Listar QICM - Artículos por fecha de publicación
Mostrando ítems 41-60 de 184
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Experimental and theoretical high pressure study of calcium hydroxyaluminate phases
(Elsevier, 2017)Five calcium hydroxyaluminate phases have been investigated by synchrotron powder diffraction at high-pressure: two hydrogarnets, kuzelite, stratlingite and ettringite. The obtained bulk modulus, K0, for kuzelite, stratlingite ... -
Zinc(II), cobalt(II) and manganese(II) networks with phosphoserine ligand: Synthesis, crystal structures magnetic and conduction properties
(The Royal Society of Chemistry, 2017)A series of zinc(II), cobalt(II) and manganese(II) coordination networks with the phosphoserine ligand (Pser) is synthesized and characterized. Whereas in compounds 1 and 2 with the general formula [M(Pser)]n [M = Zn (1) ... -
In situ hydration imaging study of a ye'elimite paste by ptychographic x-ray computed tomography
(2017)Eco-cements are a desirable alternative to ordinary Portland cements because of their lower CO2 footprints. For instance, the manufacture of Calcium SulfoAluminate (CSA) cements is more environmentally friendly than that ... -
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 ... -
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 ... -
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 ... -
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 ... -
Structural variability in M2+ 2-hydroxyphosphonoacetate moderate proton conductors
(De Gruyter, 2017)The structural variability of two series of Mg2+- and Zn2+- 2-hydroxyphosphonoacetates have been studied in the range of 25–80 °C and 95 % relative humidity in order to correlate the structure with the proton conductivity ... -
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 ... -
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 ... -
Influence of Proton Conducting Cations on the Structure and Properties of 2D Anilate-Based Magnets
(ACS publications, 2017-11-01)The syntheses, structures, magnetic, and proton conductivity properties of a family of bimetallic anilate-based compounds with inserted alkylammonium cations are presented. The structures of (Me2NH2)[MnIICrIII(Br2An)3]·2H2O ... -
Highly efficient La0.8Sr0.2MnO3-δ - Ce0.9Gd0.1O1.95 nanocomposite cathodes for solid oxide fuel cells
(Elsevier, 2017-12-15)La0.8Sr0.2MnO3-δ-Ce0.9Gd0.1O1.95 (LSM-CGO) nanostructured cathodes are successfully prepared in a single process by a chemical spray-pyrolysis deposition method. The cathode is composed of nanometric particles of approximately ... -
LSCF-CGO nanocomposite cathodes deposited in a single step by spraypyrolysis.
(Elsevier, 2018-01-01)La0.6Sr0.4Co0.2Fe0.8O3-δ-Ce0.9Gd0.1O1.95 (LSCF-CGO) nanostructured cathodes with different LSCF-content are prepared in a single step by spray-pyrolysis deposition, simplifying notably the fabrication process compared ... -
Error analysis and correction for quantitative phase analysis based on Rietveld-internal method: Whether the minor phases can be ignored?
(MDPI, 2018-02)The Rietveld-internal standard method for Bragg-Brentano reflection geometry (q/2q) X-ray diffraction (XRD) patterns is implemented to determine the amorphous phase content. The effect of some minor phases on quantitative ... -
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, ... -
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 ... -
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 ... -
Three-Component Copper-Phosphonate-Auxiliary Ligand Systems: Proton Conductors and Efficient Catalysts in Mild Oxidative Functionalization of Cycloalkanes
(ACS publications, 2018-08-13)The synthesis, structural characterization, topological analysis, proton conductivity, and catalytic properties are reported of two Cu(II)-based compounds, namely a dinuclear Cu(II) complex [Cu2(μ-VPA)2(phen)2(H2O)2]· 8H2O ... -
From light to heavy alkali metal tetraphosphonates (M = Li, Na, K, Rb, Cs): cation size-induced structural diversity and waterfacilitated proton conductivity
(The Royal Society of Chemistry, 2018-09)A family of alkali metal-based frameworks containing the tetraphosphonate ligand hexamethylenediamine- N,N,N′,N′-tetrakisIJmethylenephosphonic acid), HDTMP, is reported. A cation size-induced structural diversity, from ... -
High-Throughput Synthesis of Pillared-Layered Magnesium Tetraphosphonate Coordination Polymers: Framework Interconversions and Proton Conductivity Studies
(MDPI, www.mdpi.com/journal/inorganics, 2018-09-11)Novel pillared-layered framework materials were synthesized by high-throughput or microwave-assisted methodology that contain Mg2+ and the zwitterionic linker HDTMP (hexamethylenediamine-N,N,N0,N0-tetrakis(methylenephosphonic ...