  With the chiral susceptibility criterion we obtain the phase diagram of
strong-interaction matter in terms of temperature and chemical potential in the
framework of Dyson-Schwinger equations (DSEs) of QCD.After calculating the
pressure and some other thermodynamic properties of the matter in the DSE
method, we get the phase diagram in terms of temperature and baryon number
density. We also obtain the interface tension and the interface entropy density
to describe the inhomogeneity of the two phases in the coexistence region of
the first order phase transition. After including the interface effect, we find
that the total entropy density of the system increases in both the
deconfinement (dynamical chiral symmetry restoration) and the hadronization
(dynamical chiral symmetry breaking) processes of the first order phase
transitions and thus solve the entropy puzzle in the hadronization process.
