Pericak-Spector, K.A.Williams, W.O.2007-08-162007-08-161983https://hdl.handle.net/11299/4865In recent years workers in mixture theory have become aware of the central role that volume-fraction, the parameter describing the relative proportion of the volume occupied by a constituent, must play in that theory. In particular, the rate of change of volume-fraction, which we here call the chority, must appear in a working term as contributing to the energy, in order to avoid various inconsistencies. This is true both in theories in which volume-fraction appears as a parameter of microstructure and in complete mixture theories.