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the melt viscosity, which determine hematite proportion and the size of the developing crystals. This article focuses on the kinetics study of the hematite crystallization in an aventurine glaze. The apparent activation energy, as a function of

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for solid-state phase transformation are the activation energy ( Q α ), and the growth exponent ( n ). The determination of these two parameters and their evolution with respect to time and temperature is of great importance to understand the phase

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Journal of Thermal Analysis and Calorimetry
Authors: Nagarajan David Mathan, Mahendran Arunjunairaj, Thangamani Rajkumar, Durairaj Ponraju, and Chinnaswamy Thangavel Vijayakumar

containing compounds and this has been reported in the literature [ 11 – 13 ]. The thermal stability of the compound PEPA is an important factor as it decides the processing and application ranges. The calculation of activation energy for degradation

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two stages—in the first stage, only the zeolitic waters are removed, by a diffusion mechanism, while in the second stage the strongly bonded water molecules are dehydrated. They estimated the values of activation energy and its dependence on the

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Isoconversional analysis of solid state transformations

A critical review. Part I. Single step transformations with constant activation energy

Journal of Thermal Analysis and Calorimetry
Authors: J. Farjas and P. Roura

where A is the pre-exponential factor, E is the activation energy, and R is the gas constant. For experiments carried out at a constant heating rate the explicit dependence on time of Eq. 1 can be eliminated with 3 where β ≡ d T /d t

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Thermal decomposition of hydromagnesite

Effect of morphology on the kinetic parameters

Journal of Thermal Analysis and Calorimetry
Authors: D. Bhattacharjya, T. Selvamani, and Indrajit Mukhopadhyay

controlled hydrothermal and simple precipitation process using MgCl 2 precursor [ 28 , 29 ]. The kinetic parameters were deduced by the model-free Friedman isoconversion and Flynn–Wall method. The dependence of the activation energy on the morphology is

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activation energy, R is the gas constant, and T is the absolute temperature. Selecting n th order reaction model in the light of a previously accomplished kinetics study of pistachio shell in the literature [ 23 ], and rearranging, Eq. 3

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Journal of Thermal Analysis and Calorimetry
Authors: Saheli Ganguly, Kausik Dana, Tapas Kumar Mukhopadhyay, and Sankar Ghatak

series of Ca-smectites and concluded that dehydration followed a first-order reaction with activation energy values ranging from 39.8 to 52.3 kJ mol −1 . Furthermore, Guler and Sarier [ 29 ] arrived at a value of 14.72 kJ mol −1 for a similar type of

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) analysis. According to the TG data, the kinetic parameters of thermal decomposition of materials such as apparent activation energy ( E a ), pre-exponential factor ( A ), and apparent reaction order ( n ) can be calculated using various kinetic models such

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investigated the kinetics of mullitization, all reporting that mullitization occurs by nucleation-growth mechanisms. Okada [ 3 ] summarized the activation energy values for mullitization from various starting materials (such as diphasic gel, monophasic gel

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