Impulse response FIA

Figure 2.11. The impulse response and the step response obtained in a single-line FIA system by injecting a dye solution of concentration C into an inert colorless carrier stream, the signal being recorded as absorbance A. 5 is the point of injection and 5i/2(ti/2) is sample volume (time) necessary to inject sample volume to reach = 2. Vr is the reactor volume, T is the residence time, and D is the dispersion coefficient. [608].

For process control applications, FIA offers the benefit of real-time continuous monitoring by regularly aspirating sample solution (e.g., from a batch-type chemical reactor) into a carrier-wash solution, the detector of choice being operated in an impulse response mode. Thus a chemically modulated signal, continuously recorded as a series of peaks (injected material on a constant background of carrier-wash), offers a positive... 

Introduction of an automated, well reproducible rigorous testing procedure which would allow critical testing of chemical sensors should become a powerful tool for sensor development. There is increasing experimental evidence that FIA is suitable for sensor and material testing by means of the impulse-response technique. ... 

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