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The DLC/Kapton structures irradiated with 60 Co γ-rays at doses to 1 MGy have been studied by measuring transmission and attenuated total reflection (ATR) spectra. It has been shown that there are significant changes in the spectra in the ranges of vibrations of О-Н, CH 2 , and CH 3 bonds due to radiationinduced processes in the byproducts of polyimide synthesis and residual solvents. Significant differences were found in the radiation-induced processes occurring in the bulk and near-surface region of a polyimide film and DLC/polyimide structures. After irradiation, the bulk of polyimide exhibited bands due to asymmetric and symmetric vibrations of the CH 3 group. Bands associated with the vibrations of the CH 2 group were additionally observed in the near-surface region. The formation of CH 2 groups in the near-surface layer under irradiation was more pronounced in DLC/polyimide structures than in polyimide films; this was due to the additional supply of hydrogen from the DLC film.

FP-9120 positive photoresist films 1.8 μm thick implanted with boron and phosphorus ions deposited onto the surface of KDB-10 single-crystal (111) silicon wafers by centrifugation are investigated by their conductivity and electron spin resonance measurements. It is shown that the Р + ion implantation leads to the formation of a layer with an electronic conductivity of about 10 −9 Ω −1 cm −1 . At a phosphorous implantation dose of 6 × 10 15 cm −2 , the electron spin resonance spectrum contains a narrow isotropic line with a g factor of 2.00654 and a width of 3.83 G, which is most likely related to the formation of phenoxy radicals. As the implantation dose increases to 1.2 × 10 16 cm −2 , a line with a g factor of 2.00264 and a width of 3.96 G is detected in the electron spin resonance spectrum, which is caused by unpaired electrons delocalized according to the π-polyconjugated system.

In the present study the distribution of long-lived radionuclides between the drug product, recovered water [ 18O]H2 O and solid phase extraction cartridges was studied in [18F]fluorocholine production process. Isotopic composition for long-lived nuclides (half-lives = 10–312 days) was determined, the mechanisms of their formation and accumulation on cartridges are considered. It was shown that in the batches of pharmaceutical produced the content of long-lived nuclides is by 5 orders of magnitude lower than the limit value specified by the appropriate 07/2016:2793 European Pharmacopoeia article. The results obtained are of vital importance for optimization of the procedures for radioactive waste management in the production of [18F]fluorocholine using IBA Cyclone 18/9 HC cyclotron and, consequently, for minimization of radiation exposure of personnel.