Profiles, noncoherent

A simple example may serve to illustrate the development of a noncoherent profile, the use of the composition-path concept in predicting the behavior even of noncoherent systems, and the physical factors re-... 

The key concept of the theory is that of coherence. If one allows completely arbitrary concentration profiles of the species, one will usually find that the species concentrations coexisting at any given time and location in the column have different velocities. Compositions then exist only momentarily, as their constituent concentrations advance at different rates and thus part company. Composition profiles with this property will be called noncoherent. In contrast, a profile will be called coherent if, at a given time, all concentrations coexisting at any location have the same velocity, so that compositions remain conserved as they migrate. 

---