Abstract
Nuclear track microfilters prepared by irradiating CN-85 cellulose nitrate detectors with 252Cf in 2 π geometry were given post-irradiation thermal annealing and ultraviolet treatments followed by etching. These filters were employed to investigate the diffusion of radon. Alpha particles produced due to the decay of radon and its daughters were registered and etched electrochemically in lexan polymeric detectors. Experimental findings have led to determine diffusion coefficient and activation energy for diffusion through various filters/membranes. Diffusion coefficient of radon through the filter treated with UV from the laser is (1.8±0.05) 10-4 cm2 sec-1 , being a maximum value as compared to other filters and membranes. Corresponding activation energy for diffusion bears a minimum value of (0.018 ± 0.001) eV for this filter. It can be speculated that the post-irradiation laser exposure modifies the profiles of the pores which reduce the resistance to the flow of radon.