Authors:Y. Toh, M. Oshima, M. Koizumi, A. Kimura, and Y. Hatsukawa
In order to improve the limits of quantification for trace elements, we applied the multiple gamma-ray detection method in
the prompt gamma-ray analysis (PGA). The Clover Ge detector system was constructed for multiple prompt gamma-ray analysis
(MPGA) at the neutron guide hall of the JRR-3M reactor of the Japan Atomic Energy Agency (JAEA). The MPGA system consists
of three Clover detectors and a BGO Compton suppressor. The instrumentation of the MPGA beam line and the detector system
were developed. The estimated limit of quantification of cadmium in the plastic sample is approximately 0.1 ppm. The capability
of the MPGA system could be improved by modification of the detector system, shield arrangement, software algorithm, etc.
Authors:Y. Toh, M. Oshima, Y. Hatsukawa, T. Hayakawa, and N. Shinohara
A comparison method, utilizing neutron activation analysis followed by multidimensional spectrum analysis was proven to provide accurate quantification of the multi-element samples. In this study, 23 elements were detected simultaneously in a sample containing standard elements for neutron activation analysis. The method presented here can be applied for about 50 elements.
Authors:A. Kimura, Y. Toh, M. Oshima, and Y. Hatsukawa
Recycling steel products demands a new technique for determining tramp elements in steel. Tramp elements, As and Sb, in some
iron certified reference materials were determined by neutron activation analysis with multiple gamma-ray detection method
and reported in MTAA11. In MTAA12, the authors reported the lower limit of determination values (LDL) and the dispersion of
this method. The values of the LDLs for As and Sb in high purity iron were 0.002 and 0.0009 μg·g−1. The dispersion is small enough to satisfy the demand from materials science.
Authors:Y. Hatsukawa, M. Oshima, T. Hayakawa, Y. Toh, and N. Shinohara
Feasibility of the method of multidimensional -ray spectrometer for neutron activation analysis was examined. Reference igneous rock (JP-1, JB-1a and JB-1) samples issued by the Geological Survey of Japan (GSJ) and the Allende meteorite reference sample were irradiated in a research reactor, and multiple -rays from the produced radioisotopes via neutron capture reactions were measured using an array of twelve germanium detectors with BGO Compton suppressors called GEMINI. Simultaneously thirty elements were observed with no chemical separation. The observed smallest component was Eu contained in JP-1 with abundance of 4 ppb.
Authors:A. Kimura, Y. Toh, M. Oshima, Y. Hatsukawa, and J. Goto
Recycled steel products demands a new technique for determining tramp elements in steel. In this paper, As and Sb in iron
certified reference materials were determined by neutron activation analysis with the multiple gamma-ray detection method.
The determined values are in good agreement with certified and reference values. The lower determination limits (LDL) for
As and Sb in high purity iron are 0.012 and 0.0025 ppm, respectively. As the demanded LDL for As and Sb is 0.1 ppm, the method
described in this work is suitable for determining As and Sb in recycled steel.
Authors:S. Usuda, H. Yoshikawa, M. Magara, and Y. Hatsukawa
Adsorption behaviour of Bk/III/ on anion-exchange resin in mineral acid-methyl alcohol mixtures has been investigated. Berkelium was successively separated with a HCl–CH3OH mixture at elevated temperatures within 5 min from an Al catcher foil collecting the recoil products of the4He+241Am reaction. The counting source of Bk was immediately prepared for alpha- and X-ray spectrum measurements. Rapid separation of Bk from Ce was also performed by the use of a HNO3–CH3OH mixture.
Authors:E. Furuta, H. Nakahara, Y. Hatsukawa, H. Matsue, and H. Sakane
In Japan, cosmetics claiming hormesis effect are available through Internet. Although these cosmetics show the contents, they
never mention the minor elements and radioactive sources. The existence of radioisotopes, however, was observed by measurements
of the gamma-rays with a HPGe detector. In this study, in order to clarify the contents of trace elements, the hormesis cosmetics
including radioactive sources were analyzed using INAA, PGAA and NAA with multiple gamma-ray detection (NAAMG). Nineteen elements
were analyzed quantitatively in hormesis cosmetics by INAA, PGAA and NAAMG and 16 elements were detected qualitatively by
Authors:Y. Hatsukawa, Y. Miyamoto, Y. Toh, M. Oshima, M. Hosein Mahmudy Gharaie, K. Goto, and K. Toyoda
In this study, using neutron activation analysis with multi-parameter coincidence method which was developed at Japan Atomic
Energy Agency (JAEA), a non-destructive, ultra-high sensitive multi-elemental determination has been realized. The multi-parameter
coincidence method is carried out with an array of 19 germanium detectors, GEMINI-II. Using this system, very weak γ-rays
emitted from trace amounts of elements can be detected. The iridium concentration has been determined by means of neutron
activation analysis with multi-parameter coincidence method for Cuban sediment samples across the K/T boundary strata.
Authors:Y. Hatsukawa, Y. Miyamoto, T. Hayakawa, Y. Toh, A. Kimura, and M. Oshima
Neutron activation analysis with multi-parameter coincidence method was developed at the Japan Atomic Energy Agency (JAEA)
and a non-destructive, ultra-high sensitive multi-elemental determination has been realized. The multi-parameter coincidence
method is carried out with an array of 19 germanium detectors, GEMINI-II. Using this system, very weak γ-rays emitted from
trace amounts of elements can be detected. The presolar grains were extracted from the Allende meteorite. Trace elements in
the presolar diamonds were measured by neutron activation analysis with multi-parameter coincidence method.
Authors:Y. Hatsukawa, Y. Toh, M. Oshima, A. Kimura, and M. Hosein Mahmudy Gharaie
In this study, sensitive trace element analyses were carried out without chemical separation by the combination of neutron
activation analysis and multi-parameter coincidence spectroscopy. A long-lived radioisotope 129I in algae samples and iridium in geological samples were analyzed.