Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.
JAEA-Technology 2013-021, 43 Pages, 2013/07
The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.
Michimura, Shinji*; Inami, Toshiya; Matsuoka, Eiichi*; Watahiki, Masanori*; Tanigaki, Katsumi*; Onodera, Hideya*
Journal of the Physical Society of Japan, 81(4), p.044711_1 - 044711_5, 2012/04
Times Cited Count:4 Percentile:33.06(Physics, Multidisciplinary)Resonant X-ray diffraction experiments on CePdS were performed at the Ce- absorption edge to study the states of quadrupolar ordering below the ferromagnetic transition temperature = 6.3 K. The magnetic structure of CePdS was reported as a canted ferromagnetic structure with a canting angle of 51. It has therefore been pointed out that the complex magnetic structure arises from the simultaneous ordering of quadrupole moments. We observed the azimuthal angle dependence of the diffraction intensity of the two forbidden reflections 003 and 104 reflections for both -' and -' scattering processes. The results revealed that -type antiferroquadrupolar ordering coexists with magnetic ordering. We infer that the magnetic structure of CePdS is not a canted structure but a ferrimagnetic structure and that the quadrupole moment is also a primary-order parameter.
Watahiki, Masatoshi; Akai, Masanori; Nakai, Koji; Iemura, Keisuke; Yoshino, Masanori*; Hirano, Hiroshi*; Kitamura, Akihiro; Suzuki, Kazunori
Nihon Genshiryoku Gakkai Wabun Rombunshi, 11(1), p.101 - 109, 2012/02
Gloveboxes used for plutonium fuel development and fabrication are eventually dismantled for replacement or decommissioning. Since equipment interior and the inner surface of gloveboxes are contaminated in radioactive materials, glovebox dismantling work is performed by workers wearing an air fed suit with mechanical tools in a plastic enclosure system to control the spread of contamination. Various improvements of enclosure system are implemented including modification of the rooms to decontaminate and undress the air fed suit and introduction of inflammable filter and safety film near the size reduction workspace against fire. We describe the countermeasures deployed in the enclosure system against potential hazards and how these devices work in the real dismantling activities.
Imaizumi, Tomomi; Miyauchi, Masaru; Ito, Masayasu; Watahiki, Shunsuke; Nagata, Hiroshi; Hanakawa, Hiroki; Naka, Michihiro; Kawamata, Kazuo; Yamaura, Takayuki; Ide, Hiroshi; et al.
JAEA-Technology 2011-031, 123 Pages, 2012/01
The number of research reactors in the world is decreasing because of their aging. However, the planning to introduce the nuclear power plants is increasing in Asian countries. In these Asian countries, the key issue is the human resource development for operation and management of nuclear power plants after constructed them, and also the necessity of research reactor, which is used for lifetime extension of LWRs, progress of the science and technology, expansion of industry use, human resources training and so on, is increasing. From above backgrounds, the Neutron Irradiation and Testing Reactor Center began to discuss basic concept of a multipurpose low-power research reactor for education and training, etc. This design study is expected to contribute not only to design tool improvement and human resources development in the Neutron Irradiation and Testing Reactor Center but also to maintain and upgrade the technology on research reactors in nuclear power-related companies. This report treats the activities of the working group from July 2010 to June 2011 on the multipurpose low-power research reactor in the Neutron Irradiation and Testing Reactor Center and nuclear power-related companies.
Okano, Masanori; Kuno, Takehiko; Nemoto, Hirokazu*; Yamada, Keiji; Watahiki, Masaru; Hiyama, Toshiaki
Proceedings of INMM 50th Annual Meeting (CD-ROM), 9 Pages, 2009/07
no abstracts in English
Kuno, Takehiko; Nakamura, Yoshinobu; Okano, Masanori; Sato, Soichi; Watahiki, Masaru
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 3 Pages, 2005/10
The elemental composition and amount of insoluble materials in highly active liquid waste (HALW) were measured at the Tokai Reprocessing Plant. To evaluate the composition of the insoluble material between the treatment and storage processes, samples from the evaporator and two vessels which differ in the storage period, were taken. The concentration of insoluble material evaluated by both its weight on filter paper after filtration as well as by filtration volume showed no difference for three different samples. Inductively coupled plasma atomic emission spectrometry and isotope dilution mass spectrometry were used to determine the elements in samples dissolved by sulfate fusion. Analytical data revealed that Zr and Mo were the main components of the insoluble material in three samples, but low levels of Rh, Ru and Pd were also present. These results suggest that most of insoluble material had re-precipitated from the HALW solution during the concentration process.
Okano, Masanori; Kuno, Takehiko; Watahiki, Masaru; Yamada, Keiji; Kurakata, Koichiro
no journal, ,
no abstracts in English
Okano, Masanori; Kuno, Takehiko; Nemoto, Hirokazu*; Igarashi, Kazuto*; Yamada, Keiji; Watahiki, Masaru
no journal, ,
no abstracts in English
Kuno, Takehiko; Nemoto, Hirokazu*; Okano, Masanori; Igarashi, Kazuto*; Yamada, Keiji; Watahiki, Masaru
no journal, ,
no abstracts in English
Suzuki, Yutaka; Nemoto, Hirokazu*; Igarashi, Kazuto*; Okano, Masanori; Kuno, Takehiko; Yamada, Keiji; Watahiki, Masaru
no journal, ,
no abstracts in English
Michimura, Shinji; Inami, Toshiya; Matsuoka, Eiichi*; Watahiki, Masanori*; Tanigaki, Katsumi*; Onodera, Hideya*
no journal, ,
no abstracts in English
Suzuki, Yutaka; Kuno, Takehiko; Nemoto, Hirokazu*; Okano, Masanori; Goto, Yuichi; Igarashi, Kazuto*; Shimizu, Yasuyuki; Suda, Shizuka; Yamada, Keiji; Watahiki, Masaru
no journal, ,
no abstracts in English
Kuno, Takehiko; Okano, Masanori; Masui, Kenji; Suzuki, Yutaka; Yamada, Keiji; Watahiki, Masaru; Hiyama, Toshiaki
no journal, ,
no abstracts in English
Michimura, Shinji; Inami, Toshiya; Matsuoka, Eiichi*; Watahiki, Masanori*; Onodera, Hideya*
no journal, ,
Michimura, Shinji; Inami, Toshiya; Otsubo, Toru*; Matsumura, Takeshi*; Tanida, Hiroshi*; Sera, Masafumi*; Matsuoka, Eiichi*; Watahiki, Masanori*; Tanigaki, Katsumi*; Onodera, Hideya*
no journal, ,
Michimura, Shinji; Inami, Toshiya; Otsubo, Toru*; Matsumura, Takeshi*; Tanida, Hiroshi*; Sera, Masafumi*; Matsuoka, Eiichi*; Watahiki, Masanori*; Tanigaki, Katsumi*; Onodera, Hideya*
no journal, ,
no abstracts in English
Watahiki, Shunsuke; Ide, Hiroshi; Hanakawa, Hiroki; Yamaura, Takayuki; Kaminaga, Masanori
no journal, ,
no abstracts in English
Hanakawa, Hiroki; Watahiki, Shunsuke; Ide, Hiroshi; Kitagishi, Shigeru; Imaizumi, Tomomi; Araki, Daisuke; Tobita, Masahiro; Yamaura, Takayuki; Kaminaga, Masanori
no journal, ,
On 18th December 2013, the new regulatory requirements for Japanese research reactor were enforced by the Nuclear Regulation Authority in Japan. This new regulatory requirements are also applied to any research reactor in Japan, even if licensed research reactor. Thus the verification of conformity in the JMTR facilities to the new regulatory requirements was carried out. In this reports, the safety assessment against the beyond design basis accident will be described. At first, events tree analyses were carried out to select beyond design basis accidents. From these analyses, it was confirmed that 8 events can be representative cases. These events were analyzed from the viewpoints of public dose exposer. As the result of analysis, it was confirmed that 3 events out of 8 has a possibility to give the considerable public dose exposer so that the counter measerments were taken account to reduce the dose exposer to acceptable limit.
Kaminaga, Masanori; Takemoto, Noriyuki; Watahiki, Shunsuke
no journal, ,
no abstracts in English