Listar QICM - Artículos por título
Mostrando ítems 86-105 de 133
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Phase and microstructure evolutions in LC3 binders by multi-technique approach including synchrotron microtomography
(Elsevier, 2021-06-19)Limestone Calcined Clay Cements, LC3, are attracting a lot of attention as it is possible to reduce the clinker factor by 50%, which means a cement CO2 footprint reduction of 40%. This is compatible with maintaining the ... -
Phase Transformation Dynamics in Sulfate-Loaded Lanthanide Triphosphonates. Proton Conductivity and Application as Fillers in PEMFCs
(ACS Publications. American Chemical Society, 2021)Phase transformation dynamics and proton conduction properties are reported for cationic layer-featured coordination polymers derived from the combination of lanthanide ions (Ln3+) with nitrilo-tris(methylenephosphonic ... -
Phase-selective degree of hydration at setting: An in situ synchrotron diffraction study
(Elsevier, 2022-03)Setting of Portland cements is still not well understood. Previous studies used techniques that analyse the pastes as a whole to correlate setting times with degree of hydration. Here, in-situ synchrotron X-ray diffraction ... -
Phosphonate Decomposition-Induced Polyoxomolybdate Dumbbell-Type Cluster Formation: Structural Analysis, Proton Conduction, and Catalytic Sulfoxide Reduction
(ACS publications, 2019-08-12)The reaction of MoO4^2− with a number of phosphonic acids [bis-(phosphonomethyl)glycine, R,S-hydroxyphosphonoacetic acid, 1-hydroxyethane-1,1-diphosphonic acid, phenylphosphonic acid, aminotris(methylene phosphonic acid), ... -
Photodegradation of Phenol over a Hybrid Organo-Inorganic Material: Iron(II) Hydroxyphosphonoacetate
(American Chemical Society, 2012-06-20)Water treatment is a hot topic, and it will become much more important in the decades ahead. Advanced oxidation processes are being increasingly used for organic contaminant removal, for example using photo-Fenton reactions. ... -
Porous SiO2 Nanospheres Modified with ZrO2 and Their Use in One- Pot Catalytic Processes to Obtain Value-Added Chemicals from Furfural
(American Chemical Society, 2021-11-26)Porous SiO2 nanospheres have been modified with different proportion of ZrO2 to obtain catalysts with Si/Zr molar ratio between 2.5 and 30. These materials were characterized by X-ray diffraction, transmission electron ... -
Portland and belite cement hydration acceleration by C-S-H seeds with variable w/c ratios
(Materials, 2022)The acceleration of very early age cement hydration by C-S-H seeding is getting attention from scholars and field applications because the enhanced early age features do not compromise later age performances. This acceleration ... -
Portland and Belite Cement Hydration Acceleration by C-S-H Seeds with Variable w/c Ratios
(IOAP-MPDI, 2002-05-16)The acceleration of very early age cement hydration by C-S-H seeding is getting attention from scholars and field applications because the enhanced early age features do not compromise later age performances. This acceleration ... -
Processing and characterisation of standard and doped alite-belite-ye'elimite ecocement pastes and mortars
(2020-02-26)Here, we report the processing optimisation of two laboratory-prepared alite-belite-ye'elimite ecocements (standard and doped) that release to the atmosphere ~13% less CO2 than Portland Cement during fabrication. The ... -
Production of Biofuels by 5-Hydroxymethylfurfural Etherification Using Ion-Exchange Resins as Solid Acid Catalysts
(mdpi, 2020-11-09)In this work, acidic ion-exchange resins with strong Brönsted sulphonic groups were assessed in the catalytic etherification of the platform molecule 5-(hydroxymethyl)furfural (HMF) to 5-(ethoxymethyl)furfural (EMF), a ... -
Properties and Applications of Metal Phosphates and Pyrophosphates as Proton Conductors
(MDPI, 2022-02-09)We review the progress in metal phosphate structural chemistry focused on proton conductivity properties and applications. Attention is paid to structure–property relationships, which ultimately determine the potential ... -
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 ... -
Quantitative disentanglement of nanocrystalline phases in cement pastes by synchrotron ptychographic X-ray tomography
(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 ... -
Reactive belite stabilization mechanisms by boron-bearing dopants
(Elselvier, 2012-01-27)Belite-rich cements hold promise for reduced energy consumption and CO2 emissions, but their use is hindered by the slow hydration rates of ordinary belites. This drawback may be overcome by activation of belite by doping. ... -
Recent Advances in Mechanochemical Pretreatment of Lignocellulosic Biomass
(IOAP-MPDI, 2022-08-17)Biorefineries are industrial facilities where biomass is converted into chemicals, fuels and energy. The use of lignocellulose as raw material implies the development of pretreatments to reduce its recalcitrant character ... -
Recent studies of cements and concretes by synchrotron radiation crystallographic and cognate methods
(Taylon & Francis, 2015)The portfolio of available synchrotron radiation techniques is increasing notably for cements and pastes. Furthermore, sometimes the terminology is confusing and an overall picture highlighting similarities and differences ... -
Recovery of pentoses-containing olive stones for their conversion into furfural in the presence of solid acid catalysts
(2020-06-24)Olive stones were employed as feedstock for furfural production in two stages: 1) autohydrolysis of hemicellulosic fraction to recover their pentoses, mainly xylose, and 2) subsequent dehydration of pentoses into furfural. ... -
Relationship between the Structure and Transport Properties in the Ce1−xLaxO2−x/2 System
(American Chemical Society, 2019-06-25)La-doped CeO2 materials have been widely investigated for potential applications in different high-temperature electrochemical devices, such as fuel cells and ceramic membranes for hydrogen production. However, the crystal ... -
Rheological and hydration characterization of calcium sulfoaluminate cement pastes
(2015-05-14)Calcium sulfoaluminate (CSA) cements are currently receiving a lot of attention because their manufacture produces less CO2 than ordinary Portland cement (OPC). However, it is essential to understand all parameters which ... -
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 ...