There are many thermoanalytical techniques but only several of them such as thermogravimetric analysis (TG), high resolution thermogravimetric analysis (Hi-Res™ TG), derivative thermogravimetry (DTG), differential thermal analysis (DTA), calorimetry, differential scanning calorimetry (DSC), modulated differential scanning calorimetry (MDSC), evolved gas analysis (EGA), transient thermal analysis (TTA) and thermal conductivity (k) have selected to be discussed in this paper. Simultaneous thermal analysis (STA) is ideal for investigating issues such as the glass transition of modified glasses, binder burnout, dehydration of ceramic materials or decomposition behaviour of inorganic building materials, also with gas analysis. Selected applications of various thermoanalytical techniques from medicine to construction have also been discussed in this paper.

Selected thermoanalytical methods and their applications from medicine to construction

Using gypsum to control hydration kinetics of CSA cements

Potassium acid phthalate (KAP) which is also known as potassium hydrogen phthalate (KC8H5O4), a semi-organic compound was grown from its aqueous solution only by slow evaporation method at room temperature. The effect of metallic salts HgCl2 and PbCl2 as dopants in the growth aspects, thermal properties and SHG efficiency of KAP were determined using UV-VIS, FTIR spectral studies, thermal (TG and DTA) analysis and NLO test. There is only one significant mass loss step on TG curve of pure and doped KAP crystal. DTA curve exhibit a higher peak temperature in case of doped KAP crystal compared to those of pure KAP crystals.

Thermal analysis, effect of dopants, spectral characterisation and growth aspects of kap crystals

Commercial wheat gluten (WG) films, hard wheat gluten films and soft wheat gluten films, plasticized with glycerol have been cast from water–ethanol solutions. The effect of aging on various film properties has been investigated. The films were aged for about 6 months at 50% relative humidity and ~25 °C, and the mechanical (tensile strength and the percentage of elongation at break (E
 b)), thermal (TG and DSC) and Attenuated Total Reflectance (ATR)-FTIR spectral properties have been studied. Changes in the protein structure were determined by ATR-FTIR spectroscopy. Films from soft WG exhibited the highest E
 b (508%) and the highest TS (6.33 MPa). The TG analysis results show that the moisture content in all three kinds of WG protein films is about 5%. The absence of the glycerol phase transition in DSC curves implies that there is no separate phase containing glycerol in the WG protein-glycerol films with 40% glycerol.

Edible wheat gluten (WG) protein films

Armouring of well cement in H2S–CO2 saturated brine by calcite coating – Experiments and numerical modelling

Hydration behavior of dicalcium silicate (C2S) (Cement chemistry nomenclature is used where C=CaO, S=SiO2, A=Al2O3, \( \overline S \)S=SO3) and gehlenite (C2AS), synthesized by sol–gel method was investigated by means of isothermal heat flow calorimeter at different temperatures. These phases were obtained by crystallization processing at different temperatures from their xerogels (nano-crystalline) prepared by the sol–gel method at ambient temperature. The crystallization of C2S begins below 600°C and it is well crystallized at 900°C. X-ray diffraction patterns reveal that β-C2S is formed and it remains stable since after slow cooling. The crystallization of C2AS xerogels starts with the formation of C2S, then it reacts with alumina to form mineral C2AS at 1100°C. The effect of hydration temperature upon the hydration reaction of C2S obtained at 600 and 900°C and C2AS annealed at 600 and 1100°C was investigated by means of isothermal calorimeter. An increase in the temperature of hydration brought about initial acceleration of all samples, as indicated by the increased magnitude of peak of calorimetric curves. The microstructure of the samples cured at hydrothermal condition after 1 and 7 days has been examined by means of scanning electron microscopy (SEM). Fine crystals of calcium silicate hydrate (C–S–H) were developed in C2S samples, while C2AS has been hydrated to form gehlenite hydrate supplemented by C–S–H.

M. Dovál

Papers

Hydration behavior of C2S and C2AS nanomaterials, synthetized by sol–gel method