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Akiyama, Yoichi; Shibanuma, So; Yanagisawa, Kenichi*; Yamada, Taichi; Suzuki, Kenta; Yoshida, Moeka; Ono, Takahiro; Kawabata, Kuniaki; Watanabe, Kaho; Morimoto, Kyoichi; et al.
JAEA-Review 2023-015, 60 Pages, 2023/09
JAEA-Review-2023-015.pdf:4.78MB
Naraha Center for Remote Control Technology Development (NARREC) was established in Japan Atomic Energy Agency to promote a decommissioning work of Fukushima Daiichi Nuclear Power Station (Fukushima Daiichi NPS). NARREC consists of a Full-scale Mock-up Test Building and Research Management Building. Various test facilities are installed in these buildings for the decommissioning work of Fukushima Daiichi NPS. These test facilities are intended to be used for various users, such as companies engaged in the decommissioning work, research and development institutions, educational institutions and so on. The number of NARREC facility uses was 84 in FY2021. We participated booth exhibitions and presentations on the decommissioning related events. Moreover, we also contributed to the development of human resources by supporting the 6th Creative Robot Contest for Decommissioning. As a new project, "Narahakko Children's Classroom" was implemented for elementary school students in Naraha Town. This report summarizes the activities of NARREC in FY2021, such as the utilization of facilities and equipment of NARREC, the development of remote-control technologies for supporting the decommissioning work, arrangement of the remote-control machines for emergency response, and training for operators by using the machines.
Higashi, Yoichi*; Nagai, Yuki; Yoshida, Tomohiro*; Masaki, Yusuke*; Yanase, Yoichi*
Physical Review B, 93(10), p.104529_1 - 104529_10, 2016/03
Times Cited Count：11 Percentile：47.12(Materials Science, Multidisciplinary)no abstracts in English
Higashi, Yoichi*; Nagai, Yuki; Yoshida, Tomohiro*; Kato, Masaru*; Yanase, Yoichi*
Physica C, 518, p.1 - 4, 2015/11
Times Cited Count：0 Percentile：0(Physics, Applied)We study the excitation spectra and the wave functions of quasiparticle bound states at a vortex and an edge in bilayer Rashba superconductors under a magnetic field. In particular, we focus on the quasiparticle states at the zero energy in the pair- density wave state in a topologically non-trivial phase. We numerically demonstrate that the quasiparticle wave functions with zero energy are localized at both the edge and the vortex core if the magnetic field exceed the critical value.
Ito, Shinichi*; Yokoo, Tetsuya*; Masuda, Takatsugu*; Yoshizawa, Hideki*; Soda, Minoru*; Ikeda, Yoichi*; Ibuka, Soshi*; Kawana, Daichi*; Sato, Taku*; Nambu, Yusuke*; et al.
JPS Conference Proceedings (Internet), 8, p.034001_1 - 034001_6, 2015/09
Higashi, Yoichi*; Nagai, Yuki; Yoshida, Tomohiro*; Yanase, Yoichi*
Journal of Physics; Conference Series, 568(2), p.022018_1 - 022018_5, 2014/12
Times Cited Count：4 Percentile：82.5(Physics, Applied)We numerically study the electronic structure of a single vortex in two dimensional superconducting bilayer systems within the range of the mean-field theory. The lack of local inversion symmetry in the system is taken into account through the layer dependent Rashba spin-orbit coupling. The spatial profiles of the pair potential and the local quasiparticle density of states are calculated in the clean spin-singlet superconductor on the basis of the quasiclassical theory. In particular, we discuss the characteristic core structure in the pair-density wave state, which is spatially modulated exotic superconducting phase in a high magnetic field.
Kimura, Atsushi; Taguchi, Mitsumasa; Kondo, Takafumi*; Yang, J.*; Nagaishi, Ryuji; Yoshida, Yoichi*; Hirota, Koichi
Radiation Physics and Chemistry, 79(11), p.1159 - 1164, 2010/11
Times Cited Count：3 Percentile：24.08(Chemistry, Physical)Much of this past research has focused on finding more effective reactions between charged reactive species in room temperature ionic liquid (RTILs), which have a coulombic field. Reactions in RTILs involving the charged reactive species, particularly solvated electrons, have been studied by the techniques of radiation chemistry. The reaction behavior of halophenols in RTILs were investigated by 
ray and pulsed electron radiolysis. The yield of CP decomposition in the RTILs was almost the same as that of solvated electrons formation. The yield of CP decomposition and phenol formation in the RTILs was low in the presence of electron scavengers such as nitrous oxide, indicating that solvated electrons primarily contributed to the decomposition of CP. The type of halogen group with the exception of fluorine had a negligible effect on the decomposition of halophenols in the RTILs. Therefore, RTILs could be applied as an reaction media for the reduction by ionizing radiation.
Belloni, J.*; Crowell, R. A.*; Katsumura, Yosuke; Lin, M.; Marignier, J. L.*; Mostafavi, M.*; Muroya, Yusa*; Saeki, Akinori*; Tagawa, Seiichi*; Yoshida, Yoichi*; et al.
Recent Trends in Radiation Chemistry, p.121 - 160, 2010/05
In this review, we summarized development and application of highly time resolved spectroscopy system in order to measure radiation induced fast phenomena together with current status of the systems in the world.
Yoshida, Maiko; Sakamoto, Yoshiteru; Sueoka, Michiharu; Kawamata, Yoichi; Oyama, Naoyuki; Suzuki, Takahiro; Kamada, Yutaka; JT-60 Team
Fusion Engineering and Design, 84(12), p.2206 - 2213, 2009/12
Times Cited Count：17 Percentile：72.88(Nuclear Science & Technology)A fast charge exchange recombination spectroscopy (CXRS) system has been developed for the real-time measurement and feedback control of ion temperature (
) profile and toroidal rotation velocity (
) in JT-60U. In order to control and in real-time, the charge exchange recombination spectroscopy with high time resolution, the real-time processor system, and the real-time control system have been developed. Utilizing this system, real-time control of the gradient has been demonstrated with neutral beams at high beta plasmas. The strength of the internal transport barrier is controlled. Moreover, the real-time control of has been demonstrated from counter (anti parallel to the plasma current, 
) to co (parallel to the ) direction.
Kondo, Takafumi*; Asano, Akira*; Yang, J.*; Norizawa, Kimihiro*; Takahashi, Kenji*; Taguchi, Mitsumasa; Nagaishi, Ryuji; Kato, Ryuji*; Yoshida, Yoichi*
Radiation Physics and Chemistry, 78(12), p.1157 - 1160, 2009/12
Times Cited Count：28 Percentile：85.84(Chemistry, Physical)Spectrum and kinetic behavior of solvated electrons (e
) in alkyl ammonium ionic liquids (ILs), 
DEMMA-TFSI, DEMMA-BF4, TMPA-TFSI, PP13-TFSI, P13-TFSI and P14-TFSI were investigated by pulse radiolysis method. The e in the ILs have same absorption peak at 1100 nm with a molar absorption coefficient of 1.5-2.3
10
dm
mol
cm. The reaction rate constant of e with Pyrene (Py) was 1.5-3.510
dmmols. These values were about one order of magnitude higher than that of diffusion controlled limit, which was calculated from measured viscosity. The dry electron (e
) reacts with Py, and its rate constant in DEMMA-TFSI was 7.910
dmmols, three orders of magnitude higher than that of the e reactions.
Kimura, Atsushi; Taguchi, Mitsumasa; Kondo, Takafumi*; Yang, J.*; Yoshida, Yoichi*; Hirota, Koichi
Radiation Physics and Chemistry, 77(10-12), p.1253 - 1257, 2008/10
Times Cited Count：11 Percentile：59.16(Chemistry, Physical)Asano, Akira*; Yang, J.*; Kondo, Takafumi*; Norizawa, Kimihiro*; Nagaishi, Ryuji; Takahashi, Kenji*; Yoshida, Yoichi*
Radiation Physics and Chemistry, 77(10-12), p.1244 - 1247, 2008/10
Times Cited Count：25 Percentile：82.53(Chemistry, Physical)The molar extinction coefficient and the radiolytic yield of solvated electrons in ionic liquid of DEMMA-TFSI were estimated respectively to be 2.310 L mol cm and 0.810
mol J by observing the reaction and kinetics of solvated electron and dry electron in the ionic liquid. The solvated electron in DEMMA-TFSI has a very broad absorption spectrum peaking at 1100 nm and reacts slowly with pyrene with a rate constant of 3.510 L mol s, while the dry electron is captured rapidly by pyrene with C
value of 0.065 mol L.
Yang, J.*; Kondo, Takafumi*; Norizawa, Kimihiro*; Nagaishi, Ryuji; Taguchi, Mitsumasa; Takahashi, Kenji*; Kato, Ryuji*; Anishchik, S. V.*; Yoshida, Yoichi*; Tagawa, Seiichi*
Radiation Physics and Chemistry, 77(10-12), p.1233 - 1238, 2008/10
Times Cited Count：25 Percentile：82.53(Chemistry, Physical)First observation of picosecond dynamics in ionic liquid of DEMMA-TFSI in radiation chemistry was reported. It is found that the electron produced by ionization is solvated to full solvation in ionic liquid with a rate constant of 3.910
s. The yield of solvated electrons in picosecond time region is 1.210 mol J. The dry electron in ionic liquid reacts rapidly with biphenyl and pyrene with a rate constant of 3.8 to 7.910 L mol s. The geminate ion recombination in n-dodecane and n-hexane was also observed by monitoring the transient absorptions at 523 nm.
Kondo, Takafumi*; Yang, J.*; Kan, Koichi*; Yoshida, Yoichi*; Shibata, Hiromi*; Taguchi, Mitsumasa; Kojima, Takuji
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 160, 2008/03
no abstracts in English
Takenaga, Hidenobu; Kubo, Hirotaka; Sueoka, Michiharu; Kawamata, Yoichi; Yoshida, Maiko; Kobayashi, Shinji*; Sakamoto, Yoshiteru; Iio, Shunji*; Shimomura, Koji*; Ichige, Hisashi; et al.
Nuclear Fusion, 48(3), p.035011_1 - 035011_6, 2008/03
Times Cited Count：3 Percentile：13.2(Physics, Fluids & Plasmas)A burning plasma simulation scheme has been developed with consideration for temperature dependence of the DT fusion reaction rate in JT-60U. The heating power for the simulation of alpha particle heating was calculated using real-time measurements of density and ion temperature. Response of a simulated fusion gain to the density was investigated in this scheme with constant heating power for the simulation of external heating, in order to understand burn controllability by the fuel density in a fusion reactor. When temperature dependence of the fusion reaction rate was assumed as square of ion temperature, density dependence of the simulated fusion gain stronger than square of density was observed. Transport analysis using a 1.5 dimension transport code indicated that the strong density dependence is induced due to both change in a confinement improvement factor and change in a pressure profile.
Kato, Ryuji*; Yoshida, Yoichi*; Katsumura, Yosuke; Takahashi, Kenji*
Journal of Physical Chemistry B, 111(18), p.4770 - 4774, 2007/05
Times Cited Count：54 Percentile：76.97(Chemistry, Physical)Sugo, Yumi; Izumi, Yoshinobu*; Yoshida, Yoichi*; Nishijima, Shigehiro*; Sasaki, Yuji; Kimura, Takaumi; Sekine, Tsutomu*; Kudo, Hiroshi*
Radiation Physics and Chemistry, 76(5), p.794 - 800, 2007/05
Times Cited Count：78 Percentile：97.59(Chemistry, Physical)The radiolytic behavior of 
-tetraoctyldiglycolamide, 
-dimethyl--dioctyl-2-(3'-oxapentadecyl)malonamide, and 
-dioctylhexanamide in 
-dodecane was investigated by irradiation with -rays and electron pulses. The results showed -dodecane has a sensitization effect on the radiolysis of these amides, owing mainly to a charge transfer from radical cations of -dodecane to the amide molecules in the primary process observed in pulse radiolysis.
Kondo, Takafumi*; Yang, J.*; Kan, Koichi*; Yoshida, Yoichi*; Shibata, Hiromi*; Taguchi, Mitsumasa; Kojima, Takuji
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 141, 2007/02
no abstracts in English
Yoshida, Yoichi*; Yang, J.*; Kondo, Takafumi*; Seki, Shuhei*; Kozawa, Takahiro*; Tagawa, Seiichi*; Shibata, Hiromi*; Taguchi, Mitsumasa; Kojima, Takuji; Namba, Hideki
JAEA-Review 2005-001, TIARA Annual Report 2004, p.183 - 185, 2006/01
A heavy-ion-pulse radiolysis technology was developed using a single-photon-counting system. In the system, the ion beam was injected a thin scintillator before irradiating the sample. The light emitted from the scintillator by the ion irradiation was used as analyzing source to detect the absorption of primary species in water. Measurement of time-dependent absorption of hydrated electrons in water was achieved using the system, which demonstrates the usefulness of this technique.
Yoshida, Yoichi*; Yang, J.*; Saeki, Akinori*; Tagawa, Seiichi*; Shibata, Hiromi*; Namba, Hideki; Kojima, Takuji; Taguchi, Mitsumasa
JAERI-Review 2004-025, TIARA Annual Report 2003, p.143 - 144, 2004/11
no abstracts in English
Yonekawa, Izuru; Kawamata, Yoichi; Totsuka, Toshiyuki; Akasaka, Hiromi; Sueoka, Michiharu; Yoshida, Hidetoshi
Fusion Engineering and Design, 71(1-4), p.11 - 15, 2004/06
Times Cited Count：5 Percentile：35.25(Nuclear Science & Technology)The JT-60 control system based on workstation and VME-bus system features with UNIX system has been successfully performed at JT-60U advanced plasma experiment. The various hardware modifications and the adoption of the advanced plasma control algorithms have been continued to the JT-60 control system since its upgrade in 1991. The ZENKEI, supervisory control system, has entirely remodeled from its original 16 bits minicomputer and CAMAC system to the combination of workstation and VME-bus system configuration with Ethernet communication network system. The plasma control system executes real-time plasma equilibrium control command calculation within 250msec control cycle time. Each plant control subsystems are also modified along with same design concept to the ZENKEI. Currently, the minor modifications of the control system have been considered to realize longer pulse of discharge experiments without major change of the JT-60 equipment. Nearly 60 seconds of pulse length up to Ip=2MA, Bt=2T, PNBI=10MW(
30sec) plasma experiments will start from October in 2003.
