We have produced52Fe to be used for the scintigraphy of bone marrow. The natural chromium electroplated onto copper plates was irradiated by the 38 Me V3He internal beam from the IMS cyclotron at 20-30 μA for 2-3 h. The52Fe yield from thick chromium target ranged 0.7-1.3 MBq/μA·h at the end of bombardment (EOB) . The irradiated chromium was dissolved in hydrochloric acid and about 90% of52Fe was prepared as ferric citrate after the chemical separation based on the extraction with diisopropyl ether. The contents of impurity elements and long-lived radio-nuclides were measured. The specific activity was 0.6 MBq/μg Fe and the relative content of52Fe was 0.06% both at EOB. The results suggested the possible use of the produced52Fe for medical use, though further investigations are necessary. The 169 keV γ-ray images of a rabbit taken with a scintillation camera at 0.5 and 16 h after intravenous injection of the prepared52Fe pharmaceutical are presented.
An analytical method for uranium and the results of measurement of238U and234U in river waters on the eastern area in Japan are described in this report. The mean values of the concentration of238U and of the activity ratio of234U/238U in 27 sample waters were 0.27 mBq/l and 1. 55, respectively. The unexpected234U/238U ratio, which was more than 2.0 in the range, was found in some waters. In general, as the activity ratio of234U/238U is low in surface water and high in deep aquifer, it was supposed that these river water may contain much amount of spring water from the mountain area.
Since the ripening process of the rape plant pod has not been studied well, non-destructive analysis of the pod has been carried out by neutron radiography. From the water distribution in the pod, the formation of pod parenchyma as well as vascular system were clearly observed. During the ripening process of the pod water content and weight of the seed were measured. It was found that at the early stage of the ripening process the water content of the seed became maximum and began to decrease, whereas the weight of each seed was gradually increased throughout the ripening process. Neutron radiography, which shows the water content of the pod, will give the clue to the decreasing the water content of the seed from the middle of the ripening process.