A new method of radon measurement - absorptive polymer dissolved liquid scintillation counting

摘要

A new method of radon measurement, absorptive polymer dissolved liquid scintillation counting, was developed. A polystyrene foam absorber which absorbed radon was dissolved in liquid scintillator, and the radioactivity was measured. This measurement has merits in that, (1) a solid state absorber has no chemical hazard, and is easy to treat, (2) the absorber itself is easily dissolved in liquid scintillator, and maintains ideal condition for liquid scintillation counting. The measurement will be available for liquid state or gas state. The time to reach equilibrium was 24 hours for a cross section 10×10 mm polystyrene foam. Absorbed radioactivity was proportional to the mass of polystyrene foam and to the partial pressure of radon. Absorbed radon activity of polystyrene foam was 130 fold that of water, or 2.6 fold that of toluene. Although the accuracy is less than the toluene extraction method, quantitative measurement is suitable' not only to radon but to other radioisotope gases.