Structural investigation of borosilicate glasses by using XAFS measurement in soft X-ray region, 4 (Joint research)

Nagai, Takayuki; Okamoto, Yoshihiro; Shibata, Daisuke*; Kojima, Kazuo*; Hasegawa, Takehiko*; Sato, Seiichi*; Fukaya, Akane*; Hatakeyama, Kiyoshi*

JAEA-Research 2024-014, 54 Pages, 2025/02

JAEA-Research-2024-014.pdf:7.02MB

XAFS measurements in the soft X-ray region are suitable for evaluating the chemical state of the surface layer of a measurement sample because the X-ray transmittance is low. In this study, the purpose of the study was to confirm the difference between the coagulated surface layer and the inside of the simulated waste glasses by measuring the K-edge of the glass constituent elements boron, oxygen, sodium, and silicon, and the L edge of the waste component cerium. As a result, the B K-edge XANES spectra showed that the proportion of B-O tetracoordinate sp structures (BO) on the surface layer of the coagulated glass samples was higher than that on the cut surface inside the glass samples, which is expected to improve the water resistance of the coagulated surface. On the other hand, the O K-edge XANES spectra suggested that the O abundance in the coagulated surface layer was lower than that in the cut surface inside the glass samples, and that alkali metal elements may be concentrated in the coagulated surface layer. However, no difference was observed in the Na K-edge XANES spectra between the coagulated surface layer and the cut surface, and no difference was observed in the Si K-edge XANES spectra between the solidified surface and the inside of glass samples. In addition, the Ce L-edge XANES spectra confirmed that the Ce valence in the surface layer of coagulated glass samples were oxidized compared to the inside of glass samples.

Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2014); Development of recovery and mitigation technology on excavation damage (Contract research)

Fukaya, Masaaki*; Hata, Koji*; Akiyoshi, Kenji*; Sato, Shin*; Takeda, Nobufumi*; Miura, Norihiko*; Uyama, Masao*; Kaneda, Tsutomu*; Ueda, Tadashi*; Hara, Akira*; et al.

JAEA-Technology 2016-002, 195 Pages, 2016/03

JAEA-Technology-2016-002.pdf:46.3MB
JAEA-Technology-2016-002-appendix(CD-ROM).zip:16.11MB

The researches on examination of the plug applied to the future reflood test was conducted as a part of (5) development of technologies for restoration and/on reduction of the excavation damage relating to the engineering technology in the MIU (2014), specifically focused on (1) plug examination (e.g. functions, structure and material) and the quality control methods and (2) analytical evaluation of rock mass behavior around the plug through the reflood test. As the result, specifications of the plug were determined. These specifications should be able to meet requirements for the safety structure and surrounding rock mass against predicted maximum water pressure, temperature stress and seismic force, and for controlling the groundwater inflow, ensuring the access into the reflood gallery and the penetration performance of measurement cable. Also preliminary knowledge regarding the rock mass behavior around the plug after flooding the reflood gallery by installed plug was obtained.

Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2012) (Contract research)

Fukaya, Masaaki*; Noda, Masaru*; Hata, Koji*; Takeda, Nobufumi*; Akiyoshi, Kenji*; Ishizeki, Yoshikazu*; Kaneda, Tsutomu*; Sato, Shin*; Shibata, Chihoko*; Ueda, Tadashi*; et al.

JAEA-Technology 2014-019, 495 Pages, 2014/08

JAEA-Technology-2014-019.pdf:82.23MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) plan consists of (1) research on engineering technology deep underground, and (2) research on engineering technology as a basis of geological disposal. The former research is mainly aimed in this study, which is categorized in (a) development of design and construction planning technologies, (b) development of construction technologies, (c) development of countermeasure technologies, and (d) development of technologies for security. In this study, the researches on engineering technology are being conducted in these four categories by using data measured during construction as a part of the second phase of the MIU plan.

Hydraulic and migration study of the shallow accessible groundwater in biosphere modeling for HLW disposal

Inagaki, Manabu; Kato, Tomoko; Yoshida, Hideji*; Oyamada, Kiyoshi*; Fukaya, Yukiko*; Suzuki, Yuji*; Oi, Takao

JAEA-Research 2007-029, 81 Pages, 2007/03

JAEA-Research-2007-029.pdf:10.88MB

The project of high-level radioactive waste disposal is in activity for the site selection of HLW disposal facility and the performance assessment should be more site-specific rather than site-generic, where the applicability of the achievement of site-generic study such as second progress report (H12) to the site specific is to be clarified. In the same way, it is necessary for biosphere assessment to incorporate the site specific condition to the model. The exposure pathway or concentration of the radio nuclides should be determined according to the site specific geological condition, for example. In this paper, following topics have been selected to start the study to reflect specific geological condition to the biosphere modeling. (1) The literature survey of international and national approaches and issues relating to the treatment of GBIs within biosphere assessments, (2) To develop methodology to estimate the release point of the deep groundwater to the shallow accessible groundwater. (3) To prepare information to estimate water balance this is, in turn, necessary to assess the dilution and/or dispersion of the radionuclides in the shallow accessible groundwater body.

Mechanical properties of HIP bonded W and Cu-alloys joint for plasma facing components

Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Sato, Kazuyoshi

Journal of Nuclear Materials, 307-311(2), p.1542 - 1546, 2002/12

https://doi.org/10.1016/S0022-3115(02)01169-8

no abstracts in English

Development of bonding techniques between W and Cu-alloys for plasma facing components by HIP method, 3; Bonding tests with Au-foil insert

Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro

JAERI-Tech 2002-058, 30 Pages, 2002/07

JAERI-Tech-2002-058.pdf:2.56MB

no abstracts in English

Evaluation of properties of low activation Mn-Cr steel, 3; Evaluation of corrosion resistnace

Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Sato, Ikuo*; Kusuhashi, Mikio*; Hatakeyama, Tsuyoshi*; Takahashi, Heishichiro*; Kikuchi, Mitsuru

JAERI-Tech 2002-047, 51 Pages, 2002/05

JAERI-Tech-2002-047.pdf:3.42MB

no abstracts in English

Inspection of heat transfer tubes after mock-up tests of minituarized apparatus for the acid recovery evaporator (Contract research)

Hamada, Shozo; Fukaya, Kiyoshi*; Kato, Chiaki; Yanagihara, Takao; Doi, Masamitsu*; Kiuchi, Kiyoshi

JAERI-Tech 2001-063, 49 Pages, 2001/10

JAERI-Tech-2001-063.pdf:13.39MB

The demonstration test for the acid recovery evaporator and the dissolver used in the major equipment of Rokkasho Reprocessing Plant (RRP), has been carried out. The mock-up miniature equipment has been employed to it. This test had been performed from April in 1998. The total time of demonstration test using the mock-up equipment is about two and half years, which corresponds to about 20,000 hours. After that, four of the seven heat transfer tubes used in the evaporator were drawn out and the corrosion level and the mechanical properties were evaluated for one of them. As a result, intergranular corrosion was recognized in the inner surface of the heat transfer tube and the corrosion depth at the grain boundary was statistically shown to be about one grain from the inner surface. Further, no change in mechanical properties was observed and growth of intergranular cracks in the inner surface of the specimen was found after flattering test.

Development of experimental apparatus for evaluating corrosion resistance of clasing materials applied for advanced power reactor, 1

Inohara, Yasuto*; Ioka, Ikuo; Fukaya, Kiyoshi; Tachibana, Katsumi; Suzuki, Tomio; Kiuchi, Kiyoshi; Kuroda, Yuji*; Miyamoto, Satoshi*

JAERI-Tech 2001-021, 22 Pages, 2001/03

JAERI-Tech-2001-021.pdf:3.14MB

no abstracts in English

Mechanical properties of type 316L stainless steel welded joint for ITER vacuum vessel, 1; Experiment of unirradiated welded joint

Saito, Shigeru; Fukaya, Kiyoshi; Ishiyama, Shintaro; Takahashi, Hiroyuki*; Koizumi, Koichi

JAERI-Tech 2000-075, 98 Pages, 2001/01

JAERI-Tech-2000-075.pdf:21.85MB

no abstracts in English