Limitations on non-steady-state kinetic behaviour imposed by the reaction mechanism

4 LIMITATIONS ON NON-STEADY-STATE KINETIC BEHAVIOUR IMPOSED BY THE REACTION MECHANISM 

This is a general fact. For monomolecular (or pseudo-monomolecular) reactions the graphs corresponding to compartments are acyclic. A similar property for the systems having either bi- or termolecular reactions is more complex. It can be formulated as follows. If every edge in the graph of predominant reaction directions for some compartment is ascribed to a positive rate constant k and chemical kinetic equations are written with 

At t - oo we will obtain a non-reactive mixture of N2 and N4. A graph of the predominant directions corresponds to the direction of the conversion of the initial components either into one substance or a mixture of non-reactive components. 

The other way to describe this property is as follows. A convex envelope for the multitude of stoichiometric vectors for the edges in the graph of predominant directions written as if they were direct reaction steps does not contain zero, i.e. there are no such non-negative Alt. . Aq as 

It can also be interpreted in terms of the bipartite graph for the reaction mechanism (see Sect. 1.3). 

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