Figure 3
Heater response curves as measured (left) by the heater and (right) by a thermocouple inside the tube, in 50 K increments from 373 to 673 K at the sample. The PID settings were chosen to reach a flat plateau quickly at the desired reaction temperature inside the tube, taking the offset between the measured air temperature at the heater nozzle (left) and at the beam position inside the tube (right) into account. The dashed vertical lines are placed at t = 0 and 5 s. |