Carrying-out of whole nuclear fuel materials in Plutonium Research Building No.1

Inagawa, Jun; Kitatsuji, Yoshihiro; Otobe, Haruyoshi; Nakada, Masami; Takano, Masahide; Akie, Hiroshi; Shimizu, Osamu; Komuro, Michiyasu; Oura, Hirofumi*; Nagai, Isao*; et al.

JAEA-Technology 2021-001, 144 Pages, 2021/08

JAEA-Technology-2021-001.pdf:12.98MB

Plutonium Research Building No.1 (Pu1) was qualified as a facility to decommission, and preparatory operations for decommission were worked by the research groups users and the facility managers of Pu1. The operation of transportation of whole nuclear materials in Pu1 to Back-end Cycle Key Element Research Facility (BECKY) completed at Dec. 2020. In the operation included evaluation of criticality safety for changing permission of the license for use nuclear fuel materials in BECKY, cask of the transportation, the registration request of the cask at the institute, the test transportation, formulation of plan for whole nuclear materials transportation, and the main transportation. This report circumstantially shows all of those process to help prospective decommission.

Prediction of the drying behavior of debris in Fukushima Daiichi Nuclear Power Station for dry storage

Nakayoshi, Akira; Suzuki, Seiya; Okamura, Nobuo; Watanabe, Masayuki; Koizumi, Kenji

Journal of Nuclear Science and Technology, 55(10), p.1119 - 1129, 2018/10

https://doi.org/10.1080/00223131.2018.1480429

Dynamics of ion internal transport barrier in LHD heliotron and JT-60U tokamak plasmas

Ida, Katsumi*; Sakamoto, Yoshiteru; Yoshinuma, Mikiro*; Takenaga, Hidenobu; Nagaoka, Kenichi*; Hayashi, Nobuhiko; Oyama, Naoyuki; Osakabe, Masaki*; Yokoyama, Masayuki*; Funaba, Hisamichi*; et al.

Nuclear Fusion, 49(9), p.095024_1 - 095024_9, 2009/09

https://doi.org/10.1088/0029-5515/49/9/095024

Dynamics of ion internal transport barrier (ITB) formation and impurity transport both in the Large Helical Device (LHD) heliotron and JT-60U tokamak are described. Significant differences between heliotron and tokamak plasmas are observed. The location of the ITB moves outward during the ITB formation regardless of the sign of magnetic shear in JT-60U and the ITB becomes more localized in the plasma with negative magnetic shear. In LHD, the low Te/Ti ratio ( 1) of the target plasma for the high power heating is found to be necessary condition to achieve the ITB plasma and the ITB location tends to expand outward or inward depending on the condition of the target plasmas. Associated with the formation of ITB, the carbon density tends to be peaked due to inward convection in JT-60U, while the carbon density becomes hollow due to outward convection in LHD. The outward convection observed in LHD contradicts the prediction by neoclassical theory.

None

*; *; *; *

PNC TJ1277 98-001, 204 Pages, 1998/02

PNC-TJ1277-98-001.pdf:6.59MB

None

Annual report on the environmental radiation monitoring around Tokai reprocessing plant; January - December, 1992

; ; ; ; Kano, Yutaka; Yoshida, Mika;

PNC TN8440 93-006, 157 Pages, 1993/03

PNC-TN8440-93-006.pdf:5.53MB

Environmental radiation monitoring around the Tokai Reprocessing Plant has been performed since 1975, based on "Safety Regulations for the Tokai Reprocessing Plant, Chapter VII - Environmental Monitoring". This annual report presents the results of the environmental monitoring and the dose estimation to the hypothetical inhabitants due to the radioactivity discharged from the plant during 1992. Appendices present comprehensive information, such as monitoring program, monitoring results, meteorological data and annual discharges from the plant.

KENO-IV Code Benchmark Calculation,9; Three Clusters of UO Rods Lattice

; ; Shimooke, Takanori; *

JAERI-M 9168, 34 Pages, 1980/11

JAERI-M-9168.pdf:2.21MB

no abstracts in English

Synthesis and luminescence properties of mononuclear Y(III), La(III), Gd(III) complexes with tetradentate Schiff base ligands derived from chiral stilbenediamine

Suzuki, Kaori*; Tsuchimoto, Masanobu*; Aoyagi, Noboru; Watanabe, Masayuki; Nakajima, Kiyohiko*

no journal, , 

Mononuclear Y(III), La(III), Gd(III) complexes ((CH)N[Ln(L)]) with tetradentate Schiff base ligands derived from chiral stilbenediamine were synthesized. The luminescence of these complexes exhibited different in luminescence color between the chiral complexes and the racemic complexes. In this presentation, luminescence properties on the crystalline powder of mononuclear Y(III), La(III), Gd(III) complexes were investigated in detail. It was found out that the different luminescence spectra of crystalline were observed in between chiral and racemic complexes, but the similar luminescence spectra were observed in the ground ones.

Benchmark experiment on copper with DT neutron source FNS

Kwon, Saerom*; Ota, Masayuki*; Sato, Satoshi*; Konno, Chikara; Ochiai, Kentaro*; Suzuki, Hiromitsu*

no journal, , 

Copper is used as a material for superconducting coil in magnetic confinement fusion reactor and for accelerator-driven neutron source such as IFMIF. Hence, well-reliable copper nuclear data is in high-priority study to achieve for their neutronics analyses. We carried out copper nuclear data benchmark experiment on copper assembly with LiO layers for interruption of background neutrons at JAEA/FNS, and measured reaction and fission rates using activation foils and micro fission chambers. The results were analyzed using MCNP-5.140 with the latest nuclear data libraries, JENDL-4.0, ENDF/B-VII.1 (FENDL-3.0) and JEFF-3.2. We found out that the calculated results related to threshold reactions agreed well the measured ones, but those related to low energy neutrons exceedingly underestimated the measured ones in the experiment. In order to resolve the underestimation issues, we pointed out that a drastic reassessment of cross sections of elastic scattering and capture reaction in the resonance region was unavoidable.

Drying characteristics of simulated debris in a pretreatment process for dry storage

Nakayoshi, Akira; Suzuki, Seiya; Okamura, Nobuo; Watanabe, Masayuki; Koizumi, Kenji

no journal, , 

Treatment policies for debris from Fukushima Daiichi Nuclear Power Plant is not decided, however, any policies may include medium and long term storages of debris. Dry storages may be desirable in terms of costs and handlings, but it is necessary to assess generating hydrogen during storages due to radiolysis of accompanied water with debris before debris storages. AlO, SiO, ZrO, UO and cement paste pellets as simulated debris were prepared, which have some porosities and pore. Weight changes of wet samples were measured at various drying temperatures (200, 300, and 1000 C) using a thermal gravity measurement, under helium gas flow (50 cc/min) or reduced pressure conditions (reducing pressure rate: 200 Pa in 30 min.). From the results, drying curves were evaluated.

Computational study on the extraction pattern of lanthanides with nitrilotriacetamide reagents

Kaneko, Masashi; Watanabe, Masayuki; Suzuki, Hideya; Matsumura, Tatsuro

no journal, , 

Nitrilotriacetamide (NTAamide) is considered to be a candidate for the separation reagent of minor-actinides (MA) from lanthanides (Ln) for an application to partitioning and transmutation. We have elucisdated the separation mechanism of Am from Eu with NTAamide by means of density functional theory (DFT). The present study applied the DFT method to Ln pattern of distribution ratio with NTAamide by solvent extraction. The extracted complex by NTAamide was modeled as [Ln(NTAamide)] (Ln = La, Ce, Nd, Sm, Eu, Gd) by referring the analogous crystal structure. Calculated geometry was indicated to belong to a pseudo-S point group with the Ln-N(amine) axis as C rotational axes. Gibbs energy difference indicated that NTAamide ligands more stably coordinate to light or middle Ln ions than La ion. This tendency was comparable to the experimental result of distribution ratio for Ln ions reported previously.