Neutron-capture γ-ray activation analysis was investigated using a 300 mCi Am−Be neutron source. Prominent photopeaks available
for the analysis were observed in several high-sensitivity elements, e.g. 0.477 MeV for boron, 0.336 MeV for samarium, 0.559
for cadmium, 0.230 MeV for cobalt, 0.370 MeV for mercury, and 0.518 MeV and 0.792 MeV for chlorine. As a practical application
of the method, determinations of the chlorine contents of various organic compounds were carried out, and it is shown that
Cl contents of 5–50 w/v% can be determined in this way with an experimental error of less than 5%.
Authors:Y. Kusaka, H. Tsuji, Y. Tamari, T. Sagawa, S. Ohmori, S. Imai, and T. Ozaki
A new radiochemical group separation method using APDC reagent in the extraction procedure has been developed. The method
has been applied to the radiochemical separation for activated biological samples and also to the preconcentration technique
for sea water samples. The transition elements are extracted into chloroform phase from the pH 3.0 aqueous phase and only
manganese is subsequently extracted from the pH 7.0 aqueous phase. The validity of the method is demonstrated by analyzing
the NBS standard reference materials. In the specimens preconcentrated from the sea water samples adjusted pH to 5.5, vanadium,
manganese, copper and zinc can be determined.
Authors:Y. Kusaka, H. Tsuji, Y. Fujimoto, K. Ishida, Y. Fukui, T. Mamuro, T. Matsunami, A. Mizohata, and S. Hirai
This report is the results of the studies on NAA of groundwater samples with comparison between direct and evaporation methods,
and of the applications for the samples of alluvium plain composed with granitiform soils and of Neogene strata composed with
Authors:T. Fujinaga, Y. Kusaka, M. Koyama, H. Tsuji, T. Mitsuji, S. Imai, J. Okuda, T. Takamatsu, and T. Ozaki
A method is described for the determination of trace metal ions, V, Al, Cu, Mo Zn, and U, in natural water samples by neutron
activation analysis, using organic coprecipitation as a preconcentration method. The preconcentration of trace elements was
accomplished by converting the dissolved trace metal ions into the oxine chelates atpH 5.2 and extraction of the chelates witho-phenylphenol which is a liquid above 56 °C and solidifies at room temperature. After cooling the extraction system, the fine
particles of the organic phase were collected on a millipore filter and the precipitate was air-dried in a clean environment.
The solid extract was wrapped up in a sheet of clean polyethylene and subjected to neutron irradiation in a reactor for less
than 10 min at a thermal flux of 2·1013 n·cm−2·sec−1. γ-Ray spectrometry by a coaxial Ge(Li) detector connected to a 1024-channel PHA was performed on the irradiated sample without
further chemical separation, and thus the ppb level concentration of the elements in natural water samples could be determined.
The fundamental study of the collection of the trace elements is also described.
Authors:S. Ohmori, H. Tsuji, Y. Kusaka, T. Takeuchi, T. Hayashi, J. Takada, M. Koyama, H. Kozuka, M. Shinogi, A. Aoki, K. Katayama, and T. Tomiyama
With the aim of indicating environmental pollution effects by heavy metals on humans using hair, nondestructive activation
analysis was applied to 382 normal Japanese hair samples (background level). Elemental contents of hair could be determined
for Ag, Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, I, K, La, Mg, Mn, Na, S, Sb, Sc, Se, Sm, Ti, V and Zn. As these elements
in hair have wide concentration ranges, the differences in concentrations distribution between groups (sex, age, permanent
treatment and regional difference) are discussed. A method for hair sampling is presented.