Authors:S. Watanabe, N. Ishioka, T. Sekine, A. Osa, M. Koizumi, H. Shimomura, K. Yoshikawa, and H. Muramatsu
Ion implantation was applied to the production of endohedral 133Xe-fullerene. Using an isotope separator, 133Xe ions were implanted into a fullerene target of C60 and C70 produced by vacuum evaporation on a Ni backing. An HPLC analysis following dissolution of the fullerene targets in o-dichlorobenzene corroborated the formation of 133Xe@C60 and 133Xe@C70, showing a strong correlation between C60/C70 and 133Xe. The observed tailing following 133Xe peaks in the elution curves suggests a possibility of the isolation of endohedral 133Xe-fullerene from empty fullerene.
Authors:T. Katabuchi, S. Watanabe, N. Ishioka, Y. Iida, H. Hanaoka, K. Endo, and S. Matsuhashi
The radionuclide 67Cu was produced via the 68Zn(p,2p)67Cu reaction by irradiating enriched 68Zn targets with 70 MeV proton beam. Copper-67 was chemically separated from the zinc target by ion-exchange chromatography
using Chelex-100 chelating ion-exchange resin. Procedure for recovery of the enriched 68Zn was developed. The target recovery yield of this method was evaluated to be more than 97%.
Authors:G. Uchiyama, T. Asakura, S. Hotoku, H. Mineo, K. Kamei, M. Watanabe, and S. Fujine
The solvent extraction behavior of minor nuclides such as neptunium and technetium in a current PUREX process and an advanced PUREX process (PARC process) were studied by chemical flow sheet experiments using spent nuclear fuels. The uranium, plutonium, neptunium and technetium fractions distributed in the products and raffinates of the PARC process showed that n-butyraldehyde was an effective reductant of neptunium(VI) in the presence of uranium(VI) and plutonium(IV). It was also found that scrubbing with high acid concentration was effective for technetium separation.
Authors:T. Shinonaga, S. Ambe, S. Enomoto, H. Maeda, M. Iwamoto, T. Watanabe, and I. Yamaguchi
The direct absorption of atmospheric elements via soybean leaves has been studied using a radioactive multitra r technique. Soybean was cultivated until it bore seeds in a box under no-rain conditions and with introduction of multitracer-adsorbed cellulose powders. The radioactive nuclides of 40 elements were produced from Au target irradiated with14N, and the nuclides with relatively long half-life of the elements Sc, Mn, Co, As, Se, Rb, Sr, Y, Eu, Gd, Yb, Re, and Ir were dominantly observed in each part of soybean plant.
Authors:Y Kobayashi, M. Kubo, Y. Yamada, T. Saito, H. Ueno, H. Ogawa, W. Sato, K. Yoneda, H. Watanabe, N. Imai, H. Miyoshi, and K. Asahi
In-beam Mössbauer spectra of 57Fe, decayed from short-lived 57Mn (T1/2 = 1.45 min) implanted into potassium permanganate, KMnO4, were measured at temperatures between 11 K and 130 K. This is the first application of a secondary RI beam to the study of valence states after nuclear transformation. The in-beam Mössbauer spectra obtained below 90 K could be analyzed with two components, a doublet and a singlet. From the calculations of the molecular orbital wave functions, the singlet is suggested to be substitutional 57Fe atoms for Mn-sites in tetrahedral [MnO4]– with an unusually high valence state of Fe8+.
Authors:W. Sato, H. Ueno, H. Watanabe, H. Ogawa, H. Miyoshi, N. Imai, A. Yoshimi, K. Yoneda, D. Kameda, Y. Kobayashi, and K. Asahi
A new 19F probe disintegrated from short-lived 19O has been developed for the first time for time-differential perturbed angular correlation method. The angular correlation coefficient for the relevant cascade has been experimentally estimated to be A22 = -0.17±0.01. As the first application of this technique to condensed matter physics, the probe was implanted in polycrystalline fullerene C60. We have observed two contrastive perturbations acting on the probe nuclei, which reflect electrostatic and dynamic interactions with the extranuclear field.
Authors:Y. Kobayashi, Y. Tsuruoka, M. Kubo, H. Nonaka, Y. Yamada, Y. Sakai, H. Shoji, W. Sato, A. Shinohara, Y. Watanabe, and H. Matsue
In order to investigate the physical and chemical effects of neutron capture reaction, a neutron in-beam Mössbauer spectroscopic
study on two isomorphs of iron disulfide: pyrite and marcasite, were carried out with a parallel plate avalanche counter at
room temperature. In both compounds only two major products accounted for the obtained spectrum: one with Mössbauer parameters
close to the parent compound and the other one considered to be a new product. The yield of the parent-like species was different
in the two isomorphs.
Authors:K. Kobayashi, M. Kuwano, K. Sueki, K. Kikuchi, Y. Achiba, H. Nakahara, N. Kananishi, M. Watanabe, and K. Tomura
Advantages and uniqueness of radiochemical techniques in fullerene studies are pointed out. Some experimental data are presented on metallofullerenes production yields, HPLC elution behaviors of Y, La, Gd containing fullerenes, encapsulation of a new metal in the carbon cage, stability of the carbon cage against recoil energy, and the distribution of metallofullerenes among various organs of rats.
Authors:S. Watanabe, Y. Iida, N. Suzui, T. Katabuchi, S. Ishii, N. Kawachi, H. Hanaoka, S. Matsuhashi, K. Endo, and N. Ishioka
Copper-64 was produced by the 64Ni(p, n)64Cu reaction using enriched 64NiO target. We investigated and compared the production yield of 64Cu for proton beams of various energies by using a thick target. Enriched 64Ni was recovered with high yield by simple procedures. Imaging studies using positron emission tomography (PET) and positron
emitting tracer imaging system (PETIS) were performed. We obtained clear images in PET and PETIS studies. The results of this
study indicate that 64Cu can be utilized as a biomedical tracer for the molecular imaging both in animals and plants.