Figure shows the data that was derived for the case of MgSO 4 solution at the three chosen frequencies: 0.5 THz (lower bound), 1.0 THz (high signal to noise ratio), and 1.6 THz (centre of the crystalline peak) at a temperature of 5 °C. The measurements were performed under static as well as continuous flow, and no significant deviation was identified between the different conditions, as demonstrated by the red data points in Figure which correspond to the continuous flow conditions.