Fig. 4

Kinetic analysis for bloodstain compositions. The scores corresponding to the first (a, b) and the fourth (c, d) spectral components via multivariate curve resolution-alternating least squares were applied to the curve fitting for respective kinetic models. a, c Represent the observed scores (circles) for one of the three donors and the fitted kinetic equations (solid lines) for 30 °C (dark magenta and dark turquoise), 24 °C (magenta and turquoise), and 16 °C (light magenta and light turquoise). The rate constants yielded at each temperature are represented by diamonds in b, d. The dashed lines indicate the results of line fitting using the Arrhenius equation (Eq. (4))