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Ra in natural water samples by ICP-MSTomita, Jumpei; Ozawa, Mayumi; Ohara, Yoshiyuki; Miyamoto, Yutaka
KEK Proceedings 2021-2, p.130 - 134, 2021/12
no abstracts in English
Tomita, Ryohei; Tomita, Jumpei; Yomogida, Takumi; Suzuki, Daisuke; Yasuda, Kenichiro; Esaka, Fumitaka; Miyamoto, Yutaka
KEK Proceedings 2021-2, p.146 - 150, 2021/12
no abstracts in English
Suzuki, Daisuke; Tomita, Ryohei; Tomita, Jumpei; Esaka, Fumitaka; Yasuda, Kenichiro; Miyamoto, Yutaka
Journal of Radioanalytical and Nuclear Chemistry, 328(1), p.103 - 111, 2021/04
Times Cited Count：0 Percentile：0.01(Chemistry, Analytical)An analytical technique was developed to determine the age of uranium particles for safeguards. After the chemical separation of uranium and thorium, the 
Th/
U ratio was measured using single-collector inductively coupled plasma mass spectrometry and a 
U-based reference material comprising a certain amount of 
Th as a progeny nuclide of U. The results allowed us to determine the purification age of two certified materials, i.e., U-850 and U-100, which was in good agreement with the reference purification age (61 y). Moreover, the age of a single U-850 particle was determined with a difference of -28 to 2 years from the reference date.
Tomita, Jumpei
Zusetsu Nihon No Onsen No, 170 Onsen No Saiensu, P. 111, 2020/03
no abstracts in English
Sr in urine sample; Rapid separation of Sr by phosphate co-precipitation and extraction chromatography, followed by determination by triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS)Tomita, Jumpei; Takeuchi, Erina
Applied Radiation and Isotopes, 150, p.103 - 109, 2019/08
Times Cited Count：6 Percentile：68.11(Chemistry, Inorganic & Nuclear)A rapid analytical method for determining Sr in urine samples (1-2 L) was developed to assess the internal exposure of workers in a radiological emergency. Strontium in a urine sample was rapidly separated by phosphate co-precipitation, followed by extraction chromatography with a tandem column of Pre-filter, TRU and Sr resin, and the Sr activity was determined by ICP-MS/MS. Measurement in the MS/MS mode with an O
reaction gas flow rate 1 mL min
showed no tailing of 
Sr at m/z = 90 up to 50 mg-Sr L. The interferences of Ge, Se and Zr at m/z = 90 were successfully removed by chemical separation. This analytical method was validated by the results of the analyses of synthetic urine samples (1.2-1.6 L) containing a known amount of Sr along with 1 mg of each of Ge, Se, Sr and Zr. The turnaround time for analysis was about 10 h, and the detection limit of Sr was approximately 1 Bq per urine sample.
Tomita, Jumpei
Bunseki, 2019(3), p.112 - 113, 2019/03
no abstracts in English
-ray spectrometry; Application of 
pre-concentration from large volume of water sample using Powdex resin and barium sulfate coprecipitation of radium isotopesTomita, Jumpei; Abe, Takuya
JAEA-Research 2016-026, 12 Pages, 2017/03
JAEA-Research-2016-026.pdf:1.15MB
An analytical method of low-level Ra isotopes in freshwater samples with combination of pre-concentration from large volume of water sample (
170 L) using Powdex resin and -ray spectrometry followed by simple coprecipitation of Ra was developed. 
pre-concentration of Ra by batch method using Powder resin was examined, and it was shown that the amount of the resin required collecting Ra in the water sample could be determined by measuring the electric conductivity (EC) of water sample. It was found that coprecipitation of Ra with barium sulfate could remove more than 96% of potassium that increases the background. The validation of this method was confirmed by the analyses of 170 L of water sample containing the known amount of Ra isotopes with different EC. Among the analyses, the recovery of Ra was 98% in average and detection limits of Ra and 
Ra were achieved to be approximately 0.3 and 0.5 mBq L, respectively.
-ray spectra measured inside and outside a house in FukushimaTanimura, Yoshihiko; Tomita, Jumpei; Yoshitomi, Hiroshi; Yoshizawa, Michio; Hakozaki, Ryozo*; Takahashi, Sohei*
Hoken Butsuri, 51(3), p.141 - 146, 2016/09
Photon spectra were measured inside and outside a house in Minami-Soma city by using a NaI(Tl) scintillation spectrometer. The photons were categorized into three groups according to their energy. The groups were (1) scattered photons, which include low energy photons, (2) direct photons from 
Cs and 
Cs sources and (3) the other photons. Then the ratios of the ambient dose equivalents H
(10) of the scattered photons to those of the direct photons from the Cs and Cs sources have been evaluated from the measured photon spectra. The ratios are high inside the house compared with those out of the house. It was found that the scattered photons contribute to the H(10) by more than 50
inside the house. The ambient dose equivalent average energies of the scattered photons are around 0.25 MeV both inside and outside the house. These data is worthwhile to design the optimum shielding for the protection against the public radiation exposure.
pre-concentration of Sr from large volume of freshwater sample using Powdex resinTomita, Jumpei; Yamamoto, Masayoshi*; Nozaki, Teo; Tanimura, Yoshihiko*; Oishi, Tetsuya
Journal of Environmental Radioactivity, 146, p.88 - 93, 2015/08
Times Cited Count：10 Percentile：38.89(Environmental Sciences)Yamamoto, Masayoshi*; Tomita, Jumpei
Onsen Kagaku, 64(4), p.388 - 401, 2015/03
no abstracts in English
Endo, Satoru*; Tomita, Jumpei*; Tanaka, Kenichi*; Yamamoto, Masayoshi*; Fukutani, Satoshi*; Imanaka, Tetsuji*; Sakaguchi, Aya*; Amano, Hikaru; Kawamura, Hidehisa*; Kawamura, Hisao*; et al.
Radiation and Environmental Biophysics, 47(3), p.359 - 365, 2008/07
Times Cited Count：5 Percentile：23.04(Biology)Dolon village located about 60 km from the border of the Semipalatinsk Nuclear Test Site is known to be heavily contaminated by the first USSR atomic bomb test in August 1949. Soil samples around Dolon were taken in October 2005 in an attempt to evaluate internal thyroid dose arising from incorporation of radioiodine isotopes (mainly 
I). Iodine-129 in soil was measured by using the technique of Accelerator Mass Spectrometry. From the relationship between 
I and Cs (corrected for background and decay from 1949 to 2005) accumulated levels, the background level of I and the I/Cs ratio around Dolon were estimated to be (6.4 
0.4) 
10
atoms m
and 0.25 0.16, respectively. This I/Cs ratio is almost similar to the fission yield ratio for 
Pu fast fission (0.24).
Sr in large water samplesTomita, Jumpei; Nozaki, Teo; Tanimura, Yoshihiko; Yoshizawa, Michio
no journal, ,
Preconcentration method of Sr with Powdex resin (PCH for cation) at the field was examined to develop the analytical method for Sr in large water samples, which enables the analysis for a number of samples. In the experiment with 250 L of tap water samples, nearly 100% of Sr in water was adsorbed at 1 g L of PCH/water ratio, and duplication of boiling with 3M HNO
at 0.2 g mL of PCH/3M HNO allowed the elution of 80% of Sr adsorbed.
-ray spectra in living environment around Fukushima Daiichi Nuclear Power PlantTanimura, Yoshihiko; Tomita, Jumpei; Yoshitomi, Hiroshi; Yoshizawa, Michio; Hakozaki, Ryozo*; Takahashi, Sohei*
no journal, ,
A easy-to-use -ray spectrometry technique have been developed using a hand-held NaI(Tl) spectrometer and the MAXED unfolding code. The -ray spectra in the living environment were measured inside and outside the house at the Minami-Soma city in the Fukushima prefecture. It was found that the dose contribution of the low energy photons is large inside the house compared with those measured outside the house.
Tomita, Jumpei; Nozaki, Teo; Oishi, Tetsuya; Sasa, Yoichi
no journal, ,
no abstracts in English
Tomita, Jumpei
no journal, ,
no abstracts in English
Tomita, Jumpei; Abe, Takuya; Sakaguchi, Aya*; Miyata, Yoshiki*; Nagao, Seiya*; Yamamoto, Masayoshi*
no journal, ,
no abstracts in English
Tomita, Jumpei; Miyata, Yoshiki*; Hama, Katsuhiro; Sakaguchi, Aya*; Nagao, Seiya*; Yamamoto, Masayoshi*
no journal, ,
no abstracts in English
Sr in urine samples by extraction chromatography coupled to ICP-MS/MSTomita, Jumpei; Takeuchi, Erina
no journal, ,
no abstracts in English
Takeuchi, Erina; Tomita, Jumpei; Ohara, Yoshiyuki
no journal, ,
no abstracts in English
