Annual report on the environmental radiation monitoring around the Tokai Reprocessing Plant FY2023

Kokubun, Yuji; Hosomi, Kenji; Nagaoka, Mika; Seya, Natsumi; Inoue, Kazumi; Koike, Yuko; Uchiyama, Rei; Sasaki, Kazuki; Maehara, Yushi; Matsuo, Kazuki; et al.

JAEA-Review 2024-054, 168 Pages, 2025/03

JAEA-Review-2024-054.pdf:2.73MB

The Nuclear Fuel Cycle Engineering Laboratories conducts environmental radiation monitoring around the reprocessing plant in accordance with the "Safety Regulations for Reprocessing Plant of JAEA, Part IV: Environmental Monitoring". This report summarizes the results of environmental radiation monitoring conducted during the period from April 2023 to March 2024 and the results of dose calculations for the surrounding public due to the release of radioactive materials from the plant into the atmosphere and ocean. In the results of the above environmental radiation monitoring, several items were affected by radioactive materials emitted from the accident at the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company, Incorporated (changed to Tokyo Electric Power Holdings, Inc. on April 1, 2016), which occurred in March 2011. In addition, environmental monitoring plan, analysis and measurement methods, monitoring data and their chronological change, meteorological data after statistical processing, status of radioactive waste release and evaluation results of the data over the normal range are included as appendices.

Dissolution behavior of calcium uranate under oxidizing and reducing conditions

Kato, Yuto*; Sasaki, Takayuki*; Tonna, Ryutaro*; Kobayashi, Taishi*; Okamoto, Yoshihiro

Applied Geochemistry, 175, p.106196_1 - 106196_9, 2024/11

https://doi.org/10.1016/j.apgeochem.2024.106196

Dissolution behavior and aging of iron-uranium oxide

Tonna, Ryutaro*; Sasaki, Takayuki*; Okamoto, Yoshihiro; Kobayashi, Taishi*; Akiyama, Daisuke*; Kirishima, Akira*; Sato, Nobuaki*

Journal of Nuclear Materials, 589, p.154862_1 - 154862_10, 2024/02

https://doi.org/10.1016/j.jnucmat.2023.154862

The dissolution behavior of FeUO compounds formed by a high-temperature reaction of UO with iron, a stainless-steel component of reactor structural materials, was investigated under atmospheric conditions. The compounds were prepared in an electric furnace using UO and FeO as starting materials, and their solid states were analyzed using X-ray diffraction, scanning electron microscopy energy dispersive X-ray spectroscopy, and X-ray absorption fine structure spectroscopy. The concentration of nuclides dissolved in water was examined by performing static leaching tests of FeUO compounds for up to three months. A redox reaction was proposed to occur between trivalent Fe and pentavalent U ions in the early stage of FeUO dissolution. It was thermodynamically deduced that the reduced divalent Fe ion was finally oxidized into a trivalent ion in the presence of dissolved oxygen, and iron hydroxide limited the solubility of Fe. Meanwhile, the concentration of hexavalent U (i.e., uranyl ion) was limited owing to the presence of secondary minerals such as metaschoepite and sodium uranate and subsequently decreased, possibly owing to sorption on Fe oxides, for example. The concentrations of multivalent ions of fission products, such as Ru and Ce, also decreased, likely for the reason above. By contrast, the concentration of soluble Cs ions did not decrease. The validity of this interpretation was supported by comparing the results with the dissolution behavior of a reference sample (Fe-free UO).

In situ neutron imaging of lithium-ion batteries during heating to thermal runaway

Nozaki, Hiroshi*; Kondo, Hiroki*; Shinohara, Takenao; Setoyama, Daigo*; Matsumoto, Yoshihiro*; Sasaki, Tsuyoshi*; Isegawa, Kazuhisa*; Hayashida, Hirotoshi*

Scientific Reports (Internet), 13, p.22082_1 - 22082_8, 2023/12

https://doi.org/10.1038/s41598-023-49399-1

Magnetically navigated protein transduction in vivo using iron oxide-nanogel chaperone hybrid

Kawasaki, Riku*; Sasaki, Yoshihiro*; Nishimura, Tomoki*; Katagiri, Kiyofumi*; Morita, Keiichi*; Sekine, Yurina; Sawada, Shinichi*; Mukai, Sadaatsu*; Akiyoshi, Kazunari*

Advanced Healthcare Materials, 10(9), p.2001988_1 - 2001988_8, 2021/05

https://doi.org/10.1002/adhm.202001988

Systems for "protein transduction", the intracellular delivery of functional proteins, are needed to address the deliverability challenges of protein therapy, but protein transfer in vivo remains difficult. In this study, we have developed a magnetically induced in vivo protein transfection system using a magnetic nanogel chaperone (MC) composed of iron oxide nanoparticles and polysaccharide nanogels. Experiments using an oral cancer model have shown that this MC system is useful for cancer treatment.

Treatment of electric hydraulic control fluid (EHC Oil) with steam-reforming system

Okadome, Yoshihiro; Aoyama, Yoshio; Sasaki, Yu; Fukushima, Mineo

Proceedings of 2017 International Congress on Advances in Nuclear Power Plants (ICAPP 2017) (CD-ROM), 6 Pages, 2017/04

The Effects of ion beam irradiation on variation in the M generation of two strains of var.

Honda, Kazushige*; Taneichi, Shuhei*; Maeda, Tomoo*; Goto, Satoshi*; Shikanai, Yasuhiro*; Sasaki, Kazuya*; Nozawa, Shigeki; Hase, Yoshihiro

JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 107, 2016/02

https://doi.org/10.11484/jaea-review-2015-022

no abstracts in English

"Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds" summary of the researches for three years (Contract research)

Sasaki, Yuji; Tsubata, Yasuhiro; Kitatsuji, Yoshihiro; Sugo, Yumi; Shirasu, Noriko; Ikeda, Yasuhisa*; Kawasaki, Takeshi*; Suzuki, Tomoya*; Mimura, Hitoshi*; Usuda, Shigekazu*; et al.

JAEA-Research 2014-008, 220 Pages, 2014/06

JAEA-Research-2014-008.pdf:41.81MB

The researches on Development of mutual separation technology of minor actinides by the novel hydrophilic and lipophilic diamide compounds, entrusted to Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan, from 2010 to 2012 are summarized. This project was composed of three themes, those are (1) Development of total recovery of MA+Ln: basic researches for new extractant, DOODA, (2) Development of mutual separation of Am/Cm/Ln: basic researches of Ln-complex, solvent extraction, and extraction chromatography, and (3) Evaluation of separation technique: process simulation. For topic (1), we summarized the information on characteristic of DOODA extractant. For topic (2), we summarized the information on structures of Ln-complexes, solvent extraction and chromatography. For topic (3), we summarized the information on conditions of mixer-settler and evaluation of each fraction separated.

Mutual separation of Am/Cm/Ln by the use of novel-triamide, NTAamide and water-soluble diglycolamide

Sasaki, Yuji; Tsubata, Yasuhiro; Kitatsuji, Yoshihiro; Sugo, Yumi; Shirasu, Noriko; Morita, Yasuji

Proceedings of International Nuclear Fuel Cycle Conference; Nuclear Energy at a Crossroads (GLOBAL 2013) (CD-ROM), p.1079 - 1082, 2013/09

Mutual separation of Am, Cm and lanthanides (Ln) is important to develop the partitioning process of high-level radioactive liquid waste, because the application to their different disposal methods are advantageous. Namely, Am is studied for transmutation due to the reduction of long half-life radionuclides, Cm should be kept in interim storage in order to reduce the calorific value, and Ln should be present in the vitrified radioactive waste toward the geological disposal. However, this mutual separation method is difficult to establish because they have very similar chemical behavior, same oxidation state (III) and similar ionic radii. The development of their mutual separation is termed as the challenging study. In order to obtain the satisfactory results, the property of extractant requires the differentiation of actinide (An) from Ln, high preferability to different ionic radii between Am and Cm, and high extractability to hard acids. Therefore, the extractant have to include both N atom, whose soft donor has high selectivity between An and Ln, and O atoms for the strong extractability to An. The new extractant, NTAamide (N,N,N',N',N'',N''-hexaoctyl-nitrirotriacetamide) is a triamide having N donor at the center of backbone, then NTAamide has hybrid performance of complexation to metals by soft N and three hard amidic O atoms. It is clear that NTAamide can extract trivalent An at diluted HNO with small D(Ln), the separation of An from Ln can be carried out at that condition. The SF of Am/Cm by NTAamide is approximate 1.8, which is not so high to separate each other. The combination of NTAamide of extractant and TEDGA (N,N,N',N'-tetraethyl-diglycolamide) as a masking agent in the aqueous phase shows very high SF(Am/Cm) of maximal 6.5. It is obvious that NTAamide is a promising extractant to achieve the mutual separation among Am/Cm/Ln.

Crossbreeding of a metallic color carnation and diversification of the peculiar coloration by ion-beam irradiation

Okamura, Masachika*; Nakayama, Masayoshi*; Umemoto, Naoyuki*; Cano, E. A.*; Hase, Yoshihiro; Nishizaki, Yuzo*; Sasaki, Nobuhiro*; Ozeki, Yoshihiro*

Euphytica, 191(1), p.45 - 56, 2013/05

https://doi.org/10.1007/s10681-012-0859-x

A few carnation cultivars are known to display a peculiar dusky color supposedly caused by anthocyanic vacuolar inclusions (AVIs). The hereditary pattern suggests that the peculiar color is controlled by a single recessive factor tightly linked with existence of AVIs containing non-acylated anthocyanins. To diversify the peculiar color carnation, we produced a bluish purple line displaying a highly novel metallic appearance by crossbreeding. By subjecting the line to ion-beam irradiation, we generated metallic reddish purple, metallic crimson and metallic red lines. All four metallic lines did not have transcripts for anthocyanin malyltransferase. In contrast to the dusky color types, metallic lines have highly condensed AVIs and water-clear vacuolar sap in the petal adaxial epidermal cells. We demonstrated that (1) a factor generating the AVIs is inactivated anthocyanin malyltransferase gene, (2) AVIs in water-clear vacuolar sap in the adaxial epidermal cells generate the novel metallic appearance, and (3) ion beam breeding is a useful tool for increasing metallic colors by changing anthocyanin structure and the level of AVIs.