Title of article :
New approximate formula for Arrhenius temperature integral
Author/Authors :
Wanjun Tang، نويسنده , , Yuwen Liu، نويسنده , , Hen Zhang، نويسنده , , Cunxin Wang، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2003
Abstract :
In this paper a more precise approximate formula for Arrhenius temperature integral, i.e., −ln P(u)=0.37773896+1.89466100 ln u+1.00145033u, is proposed, by using two-step linearly fitting process: (i) the linear dependence of d ln p(u)/du on 1/u and (ii) the linear dependence of (ln p(u)−c ln u) on u. Values of p(u) at different u were directly obtained from numerical integration of temperature integral without derivation from any approximating infinite series, and values of d ln p(u)/du were obtained by numerical differentiating. New equation for the evaluation of non-isothermal kinetic parameters has been obtained from the above dependence, which can be put in the form lng(α)T1.89466100=lnAEβR+3.63504095−1.89466100 ln E−1.00145033ERT The validity of this formula was confirmed and its deviation from the values of numerical integrating was discussed. Compared with some previously published approximate formulae, our formula has the best result in the kinetics analysis of non-isothermal process.
Keywords :
Non-isothermal kinetic analysis , Temperature integral , TGA
Journal title :
Thermochimica Acta
Journal title :
Thermochimica Acta