Kissinger model

Modeling the vulcanization of liquid silicone rubber (LSR). Lopez et al. [28, 29] modeled the vulcanization of liquid silicone rubber using dynamic DSC tests. In order to do this, the Kissinger model [25, 26] and the Kamal-Sourour model were used to determine kinetic parameters that fit the experimental data. The idea is to generate a single set of parameters that accurately models the used scanning rates of 1,2.5, 5, and 10 K/min. 

In order to obtain a physical energy of activation, E, the Kissinger model [25,26] was used. This model uses an nth-order expression to model the kinetic reaction defined as... 

The two most popular methods of calculation of energy of activation will be presented in this chapter. First, the Kissinger method [165] is based on differential scanning calorimetry (DSC) analysis of decomposition or formation processes and related to these reactions endo- or exothermic peak positions are connected with heating rate. The second method is based on Arrhenius equation and determination of formation or decomposition rate from kinetic curves obtained at various temperatures. The critical point in this method is a selection of correct model to estimate the rate of reaction. 

In order to find a unique set of parameters for all rates, Lopez et al. proposed that the activation energy E is determined through Kissinger s model, which is implemented to mathematically determine the other five parameters for the Kamal-Sourour model. The activation energy, E2, is fitted as a constant, while the four remaining parameters,... 

The TPR patterns are very sensitive to the value of the activation energy which is needed for the modelling. Fortunately, this can be calculated separately from a series of experiments in which the heating rate is varied. Kissinger introduced this method in DTA measurements. It will be shown that this method can be generally used in TPR modelling. For the maximum of the TPR peak the following equations hold ... 

Because (1 - is a constant for a given value of n, a value for 7i, may be obtained from the slope of a plot of ln(/ /r , against l/r ,ax for a series of experiments at different heating rates, ft,. Augis and Bennett [65] modified the Kissinger treatment for use with the Avrami - Erofeev (or JMAEK) model (An). They plotted - TJ) against l/7] ax where is the initial temperature at the... 

Dunker AK, Lawson JD, Brown CJ, Williams RM, Romero P, Oh JS, Oldfield CJ, Campen AM, Ratliff CR, Hipps KW, Ausio J, Nissen MS, Reeves R, Kang CH, Kissinger CR, Bailey RW, Griswold MD, Chiu M, Gamer EC, Obradovic Z (2001) Intrinsically disordered protein. J Mol Graph Model 19 26-59... 

As can be seen, with the exception of the R3, D3 and D4 models, the exclusion of the In (j)m (o max term in the generalized Kissinger equation (9) has less than a 3% effect, and for the simple n order and Avrami-Erofeev models, A2, A3, less than a 1% effect. Similar figures result if one sets m - h or m = 1 in the rate equation (1). As the Arrhenius exponent E/RTjjjqx increases, there is a gradual small increase in Umax models. For all n order and diffusion controlled... 

The Kissinger equation, when expressed in its modified form (9) is a general thermoanalytical expression, applicable to a wide range of kinetic models. In the absence of other criteria, the value of ot ax assist in indentifying the... 

Kinetic analysis according to the model-free approach by Kissinger-Akahira-Sunose [25, 26] was performed with the computer program Excel. For kinetic analysis according to the advanced Vyazovkin method [27], the STAR software... 

The physicochemical phenomena of RPIPC, the basis for the retention mechanism, are still not fully understood. This mechanistic uncertainty is reflected by the many terms proposed for this kind of separation method in the past Here, we discuss two hypotheses, although both of them lack an unequivocal experimental basis. Horvath et al. [6,7] take the view that solute ions form neutral ion pairs with the hpophilic ions in the aqueous mobile phase. These neutral ion pairs are retained at the nonpolar stationary phase. In contrast, Huber et al, Hoffmann and Liao, and Kissinger [8-10] support the ion-exchange model, where the hpophihc reagent first adsorbs at the surface of the stationary phase. 

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