Sodium-cooled Fast Reactors

Ohshima, Hiroyuki; Morishita, Masaki*; Aizawa, Kosuke; Ando, Masanori; Ashida, Takashi; Chikazawa, Yoshitaka; Doda, Norihiro; Enuma, Yasuhiro; Ezure, Toshiki; Fukano, Yoshitaka; et al.

Sodium-cooled Fast Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.3, 631 Pages, 2022/07

https://shop.elsevier.com/books/sodium-cooled-fast-reactors/morishita/978-0-12-824076-2

This book is a collection of the past experience of design, construction, and operation of two reactors, the latest knowledge and technology for SFR designs, and the future prospects of SFR development in Japan. It is intended to provide the perspective and the relevant knowledge to enable readers to become more familiar with SFR technology.

Direct observation of lattice symmetry breaking at the hidden-order transition in URuSi

Tonegawa, Sho*; Kasahara, Shigeru*; Fukuda, Tatsuo; Sugimoto, Kunihisa*; Yasuda, Nobuhiro*; Tsuruhara, Yugo*; Watanabe, Daiki*; Mizukami, Yuta*; Haga, Yoshinori; Matsuda, Tatsuma*; et al.

Nature Communications (Internet), 5, p.4188_1 - 4188_7, 2014/06

https://doi.org/10.1038/ncomms5188

The Creep rupture strength evaluation in welded joint of Mod.9Cr-1Mo steel

Wakai, Takashi; Nagae, Yuji; Takaya, Shigeru; Obara, Satoshi; Date, Shingo*; Yamamoto, Kenji*; Kikuchi, Koichi*; Sato, Kenichiro*

Tainetsu Kinzoku Zairyo Dai-123-Iinkai Kenkyu Hokoku, 52(2), p.147 - 159, 2011/07

By employing high-Cr ferritic steels to the structural materials for JSFR, a compact plant designing can be achieved. It contributes to reduce the construction cost and to enhance the freedom of designing. Among the high-Cr ferritic steels, modified 9Cr-1Mo steel (compatible to ASTM A335 P91) is a candidate of the structural material for the demonstration facility of JSFR, because the steel has superior microstructure stability at elevated temperature for long time. However, remarkable creep strength degradation has been observed in the welded joint of high-Cr ferritic steels, especially in long-term region. It is known as "Type-IV damage". In the elevated temperature designing for the fast reactors, such creep strength degradation must be taken into account properly. Therefore, the creep strength assessment procedure and the allowable stress for the welded joints made of modified 9Cr-1Mo steel have been proposed. In this study, (1) a series of creep rupture tests to verify the validity of the creep strength assessment procedure was performed. (2) Applicability of the creep strength assessment procedure to the creep fatigue strength assessment of the welded joints made of modified 9Cr-1Mo steel was investigated. (3) Metallurgical examinations of creep ruptured specimens were carried out to confirm the contribution of "Type-IV damage". As a result, it was demonstrated that the creep strength assessment procedure was validated using the long-term creep rupture test results less than 30,000h and that the creep strength assessment procedure was applicable to the creep-fatigue strength assessment based on some uniaxial creep-fatigue test results.

Application of cathodic protection of stainless steel for components in fuel reprocessing plant

Ueno, Fumiyoshi; Uchiyama, Yohei*; Kato, Chiaki; Yamamoto, Masahiro; Ebina, Tetsunari*; Shimogawara, Shigeru*; Kano, Yoichi*

Nihon Genshiryoku Gakkai Wabun Rombunshi, 9(3), p.279 - 287, 2010/09

https://doi.org/10.3327/taesj.J09.035

An application of cathodic protection method with impressed current system to control corrosion of austenitic stainless steel in boiling nitric acid solution was studied to improve corrosion resistance of components in fuel reprocessing plant. Plate and tube type specimens made of ultra low carbon type 304 stainless steel (SUS304ULC) were immersed in boiling nitric acid solutions using electrochemical test cells, electrochemical potentiostatic tests and cathodic protection tests were performed. Corrosion rates in the solution with and without protection were measured. As the results, corrosion rates of plate type specimens with cathodic protection were decreased from 1/40 to 1/10 against without protection. In the case of tube type specimen, loss of outer surface thickness was decreased about 1/8, and no deviation of the loss was observed. Authors were concluded that cathodic protection method was expectative as one of the maintenance methods of components in fuel reprocessing plant.

Plan and reports of coupled irradiation (JRR-3 and JOYO of research reactors) and hot facilities work (WASTEF, JMTR-HL, MMF and FMF); R&D project on irradiation damage management technology for structural materials of long-life nuclear plant

Matsui, Yoshinori; Takahashi, Hiroyuki; Yamamoto, Masaya; Nakata, Masahito; Yoshitake, Tsunemitsu; Abe, Kazuyuki; Yoshikawa, Katsunori; Iwamatsu, Shigemi; Ishikawa, Kazuyoshi; Kikuchi, Taiji; et al.

JAEA-Technology 2009-072, 144 Pages, 2010/03

JAEA-Technology-2009-072.pdf:45.01MB

"R&D Project on Irradiation Damage Management Technology for Structural Materials of Long-life Nuclear Plant" was carried out from FY2006 in a fund of a trust enterprise of the Ministry of Education, Culture, Sports, Science and Technology. The coupled irradiations or single irradiation by JOYO fast reactor and JRR-3 thermal reactor were performed for about two years. The irradiation specimens are very important materials to establish of "Evaluation of Irradiation Damage Indicator" in this research. For the acquisition of the examination specimens irradiated by the JOYO and JRR-3, we summarized about the overall plan, the work process and the results for the study to utilize these reactors and some facilities of hot laboratory (WASTEF, JMTR-HL, MMF and FMF) of the Oarai Research-and-Development Center and the Nuclear Science Research Institute in the Japan Atomic Energy Agency.

A New method for separating the and isomers of C

Han, A. H.*; Wakahara, Takatsugu*; Maeda, Yutaka*; Akasaka, Takeshi*; Fujitsuka, Mamoru*; Ito, Osamu*; Yamamoto, Kazunori; Kako, Masahiro*; Kobayashi, Kaoru*; Nagase, Shigeru*

New Journal of Chemistry, 33(3), p.497 - 500, 2009/03

https://doi.org/10.1039/B808119K

A new chemical method can be applied to isolate the isomers of C. The photochemical cycloaddition of a mixture of C() and C() with disilirane affords only the mono-adduct of the isomer of C. The counter part (C()) does not give the mono-adduct with disilirane. The isomer itself and the adduct of the isomer of C with disilirane was easily separated by a HPLC procedure. A facile oxidative desilylation of the adduct took place, resulting in the formation of pristine C(). In this context, the separation and the isolation of two isomers of C() and C() were successfully accomplished by using a silylation-oxidative desilylation process.

Progress in R&D efforts on the energy recovery linac in Japan

Sakanaka, Shogo*; Ago, Tomonori*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; Harada, Kentaro*; Hiramatsu, Shigenori*; Honda, Toru*; et al.

Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.205 - 207, 2008/06

Future synchrotron light sources based on the energy-recovery linacs (ERLs) are expected to be capable of producing super-brilliant and/or ultra-short pulses of synchrotron radiation. Our Japanese collaboration team is making efforts for realizing an ERL-based hard X-ray source. We report recent progress in our R&D efforts.

Single-ended pelletron accelerator at JAERI-Tokai

Shimizu, Shigeru; Fujii, Katsutoshi; Kajimoto, Yoichi; Kawasaki, Tomokatsu; Yamamoto, Hideaki

Dai-16-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.32 - 35, 2004/02

no abstracts in English

Synthesis of sulfur-doped TiO by ion implantation

Umebayashi, Tsutomu; Yamaki, Tetsuya; Yamamoto, Shunya; Tanaka, Shigeru; Asai, Keisuke*

Transactions of the Materials Research Society of Japan, 28(2), p.461 - 464, 2003/06

TiO is promising as a photocatalytic material. However, it is active only under UV light irradiation because of its wide band gap (3.0 eV). We recently reported that sulfur (S) doping caused the optical absorption edge of TiO to be shifted into the lower energy region. Based on the theoretical analyses using first principles band calculations, mixing of the S 3p states with the valence band was found to contribute to the bandgap narrowing. In this study presented here, S-doped TiO was prepared by ion implantation and subsequent thermal annealing. S was implanted into the single crystals of rutile TiO with a fluence of 8 10 ions/cm. According to the results of RBS/channeling analysis, irradiation damage recovered after the annealing at 600 C in air. In the annealed crystal, S atoms occupied O sites to form Ti-S bonds, as assessed by XPS.

UV-ray photoelectron and ab initio band calculation studies on electronic structures of Cr- or Nb-ion implanted titanium dioxide

Umebayashi, Tsutomu; Yamaki, Tetsuya; Sumita, Taishi*; Yamamoto, Shunya; Tanaka, Shigeru; Asai, Keisuke*

Nuclear Instruments and Methods in Physics Research B, 206, p.264 - 267, 2003/05

https://doi.org/10.1016/S0168-583X(03)00740-7

Chromium (Cr) and niobium (Nb) were implanted into single-crystalline titanium dioxide (TiO; rutile). After annealing at 600C for the Cr-implanted sample or at 1000C for the Nb-implanted sample, the radiation damage was recovered. The implanted metals occupied titanium (Ti) sites in TiO to form metal-oxygen bonds. According to the ultraviolet-ray photoelectron spectra, a localized level due to the implanted metals was formed in band gap of both the crystals. This position was close to the VB edge for the Cr-doped TiO, while the Nb-doped TiO had the small peak far from the edge. This is in good agreement with the ab-initio band calculation results. It is considered that the midgap states of Cr- and Nb-doped TiO consist of the Cr t or Ti t state, respectively.