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.

Measurements of neutron total and capture cross sections of Am with ANNRI at J-PARC

Terada, Kazushi*; Kimura, Atsushi; Nakao, Taro*; Nakamura, Shoji; Mizuyama, Kazuhito*; Iwamoto, Nobuyuki; Iwamoto, Osamu; Harada, Hideo; Katabuchi, Tatsuya*; Igashira, Masayuki*; et al.

Journal of Nuclear Science and Technology, 55(10), p.1198 - 1211, 2018/10

AA2017-0628.pdf:2.06MB

https://doi.org/10.1080/00223131.2018.1485519

Developments of a new data acquisition system at ANNRI

Nakao, Taro; Terada, Kazushi; Kimura, Atsushi; Nakamura, Shoji; Iwamoto, Osamu; Harada, Hideo; Katabuchi, Tatsuya*; Igashira, Masayuki*; Hori, Junichi*

EPJ Web of Conferences, 146, p.03021_1 - 03021_4, 2017/09

https://doi.org/10.1051/epjconf/201714603021

A new data acquisition system (DAQ system) in J-PARC Materials and Life Science Experimental Facility (MLF) ANNRI was developed. Increasing beam power of MLF in recent years allows beam line users to obtain high quantity experimental data yields. Compared to 2008, more than 20 times beam current is achieved in 2015. For the purpose to correspond strong beam power of MLF, a new DAQ system for the array of the Ge detectors in ANNRI is developed. The DAQ system is also going to be used for processing signals from a Li glass detector, which is under development at ANNRI for measurement of total neutron cross sections. Commissioning experiment of a new DAQ system at ANNRI was performed by using 0.1mmt Au sample with 500kW J-PARC proton beam power. An applicability of time-of-flight method for both neutron capture and total cross-sections measurements was checked. ADC and TDC nonlinearity, energy resolution, multi-channel coincidence and dead time performance for the array of the Ge detectors were also evaluated. The dead time value for Ge detectors was successfully decreased to 1/4 from the previous DAQ system with minor deterioration on energy resolution. The author would like to thank the accelerator and technical staff at J-PARC for operation of the accelerator and the neutron production target and for the other experimental supports. Present study includes the result of "Research and Development for accuracy improvement of neutron nuclear data on minor actinides" entrusted to the Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT).

Applicability of polyvinylpolypyrrolidone adsorbent to treatment process of wastes containing uranium

Ohashi, Yusuke; Harada, Masayuki*; Asanuma, Noriko*; Ando, Shion; Tanaka, Yoshio; Ikeda, Yasuhisa*

Journal of Radioanalytical and Nuclear Chemistry, 311(1), p.491 - 502, 2017/01

https://doi.org/10.1007/s10967-016-5017-9

In order to assess the feasibility of method for recovering U from wastes containing uranium (scrap uranium) using polyvinylpolypyrrolidone (PVPP) adsorbent, we have examined the adsorption and desorption behavior of metal species in HCl aqueous solutions dissolving scrap uranium. It was found that the U(VI) species are selectively adsorbed onto PVPP regardless of the presence of a large amount of Na(I) and Al(III), that the adsorbed U(VI) species are desorbed from PVPP column selectively by water. Pure uranium was efficiently recovered from the eluates. From these results, the PVPP resin is expected to be used as the adsorbent in the treatment process of scrap uranium.

Studies on electrochemical behavior of uranium species in choline chloride-urea eutectic for developing electrolytically treating method of uranium-bearing wastes

Ohashi, Yusuke; Asanuma, Noriko*; Harada, Masayuki*; Tanaka, Yoshio; Ikeda, Yasuhisa*

Journal of Radioanalytical and Nuclear Chemistry, 309(2), p.627 - 636, 2016/08

https://doi.org/10.1007/s10967-015-4625-0

As one of methods for recovering uranium from the uranium-bearing wastes, we have proposed the electrolytic deposition method using choline chloride-urea (CCU) which is known as an ambient temperature molten salt. More than 92% of uranium components in inactivated alumina and spent sodium fluoride adsorbent was dissolved into CCU solution. Cyclic voltammograms (CVs) of the solutions prepared by dissolving uranium-bearing wastes in CCU were measured in the potential range of -2.0 to 1.1 V (vs. Ag/AgCl). The one reduction peak was observed around -0.7 V for all solutions. Based on the results of CVs, bulk electrolyses of the solutions dissolving uranium-bearing wastes were also carried out at -1.5V at 80 C. The deposits were formed on a carbon electrode as cathode. Consequently, we confirmed that CCU is effective media for recovering uranium selectively from uranium-bearing waste.

R&D of the heat measurement method for accurate determination of amount of minor actinides samples for accuracy improvement of neutron nuclear data

Nakao, Taro; Nakamura, Shoji; Terada, Kazushi; Kimura, Atsushi; Harada, Hideo; Igashira, Masayuki*; Katabuchi, Tatsuya*; Hori, Junichi*

JAEA-Conf 2015-003, p.303 - 306, 2016/03

https://doi.org/10.11484/jaea-conf-2015-003

In spite of that the precise information of the total amount of the measurement sample is required for the neutron capture cross-section determination, it is not always performed in sufficient accuracy. Therefore, it is necessary to determine the absolute amount of samples accurately with non-destructively. This presentation will report on the future plan about the heat deposit measurement from minor actinides samples in order to determine the absolute amount of samples non-destructively, especially about the radiation shielding which is a unique problem of RI sample case. Also report about the result of the benchmark test measurement using Am -ray standard source. Present study includes the result of "Research and Development for accuracy improvement of neutron nuclear data on minor actinides" entrusted to the Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT).

Current activities and future plans for nuclear data measurements at J-PARC

Kimura, Atsushi; Harada, Hideo; Nakamura, Shoji; Iwamoto, Osamu; Toh, Yosuke; Koizumi, Mitsuo; Kitatani, Fumito; Furutaka, Kazuyoshi; Igashira, Masayuki*; Katabuchi, Tatsuya*; et al.

European Physical Journal A, 51(12), p.180_1 - 180_8, 2015/12

https://doi.org/10.1140/epja/i2015-15180-2

Correlation between intermolecular hydrogen bonds and melting points of uranyl nitrate complexes with cyclic urea derivatives

Suzuki, Tomoya; Takao, Koichiro*; Kawasaki, Takeshi*; Harada, Masayuki*; Nogami, Masanobu*; Ikeda, Yasuhisa*

Polyhedron, 96, p.102 - 106, 2015/08

https://doi.org/10.1016/j.poly.2015.04.034

We have determined crystal structures of UO(NO)() (: 2-imidazolidone), UO(NO)() (: tetrahydro-2-pyrimidone) and UO(NO)() (: 1-methyl-2-imidazolidone) by using single crystal X-ray analysis, and examined correlations between melting points (mps) and intermolecular hydrogen bonds (HBs) of UO(NO)(CU) (CU: cyclic urea derivatives) and UO(NO)(NRP) (NRP: pyrrolidone derivative).

Accuracy improvement of neutron nuclear data on minor actinides

Harada, Hideo; Iwamoto, Osamu; Iwamoto, Nobuyuki; Kimura, Atsushi; Terada, Kazushi; Nakao, Taro; Nakamura, Shoji; Mizuyama, Kazuhito; Igashira, Masayuki*; Katabuchi, Tatsuya*; et al.

EPJ Web of Conferences, 93, p.06001_1 - 06001_5, 2015/05

https://doi.org/10.1051/epjconf/20159306001

Improvement of accuracy of neutron nuclear data for minor actinides (MAs) and long-lived fission products (LLFPs) is required for developing innovative nuclear system transmuting these nuclei. In order to meet the requirement, the project entitled as "Research and development for Accuracy Improvement of neutron nuclear data on Minor ACtinides (AIMAC)" has been started as one of the "Innovative Nuclear Research and Development Program" at October 2013. The AIMAC project team is composed of researchers in four different fields: differential nuclear data measurement, integral nuclear data measurement, nuclear chemistry, and nuclear data evaluation. By integrating all of the forefront knowledge and techniques in these fields, the team aims at improving the accuracy of the data. The background, overall plan, and recent progress of the AIMAC project will be reviewed.

Response function for the measurement of (n,) reactions with the ANNRI-Cluster Ge detectors at J-PARC

Hara, Kaoru; Goko, Shinji*; Harada, Hideo; Hirose, Kentaro; Kimura, Atsushi; Kin, Tadahiro*; Kitatani, Fumito; Koizumi, Mitsuo; Nakamura, Shoji; Toh, Yosuke; et al.

JAEA-Conf 2014-002, p.88 - 92, 2015/02

https://doi.org/10.11484/jaea-conf-2014-002