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Oishi, Kazuki*; Igarashi, Daisuke*; Tatara, Ryoichi*; Kawamura, Yukihiko*; Hiroi, Kosuke; Suzuki, Junichi*; Umegaki, Izumi*; Nishimura, Shoichiro*; Koda, Akihiro*; Komaba, Shinichi*; et al.
Journal of Physics; Conference Series, 2462, p.012048_1 - 012048_5, 2023/03
Times Cited Count：0 Percentile：0.21(Physics, Applied)Sugiyama, Daisuke*; Nakabayashi, Ryo*; Tanaka, Shingo*; Koma, Yoshikazu; Takahatake, Yoko
Journal of Nuclear Science and Technology, 58(4), p.493 - 506, 2021/04
Times Cited Count：2 Percentile：30.55(Nuclear Science & Technology)Sugiyama, Daisuke*; Nakabayashi, Ryo*; Koma, Yoshikazu; Takahatake, Yoko; Tsukamoto, Masaki*
Journal of Nuclear Science and Technology, 56(9-10), p.881 - 890, 2019/09
Times Cited Count：4 Percentile：40.43(Nuclear Science & Technology)Sugiyama, Daisuke*; Kimura, Hideo; Tachikawa, Hirokazu*; Iimoto, Takeshi*; Kawata, Yosuke*; Ogino, Haruyuki*; Okoshi, Minoru*
Journal of Radiological Protection, 38(1), p.456 - 462, 2018/03
Times Cited Count：0 Percentile：0.01(Environmental Sciences)Experience after the accident at the Fukushima Daiichi Nuclear Power Station has shown that there is a need to establish radiation protection criteria for radioactive waste management consistent with the criteria adopted for the remediation of existing exposure situations. A stepwise approach to setting such criteria is proposed. Initially, a reference level for annual effective dose from waste management activities in the range 1-10 mSv should be set, with the reference level being less than the reference level for ambient dose. Subsequently, the reference level for annual effective dose from waste management activities should be reduced in one or more steps to achieve a final target value of 1 mSv. The dose criteria at each stage should be determined with relevant stakeholder involvement. Illustrative case studies show how this stepwise approach might be applied in practice.
Koma, Yoshikazu; Sugiyama, Daisuke*; Ashida, Takashi
Proceedings of International Conference on the Safety of Radioactive Waste Management (Internet), p.153_1 - 153_4, 2016/11
To investigate accident waste management at the Fukushima Daiichi Nuclear Power Station, a methodology of inventory estimation for whole waste including those generated through D&D is indispensable and requires a calculation model. At early stage with insufficient analytical data of waste, a model should be developed by using knowledge of past experience from literature. Uncertainty in estimation shall be decreased based on analytical data available.
Kobayashi, Yasushi; Yamada, Tsutomu; Naito, Morimasa; Yui, Mikazu; Nakayama, Masashi; Sato, Haruo; Nishida, Takahiro*; Hironaga, Michihiko*; Yamamoto, Takeshi*; Sugiyama, Daisuke*; et al.
JAEA-Research 2009-013, 70 Pages, 2009/06
JAEA-Research-2009-013.pdf:8.85MB
Cementitious materials will be used to ensure construction and operational safety and work efficiency in a deep geological repository. The low alkaline cement has been developed to reduce uncertainties due to hyper alkaline for the long-term safety performance of the repository system. Functions of cementitious material required in each phase of repository construction, operation and closure were summarized in a separate report entitled "Application Study on Low Alkaline Cementitious Materials for Deep Geological Repository of High Level Radioactive Wastes (Phase I) "In this report, properties of low alkaline cement/concrete which have been developed both at home and abroad, and recipes of the low alkaline concrete taken account of application to the repository component have been investigated. Fresh and hardened properties of the low alkaline cement are equivalent to the OPC and the low alkaline cement has an advantage over OPC in terms of leaching resistance. The HFSC developed by JAEA, which belongs to a pozzolanic type low alkaline cement will be able to apply to the shotcrete and the lining concrete by choosing an adequate recipe. Clarification of influences of the chemical composition of groundwater on leachate properties of the hydrates, examination of pH measurement of cement leachate, evaluation of corrosion behavior of rebar embedded in the HFSC concrete are raised as open questions for future activities.
Kobayashi, Yasushi; Yamada, Tsutomu; Naito, Morimasa; Yui, Mikazu; Nakayama, Masashi; Sato, Haruo; Nishida, Takahiro*; Hironaga, Michihiko*; Yamamoto, Takeshi*; Sugiyama, Daisuke*; et al.
JAEA-Research 2008-112, 43 Pages, 2009/03
JAEA-Research-2008-112.pdf:4.58MB
In deep geological repository, use of cementitious material for rock support, lining, and grouting is essential for construction and operation and possibly raises in groundwater pH due to leachate from the cements. Since this hyperalkaline condition may lead to degradation of barriers, there is concern that it gives significant impact on long-term safety performance of the repository system. Because of these backgrounds, developments of low alkaline cement have been conducted both at home and abroad. JAEA is now planning to conduct an in-situ test for shotcreting using low alkaline cement at the Horonobe URL. On the other hand, CRIEPI has studied and developed cementitious materials for disposal of radioactive wastes. This joint research report summarizes requirements and expected performance of cementitious materials in repository taking account of surrounding conditions in each stage of the repository program so as to reflect them to further development of the low alkaline cement.
; The de Haas-van Alphen study under pressureSettai, Rikio*; Kubo, Tetsuo*; Shiromoto, Tomoyuki*; Honda, Daisuke*; Shishido, Hiroaki*; Sugiyama, Kiyohiro*; Haga, Yoshinori; Matsuda, Tatsuma; Betsuyaku, Kiyoshi*; Harima, Hisatomo*; et al.
Journal of the Physical Society of Japan, 74(11), p.3016 - 3026, 2005/11
Times Cited Count：62 Percentile：87.38(Physics, Multidisciplinary)We have studied a change of the Fermi surface in an antiferromagnet CeIn via the de Haas-van Alphen experiment under pressure up to 3 GPa. With increasing pressure P, the Neel temperature 
=10 K decreases and becomes zero at a critical pressure Pc 
2.6 GPa. In the pressure region 
, we have observed a large main Fermi surface named a, which indicates that the electronic state of 4 f electron in CeIn changes from localized to itinerant at Pc, as observed in the similar antiferromagnets CeRh
Si and CeRhIn
. The cyclotron effective mass 
of this main Fermi surface is extremely enhanced around Pc: 60 
at 2.7 GPa for the magnetic field along the 
100
direction.
Ueda, Taiki*; Honda, Daisuke*; Shiromoto, Tomoyuki*; Metoki, Naoto; Honda, Fuminori*; Kaneko, Koji; Haga, Yoshinori; Matsuda, Tatsuma; Takeuchi, Tetsuya*; Thamizhavel, A.*; et al.
Journal of the Physical Society of Japan, 74(10), p.2836 - 2842, 2005/10
Times Cited Count：15 Percentile：62.67(Physics, Multidisciplinary)Miya, Naoyuki; Watanabe, Daisuke*; Sakawa, Yoichi*; Shibahara, Takahiro*; Sugiyama, Kazuyoshi*; Shoji, Tatsuo*; Yamazaki, Kozo*; Masaki, Kei; Tanabe, Tetsuo*
no journal, ,
no abstracts in English
Oi, Takao; Uchiyama, Hideaki*; Ashida, Takashi; Meguro, Yoshihiro; Koma, Yoshikazu; Sugiyama, Daisuke*
no journal, ,
Inventory evaluation methods for the radioactive wastes of Fukushima Daiichi Nuclear Power Station has been developed. In this presentation, prior to presentation (4) to (8), outline of the project related to the study on the treatment and the disposal of the waste, importance of the developments of inventory evaluation methods in such project will be explained. Furthermore, the outline of following presentation will be introduced.
Meguro, Yoshihiro; Kato, Jun; Oi, Takao; Koma, Yoshikazu; Ashida, Takashi; Sugiyama, Daisuke*; Nakabayashi, Ryo*; Fujita, Tomonari*; Tsukamoto, Masaki*; Uchiyama, Hideaki*; et al.
no journal, ,
Inventory evaluation results obtained by analytical results of contaminated water was compared with that obtained on the basis of an analytically-calculated method for the secondary wastes generated from the water treatment system such as the cesium adsorption device, the second cesium adsorption device and the coagulating sedimentation device in the Fukushima Daiichi Nuclear Power Station.
Sugiyama, Daisuke*; Koma, Yoshikazu; Takahatake, Yoko; Aoki, Yoshio*; Nakabayashi, Ryo*; Fujita, Tomonari*
no journal, ,
The introduction of a stochastic approach to the calibration of the radionuclide transport parameters, which processes the frequency distribution of the analytical measured data accumulated progressively on the wastes and contaminated water, into the modelling estimation method of the radioactive waste inventory generated at the Fukushima Daiichi Nuclear Power Station is investigated. It is expected that the accuracy of the modelling estimation of radionuclide composition in wastes will be improved by describing the radionuclide transport parameters as a lognormal distribution.
Sugiyama, Daisuke*; Nakabayashi, Ryo*; Koma, Yoshikazu; Takahatake, Yoko; Aoki, Yoshio*
no journal, ,
no abstracts in English
Sugiyama, Koichi*; Go, Shintaro*; Tomimatsu, Taro*; Kai, Tamito*; Nagae, Daisuke*; Ishibashi, Yuichi*; Matsunaga, Sotaro*; Nagata, Yuto*; Nishibata, Hiroki*; Washiyama, Kohei*; et al.
no journal, ,
We have successfully performed in-beam gamma-ray spectroscopy using the isomer-scope technique to study excited-state structure of neutron-rich heavy-actinide nuclei. The neutron-rich heavy-actinide nuclei were produced in the multinucleon-transfer reactions with a 
Cm target and 
O projectiles accelerated with the JAEA tandem accelerator. Projectile-like scattered particles were detected with Si E-
E telescopes placed at the backward angle, and target-like scattered particles of isomers were caught by an annular aluminum plate placed at about 60-mm downstream from the target. Four Ge detectors and 4 LaBr detectors were placed at the periphery of the aluminum plate, and detected gamma rays from the isomers. Gamma rays emitted from the actinide isomers were successfully observed with a good sensitivity owing to the tungsten shield placed between the target and the detectors.
