Mathcad-how to fit and optimize two objective functions

[BH_10642669]

Hi guys, I`m a student major in chemistry. Recently, i`m confused this this interpretation, The equation"The method proposed here for determining the kinetic parameters is a multistage procedure. First, the Pearsons linear correlation coefficient between the left-hand side of eq 15 and the reciprocal of temperature is used as the objective functionfor optimization, where n and m are the variable parameters to maximize the objective function. Here, optimization has been performed by means of the maximize function of Mathcad software (Mathsoft inc.). By this optimization procedure, the n  and m parameters that yield the best linear correlation for the plot of the left-hand side of eq 15 versus the reciprocal of temperature are obtained".  The equation is shown below. So I was wondering how can I implement this derivation through Mathcad.

[terryhendicott]

Hi,

Need some data to work with.

Can you tell us the paper that the quotes come from?

Cheers

Terry

[BH_10642669]

Thanks for you reply, the paper was titled Combined Kinetic Analysis of Solid-State Reactions: A Powerful Tool for the Simultaneous

Determination of Kinetic Parameters and the Kinetic Model without Previous Assumptions on the Reaction Mechanism from https://pubs.acs.org/doi/10.1021/jp064792g#

[terryhendicott]

Hi,

Downloaded the paper thank you.

Proposing an alternative strategy to multiphase process of optimizing for maximum Pearson's linear correlation coefficient used in the paper.

Prime has a general purpose curve fitting function called genfit() that can fit any function with any number of parameters to x and y data modelled or experimental.

Function genfit() easily produces the model equations parameter c, n, & m values from Table 1 of the paper

Cheers

Terry 

[BH_10642669]

It`s very kind of your detail answer about the fitting of the model function in Tabel 1 by the useful genfit(). In fact, i`m more interested in the Pearsons linear correlation coefficient between the left-hand side of eq 15 and the reciprocal of temperature. For a decomposition reaction, a represents the convesion of the reaction and the a, da/dt, T could be measured by instrument. To obtain the E and A of the reaction, the author of the paper conducted the above equation 15. In his viewpoint, the left of equation 15 is linear with the 1/T, so  we can change the parameter of n and m until the value of the left of equation 15 has the best linear correlation with 1/T.  Thus, n and m was obtained. And i`m confused how to do it through Machcad.

[ValeryOchkov · Accepted solution]

My old book is now open

Chemical Kinetics with Mathcad and Maple | SpringerLink