Generation of initial closed flux surface by ECH at conventional aspect ratio of R/a 3; Experiments on the LATE device and JT-60U tokamak

Uchida, Masaki*; Maekawa, Takashi*; Tanaka, Hitoshi*; Ide, Shunsuke; Takase, Yuichi*; Watanabe, Fumitake*; Nishi, Seiji*

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2010/10

http://www-naweb.iaea.org/napc/physics/FEC/FEC2010/html/node185.htm#40808

Application of PZC to W/Re generators

Matsuoka, Hiromitsu; Hashimoto, Kazuyuki; Hishinuma, Yukio*; Ishikawa, Koji*; Terunuma, Hitoshi*; Tatenuma, Katsuyoshi*; Uchida, Shoji*

Journal of Nuclear and Radiochemical Sciences, 6(3), p.189 - 191, 2005/12

https://doi.org/10.14494/jnrs2000.6.3_189

Applicability of Mo adsorbent PZC(Poly Zirconium Compound) for W/Re generator was investigated. Long term stability of adsorption of W to the PZC column, elution of Re from PZC column, desorption of from PZC column, and labeling of Hydroxyethylidene Diphosphonic Acid(HEDP) and Mercaptoacetyltriglycine(MAG3) with Re eluted from PZC column were tested. The PZC generator gave reproducible Re elution yields with low W parent breakthrough for a long period of time(about 5 months), that is the W/Re generator using PZC has a potential for practical use.

Study on Methodology for Biosphere Assessment Data

Kato, Tomoko; Suzuki, Yuji*; Makino, Hitoshi; Uchida, Masahiro; Naito, Morimasa; Wakasugi, Keiichiro*; Takahashi, Yoshiaki*

JNC TN1400 2005-024, 14 Pages, 2005/08

JNC-TN1400-2005-024.pdf:0.67MB

Biosphere assessment is positioned as part of an important factor in safety assessment to convert nuclide release rates into surface environment to measures of effect for human, such as radiation dose. In general, a lot of data are handled in the biosphere assessment, and they are based on the feature of specific site. Therefore, it is reasonable to screen parameters in order to manage the limited resource and develop the biosphere assessment effectively. JNC and NUMO established

Characterization of rust layer formed on Fe, Fe-Ni and Fe-Cr alloys exposed to Cl-rich environment by Cl and Fe K-edge XANES measurements

Konishi, Hiroyuki; Yamashita, Masato*; Uchida, Hitoshi*; Mizuki, Junichiro

Materials Transactions, 46(2), p.329 - 336, 2005/02

https://doi.org/10.2320/matertrans.46.329

Chloride in atmosphere considerably reduces the corrosion resistance of conventional weathering steel containing a small amount of Cr. Ni is an effective anticorrosive element for improving the corrosion resistance of steel in a Cl-rich environment. In order to clarify the structure of the protective rust layer of weathering steel, Cl and Fe K-edge X-ray absorption near edge structure (XANES) spectra of atmospheric corrosion products (rust) formed on Fe, Fe-Ni and Fe-Cr alloys exposed to Cl-rich atmosphere were measured. The Fe K-XANES measurements enable the characterization of a mixture of iron oxides such as rust. The chemical composition of the rust was determined by performing pattern fitting of the measured spectra. All the rust is composed mainly of goethite, akaganite, lepidocrocite and magnetite. Among these iron oxides, akaganite in particular is the major component in the rust. Additionally, the amount of akaganite in the rust of Fe-Ni alloy is much greater than that in rust of Fe-Cr alloy. Akaganite is generally considered to facilitate the corrosion of steel, but our results indicate that akaganite in the rust of Fe-Ni alloy is quantitatively different from that in rust of Fe-Cr alloy and does not facilitate the corrosion of steel. The shoulder peak observed in Cl K-XANES spectra reveals that the rust contains a chloride other than akaganite. The energy of the shoulder peak does not correspond to that of any well-known chlorides. In the measured spectra, there is no proof that Cl, by combining with the alloying element, inhibits the alloying element from acting in corrosion resistance. The shoulder peak appears only when the content of the alloying element is lower than a certain value. This suggests that the generation of the unidentified chloride is related to the corrosion rate of steel.

Cl K-edge XANES spectra of atmospheric rust on Fe, Fe-Cr and Fe-Ni alloys exposed to saline environment

Konishi, Hiroyuki; Yamashita, Masato*; Uchida, Hitoshi*; Mizuki, Junichiro

Materials Transactions, 45(12), p.3356 - 3359, 2004/12

https://doi.org/10.2320/matertrans.45.3356

Cl K-edge XANES measurements of atmospheric corrosion products (rust) formed on Fe, Fe-Ni and Fe-Cr alloys in chloride pollution have been performed using synchrotron radiation in order to clarify roles of anticorrosive alloying elements and of Cl in the corrosion resistance of weathering steel. The spectra of binary alloys show a shoulder structure near the absorption edge. The intensity of the shoulder peak depends on the kind and amount of the alloying element, whereas the energy position is invariant. This indicates that Cl is not combined directly with alloying elements in the rust.

Biosphere Assessment for High-level Radioactive Waste Disposal: Modelling Experinces and Discussion on Key Parameters by Sensitivity Analysis in JNC

Kato, Tomoko; Suzuki, Yuji*; Makino, Hitoshi; Uchida, Masahiro

Proceedings of International Symposium on Radioecology and Environmental Dosimetry, p.465 - 472, 2003/10

Considering a wide range of Japanese geological environments in generic context, some biosphere models were developed using an approach consistent with the BIOMASS Methodology. Moreover, sensitivity analysis for the biosphere models was performed to evaluate and understand the relative importance of parameters.

Development of JNC Geologic Disposal Technical Information Integration System -An Approach to Integrate and Share Technical Information among Safety Assessment, Repository Design and Site Investigation

Uchida, Masahiro; Makino, Hitoshi; Wakasugi, Keiichiro; Shibata, Katsushi

OECD/NEA Amigo Project Dai-1-Kai Wakushoppu, 0 Pages, 2003/00

None

Structural analysis of corrosion product of Fe-Cr alloy film using synchrotron radiation

Yamashita, Masato*; Konishi, Hiroyuki; Takahashi, Masamitsu; Mizuki, Junichiro; Uchida, Hitoshi*

Materials Science Research International, Special Technical Publication, 1, p.398 - 401, 2001/05

A rust layer on a weathering low-alloy steel has strong protective ability for atmospheric corrosion of the steel. In order to control the rust layer on steels, it is so important to know the detailed structure of rust and relate it to the protective ability of the rust layer. Especially, the position of atoms of the alloying elements in the rust layer directly control the structure and properties of the rust layer. We tried to find the atomic arrangement of the rust layer of Fe-Cr alloy film covered with thin film of electrolyte using synchrotron radiation. Grazing incidence X-ray diffraction and Mssbauer spectra showed that the rust layer was composed of -FeOOH and ultra-fine -FeOOH. By examining EXAFS spectra, Cr coming from Fe-Cr alloy film would be present in the -FeOOH. Some of Cr would be present between Fe-0-OH octahedron as interstitial atoms, as well as substituting Fe lattice site in the octahedron.

Uptake and transport of positron-emitting tracer (F) in plants

Kume, Tamikazu; Matsuhashi, Shimpei; ; Ito, Hitoshi; Fujimura, Takashi; ; Uchida, Hiroshi*; Ishioka, Noriko; Matsuoka, Hiromitsu; Osa, Akihiko; et al.

Applied Radiation and Isotopes, 48(8), p.1035 - 1043, 1997/00

https://doi.org/10.1016/S0969-8043(97)00117-6

no abstracts in English

Dismantlement of receiving and storage process equipment for transportation of spent fuels

Saegusa, Yu; Nishino, Saki; Horie, Koji; Yatabe, Hitoshi; Yamada, Takashi; Oyama, Daisuke; Uchida, Naoki

no journal, , 

All the spent fuel stored in the Tokai Reprocessing Plant is transported to the overseas reprocessing plant. When spent fuel transportation, we use dry type cask instead of wet type cask. Therefore, equipment of the wet type cask is not used. And the equipment is some possibility of interfere with cask because the equipment is stored in the transport route. So, we were dismantled receiving and storage process equipment as preparation work for spent fuel transportation. In dismantlement work, we selected cutting equipment after scrutinizing size and shape of equipment, contamination and workability. Moreover, we have taken safety measures during work such as fire prevention and contamination control. As a result, the work was completed as originally planned.