Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Yamaguchi, Akiko; Kurihara, Yuichi*; Nagata, Kojiro*; Tanaka, Kazuya; Higaki, Shogo*; Kobayashi, Toru; Tanida, Hajime; Ohara, Yoshiyuki*; Yokoyama, Keiichi; Yaita, Tsuyoshi; et al.
Journal of Colloid and Interface Science, 661, p.317 - 332, 2024/05
Times Cited Count:0no abstracts in English
Kondo, Yosuke*; Achouri, N. L.*; Al Falou, H.*; Atar, L.*; Aumann, T.*; Baba, Hidetada*; Boretzky, K.*; Caesar, C.*; Calvet, D.*; Chae, H.*; et al.
Nature, 620(7976), p.965 - 970, 2023/08
Times Cited Count:5 Percentile:92.64(Multidisciplinary Sciences)no abstracts in English
Wang, H.*; Yasuda, Masahiro*; Kondo, Yosuke*; Nakamura, Takashi*; Tostevin, J. A.*; Ogata, Kazuyuki*; Otsuka, Takaharu*; Poves, A.*; Shimizu, Noritaka*; Yoshida, Kazuki; et al.
Physics Letters B, 843, p.138038_1 - 138038_9, 2023/08
Times Cited Count:2 Percentile:68.16(Astronomy & Astrophysics)Detailed -ray spectroscopy of the exotic neon isotope Ne has been performed using the one-neutron removal reaction from Ne. Based on an analysis of parallel momentum distributions, a level scheme with spin-parity assignments has been constructed for Ne and the negative-parity states are identified for the first time. The measured partial cross sections and momentum distributions reveal a significant intruder p-wave strength providing evidence of the breakdown of the N = 20 and N = 28 shell gaps. Only a weak, possible f-wave strength was observed to bound final states. Large-scale shell-model calculations with different effective interactions do not reproduce the large p-wave and small f-wave strength observed experimentally, indicating an ongoing challenge for a complete theoretical description of the transition into the island of inversion along the Ne isotopic chain.
Yamaguchi, Akiko; Nagata, Kojiro*; Kobayashi, Keita; Tanaka, Kazuya; Kobayashi, Toru; Tanida, Hajime; Shimojo, Kojiro; Sekiguchi, Tetsuhiro; Kaneta, Yui; Matsuda, Shohei; et al.
iScience (Internet), 25(8), p.104763_1 - 104763_12, 2022/08
Times Cited Count:9 Percentile:68.46(Multidisciplinary Sciences)no abstracts in English
Yamaguchi, Akiko; Nagata, Kojiro*; Tanaka, Kazuya; Kobayashi, Keita; Kobayashi, Toru; Shimojo, Kojiro; Tanida, Hajime; Sekiguchi, Tetsuhiro; Kaneta, Yui; Matsuda, Shohei; et al.
Hosha Kagaku, (45), p.28 - 30, 2022/03
no abstracts in English
Tanaka, Masaru*; Kawara, Osami*; Ishizaka, Kaoru*; Ohata, Yuki*; Fukuike, Iori*; Kawase, Keiichi; Tokizawa, Takayuki; Miyagawa, Hiroshi*; Ishimori, Yuu
JAEA-Research 2018-001, 98 Pages, 2018/06
In the 2016 fiscal year, communication cases on general waste disposal facility construction plans in recent years were surveyed. Results suggested as follows: (1) Existing long-term relationships or agreements in local area promote local accepting. (2) An operator needs to consider alternative plans and explain reasons for the decision making to local stakeholders. (3) Even after first announcement of a new plan, an operator needs to review the plan depending on local concerns. (4) Announcement of a new plan will activate communications on local development including the site redevelopment.
Tanaka, Masaru*; Aoyama, Isao*; Ishizaka, Kaoru*; Ohata, Yuki*; Fukuike, Iori*; Kawase, Keiichi; Watanabe, Masanori; Tokizawa, Takayuki; Miyagawa, Hiroshi*; Ishimori, Yuu
JAEA-Research 2017-003, 65 Pages, 2017/06
JAEA Ningyo-toge Environmental Engineering Center and Fukushima Environmental Safety Center have same challenges in risk communication. As reference, similar domestic cases were investigated by our two Centers, and requirements for building long-term relationship were clarified. As follows; (1) Develop new relationship with various stakeholders in the region. (2) Make better use of existing resources (personnel, land and facilities, etc.). (3) Make a concerted effort to create new values with local stakeholders. (4) Make an opportunity which local stakeholders confirm safety and build confidence to the project. These efforts will enhance the opportunities for operators and residents to learn about environment management and environmental protection.
Kato, Atsushi; Nagai, Keiichi; Ara, Kuniaki; Otaka, Masahiko; Oka, Nobuki*; Tanaka, Masako*; Otani, Yuichi*; Ide, Akihiro*
Proceedings of 2017 International Congress on Advances in Nuclear Power Plants (ICAPP 2017) (CD-ROM), 8 Pages, 2017/04
In a fuel handling system (FHS) of a sodium-cooled fast reactor, it is necessary to reduce residual sodium on a spent fuel subassembly before storing at a spent fuel water-pool (SFP) in order to minimize design loads. Although the wet cleaning process adopted on MONJU could eliminate almost all of residual sodium, a large amount of radioactive liquid waste occurs and it needs long duration of cleaning treatment and large plant commodities. On the other hand, Japan sodium-cooled fast reactor adopted an advanced dry cleaning system which consists of roughly blowing massive sodium on the fuel subassembly out by 300C argon gas, inactivation of residual sodium to NaOH by moist argon gas and directly immersion into the SFP to achieve economic competitiveness and waste reduction. This paper reports current status of recent R&D activities to demonstrate a performance of the dry cleaning process in Japan which are for improvement of the cleaning performance and optimizing the FHS design.
Unno, Masayoshi*; Ishikawa, Kumiko*; Kusaka, Katsuhiro*; Tamada, Taro; Hagiwara, Yoshinori*; Sugishima, Masakazu*; Wada, Kei*; Yamada, Taro*; Tomoyori, Katsuaki; Hosoya, Takaaki*; et al.
Journal of the American Chemical Society, 137(16), p.5452 - 5460, 2015/04
Times Cited Count:28 Percentile:64.39(Chemistry, Multidisciplinary)Phycocyanobilin, a light-harvesting and photoreceptor pigment in higher plants, algae, and cyanobacteria, is synthesized from biliverdin IX (BV) by phycocyanobilin:ferredoxin oxidoreductase (PcyA) via two steps of two-proton-coupled two-electron reduction. We determined the neutron structure of PcyA from cyanobacteria complexed with BV, revealing the exact location of the hydrogen atoms involved in catalysis. Notably, approximately half of the BV bound to PcyA was BVH, a state in which all four pyrrole nitrogen atoms were protonated. The protonation states of BV complemented the protonation of adjacent Asp105. The "axial "water molecule that interacts with the neutral pyrrole nitrogen of the A-ring was identified. His88 N was protonated to form a hydrogen bond with the lactam O atom of the BV A-ring. His88 and His74 were linked by hydrogen bonds via HO. These results imply that Asp105, His88, and the axial water molecule contribute to proton transfer during PcyA catalysis.
Shibata, Masahiro; Sawada, Atsushi; Tachi, Yukio; Makino, Hitoshi; Wakasugi, Keiichiro; Mitsui, Seiichiro; Kitamura, Akira; Yoshikawa, Hideki; Oda, Chie; Ishidera, Takamitsu; et al.
JAEA-Research 2014-030, 457 Pages, 2015/03
JAEA and NUMO have conducted a collaborative research work which is designed to enhance the methodology of repository design and post-closure performance assessment in preliminary investigation stage. With regard to (1) study on rock suitability in terms of hydrology, based on some examples of developing method of hydro-geological structure model, acquired knowledge are arranged using the tree diagram, and model uncertainty and its influence on the evaluation items were discussed. With regard to (2) study on scenario development, the developed approach for "defining conditions" has been reevaluated and improved from practical viewpoints. In addition, the uncertainty evaluation for the effect of use of cementitious material, as well as glass dissolution model, was conducted with analytical evaluation. With regard to (3) study on setting radionuclide migration parameters, based on survey of precedent procedures, multiple-approach for distribution coefficient of rocks was established, and the adequacy of the approach was confirmed though its application to sedimentary rock and granitic rock. Besides, an approach for solubility setting was developed including the procedure of selection of solubility limiting solid phase. The adequacy of the approach was confirmed though its application to key radionuclides.
Ueno, Keiichiro*; Nagayoshi, Sanetaka*; Imakiire, Seiro*; Koriyama, Keisaku*; Minami, Tomohito*; Tanaka, Atsushi; Hase, Yoshihiro; Matsumoto, Toshikazu*
Engeigaku Kenkyu, 12(3), p.245 - 254, 2013/09
"Jimba" is a leading variety of white-flower chrysanthemum in Japan, although "Jimba" develops many axillary buds and also shows delayed flowering under a low temperature condition. Previously, we succeeded to produce new chrysanthemum variety "Aladdin" and "Imagine" that have a lesser number of axillary buds by ion beam irradiation. However, these varieties still show delayed flowering under a low temperature condition. In this study, we examined the effect of re-irradiation ofthese mutants by ion beams in improving flowering trait. The cultured leaves of "Aladdin" were irradiated with carbon ions and the regenerated plants were screened for the mutants that flowers earlier than the parental variety under a low temperature condition. Finally, we succeeded to produce new chrysanthemum variety "Aladdin 2" that develops a few axillary buds and shows early flowering traits. Thus, we demonstrated that the two important agronomic traits can be introduced by ion beam irradiation in a stepwise manner. The knowledge obtained in this study may be applicable for improving many kinds of plants.
Nakamura, Keisuke; Maeda, Makoto*; Yasumune, Takashi*; Maehata, Keisuke*; Ishibashi, Kenji*; Tanaka, Keiichi*; Umeno, Takahiro*; Takasaki, Koji; Momose, Takumaro
Radiation Protection Dosimetry, 146(1-3), p.88 - 91, 2011/07
Times Cited Count:1 Percentile:10.73(Environmental Sciences)A Transition Edge Sensor (TES) microcalorimeter has been developed for use as an energy dispersive X-ray spectrometer. A TES microcalorimeter is a thermal detector used to measure the energy of an incident photon with increase in temperature. In this work, a TES microcalorimeter with a 5m Au absorber was developed for use in measuring LX rays emitted from transuranium elements. Furthermore, as a cooling system a dilution refrigerator utilizing a Gifford-McMahon refrigerator was used, which needs no liquid helium. The performance of the TES microcalorimeter was evaluated by measuring the LX rays emitted by an Am source. This system proved effective in the measurement of the LX rays because the full width at half maximum of the LX ray was about 80 eV.
Iwamoto, Yosuke; Fukuda, Mitsuhiro*; Sakamoto, Yukio; Tamii, Atsushi*; Hatanaka, Kichiji*; Takahisa, Keiji*; Nagayama, Keiichi*; Asai, Hiroaki*; Sugimoto, Kenji*; Nashiyama, Isamu*
Nuclear Technology, 173(2), p.210 - 217, 2011/02
Times Cited Count:30 Percentile:89.69(Nuclear Science & Technology)The 30 white neutron beam at RCNP facility has been characterized as a prove suitable for testing of single event effects (SEEs) in semiconductors in the neutron energy range from 1 to 300 MeV using the 392-MeV proton incident reaction on a 6.5-cm-thick tungsten target. The neutron spectrum in measurements were demonstrated to provide a neutron spectrum similar to the terrestrial one at sea level, but with an enhancement in the intensity of a factor of 1.510. The average neutron intensity and spectrum from 10 to 300 MeV at RCNP were almost same as those at WNR. The calculated RCNP neutron flux using PHITS generally agreed with the measured RCNP data within a factor of two. As the neutron density per pulse for RCNP is 500 times lower than that for WNR, the pileup probability of single-event transient currents and false multiple-bit upsets is reduced. Such conditions at RCNP are suitable for accelerated SEE testing to get meaningful results in realistic time frame.
Maehata, Keisuke*; Nakamura, Keisuke*; Yasumune, Takashi*; Ishibashi, Kenji*; Takasaki, Koji; Tanaka, Keiichi*; Odawara, Akikazu*; Nagata, Atsushi*
Journal of Nuclear Science and Technology, 47(3), p.308 - 313, 2010/03
Times Cited Count:5 Percentile:35.74(Nuclear Science & Technology)A phase transition edge sensor (TES) microcalorimeter was developed for the energy dispersive measurement of LX-ray photons emitted from transuranium elements. The phase transition temperature of the TES was designed to be 200 mK by using bilayer structure of Au of 120 nm thick and Ti of 50 nm thick. The Au layer of 5.0 m thick was deposited on the Au/Ti bilayer for absorption efficiency of 50% and counting rate of 100 counts per second in the detection of LX-ray photons with the energy from 10 to 20 keV. The TES microcalorimeter was operated for the detection of LX-ray photons emitted from Am, Pu and Pu sources. The decay time constant of 180 s of detection signal pulses allowed the TES microcalorimeter operating with the counting rate higher than 100 counts per second. The energy resolution was obtained to be 50 eV of FWHM value for a peak corresponding to Np L X-ray of 17.75 keV.
Tojima, Futoshi*; Takenoshita, Yoshihisa*; Shirao, Tsukasa*; Nagatani, Takeshi*; Oe, Masakazu*; Ueno, Keiichiro*; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 73, 2008/03
no abstracts in English
Shirao, Tsukasa*; Ueno, Keiichiro*; Minami, Tomohito*; Tanaka, Akira*; Imakiire, Seiro*; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 74, 2008/03
no abstracts in English
Takagi, Keiichi*; Tanaka, Yoshikazu*; Hatashita, Masanori*; Endo, Nobuyuki*
Heisei-18-Nendo Zaidan Hojin Wakasawan Enerugi Kenkyu Senta Kenkyu Seika Hokokushu, 9, P. 95, 2007/09
no abstracts in English
Tominaga, Nozomu*; Maeda, Keiichi*; Umeda, Hideyuki*; Nomoto, Kenichi*; Tanaka, Masaomi*; Iwamoto, Nobuyuki; Suzuki, Tomoharu*; Mazzali, P. A.*
Astrophysical Journal, 657(2, Part2), p.L77 - L80, 2007/03
Times Cited Count:116 Percentile:91.98(Astronomy & Astrophysics)Long-duration -ray bursts (GRBs) are thought to be connected with luminous and energetic Type Ic supernovae [SNe, called hypernovae (HNe)] resulting from the black-hole (BH) forming collapse of massive stars. For GRBs 060505 and 060614, however, the expected SNe have not been detected. The upper limits to the SN brightness are about 100 times fainter than GRB-associated HNe (GRB-HNe), corresponding to the upper limits to the ejected Ni masses of Ni). SNe with a small amount of Ni ejection are observed as faint Type II SNe. HNe and faint SNe are thought to be responsible for the formaion of extremely metal-poor (EMP) stars. A relativistic jet-induced BH forming explosion of the 40 star is investigated and hydrodynamic and nucleosynthetic models are presented. These models can explain both GRB-HNe and GRBs without bright SNe in a unified manner. We suggest that GRBs without bright SNe are likely to synthesize Ni) or .
Tojima, Futoshi*; Shirao, Tsukasa*; Ueno, Keiichiro*; Oe, Masakazu*; Yasuniwa, Makoto*; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 83, 2007/02
no abstracts in English
Tanaka, Hirohisa*; Taniguchi, Masashi*; Uenishi, Mari*; Kajita, Nobuhiko*; Tan, Isao*; Nishihata, Yasuo; Mizuki, Junichiro; Narita, Keiichi*; Kimura, Mareo*; Kaneko, Kimiyoshi*
Angewandte Chemie; International Edition, 45(36), p.5998 - 6002, 2006/09
Times Cited Count:182 Percentile:94.91(Chemistry, Multidisciplinary)no abstracts in English