The research presented in this paper is devoted to the intriguing phenomenon of thermal decomposition that takes place during continuous cooling after being initiated by heating to higher temperature. This paper describes the principles of detecting this phenomenon and measuring its kinetics. As one of the possible ways, the process can be detected and its kinetics can be measured by means of differential scanning calorimetry provided that cooling is performed several hundred times slower than heating. By way of illustration, the thermal degradation of isotactic polystyrene and thermal dehydration of lithium sulfate monohydrate have been studied upon cooling and heating. The kinetics of both processes have been analyzed by means of the isoconversional methodology. For polystyrene, the kinetics of degradation upon cooling and heating have been similar. The thermal dehydration of lithium sulfate monohydrate has revealed that cooling kinetics differ significantly from the kinetics measured upon heating. It is proposed that such differences should be observed in multi-step processes whose activation energy varies with reaction progress.
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http://dx.doi.org/10.1039/c6cp04507c | DOI Listing |
Nanoscale Adv
December 2024
Institute of Inorganic Chemistry (IAC), Karlsruhe Institute of Technology (KIT) Engesserstraße 15 D-76131 Karlsruhe Germany
Pt-CeO nanosponges (1 wt% Pt) with high surface area (113 m g), high pore volume (0.08 cm g) and small-sized Pt nanoparticles (1.8 ± 0.
View Article and Find Full Text PDFFood Res Int
January 2025
School of Pharmacy, Anhui University of Chinese Medicine, Hefei 230012, China. Electronic address:
Chrysanthemi Flos has been consumed as floral tea for centuries, but the effects of stir-frying on its chemical profile, sensory characteristics, and bioactivity remain unclear. This study used untargeted metabolomics, sensory assessment (E-eye, E-nose, E-tongue), and antioxidant activity evaluation to investigate compositional changes and their effects. In the metabolomics analysis, a total of 101 non-volatile and 306 volatile differential metabolites were identified.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China. Electronic address:
Cellulose is a renewable biodegradable polymer derived from abundant natural resources. Substituting petroleum-based polymers with cellulose-based bioplastics is an effective way to alleviate environmental issues like resource depletion and white pollution. However, challenges such as poor thermostability, difficulty in thermoforming and water sensitivity seriously hinder the fabrication and use of cellulose-based bioplastics.
View Article and Find Full Text PDFEnviron Res
January 2025
College of Civil Engineering, Hefei University of Technology, Hefei, 238000, China; Chinaland Solar Energy Co., Ltd., Hefei, 238000, China. Electronic address:
The preparation strategy is the important factor to obtain the effective photocatalyst, and the thermal decomposition could be used to prepare photocatalysts with high crystallinity and photoactivity. In this paper, thermal decomposition method was used to deposit CuO nanoparticles on TiO nanotube arrays (TiO NTs), and the TiO NTs/CuO exhibited remarkably high visible light absorption and photoelectrocatalytic performances toward dye degradation and Cr(VI) reduction. The potential degradation pathway and toxicities of rhodamine B (RhB) dyes and intermediates were investigated.
View Article and Find Full Text PDFDiscov Nano
January 2025
Particle Engineering Centre, Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim, 7491, Norway.
The increasing demand for magnetic iron oxide nanoparticles (IONPs) in biomedicine necessitates efficient and scalable production methods. Thermal decomposition offers excellent tailoring of the particle properties but its discontinuous batch-operation is restricting scale-up and industrial application. To overcome these challenges, several studies have demonstrated semi-continuous thermal decomposition by slowly injecting the precursor, though only half of them produce magnetite IONPs and even fewer use iron oleate precursors.
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