COLORIMETRIC TITRATION METHOD AND APPARATUS

摘要

The titrating apparatus comprises radiant energy means (35, 40 and 45). The device includes means (15) for modulating an amplitude of an intensity of the radiant energy. An adjacent solution within a sample beaker (50) having a color indicator dissolved therein partially absorbs the radiant energy. A radiant energy detector (65) produces a transmitted signal. Filtering means (70) filters the transmitted signal. The filtering means produces a filtered transmitted energy signal representative of only the amount of radiant energy transmitted through the solution from the radiant energy source, free of other sources of radiant energy. The colorimetric titrator also includes means for constructing a titration curve (85), means for computing the first derivative of the titration curve, means for computing the second derivative of the titration curve, control means (10) for controlling titrant addition means in response to the first derivative of the titration curve, and means for calling the endpoint of the titration by using the second derivative.