الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present study reveals a deep association between the effects of gamma rays in the irradiated organic substances and the age of the material after exposure. The late effects of radiationinduced modifications in the polymeric material were investigated by means of the infrared signature and correlation with ultraviolet absorption. Detectors made of poly (allyl diglycol carbonate) were irradiated with doses between 500 Gy and 5 MGy and compared by means of similar samples aged 8 and 12 years. Infrared investigation showed the differences between infrared spectra recorded directly after irradiation and those recorded for the aged samples.
The aging effect was found to be minor at low doses. For samples irradiated at high doses, the material digested itself through processes that have radiation breeding-fermentation behavior.
Ultraviolet absorption revealed the presence of a hyperchromic effect (an increase in the intensity) and a bathochromic shift (a red shifting towards the longer wavelength with low energy) in connection with the age of these samples. This breeding behavior of radiation-induced effects in organic materials should be taken into account in dosimetry.
The formation of highly oxidizing radicals in multifunctional-solid compounds upon irradiation with gamma-ray had been investigated. Five organic compounds having a single carbon
ring had been used in the present investigation as:
1-chloro-4-nitrobenzene, 4’-aminoacetophenone, 3’-hydroxyacetophenone, n-anthranilic
acid and triphenylmethane.
These materials were irradiated using 60Co radiation with different doses between 20 kGy and 100 kGy. Electron spin resonance spectroscopy spotted increases of the resonance absorption having
landé factor around 2.0113±0.003 upon irradiation with the increasing dose. This resonance absorption was related to the formation of long-lived oxygen radicals that were attached to one of the radiation synthesized compounds. The method of infrared absorption spectroscopy emphasized the formation of cyclic and aliphatic hexane in addition to the active oxygen radicals.
n-Anthranilic acid was found to be suitable for radiation the dosimetry with long-lasting
radiation signature as electron spin and also to determine the exposure dose. The time-lapse infrared and electron spin resonance measurements had been used to tracked the formation of active species
within the time-lapsed after the end of exposure; results showed that the dosimetric signature may be used as a tracker for the time when the exposure happens.