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-forming plastics from thermogravimetry, application to a phenolic plastic . J Polym Sci . 1964 ; C6 : 6 183 – 195 . 32. Kissinger , HE . Reaction kinetics in differential thermal analysis . Anal

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. J Solid State Electrochem 6 : 111 – 118 10.1007/s100080100200 . 12. Ferrow , EA , Mannerstrand , M , Berg , B 2005 Reaction kinetics and oxidation mechanisms of the conversion of

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Abstract  

A kinetic study of hydrogen isotope exchange was carried out in a H2/Pd membrane/organic compound system for a number of compounds in the 0.2–20 kPa H2 pressure range. The results suggest a low specificity of the reaction kinetics for the compounds used. Possible reaction mechanisms are discussed and analyzed.

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Abstract  

Faraday induced the mechanochemical reduction of AgCl with Zn, Sn, Fe and Cu in 1820, using trituration in a mortar. This experiment is revisited, employing a mortar-and-pestle and a ball mill as mechanochemical reactors. The reaction kinetics depends both on the thermochemical properties and the hardness of the reactants. When using Zn as the reducing agent, Faraday likely observed a mechanically induced self-sustaining process (MSR), or at least he came very close to doing so.

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Studies on the reaction kinetics and mechanism of the synthesis of the Zn2.5VMoO8 compound in the solid state have been carried out in situ in a high-temperature X-ray diffraction attachment. The apparent activation energy, 21226 kJ mol-1 was calculated by using the diffusion controlled Ginstling-Brounstein model. There was also determined a temperature dependence of unit cell parameters for Zn3V2O8 and Zn2.5VMoO8.

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A new chemical species of bis(acetonitrile)bis(acetylacetonato)technetium(III), [Tc(acac)2(CH3CN)2]+, has been prepared by the reaction of tris(acetylacetonato)technetium(III) with acetonitrile in the presence of a strong acid, perchloric or hydrochloric acid. The reaction kinetics were followed by observing spectral change of Tc(acac)3 in the UV-visible region. The complex has been characterized by combination of elemental analyses, IR and UV-visible spectrophotometry, ion-exchange chromatography, and paper electrophoresis. Applicability of this substance to synthesize mixed-ligand technetium(III) complexes was discussed based on the solubility of this complex and the ease of substitution of the acetonitrile ligand.

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The kinetic and solvent isotope effects during the maleic acid heterogeneous catalytic hydrogenation and deuteration in the light and heavy water have been studied. Also the effect of the γ and neutron irradiation on the Ni−ZnO catalysts (with various ratios of components) on the reaction kinetics and mechanism has been measured, as well as the effect of pH on the adsorption behaviour of maleic acid and the temperature depencence of the reaction rate. Existence of different adsorption centers for hydrogen and maleic acid could be deduced from these experiments. A reaction mechanism based on the two-dimensional diffusion of components in the surface is proposed.

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Abstract  

The reaction kinetics of the mesoporous powder, MCM-TP, anchored with synergistic extractant TOPO-P204, with Pd2+ in spent fuels have been investigated. The results showed that the reaction rate was independent of pellet size, which suggested that the powder pellet was highly porous and was composed of plate-like “grains”. This analysis was confirmed by observing the surface and cross section of the pellet with SEM. It provided the physical basis for establishing the liquid-solid reaction model of mesoporous powders: P-G* model. The calculated curves from the model were in good agreement with the experimental results.

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Abstract  

The thermal stability of lithium-ion battery cathode could substantially affect the safety of lithium-ion battery. In order to disclose the decomposition kinetics of charged LiCoO2 used in lithium ion batteries, thermogravimetric analyzer (TG) and C80 microcalorimeter were employed in this study. Four stages of mass losses were detected by TG and one main exothermic process was detected by C80 microcalorimeter for the charged LiCoO2. The chemical reaction kinetics is supposed to fit by an Arrhenius law, and then the activation energy is calculated as E a=148.87 and 88.87 kJ mol−1 based on TG and C80 data, respectively.

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Isothermal cure characterization of dicyclopentadiene

The glass transition temperature and conversion

Journal of Thermal Analysis and Calorimetry
Authors: X. Liu, X. Sheng, J. Lee, and M. Kessler

Abstract  

Conversion (α) and the glass transition temperature (T g) were investigated during the isothermal cure of endo-dicyclopentadiene (DCPD) with a Grubbs catalyst for different temperatures using differential scanning calorimetry. Conversion vs. In (time) data at an arbitrary reference temperature were superposed by horizontal shift and the shift factors were used to calculate an Arrhenius activation energy. Glass transition temperature vs. conversion data fell on a single curve independent of cure temperature, implying that reaction of the norbornene and cyclopentene ring of DCPD proceeds in a sequential fashion. Implications of the isothermal reaction kinetics for self-healing composites are discussed.

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