Effects of accelerated carbonation on properties of ceramic-based geopolymers

Journal of Thermal Analysis and Calorimetry - Geopolymers are considered as environmentally friendly binders with a high potential not only to lower the prices of binders, but mainly to decrease...     

Mechanical-acoustic study of electroporcelain mixture made under different compression pressures

Journal of Thermal Analysis and Calorimetry - This paper presents mechanical-acoustic study of samples made from electroporcelain mixture (type C 130) under five different compression...     

Multi-nuclear magnetic resonance study of Na3AlF6-AlPO4 molten and solidified mixtures

Phosphorus is one of the predominant impurities in the Hall-Heroult process for industrial aluminium production. The nature of the dissolved phosphorus species in the Na(3)AlF(6)-AlPO(4) system has been investigated by in situ high-temperature (HT) (19)F, (23)Na, (27)Al, (17)O, and (31)P NMR. The combination of these experiments enables to define the presence of PO(4)(3-), AlF(5)(2-) and (AlF(4)-O-PO(3))(4-) anions in the melt, and then the formation of Al-O-P bonding. Melts solidified at different cooling rates were characterised using various solid-state NMR techniques including multiple quantum magic angle spinning (MQMAS), rotational echo double resonance (REDOR) and heteronuclear single quantum correlation (HSQC). The glass obtained by the rapid quenching of the hypereutectic melt has been carefully described in order to better understand the structure of the melt.     

Changes in structure and composition of gypsum paste at elevated temperatures

Journal of Thermal Analysis and Calorimetry - The structure and composition of the gypsum at elevated temperatures were studied by means of scanning electron microscopy, X-ray diffraction (XRD) and...     

Phase composition of ceramic-based alkali-activated polymers: combination of X-ray diffraction and thermal analysis

Journal of Thermal Analysis and Calorimetry - Thermal properties and fire propagation performance were studied for the new and aged electrical wires. Two fine electrical wires were tested using the...     

XPS investigation on the surface chemistry of corrosion products on ZnMgAl-coated steel

In this work, a novel evaluation strategy for the X-ray photoelectron spectroscopy (XPS) chemical assessment is proposed to identify the corrosion products formed on the surface of hot-dip galvanized ZnMgAl coatings after exposure to standardized salt spray tests. The experiments demonstrate that the investigated system exhibits a problematic differential charging behavior between the different compounds, an effect which cannot be fully compensated for by the flood gun of the XPS system, making a reliable evaluation of the individual spectra impossible by using standard evaluation and fitting methods. For that reason, a new effective approach—taking the different charge shifts into account—was implemented and its reliability experimentally verified on model mixtures of assumed corrosion products with known composition. With this new approach, the chemical surface composition of an industrial sample of a corroded ZnMgAl coating was revealed and discussed in order to clearly demonstrate the potential of the proposed method for future corrosion studies.