Weisz modulus Practical useful quantity

Recall that for calculating the Thiele modulus, knowledge of the rate constant is needed, which requires elaborate kinetic studies under conditions free of diffusional effects. A practically more useful modulus based on observable quantities can be obtained by recasting Thiele modulus in the form 

This modulus is named after Weisz who first proposed it along with Prater in 1954 and can easily be prepared from the more common e- j) plot. 

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