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This study investigates the kinetics data of glass wool (GW) and extruded polystyrene (XPS) insulation materials used in cladding systems using a systematic framework. The determination of appropriate kinetic properties, such as pre-exponential factors, activation energy and reaction orders, is crucial for accurately modelling the full-scale fire performance of insulation materials. The primary objective of this research is to extract thermal and kinetics data of XPS and GW insulation materials employed in high-rise buildings. To obtain these properties, thermogravimetric analysis (TGA) is conducted at four different heating rates: 5, 10, 15 and 20 K/min. The TGA results serve as the basis for determining the kinetic properties using a combination of model-free and model-based methods. The outcomes of this study are expected to be highly beneficial in defining the pyrolysis reaction steps and extracting kinetics data for fire modelling of such insulation materials. This information will enhance the understanding of the fire behaviour and performance of these materials during fire incidents, aiding in developing more accurate fire models and improving fire safety strategies for cladding systems in high-rise buildings. [ABSTRACT FROM AUTHOR]

Based on Kinetics and thermodynamics theory，the migration rules of five basic elements including C，H，O，N and S were studied，and the variation trend of main functional groups was also analyzed during the coal heating process. The results show that variation of carbon oxide compounds played a leading role in the physical and chemical adsorption phase，while the variation frequency of hydrocarbons and nitrogen compounds exceeded carbon oxide compounds. The apparent activation energy value of H element was the smallest and the energy value of O and S element were negative. The migration process of C，H and N was an endothermic process respectively and that of O and S was an exothermic process. Aliphatic C—H in the coal was gradually decreased when coal was heated. The contents of COOH and C=O had same variation trend，and it was obviously that the contents of both groups increased gradually over 120 ℃.Besides，the chemical reaction steps involved in coal low-temperature oxidation were also studied. [ABSTRACT FROM AUTHOR]

Deuterium isotope exchange was employed to investigate some of the reaction steps for the hydrodechlorination of CF3CFHCl and CH3CH2Cl on supported Pd catalysts. Hydrodechlorination rates for both compounds using D2 or H2 were identical. It is concluded that H or D species are not involved in the rate-determining step of the hydrodechlorination reaction. Experiments using a combined H2 and D2 feed for hydrodechlorination of CF3CFHCl showed that CF3CFH2 was preferentially formed over CF3CFHD. This experimental observation can be explained by isotope effects and is consistent with gas phase H2 in equilibrium with adsorbed H and a reaction step consisting of the combination of surface adsorbed CF3CFH&z.sbnd; species with adsorbed H. Deuterated product distributions of CF3CFHCl and CH3CH2Cl hydrodechlorination experiments with D2 were analyzed to explore the reaction steps beyond the kinetically relevant steps. The main product of CF3CFHCl hydrodechlorination was CF3CFHD, showing that the C&z.sbnd;Cl bond is preferentially broken. In the case of CH3CH2Cl, substantial C&z.sbnd;H bond breaking accompanies the initial C&z.sbnd;Cl scission. Deuterium exchange experiments with ethane on Pd/C and Pd/ZrO2 were also investigated and the results indicate that the CH3CH2Cl product distribution is not caused by re-adsorption and subsequent exchange reaction of ethane. [Copyright &y& Elsevier]

Intensive and broad studies of chemical reactions concerning X(NSO)2 (X=Se, Te), X2Te(NSO)2 (X=F, Cl, Br) and X′2Te(NSC)2X′2 (X′=F, Cl) provides besides new interesting compounds also valuable intermediates for a better understanding of reaction pathways in chalcogen–nitrogen chemistry. Based on the mechanism elucidated for the formation of [SeSeNSN+]2[MF6−]2 or [ClSeSeNSN][SbCl6−] from Se(NSO)2 and MF5 (M=As, Sb, Nb) or Se(NSO)2 and SbCl5 respectively an interpretation of the reaction sequences of other procedure such as Te(NSO)2+SbCl5 or e.g. Cl2Te(NSO)2 with MCl3 (M=Ga, Al, Fe) could be provided. It was proved that a desulfurisation process is responsible for transforming Cl2Te(NSO)2 and derivated products in the presence of MCl3 into [(Cl2Te)2N+][MCl4−] and [ClTeSNSN+][MCl4−]. The results gained in these studies led directly to the synthesis of [SSNNN+][TeCl5−], the first ring with three cummulated nitrogen atoms. In order to learn more about the possible structures of Cl2Te(NSN)2TeCl2, careful and intensive investigations proved the formation of the cage N[Te(Cl)NSN]3. A thorough reinvestigation of the original synthesis of the cage yielded S4N4 as an additional product and by varying the stoichiometry between the educts TeCl4 and (CH3)3SiNSNSi(CH3)3 important intermediates could be detected and isolated. They provided the base for understanding the consecutive steps during the procedure between educts and to yield products. Fluorine substituted acyclic, cyclic, neutral and ionic chalcogen–nitrogen compounds are described as well as relationship among themselves and related compounds. Interesting and valuable correlations are presented and evaluated. [Copyright &y& Elsevier]