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Yamada, Takashi*; Asai, Masato; Yonezawa, Chushiro*; Kakita, Kazutoshi*; Hirai, Shoji*
Radioisotopes, 69(9), p.287 - 297, 2020/09
We have confirmed that the commercially available Japanese "standard" gamma-ray analysis programs do not consider the effect of sample volume in calculating true coincidence summing (TCS) corrections, which results in underestimation of Cs radioactivity in cylindrical volume samples. In this work, we have developed and examined a practical TCS correction method for general Ge detectors which consider the effect of sample volume properly, and have confirmed that this method can reduce the
Cs radioactivity underestimation to less than 1%.
Saegusa, Jun; Yoda, Tomoyuki; Maeda, Satoshi; Okazaki, Tsutomu; Otani, Shuichi; Yamaguchi, Toshio; Kurita, Yoshiyuki; Hasumi, Atsushi; Yonezawa, Chushiro*; Takeishi, Minoru
Proceedings of 14th International Congress of the International Radiation Protection Association (IRPA-14), Vol.3 (Internet), p.1078 - 1085, 2017/11
After the nuclear accident at the Fukushima Daiichi Nuclear Power Plant in March 2011, the Japan Atomic Energy Agency has newly set up a laboratory for radioactivity analysis in Fukushima. At the laboratory, radioactivity concentrations of environmental samples such as soil, water, dust filter, plant, etc., approximately 1,000 samples in a month, are measured with high-resolution -ray spectrometry systems. The systems employ n-type HPGe detectors from Ortec. Since September 2012, characterization and upgrade of the systems have been performed aimed at enhancing reliability of analysis and convenience of customers. Resolving both systematic and technical issues, the laboratory has been accredited the ISO/IEC 17025 standard as a testing laboratory for radioactivity analysis.
Yonezawa, Chushiro*; Shirono, Katsuhiro*; Haraga, Tomoko
Bunseki Kagaku, 66(1), p.27 - 37, 2017/01
Times Cited Count:0 Percentile:0.00(Chemistry, Analytical)no abstracts in English
Yonezawa, Chushiro*; Yamamoto, Yoichi
Bunseki, (440), p.451 - 458, 2011/08
A worldwide radionuclide monitoring network for nuclear tests has detected the anthropogenic radioactive materials released in the atmosphere due to the accident of the Fukushima Daiichi Nuclear Power Plant impacted by the Great East Japan Earthquake on March 11, 2011. After four months have passed since the accident occurred, most overseas stations do not detect the radionuclides of Fukushima origin any more. The Takasaki station in Japan, however, is still detecting them every day. This paper describes radionuclide monitoring stations and the network of them as part of the International Monitoring System (IMS) in the Comprehensive Nuclear Test Ban Treaty (CTBT), as well as the measurement results of radionuclide particulates and radioactive isotopes of xenon released from the Fukushima Daiichi Nuclear Power Plant with the monitoring network.
Haraga, Tomoko; Kameo, Yutaka; Hoshi, Akiko; Yonezawa, Chushiro*; Nakashima, Mikio
JAERI-Tech 2005-050, 35 Pages, 2005/09
Non-destructive -ray spectrometry has been examined as a simple and rapid radioactivity measurement technique for the solidified products prepared by plasma melting for low level radioactive miscellaneous wastes generated from nuclear facilities. The Compton background resulting from the coexisting radionuclides pose a problem in the usual
-ray spectrometry which uses only a Ge detector. In order to reduce the background count and to measure the interested nuclide selectively, the coincidence and the anti-coincidence
-ray spectrometry using the Ge-BGO detector system were examined. As a result of applying the anti-coincidence
-ray spectrometry to a single
-ray emitter
Cs and the coincidence
-ray spectrometry to multiple
-ray emitter
Eu under existence of
Co, the detection limits of
Cs and
Eu in the sample, which contained
Co, were reduced by a factor of about 6 and 1.5, respectively. It was confirmed that the present methods are useful for the
-activity measurement of solidified products.
Matsue, Hideaki; Yonezawa, Chushiro
Bunseki Kagaku, 53(7), p.749 - 751, 2004/07
Times Cited Count:0 Percentile:0.00(Chemistry, Analytical)Multi-element determination in reference materials of soils (JASC401, JASC411) and sediments (NMIJ CRM 7302-a, NMIJ CRM 7303-a), which were prepared at the Japan Society for Analytical Chemistry and the National Institute of Advanced Industrial Science and Technology of the National Metrology Institute of Japan, respectively, has been carried out by neutron-induced prompt -ray analysis (PGA) using standard addition and
-standardization methods. Firstly, absolute Ti concentrations in the samples were determined accurately by the standard addition method. Secondly, relative multi-element concentrations were determined by the
-standardization method. Finally, absolute multi-element concentrations were obtained by normalizing the relative multi-element concentrations with the absolute Ti concentration in the samples. The 15 elements such as H, B, Na, Si, S, Cl, K, Ca, Ti Cr, Mn, Fe, Cd, Sm and Gd were determined by the
-PGA. Analytical results of these reference materials agreed with the certified or reference values within about 10%.
Matsue, Hideaki; Yonezawa, Chushiro
Journal of Radioanalytical and Nuclear Chemistry, 262(1), p.49 - 55, 2004/07
Times Cited Count:9 Percentile:51.87(Chemistry, Analytical)The recommended k factors for 81
-lines of 24 elements, which are useful for neutron induced prompt
-ray analysis (PGA) and are not influenced by neutron spectrum difference, were obtained from the k
factors measured with the cold and thermal guided neutron beams of JRR-3M by statistical calculation. The prompt
-ray emission probabilities were derived from the recommended k
-factors using atomic weight, isotopic abundance and thermal neutron cross-section of other nuclear constants consisting the k
factors, for which one can obtain accurate data. The derived
-ray emission probabilities for the light elements (H to Ca) well agreed within
10% with those of the ENSDF, which reflect recent data, which the agreements for heavy elements (Ti to Pb) were
40% with those of the ENSDF, which are still composed of old data.
Yonezawa, Chushiro; Matsue, Hideaki
Bunseki, 2004(2), p.75 - 82, 2004/02
no abstracts in English
Matsue, Hideaki; Yonezawa, Chushiro
Journal of Radioanalytical and Nuclear Chemistry, 257(3), p.565 - 571, 2003/09
Times Cited Count:7 Percentile:45.30(Chemistry, Analytical)no abstracts in English
Yonezawa, Chushiro; Matsue, Hideaki; Yukawa, M.*
Journal of Radioanalytical and Nuclear Chemistry, 255(1), p.105 - 109, 2003/01
Times Cited Count:5 Percentile:36.38(Chemistry, Analytical)no abstracts in English
Matsue, Hideaki; Yonezawa, Chushiro
Journal of Radioanalytical and Nuclear Chemistry, 255(1), p.125 - 129, 2003/01
Times Cited Count:8 Percentile:49.25(Chemistry, Analytical)no abstracts in English
Yonezawa, Chushiro; Matsue, Hideaki; Miyamoto, Yutaka; Suzuki, Daisuke; Yasuda, Kenichiro; Inagawa, Jun; Saito, Yoko
Jitsuyo Gamma-sen Sokutei Handobukku, 366 Pages, 2002/06
no abstracts in English
Yonezawa, Chushiro
Bunseki Kagaku, 51(2), p.61 - 96, 2002/02
Times Cited Count:5 Percentile:4.25(Chemistry, Analytical)no abstracts in English
Matsue, Hideaki; Yonezawa, Chushiro
Journal of Radioanalytical and Nuclear Chemistry, 249(1), p.11 - 14, 2001/06
no abstracts in English
Yonezawa, Chushiro
Non-Destructive Elemental Analysis, p.58 - 114, 2001/06
no abstracts in English
Kaneko, Junichi; Yonezawa, Chushiro; Kasugai, Yoshimi; Sumiya, Hitoshi*; Nishitani, Takeo
Diamond and Related Materials, 9(12), p.2019 - 2023, 2000/12
Times Cited Count:9 Percentile:47.30(Materials Science, Multidisciplinary)no abstracts in English
Raman, S.*; Yonezawa, Chushiro; Matsue, Hideaki; Iimura, Hideki; Shinohara, Nobuo
Nuclear Instruments and Methods in Physics Research A, 454(2-3), p.389 - 402, 2000/11
Times Cited Count:43 Percentile:91.03(Instruments & Instrumentation)no abstracts in English
Yonezawa, Chushiro; Matsue, Hideaki
Journal of Radioanalytical and Nuclear Chemistry, 244(2), p.373 - 378, 2000/05
Times Cited Count:12 Percentile:61.77(Chemistry, Analytical)no abstracts in English
Matsue, Hideaki; Yonezawa, Chushiro
Journal of Radioanalytical and Nuclear Chemistry, 245(1), p.189 - 194, 2000/04
Times Cited Count:21 Percentile:77.00(Chemistry, Analytical)no abstracts in English
Yonezawa, Chushiro
Isotope News, (544), p.30 - 31, 1999/08
no abstracts in English