We further compare the retardation power of the acids by calculating the difference between the time of the heat flow maximum of the acid-containing sample and the reference sample (Figure ) and refer to this difference as retardation time. ) for H 3 PO 4 is indicated by the dashed line. The parameter a and b were determined to be 1.96 min and 1.58 × 10 -2 g CAC /µmol, respectively. The lines for the other salts serve as a guide to the eye.