition on the structure and electrochemical properties of codoped BaCe0.6Zr0.2Ln0.2O3-δ (Ln=Y, Gd, Yb) proton conductors
(Elsevier, 2018-05-02)In this work, BaCe0.6Zr0.2Y0.2-xYbxO3-δ and BaCe0.6Zr0.2Gd0.2-xYbxO3-δ (x=0–0.20), proton conducting materials are prepared by the freeze-drying precursor method. The sintering conditions were optimized by adding ... -
The effects of MgO, Na2O and SO3 on industrial clinkering process: phase composition, polymorphism, microstructure and hydration, using a multidisciplinary approach
(2019-07-02)The present investigation deals with how minor elements (their oxides: MgO, Na2O and SO3) in industrial kiln feeds affect (i) chemical reactions upon clinkering, (ii) resulting phase composition and microstructure ...