SSNTD'S AND SOME OF ITS APPLICATION IN SOME NATURAL MATERIALS

Abstract

Studying of radiation dosimeter has grown rapidly in recent years. Different techniques have been proposed and the etched nuclear track one is proved to be applicable in various fields of radiation measurements. The solid-state nuclear track detector, CR-39 polycarbonate track detector was found to own unique properties determined by the chemical and physical structure of CR-39 polycarbonate. This plastic has been successfully applied to record nuclear charged particle Z/-values from 6 to 100 and is found to have wide applications in different fields of dosimetry, spectroscopy and environmental science due to.its .high .>ensitivity. Also, its application has been extended to autoradicgraphy of radioactive mineral.

This thesis includes the historical and basic iaformation concerning the interaction of charged particles with :natter and living organs. The track formation models and the etchable track fonnation criteria were discussed, the track etching methodology and the etched track parameters.

The experimental part deals with the preparation of solid state nuclear track detector samples used in this work, CR-39 (poly ally diglycol carbonate), which is pre-etched chemically in 6N NaOH + 40% C2H5 OH at 60 °C for 6 hours to reduce the background alpha tracks from the environmental radon. In the first part, three pieces of CR-39 were inserted in each tube of blood samples, either smoker or non-smoker, and then stored at (-20 °C) for 12 weeks.

Our results reveal that the level of the registered average alpha activity (Bqlkg) in the male of smoker blood is 6.42 and 3.75 times higher than that of non-smokers and 3.12 time> in case of female.