Question

Q2: Fricke dosimeters
First case
A Fricke solution yields an optical density of 1.2.

1. a) What is the percentage of light transmitted through the Fricke solution?

2. b) Calculate the concentration of ferric ions assuming that the molar extinction coefficient

   is 2174 M-1cm-1 at 25 degree C in a cuvette 1cm thick.

Second case

One liter of Fricke solution at 25 degree C is irradiated by 1MeV electron beam collimated to an aperture of 2cm in radius for 1 minute.

If the variation of optical density is 0.125 at 304nm in a 1cm long cell, what was the energy fluence rate at the aperture?

Assume a weighted yield ???(??3+) = 3.517 ??2?−1 and neglecting backscattering. Density of Fricke solution is 1.0227.10-3 kg.cm-3.

Answer 1