Study on plutonium burner high temperature gas-cooled reactor in Japan; Introduction scenario, reactor safety and fabrication tests of the 3S-TRISO fuel

Ueta, Shohei; Mizuta, Naoki; Fukaya, Yuji; Goto, Minoru; Tachibana, Yukio; Honda, Masaki*; Saiki, Yohei*; Takahashi, Masashi*; Ohira, Koichi*; Nakano, Masaaki*; et al.

Nuclear Engineering and Design, 357, p.110419_1 - 110419_10, 2020/02

https://doi.org/10.1016/j.nucengdes.2019.110419

The concept of a plutonium (Pu) burner HTGR is proposed to incarnate highly-effective Pu utilization by its inherent safety features. The security and safety fuel (3S-TRISO fuel) employs the coated fuel particle with a fuel kernel made of plutonium dioxide (PuO) and yttria stabilized zirconia (YSZ) as an inert matrix. This paper presents feasibility study of Pu burner HTGR and R&D on the 3S-TRISO fuel.

Measurement and mechanism investigation of negative and positive muon-induced upsets in 65-nm Bulk SRAMs

Liao, W.*; Hashimoto, Masanori*; Manabe, Seiya*; Watanabe, Yukinobu*; Abe, Shinichiro; Nakano, Keita*; Sato, Hikaru*; Kin, Tadahiro*; Hamada, Koji*; Tampo, Motonobu*; et al.

IEEE Transactions on Nuclear Science, 65(8), p.1734 - 1741, 2018/08

https://doi.org/10.1109/TNS.2018.2825469

Soft error induced by secondary cosmic-ray muon is concerned since susceptibility of semiconductor device to soft error increases with the scaling of technology. In this study, we have performed irradiation tests of muons on 65-nm bulk CMOS SRAM in the Japan Proton Accelerator Research Complex (J-PARC) and measured soft error rate (SER) to investigate mechanism of muon-induced soft errors. It was found that SER by negative muon increases above 0.5 V supply voltage, although SER by positive muon increases monotonically as the supply voltage lowers. SER by negative muon also increases with forward body bias. In addition, negative muon causes large multiple cell upset (MCU) of more than 20 bits and the ratio of MCU events to all the events is 66% at 1.2V supply voltage. These tendencies indicate that parasitic bipolar action (PBA) is highly possible to contribute to SER by negative muon. Experimental data are analyzed by PHITS. It was found that negative muon can deposit larger charge than positive muon, and such events that can deposit large charge may trigger PBA.

Conceptual study of a plutonium burner high temperature gas-cooled reactor with high nuclear proliferation resistance

Goto, Minoru; Demachi, Kazuyuki*; Ueta, Shohei; Nakano, Masaaki*; Honda, Masaki*; Tachibana, Yukio; Inaba, Yoshitomo; Aihara, Jun; Fukaya, Yuji; Tsuji, Nobumasa*; et al.

Proceedings of 21st International Conference & Exhibition; Nuclear Fuel Cycle for a Low-Carbon Future (GLOBAL 2015) (USB Flash Drive), p.507 - 513, 2015/09

A concept of a plutonium burner HTGR named as Clean Burn, which has a high nuclear proliferation resistance, had been proposed by Japan Atomic Energy Agency. In addition to the high nuclear proliferation resistance, in order to enhance the safety, we propose to introduce PuO-YSZ TRISO fuel with ZrC coating to the Clean Burn. In this study, we conduct fabrication tests aiming to establish the basic technologies for fabrication of PuO-YSZ TRISO fuel with ZrC coating. Additionally, we conduct a quantitative evaluation of the security for the safety, a design of the fuel and the reactor core, and a safety evaluation for the Clean Burn to confirm the feasibility. This study is conducted by The University of Tokyo, Japan Atomic Energy Agency, Fuji Electric Co., Ltd., and Nuclear Fuel Industries, Ltd. It was started in FY2014 and will be completed in FY2017, and the first year of the implementation was on schedule.

Plasma regimes and research goals of JT-60SA towards ITER and DEMO

Kamada, Yutaka; Barabaschi, P.*; Ishida, Shinichi; Ide, Shunsuke; Lackner, K.*; Fujita, Takaaki; Bolzonella, T.*; Suzuki, Takahiro; Matsunaga, Go; Yoshida, Maiko; et al.

Nuclear Fusion, 51(7), p.073011_1 - 073011_11, 2011/07

https://doi.org/10.1088/0029-5515/51/7/073011

Report on ITPA (International Tokamak Physics Activity) meeting, 31

Suzuki, Takahiro; Isayama, Akihiko; Yoshida, Maiko; Aiba, Nobuyuki; Shinohara, Koji; Nakano, Tomohide; Kawano, Yasunori

Purazuma, Kaku Yugo Gakkai-Shi, 86(12), p.717 - 721, 2010/12

http://ci.nii.ac.jp/naid/40017444483

no abstracts in English

Charge collection properties of 6H-SiC diodes by wide variety of charged particles up to several hundreds MeV

Onoda, Shinobu; Iwamoto, Naoya; Murakami, Makoto; Oshima, Takeshi; Hirao, Toshio; Kojima, Kazutoshi*; Kawano, Katsuyasu*; Nakano, Itsuo*

Materials Science Forum, 615-617, p.861 - 864, 2009/00

no abstracts in English

In-core SCC growth behavior of type 304 stainless steel in BWR simulated high-temperature water at JMTR

Kaji, Yoshiyuki; Ugachi, Hirokazu; Tsukada, Takashi; Nakano, Junichi; Matsui, Yoshinori; Kawamata, Kazuo; Shibata, Akira; Omi, Masao; Nagata, Nobuaki*; Dozaki, Koji*; et al.

Journal of Nuclear Science and Technology, 45(8), p.725 - 734, 2008/08

https://doi.org/10.3327/jnst.45.725

Irradiation assisted stress corrosion cracking (IASCC) is one of the critical concerns when stainless steel components have been in service in light water reactors for a long period. In-core IASCC growth tests have been carried out using the compact tension type specimens of type 304 stainless steel that had been pre-irradiated up to a neutron fluence level around 110n/m in pure water simulated boiling water reactor (BWR) coolant condition at the Japan Materials Testing Reactor (JMTR). In order to investigate the effect of synergy of neutron/ radiation and stress/water environment on IASCC growth rate, we performed ex-core IASCC tests on irradiated specimens at several dissolved oxygen contents environments under the same electrochemical potential condition. In this paper, results of the in-core SCC growth tests will be discussed and compared with the result obtained by ex-core tests from a viewpoint of the synergistic effects on IASCC.

Prediction accuracy improvement of neutronic characteristics of a breeding light water reactor core by extended bias factor methods with use of FCA-XXII-1 critical experiments

Kugo, Teruhiko; Ando, Masaki; Kojima, Kensuke; Fukushima, Masahiro; Mori, Takamasa; Nakano, Yoshihiro; Okajima, Shigeaki; Kitada, Takanori*; Takeda, Toshikazu*

Journal of Nuclear Science and Technology, 45(4), p.288 - 303, 2008/04

https://doi.org/10.3327/jnst.45.288

The effectiveness of the extended bias factor methods, the LC and PE methods, is numerically investigated by applying them to a breeding light water reactor core as a target core with use of FCA-XXII-1 critical experiments. The present study numerically verifies the features of the extended bias factor methods. Both the methods can improve the prediction accuracy the most by using all the experiments. The PE method always improves the prediction accuracy with any combination of experiments. The PE method is always superior to the LC method for improvement of the prediction accuracy. From the present study, the followings are found. The experiments on multiplication factor are more applicable to a reaction rate ratio of U capture to Pu fission (C28/F49) of the target core than the experiments on C28/F49. Combinations of the experiments on multiplication factor is more effective to a void reactivity of the target core than those of the experiments on void reactivity though those on void reactivity are superior to those on multiplication factors in the case of using a single experiment. From these results, we conclude that the experiments on multiplication factor are more effective than the other experiments for all the neutronic characteristics of the target core. From these results, it is concluded that the PE method is promising to complement full mockup experiments for various future nuclear systems by using a number of existing and future benchmark experiments.

Collaboration of nuclear knowledge; Execution of science partnership project promoted by MEXT and repercussion effect obtained from the viewpoint of Intellectual collaboration

Yanagisawa, Kazuaki; Nagasawa, Naotsugu; Sasagawa, Sumiko*; Nakano, Koji*

JAEA-Review 2007-033, 171 Pages, 2007/09

JAEA-Review-2007-033-01.pdf:32.89MB
JAEA-Review-2007-033-02.pdf:29.9MB
JAEA-Review-2007-033-03.pdf:27.2MB
JAEA-Review-2007-033-04.pdf:12.21MB

The Fujioka Technical High School applied to the Science Partnership Project (SPP-2006) and asked an intellectual linkage with Japan Atomic Energy Agency (JAEA) and Institute for Environmental Sciences. Adding to normal lectures, the authors made several educational evaluations. For example, a change of student's interests through lectures on nuclear is evaluated. Direct comparison of intellectual ability between the students and 5 specialists are also made. Resultantly, if one teaches correctly the basic concept of nuclear energy and radiation application as learning inputs, an understanding ability of student increased 3 times than his previous background level. A comprehensive faculty of the students to the 5 specialists is 1/5 before making lecture but increased markedly to 1/2 after the lecture. A majority of students understand well the reprocessing, reactor accidents and food irradiation but showed poor understanding on the location and name of the commercial nuclear power plant and the basic mechanism of those.

Experimental progress on zonal flow physics in toroidal plasmas

Fujisawa, Akihide*; Ido, Takeshi*; Shimizu, Akihiro*; Okamura, Shoichi*; Matsuoka, Keisuke*; Hamada, Yasuji*; Hoshino, Katsumichi; Nagashima, Yoshihiko*; Shinohara, Koji; Nakano, Haruhisa*; et al.

Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 12 Pages, 2007/03

http://www-naweb.iaea.org/napc/physics/FEC/FEC2006/html/node104.htm#26311

Present status of experiments on zonal flows is overviewed. Innovative use of traditional and modern diagnostics has revealed unambiguously the existense of the zonal flows, their spatio-temporal caracteristics, their relationship with turbulence, and their effects on confinement. Particularly, a number of observations have been accumulated on the oscillatory branch of zonal flows, dubbed geodesic acoustic modes, suggesting necessity of theories to give their proper description. Furthur investigation of relationship between zonal flows and confinement is strongly encouraged as cross-device activity.