2ND-ORDER CALIBRATION BASED ON ALTERNATING TRILINEAR DECOMPOSITION - A COMPARISON WITH THE TRADITIONAL PARAFAC ALGORITHM

Quantitative analysis of p-chlorotoluene in the presence of o-chloroto luene as an interferent was attempted by using HPLC with diode array d etection and second-order calibration methods. An emphasis was placed on a further comparison between two methods, i.e., the traditional par allel factor analysis (PARAFAC) and the alternating trilinear decompos ition (ATLD) methods. The following conclusions have been confirmed fo r the calibration examples tested. PARAFAC does not always converge to chemical meaningful solutions and its convergence rate is slow for th e. This seems to be owing to the deficiency of a real trilinear sense in PARAFAC. The convergence rate of the ATLD algorithm is extremely fa st. The ATLD-based calibration not only retains the advantage of secon d-order calibration but can give satisfactory concentration prediction s.