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Kinetics and mechanism of non-isothermal dehydration of nickel acetate tetrahydrate in air

“…The dependence of E a on a obtained from isoconversional method assists in both detecting multi-step processes and drawing certain mechanism conclusions [12]. The activation energies calculated with isoconversional methods act as initial values for multivariate non-linear regression process [16].…”

“…Multivariate non-linear regression is based on multiple heating rates, and makes the assumption that the parameters of the model are identical for measurements at all heating rates [15,16]. It allows a direct fit of the model to the experimental data without a transformation, which would distort the error and consequently the result.…”

“…The relevant differential equations are numerically solved and the parameters of the differential equations are iteratively optimized. Compared to the single curve analysis, the quality of fit diminishes considerably for the non-applicable reaction types [15,16]. So the distinguishability between the individual reaction types improves drastically, and the 'correct' reaction type is significantly recognized and the kinetic parameters apply.…”

Linear Addition Polymers and Cyclic Oligomers ofN,N-Diglycidyl Aniline and Amines. Uncrosslinked Epoxide-Amine Addition Polymers, 46

“…[23] The stoichiometric reaction mixtures were filled into pans suitable for volatile samples and kept in liquid nitrogen until measurement. Single heating curves or single isothermal reaction curves are useless for a kinetic analysis, [24,25] therefore we always used 5 different heating rates between 0.25 and 4 K N min -1 and some additional isothermal measurements. The kinetic modeling by means of multivariate non-linear regression was carried out using the software "Netzsch Thermokinetics" [24] and by the newly developed software "Component kinetics".…”

“…Single heating curves or single isothermal reaction curves are useless for a kinetic analysis, [24,25] therefore we always used 5 different heating rates between 0.25 and 4 K N min -1 and some additional isothermal measurements. The kinetic modeling by means of multivariate non-linear regression was carried out using the software "Netzsch Thermokinetics" [24] and by the newly developed software "Component kinetics". [26] Analytical Measurements M -n values were determined from vpo measurements using a Knauer osmometer in N,N-dimethylformamide at 37 8C.…”