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Watanabe, Masari*; Kurita, Nubuyuki*; Tanaka, Hidekazu*; Ueno, Wataru*; Matsui, Kazuki*; Goto, Takayuki*; Hagihara, Masato
Physical Review B, 105(5), p.054414_1 - 054414_12, 2022/02
Times Cited Count:1 Percentile:59.23(Materials Science, Multidisciplinary)Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; et al.
IEEE Transactions on Applied Superconductivity, 31(9), p.2400505_1 - 2400505_5, 2021/12
In this study, we employed a superconducting detector, current-biased kinetic-inductance detector (CB-KID) for neutron imaging using a pulsed neutron source. We employed the delay-line method, and high spatial resolution imaging with only four reading channels was achieved. We also performed wavelength-resolved neutron imaging by the time-of-flight method. We obtained the neutron transmission images of a Gd-Al alloy sample, inside which single crystals of GdAl were grown, using the delay-line CB-KID. Single crystals were well imaged, in both shapes and distributions, throughout the Al-Gd alloy. We identified Gd nuclei via neutron transmissions that exhibited characteristic suppression above the neutron wavelength of 0.03 nm. In addition, the
Gd resonance dip, a dip structure of the transmission caused by the nuclear reaction between an isotope and neutrons, was observed even when the number of events was summed over a limited area of 15
m
12
m. Gd selective imaging was performed using the resonance dip of
Gd, and it showed clear Gd distribution even with a limited neutron wavelength range of 1 pm.
Vu, TheDang; Shishido, Hiroaki*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; Miyajima, Shigeyuki*; et al.
Nuclear Instruments and Methods in Physics Research A, 1006, p.165411_1 - 165411_8, 2021/08
Times Cited Count:0 Percentile:0.02(Instruments & Instrumentation)Nishimura, Shoichiro*; Torii, Hiroyuki*; Fukao, Yoshinori*; Ito, Takashi; Iwasaki, Masahiko*; Kanda, Sotaro*; Kawagoe, Kiyotomo*; Kawall, D.*; Kawamura, Naritoshi*; Kurosawa, Noriyuki*; et al.
Physical Review A, 104(2), p.L020801_1 - L020801_6, 2021/08
Times Cited Count:7 Percentile:84.45(Optics)Vu, TheDang; Shishido, Hiroaki*; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Miyajima, Shigeyuki*; Oku, Takayuki; Soyama, Kazuhiko; Aizawa, Kazuya; et al.
Superconductor Science and Technology, 34(1), p.015010_1 - 015010_10, 2021/01
Times Cited Count:3 Percentile:48.97(Physics, Applied)Yano, Midori; Ito, Takayuki*; Tanaka, Yusuke*; Matsuoka, Daisuke*; Araki, Fumiaki*; Czauderna, T.*; Stephens, K.*
Proceedings of Joint International Conference on Supercomputing in Nuclear Applications + Monte Carlo 2020 (SNA + MC 2020), p.201 - 208, 2020/10
Visual analysis plays an important role in understanding and evaluating the climate models, their variables, and their outputs because complex processes are required for the tuning of the climate models. Virtual Reality (VR) technologies are effective for 3D visualization and have been recently employed for visual analysis of more various scientific data. However, researchers may have some problematic situations while using VR space depending on user operations and target geometries. Here, we propose an image-based view selection method to solve these situations and understand differences in ocean states between simulations and observations based on shapes of mode water regions. This view selection takes evaluation criteria for shape comparison of mode water regions generated from simulations and observations into account. This paper introduces two example cases applying this view selection and discusses on a degree of shape matching of mode water regions of each case.
Tanaka, Nobuyuki; Yamaki, Tetsuya*; Asano, Masaharu*; Terai, Takayuki*
Journal of Membrane Science, 587, p.117171_1 - 117171_9, 2019/10
Times Cited Count:10 Percentile:52(Engineering, Chemical)Electro-electrodialysis (EED) has been applied to thermochemical water-splitting iodine-sulfur process for hydrogen production in order to enhance the HI component in the HI-I-H
O mixture (HIx solution). In this paper, HIx solution concentration dependence of the conductivity (
) and transport number (
) as the membrane-performance indexes of Nafion 212 and a styrene-grafted poly(ethylene-co-tetrafluoroethylene) (ETFE) membrane was experimentally investigated. From the theoretical analysis for the measurements based on the new EED model, the effects of the H
and I
content and the diffusion coefficients of H
and I
in the evaluated membranes on
and
were as follows: HIx solution concentration dependence of ion contents exhibited a significantly small or different variation in comparison with that of
and t
, which indicates that the dominant factors for
and
would not be ion contents; thereby, the effect of ion diffusion coefficients should not be ruled out. For
of Nafion 212, H
diffusion is the dominant factor because the existence of I
was negligible, whereas for the ETFE-St membrane, the effect of I
diffusion should be considered. I
diffusion could more strongly affect
for the evaluated membranes rather than H
diffusion, which indicates that H
selectivity of the membranes could be relatively determined by the variation of the I
behavior in the membranes.
Strasser, P.*; Abe, Mitsushi*; Aoki, Masaharu*; Choi, S.*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; et al.
EPJ Web of Conferences, 198, p.00003_1 - 00003_8, 2019/01
Times Cited Count:12 Percentile:99.51Aratani, Hidekazu*; Nakatani, Yasuhiro*; Fujiwara, Hidenori*; Kawada, Moeki*; Kanai, Yuina*; Yamagami, Kohei*; Fujioka, Shuhei*; Hamamoto, Satoru*; Kuga, Kentaro*; Kiss, Takayuki*; et al.
Physical Review B, 98(12), p.121113_1 - 121113_6, 2018/09
Times Cited Count:3 Percentile:18.48(Materials Science, Multidisciplinary)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, Taiki*; Narikiyo, Yoshihiro*; Morita, Kosuke*; Fujita, Kunihiro*; Kaji, Daiya*; Morimoto, Koji*; Yamaki, Sayaka*; Wakabayashi, Yasuo*; Tanaka, Kengo*; Takeyama, Mirei*; et al.
Journal of the Physical Society of Japan, 87(1), p.014201_1 - 014201_9, 2018/01
Times Cited Count:14 Percentile:71.07(Physics, Multidisciplinary)Excitation functions of quasielastic scattering cross sections for the Ca +
Pb,
Ti +
Pb, and
Ca +
Cm reactions were successfully measured by using the gas-filled recoil-ion separator GARIS. Fusion barrier distributions were extracted from these data, and compared with the coupled-channels calculations. It was found that the peak energies of the barrier distributions for the
Ca +
Pb and
Ti +
Pb systems coincide with those of the 2n evaporation channel cross sections for the systems, while that of the
Ca +
Cm is located slightly below the 4n evaporation ones. This results provide us helpful information to predict the optimum beam energy to synthesize superheavy nuclei.
Nagai, Kodai*; Fujiwara, Hidenori*; Aratani, Hidekazu*; Fujioka, Shuhei*; Yomosa, Hiroshi*; Nakatani, Yasuhiro*; Kiss, Takayuki*; Sekiyama, Akira*; Kuroda, Fumiaki*; Fujii, Hitoshi*; et al.
Physical Review B, 97(3), p.035143_1 - 035143_8, 2018/01
Times Cited Count:20 Percentile:74.19(Materials Science, Multidisciplinary)We have studied the electronic structure of ferrimagnetic MnVAl single crystals by means of soft X-ray absorption spectroscopy (XAS), X-ray absorption magnetic circular dichroism (XMCD), and resonant soft X-ray inelastic scattering (RIXS). We have successfully observed the XMCD signals for all the constituent elements. The Mn L
XAS and XMCD spectra are reproduced by spectral simulations based on density-functional theory, indicating the itinerant character of the Mn 3
states. On the other hand, the V 3
electrons are rather localized since the ionic model can qualitatively explain the V L
XAS and XMCD spectra. This picture is consistent with local
excitations revealed by the V L
RIXS.
Kihara, Yoshiyuki; Tanaka, Kosuke; Koyama, Shinichi; Yoshimochi, Hiroshi; Seki, Takayuki; Katsuyama, Kozo
NEA/NSC/R(2017)3, p.341 - 350, 2017/11
In order to investigate the effect of the addition of americium to MOX fuels on the irradiation behaviour, the "Am-1" program is being conducted at the JAEA. The Am-1 program consists of two short-term irradiation tests of 10-min and 24-h irradiation periods, and a steady-state irradiation test. The short-term irradiation tests and their post irradiation examinations (PIEs) have been successfully completed. To date, the data for PIE of the Am-MOX fuels focused on the microstructural evolution and redistribution behaviour of Am at the initial stage of irradiation have been obtained and reported. In this paper, the results obtained from the Am-1 program are reviewed and detailed descriptions of the fabrication and inspection techniques for the Am-MOX fuels prepared for the program are provided. PIE data for the Am-MOX fuels at the initial stage of irradiation have been accumulated. In this paper, unpublished PIE data for the Am-MOX fuels are also presented.
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.
Kaji, Daiya*; Morita, Kosuke*; Morimoto, Koji*; Haba, Hiromitsu*; Asai, Masato; Fujita, Kunihiro*; Gan, Z.*; Geissel, H.*; Hasebe, Hiroo*; Hofmann, S.*; et al.
Journal of the Physical Society of Japan, 86(3), p.034201_1 - 034201_7, 2017/03
Times Cited Count:20 Percentile:79.07(Physics, Multidisciplinary)The fusion reaction of Ca +
Cm
Lv
was studied using the gas-filled recoil-ion separator GARIS at RIKEN. A total of seven
and spontaneous-fission decay chains were observed, which would originate from the reaction products of the element 116,
Lv and
Lv. Decay properties observed in the chains are in good agreement with the previously published ones. However, one of the chains showed a discrepancy, indicating the new spontaneous-fission branch in
Cn or the production of the new isotope
Lv.
Eichler, R.*; Asai, Masato; Brand, H.*; Chiera, N. M.*; Di Nitto, A.*; Dressler, R.*; Dllmann, Ch. E.*; Even, J.*; Fangli, F.*; Goetz, M.*; et al.
EPJ Web of Conferences, 131, p.07005_1 - 07005_7, 2016/12
Times Cited Count:2 Percentile:63.91In recent years gas-phase chemical studies assisted by physical pre-separation allowed for the productions and investigations of fragile single molecular species of superheavy elements. The latest highlight is the formation of very volatile hexacarbonyl compound of element 106, Sg(CO). Following this success, second-generation experiments were performed to measure the first bond dissociation energy between the central metal atom and the surrounding ligand. The method using a tubular decomposition reactor was developed and successfully applied to short-lived Mo(CO)
, W(CO)
, and Sg(CO)
.
Wakai, Eiichi; Watanabe, Kazuyoshi*; Ito, Yuzuru*; Suzuki, Akihiro*; Terai, Takayuki*; Yagi, Juro*; Kondo, Hiroo; Kanemura, Takuji; Furukawa, Tomohiro; Hirakawa, Yasushi; et al.
Plasma and Fusion Research (Internet), 11, p.2405112_1 - 2405112_4, 2016/11
Seki, Kotaro; Sasaki, Takayuki*; Akimoto, Yuji*; Tokunaga, Takahito; Tanaka, Kiwamu; Haraga, Tomoko; Ueno, Takashi; Ishimori, Kenichiro; Hoshi, Akiko; Kameo, Yutaka
JAEA-Technology 2016-013, 37 Pages, 2016/07
In this study, based on the simple and rapid analytical method established from the wastes from research facilities, we created analytical schemes which is applicable to rubble and plants collected at Fukushima Daiichi, then transported to Nuclear Science Research Institute of JAEA. We examined the applicability, and confirmed quantifiability of radioactivity concentration with high recovery rate without being affected by fission products such as Sr and
Cs.
Usoltsev, I.*; Eichler, R.*; Wang, Y.*; Even, J.*; Yakushev, A.*; Haba, Hiromitsu*; Asai, Masato; Brand, H.*; Di Nitto, A.*; Dllmann, Ch. E.*; et al.
Radiochimica Acta, 104(3), p.141 - 151, 2016/03
Times Cited Count:29 Percentile:95.75(Chemistry, Inorganic & Nuclear)Conditions of the production and decomposition of hexacarbonyl complexes of short-lived Mo and W isotopes were investigated to study thermal stability of the heaviest group 6 hexacarbonyl complex Sg(CO). A tubular flow reactor was tested to decompose the hexacarbonyl complexes and to extract the first bond dissociation energies. A silver was found to be the most appropriate reaction surface to study the decomposition of the group 6 hexacarbonyl. It was found that the surface temperature at which the decomposition occurred was correlated to the first bond dissociation energy of Mo(CO)
and W(CO)
, indicating that the first bond dissociation energy of Sg(CO)
could be determined with this technique.
Huang, M.*; Haba, Hiromitsu*; Murakami, Masashi*; Asai, Masato; Kaji, Daiya*; Kanaya, Jumpei*; Kasamatsu, Yoshitaka*; Kikunaga, Hidetoshi*; Kikutani, Yuki*; Komori, Yukiko*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 304(2), p.845 - 849, 2015/05
Times Cited Count:3 Percentile:28.28(Chemistry, Analytical)A technique to utilize radioisotopes of Nb and Ta was developed for chemical studies of element 105, Db, by coupling a gas-jet transport system to the RIKEN gas-filled recoil ion separator (GARIS). The short-lived Nb and
Ta were produced with nuclear reactions using a
F beam whose energy was the same as that to produce
Db. Then, they were separated with GARIS and extracted to a chemistry laboratory with the gas-jet transport system. By changing only magnetic field of GARIS and inserting an energy degrader and a shutter for recoil ions, we could deliver the
Nb and
Ta to a chemistry device for
Db without changing other experimental conditions.