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Abstract  

The thermal behaviour of a new kind of hybrid system based on silanized poly(ether-urethanes) (SPURs) has been analyzed by thermogravimetric analysis (TG). The influence of the chemical nature of employed alkoxysilanes, polyether diol molecular weight and the physical state of the obtained hybrids (cured and non-cured) has been studied. The results show that in the non-cured state, aminosilane-based systems present a higher stability compared with those based on isocyanatesilane. However, in the cured state, both types of hybrids present a similar thermal stability, but much higher than their corresponding partners before the curing process. The presence of the inorganic silica network improves the thermal stability of all the systems studied.

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Abstract  

The thermal behavior of the new inorganic-organic nanohybrid materials obtained by intercalation of chloramphenicol and salicylate into layered double hydroxides (LDHs) by direct synthesis method, anion exchange reaction and the reconstruction method was evaluated by dynamic thermogravimetric analysis in air, at heating rates of 5°C min−1. The XRD patterns of the samples are characteristic for those of well crystallized solids with layered double hydroxide structures. The FTIR spectroscopy results show the presence of the organic compound within the network structure of the synthesized LDHs. The kinetic parameters (reaction order (n) apparent activation energy (E a) and pre-exponential factor (lnA) were calculated by the Coats-Redfern method. The compensation effects were determined.

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Abstract  

Pyrolytic process has a promising potential for the environmentally friendly upgrading of lignocellulosic materials and plastic waste. The co-pyrolysis of olive residue and poly(vinyl chloride) was investigated under nitrogen atmosphere by dynamic thermogravimetric analysis in the temperature range of 300–975 K. Two main stages of mass loss have been evidenced by TG analysis. The first occurs in the temperature range of 420–684 K, and the second occurs at 631–840 K. This research was focused on the interaction between olive residue and poly(vinyl chloride) during the pyrolysis process. Discrepancies between the experimental and calculated TG/DTG profiles were considered as a measurement of the extent of interactions occurring on co-pyrolysis. It was found that reactivity of olive residue was increased in olive residue/PVC mixture. In addition, a kinetic analysis was performed to fit thermogravimetric data, the mixture is considered as multistage process. A reasonable fit to the experimental data was obtained for all materials and their mixture by isoconversional Friedman method.

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The thermal transformations of a number of modelo-amic acids were investigated by thermogravimetric analysis (TG). The TG data pointed to cyclodehydration of the amic acids and accompanying thermal degradation processes. TG in combination with mass-spectrometric thermal analysis provided sufficient information for the description of these processes on both qualitative and quantitative levels.

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Abstract  

The transition of cubic indium hydroxide to cubic indium oxide has been studied by thermogravimetric analysis complimented with hot-stage Raman spectroscopy. Thermal analysis shows the transition of In(OH)3 to In2O3 occurs at 219 °C. The structure and morphology of In(OH)3 synthesised using a soft chemical route at low temperatures was confirmed by X-ray diffraction and scanning electron microscopy. A topotactical relationship exists between the micro/nano-cubes of In(OH)3 and In2O3. The Raman spectrum of In(OH)3 is characterised by an intense sharp band at 309 cm−1 attributed to ν1 In–O symmetric stretching mode, bands at 1137 and 1155 cm−1 attributed to In-OH δ deformation modes, bands at 3083, 3215, 3123 and 3262 cm−1 assigned to the OH stretching vibrations. Upon thermal treatment of In(OH)3, new Raman bands are observed at 125, 295, 488 and 615 cm−1 attributed to In2O3. Changes in the structure of In(OH)3 with thermal treatment is readily followed by hot-stage Raman spectroscopy.

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Co-firing of biomass with coals

Part 2. Thermogravimetric kinetic analysis of co-combustion of fir (Abies bornmulleriana) wood with Beypazari lignite

Journal of Thermal Analysis and Calorimetry
Authors: Sinem Taş and Yuda Yürüm

difference Thermogravimetric analysis TG measurements were performed on a Netzsch STA 449 C Jupiter differential thermogravimetric analyzer (precision of temperature measurement ±2 °C

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composite prepared with thermoplastic material, knowledge of influential factors such as temperature is paramount. In most cases, thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) is employed to study such factors. They can help

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temperature. The calcination process was characterised using thermogravimetric analysis coupled with mass spectrometry (TG–MS) for evolved gas analysis; characterisation of the calcination products was carried out using X-ray diffraction (XRD

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Using the thermal analysis of the Differential thermal analysis (DTA) and Thermogravimetric Analysis (TGA), the decomposition process was divided into three stages: the zero stage is the decomposition of impurities, and the mass loss in the first and

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degradation kinetics and mechanism of BO6 must be fully understood for successful use in manufacture and elevated temperature applications. Thermogravimetric analysis (TG) has been widely used to determine the kinetic parameters of the degradation

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