The rate constants for thallium(I)-thallium(III) exchange with various alcohols in sulfuric acid solution were determined. In all cases involving alcohols, methanol, ethanol, 2-propanol, 2-methyl-2-propanol, the reaction rates were not accelerated. The larger the formation constants of solvato-complexes for 2-propanol and 2-methyl-2-propanol lead to lower reaction rates in the solution. The mechanism of the exchange reaction was also studied.
The substoichiometric method is applied to simple radiometric analysis. Two methods-the standard reagent method and the standard
sample method-are proposed. The validity of the principle of the methods is verified experimentally in the determination of
silver by the precipitation method, or of zinc by the ion-exchange or solvent-extraction method. The proposed methods are
simple and rapid compared with the conventional superstoichiometric method.
The activation of indium by gamma-ray source through absorption of photons of resonance energy and the threshold energy (appearance
energy) determination in indium compounds as well as some results of hot atom chemistry studies of indium compounds and of
implantation with indium ions are described.
Authors:H. Shoji, Y. Maruyama, K. Ogawa, Y. Oki, and N. Ikeda
A series of metal -diketonates were irradiated with bremsstrahlung of maximum energy of 50 MeV and the recoil behavior of7Be, formed from12C of ligands through12C(, n)7Be reaction, was investigated.7Be nuclides thus formed were detected partially as central metal atoms of the complexes. Complex yields of7Be were compared and an anomalously high yield was observed in tris-acetylacetonatocobalt(III) [Co(acac)3].
Authors:M. Nogami, T. Ishihara, K. Suzuki, and Y. Ikeda
Resins with monoamides as functional groups have been synthesized and their fundamental adsorption behaviors have been examined
for selective recovery of uranium(VI) from nitric acid media. The resins synthesized with porous silica support showed greatly
different adsorptions for U(VI) depending on the chemical structures of the functional group. Some resins show little or no
adsorption for U(VI) from 0.1 to 6 mol/dm3 HNO3. While, resins consisting of dimethylacrylamide (DMAA) showed an increasing adsorption with an increasing concentration of
HNO3 up to 9 to 12 mol/dm3. Other ions were not found to be adsorbed onto Silica-DMAA under similar solution conditions, which means that the resin
is selective for U(VI) in HNO3 media.
Authors:T. Suzuki, K. Otake, M. Sato, A. Ikeda, M. Aida, Y. Fujii, M. Hara, T. Mitsugashira, and M. Ozawa
The separation of Am and Cm by using the tertiary pyridine resin embedded in silica beads was studied in nitric acid/methanol
mixed solvent system. This separation system of Am and Cm is very simple and easy. The adsorption and separation behaviors
of Am and Cm were investigated with changing the nitric acid and the methanol concentrations. It was confirmed that Am can
be almost completely separated from Cm.
Authors:Chang-Kyu Kim, A. Takaku, M. Yamamoto, H. Kawamura, K. Shiraishi, Y. Igarashi, S. Igarashi, H. Takayama, and N. Ikeda
A new analytical technique using ICP-MS was applied to the determination of237Np in some environmental samples. The accuracy and precision of the new method were assessed by comparison with those of conventional NAA and -spectrometric method as well as by analysis of the intercomparison sample of Ravenglass NRPB silt. The results obtained by ICP-MS were in good agreement with those by NAA or -spectrometry at a relative deviation of 2–9%. The detection limit is 0.02 mBq/ml (26 mBq=1 ng).