Living organisms and thermodynamics (Pentcho Valev)

Lukasz Salwinski lukasz at
Sat Oct 18 09:30:56 EST 1997


>Please tell me what you accept and what you don't.

>1. The electrical double layer at a Donnan membrane is capacitor-like.

capacitor-like - yes
exactly like capacitor - no

there's more to Donan system than capacitor formed by the membrane
there are charged ions swimmin' 'round on both sides. 

>2,3, etc
>   What I have written about a finite-sized capacitor in a vacuum cannot
>be doubted. However I am not at all sure to what extent this analogy is

not valid at all - it misses a large part of the system - ions.

the system has only limited similarity to capacitor. 
you're trying to make your argument look like flat capacitor
filled with a nonconducting dielectric and separating 
two solutions is supposed to work the same like a donnan
system. utterly wrong.

do your reading. there's a large number of reviews on the subject
(ie on the electrostatics of membrane systems). 

>Obviously a special experiment is needed, and I hope one day it will
>be done.

the exeriments were done. I've already gave you pointers. do your reading.


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