estimated based on the zpc and log(*)K°(M+) (see article); equilibrium constants in this study refer to site-occupancy standard state with hypothtical 1.0 M ionic strength (K°) and values for N' = 10 * 10^18 m^-2 and A' = 10 m²/g using the equation: K = K°(Ns * As/N' * A'), where Ns represents the SSD = 4.6 sites/nm² from [K94d] and As the SSA = 388 m²/g from [K94d]; parameters predicted from equations in [S05]; pH(ZPC): theoretically predicted value [S05]