In the determination by activation analysis of rare earth elements contained in river and sea water, a simple chemical group separation made it possible to determine La, Ce, Sm, Eu, Tb, Dy, Tm, Yb and Lu by γ-ray spectrometry using a Ge (Li) detector. The contents of these rare earth elements in sea water of Tokyo Bay and in T ama River which flows through Tokyo City into the bay were determined by the above-mentioned method. The distribution pattern of these rare earth elements expressed by chondrite normalized pattern for the sample waters showed that there is characteristic difference in the pattern between river and sea water. And when these patterns are compared with that of ocean water, the pattern of sea water has intermediate characteristics between those of river and ocean water.
A rapid and nondestructive determination of oxygen, fluorine, and aluminum in aluminum electrolytic bath was studied by the use of 14 MeV neutron activation, together with the flux monitoring and the calculation of the photo peaks in the presence of nonlinear backgrounds. A standard sample (AlF3) for the flux monitoring and an unknown sample were irradiated under neutron fluxes of 3.3×106n/cm2/sec and 1.3×107n/cm2/sec, respectively, both for about 100 seconds. The following reactions and radiations from the products were used: 16O (n, p) 16N, 4-8 MeV β and γ rays 19F (n, 2n) 18F, 0.51 MeV annihilation photon 27Al (n, p) 27Mg, 0.84 MeV γ rays. The photo peak counts and the concentrations of oxygen, fluorine, and aluminum were calculated with a computer. Fluorine in the monitor (Al F3) was used also as the oxygen standard, because the19F (n, α) 16N reaction gives16N as well as does the16O (p, n) 16N reaction. The relative standard deviations were about 3% for fluorine and aluminum, and about 6% for oxygen. It took about 17 minutes for the determination including the irradiation and measurement.
After treating with fixative containing picric acid, the squash preparation by Feulgen staining was made for the shoot apical meristem of germinating rice seeds. The first cell cycle in the cells of the meristem was determined with3H-thymidine autoradiography. Radiation mutagenesis at the cellular level was also discussed.
Affinity of gold and bismuth for the malignant tumor was examined;, using the rats which were subcutaneously transplanted with Yoshida sarcoma. And the relations between the uptake ratio into the malignant tumor and the binding capacity to the protein were investigated in the various compounds of mercury, bismuth, gold, gallium, indium, scandium and zinc. The compounds of gold and bismuth had strong affinity for the malignant tumor as well as for the kidney. This nature of gold and bismuth for the malignant tumor and the kidney was very much similar to the nature of Hg-compounds for the malignant tumor and the kidney. The binding capacity to the protein was approximately in proportion to the uptake ratio of the compounds of mercury, gold, and bismuth into the malignant tumor. But in the uptake of the compounds of gallium, indium and scandium into the malignant tumor, the binding capacity to the protein did not seem to play an important part. There was a group of the compounds in which the binding capacity to the protein was weak and the uptake ratio into the malignant tumor was small, but there was no compound in which the binding capacity to the protein was strong and the uptake ratio into the malignant tumor was small.