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Abstract  

The reactivity of recoil tritium in the T-for-H substitution was studied in mixtures of benzene, hexane, cyclohexane or cyclohexane-d12 with lithium carbonate which were irradiated in a reactor. The relative rates per C–H bond of hexane and cyclohexane to benzene were somewhat less than one third. The H/D isotope effect in cyclohexane was given as 1.14.

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Abstract  

We have analyzed 16 elements and the radioactivity of 210Pb in a wood disk, across the annual rings to find out a promising tool for dendrochronology (chronology of wood) both for a Japanese wood, Cryptomeria japonica, and for an Indonesian rain forest wood, Alstonia, which does not form annual rings because of the relatively constant climate of the rain forest. As a result, only Mg concentration showed similar, smooth decreasing tendency in both wood species. The smooth change of the Mg concentration across the annual rings along with the growth suggested the possibility of the Mg concentration determination as a promising dendrochronological tool.

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Abstract  

Reactions of recoil tritium with benzoic acid, acetanilide and -phenethyl alcohol were studied using the3He/n,p/3H reaction. The tritium distribution in the aromatic ring is approximately uniform in all the irradiated compounds and the tritium activity per C–H bond in the methyl and ethylene groups is 7 to 8 relative to that of the corresponding ring as standard /=100/. These findings are substantially the same as those obtained previously by the6Li/n,/3H reactions, suggesting the same mechanism of tritiation for both recoil reactions. The tritiated parent compounds were obtained in high radiochemical yields; 45% for benzoic acid, 30% for acetanilide, 12% for -phenethyl alcohol.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Nogawa, S. Momose, K. Miyazawa, Y. Makide, K. Oohashi, K. Hashimoto, and N. Morikawa

Abstract  

Optimum conditions were determined for high-yield synthesis of186Re- and188Re-meso-2, 3-dimercaptosuccinic acid complexes applicable to animal injection. The yield was more than 95% under the conditions used. The bone accumulation of the complexes was remarkable in the biodistributions in mice.

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Abstract  

The 63Ni in copper samples exposed by the Hiroshima atomic bomb was clearly measured for the first time by liquid scientillation method For the measurement, the chemical separation scheme previously developed was improved The obtained result was agreed with that estimated by the new dosimetry system for atomic bomb survivor studies, DS02.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Shibata, K. Takamiya, Y. Ota, N. Nogawa, Y. Ito, T. Shibata, M. Hoshi, S. Endo, H. Hasai, and S. Fujita
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