/ Instructions /
                    

                    

                      1. Load thermal analysis data. The input file can be created with 
                      import
                       app or manually. It should be the single file with the rows of equal length, four rows for each experiment, i.e.,
                        (i) temperature [°C], (i+1) time [s], (i+2) conversion degree [0..1], (i+3) conversion rate [1/s], 
                        , separator - space. Example can be found 
                      here
                      . Note, that more than four experiments is needed to perform the kinetic analysis (see the 
                      ICTAC Kinetic committee recommendations
                      ).
                    

                    
2. Press "Calculate" button. The range of conversion degree values that used in calculations can be 
                        adjusted defining α-min, α-max and the step dα (by default the 0.05..0.95 range is set to eliminate the minor effect of the baseline selection). 
                        Check the accuracy of the isoconversional analysis - 
                        correlation coefficient (R^2) in case of the Friedman method or the optimization indicator (Ω) for the advanced Vyazovkin method.
                        Note, that while the first value has to be close to unity, the latter should approach the n(n-1) value (where n is the number or experiments).
                         Additionally, the results of the Kissinger method can be shown on the plot and in text from
                          (consider it only as a first estimation, not the as final result!). The results of both isoconversional methods, i.e., the differential Friedman
                          and integral advanced Vyazovkin, can be plotted together for visual comparison.

                    

                      3. Finally, use the "Export results" button
                          to generate the text file with the results of the selected isoconversional method. This file can be used later for thermal 
                      prediction.
                    

                  

                

              

            

          

          

            

              
              
            

          

          

            

              
              
            

          

          

            

              
              
            

          

          

            

              
              
            

          

          

            

              
              
            

          

        

        

          

            

          

          

            

          

          
          

            
Isoconversional differential Friedman method [1]

            
$$ \large \bbox[white] 
                 {
                 ln\left(\frac{d\alpha}{dt}\right)_{\alpha,i} = ln[f(\alpha) A_\alpha] - \frac{E_\alpha}{RT_{\alpha,i}}
                 }
                 $$

          

          

            
Advanced integral Vyazovkin method [2]

            
$$ \large \bbox[white] 
                 {
                 \Phi(E_\alpha) = \sum_{i=1}^n \sum_{j \neq i}^n \frac{J[E_\alpha,T_i(t_\alpha)]}{J[E_\alpha,T_j(t_\alpha)]}\;,
                 }
                 $$
                 

            
$$ \large \bbox[white]
                   {
                   \quad J[E_\alpha,T(t_\alpha)] = \int_{t_{\alpha-\Delta\alpha}}^{t_\alpha} exp\left[\frac{-E_\alpha}{RT(t)}\right] dt 
                   }
                   $$

          

          

            
Kissinger method [3,4]

            
$$ \large \bbox[white] 
                 {
                 ln\left(\frac{\beta_i}{T_{p,i}}\right) = ln\left(\frac{AR}{E_a}\right) - \frac{E_a}{RT_{p,i}}
                 }
                 $$

          

          
References:

          

            
1. Friedman, H. L. Kinetics of Thermal Degradation of Char-Forming Plastics from Thermogravimetry. 
                  Application to a Phenolic Plastic. J. Polym. Sci. Part C Polym. Symp. 1964, 6 (1), 183–195. DOI:10.1002/polc.5070060121

          

          

            
2. Vyazovkin, S. Modification of the Integral Isoconversional Method to Account for Variation in the 
                  Activation Energy. J. Comput. Chem. 2001, 22 (2), 178–183. DOI:10.1002/1096-987X(20010130)22:2<178::AID-JCC5>3.0.CO;2-#

          

          

            

              3. Kissinger, H. E. Reaction Kinetics in Differential Thermal Analysis. Anal. Chem. 1957, 29 (11), 1702–1706.
              

              4. ASTM E698-05, Standard Test Method for Arrhenius Kinetic Constants for Thermally Unstable Materials, ASTM International, West Conshohocken, PA, 2005. 10.1520/E0698-11.
            

          

          

          
          

            Dr. Nikita V. Muravyev, Version 31.10.21
          

          

            

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