الفهرس 
General IntroductionOnly 14 pages are availabe for public view
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Abstract
Due to the use of rather costly enriched tellurium target materials it was intended in the present work to study a new route by using antimony as a target. Excitation functions of the reactions natSb(gas,xn)123,124,125,126I and 121Sb(gas,xn)123,124I were measured from their respective thresholds up to 26 MeV, and of the reactions natSb(3He,xn)124,123,121I up to 35 MeV, with particular emphasis on data for the production of the medically important radionuclide 124I. The conventional stackedfoil technique was used, and the samples for irradiation were prepared by a sedimentation process. The measured excitation curves were compared with the available data in the literature. from the experimental data the theoretical yields of the investigated radionuclides were calculated as a function of the alphaparticle and 3Heparticle energies. The calculated yields of 124I from the natSb(gas,xn)124I and 121Sb(gas,n)124I reactions over the energy range Ega ? s22 13 MeV amount to 1.02 MBq/(So(BAh and 2.11 MBq/(So(BAh, respectively. The yield of 124I over the energy range = 35 13 MeV amounts to 0.95 MBq/(So(BAh . Production of high purity 124I was possible through the 121Sb(gas,n) reaction using a highly enriched antimony targets (> 99 %) and allowing a decay time of about 5 days prior to application. The batch yield at 28 MeV gasparticle energy, 10 A beam current and 10 h irradiation time was found to be 100 MBq. This yield is still rather low for practical application. Radioiodine and radiotellurium were strongly retained on the anion exchanger Amberlyst 21b using 7M HCl. About 97% of antimony was eluted by washing the column using 100 ml of 7M HCl, then 20 ml of 5mM tetrabutyl ammonium bromide (TBAB) in ethyl acetate solution with a few DROPs of sodium meta bisulphate were sufficient to elute more than 95 % of the carrier free 124I. Three quality control tests have been carried from which the following results were achieved.1) 125I and 126I impurities were found to be less than 0.2 % at 5 d after EOB. 2) More than 99% of the radioactivity was found to be in iodide form. 3) Using ICP the Sb concentration was found to be less than 8 ppm.