Solving Multiple First Order Differential Equations for Constants

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HK 2019-2-15

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评论： Torsten 2019-2-20

采纳的回答： Torsten

Hi,

I hope someone can help me.

I am looking to solve these 6 first order differential equations for the unknowns k1, k2, k3, k4, k5 and k6, with known concentrations in the square brackets (any number for them will do just now to get a working script!). Could someone help me obtain a script to do this?

Many thanks in advance.

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Torsten 2019-2-15

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Replace the time derivatives by difference quotients.

Then you get a linear system of equations

A*[k1;k2;k3;k4;k5;k6] = b

where the number of rows in A is equal to (6*number of measurement times).

This can subsequently be solved using

k = A\b.

Best wishes

Torsten.

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HK 2019-2-20

Yes, I have concentration data at the end of the reaction (t=60 mins/3600s) and also at two intermediate times (t = 2 mins/120s and t = 12 mins/720s). Should I state all of these values at the top of the script like I did for the values at t=0? Should the script then run or do additional changes need to be made in its layout?

Thanks again!