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Fujihara, Masayoshi; Okabe, Hirotaka*; Koda, Akihiro*
Interactions (Internet), 245(1), p.13_1 - 13_6, 2024/12
Quantum states are difficult to observe experimentally. In addition, ideal model materials have not been found for some of the lattice systems in which exotic quantum states are predicted to be realized. Numerous candidates for low-dimensional quantum magnets are hidden in copper minerals, and the number of candidates is increasing every year. We succeeded to synthesize seven copper minerals by imitating the environment where they are discovered and reported their quantum states. The properties of pulsed muons are very suitable for investigating the spin state of artificial copper minerals.
Omokawa, Marina*; Kimura, Hiroyuki*; Hatsukawa, Yuichi*; Kawashima, Hidekazu*; Tsukada, Kazuaki; Yagi, Yusuke*; Naito, Yuki*; Yasui, Hiroyuki*
Bioorganic & Medicinal Chemistry, 97, p.117557_1 - 117557_6, 2024/01
Times Cited Count:0 Percentile:0.01(Biochemistry & Molecular Biology)Kirita, Fumio; Tominaga, Masahiro; Yamazaki, Toshihiko; Seshimo, Kazuyoshi; Uryu, Mitsuru
JAEA-Research 2022-006, 61 Pages, 2023/02
Nuclear Fuel Cycle Engineering Laboratories (NCL) has been observing ground motion for a long time. On the border from northern Ibaraki prefecture to Fukushima prefecture, inland crustal earthquakes occur less frequently until the 2011 off the Pacific coast of Tohoku Earthquake (hereinafter referred to as Tohoku Earthquake). After Tohoku Earthquake, aftershocks have become more frequent in this area, and in the Hamadori region of Fukushima earthquake that a remarkable long periodic component was observed in the NCL seismic observation record. Until now there were no such things that long periodic components were observed at the observation points near the epicenter of April 2011 Fukushima earthquake, but it was thought basin structure in deep basement around the NCL affected the propagation process to NCL by reflection survey result. As basement structure of NCL affected the seismic wave propagation process, the seismic wave repeatedly reflects and refracts. For that reason, long periodic components of seismic waves may be possibly amplified. In this study, in order to refine the long periodic ground motion evaluation, using a three dimensional ground structure model (3D model) that can reflect the shape of the deep basement structure around the NCL. When modeling 3D ground structure which has a width of about 80km and a length of about 110km and ranges from the epicenter area of April 2011 Fukushima earthquake to the northern coastal area of Ibaraki prefecture modeled, improved the optimum ground structure model using multiple observation records and performed simulation analysis.
Shirasaki, Kenji*; Tabata, Chihiro*; Sunaga, Ayaki*; Sakai, Hironori; Li, D.*; Konaka, Mariko*; Yamamura, Tomoo*
Journal of Nuclear Materials, 563, p.153608_1 - 153608_11, 2022/05
Times Cited Count:2 Percentile:53.91(Materials Science, Multidisciplinary)We focused on the direct synthesis of (U, )O solid solution (=Th, Np) by extending our recent progress in hydrothermal synthesis with additives. The homogeneity of the (U, )O ( = Th, Np) systems prepared by supercritical hydrothermal reactions was investigated through crystallographic analysis based on Vegard's law, and the Na nuclear magnetic resonance (NMR) measurement of (U, Np, Na)O solid solutions. Our experimental and analytical results revealed that (i) an optimal additive is ammonium carbonate and starting uranium valence is IV in the case of (U, Th)O, and (ii) an optimal additive is ethanol and starting uranium valence is VI in the case of (U, Np)O, for producing the homogeneous solid solutions by hydrothermal synthesis.
Tabata, Chihiro*; Shirasaki, Kenji*; Sunaga, Ayaki*; Sakai, Hironori; Li, D.*; Konaka, Mariko*; Yamamura, Tomoo*
CrystEngComm (Internet), 23(48), p.8660 - 8672, 2021/12
Times Cited Count:5 Percentile:64.74(Chemistry, Multidisciplinary)The hydrothermal synthesis of pure uranium dioxide under supercritical water (SCW) conditions was investigated. The nonstoichiometry, crystallite size and morphology of the UO particles were investigated. The SCW hydrothermal synthesis may be a promising method for producing homogeneous UO and its solid solutions with well-defined nonstoichiometries (), shapes, and sizes.
Schnaars, K.; Kaneko, Masashi; Fujisawa, Kiyoshi*
Inorganic Chemistry, 60(4), p.2477 - 2491, 2021/02
Times Cited Count:6 Percentile:59.03(Chemistry, Inorganic & Nuclear)To reduce high-level radiotoxic waste generated by nuclear power plants, highly selective separation agents for minor actinides are mandatory. The mixed N,O-donor ligand -tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine (HTPAEN) has shown good performance as a masking agent in Am/Eu separation studies. In this work, we examine whether a decrease in O-donor basicity can promote the M-N interactions. Therefore, we replace the deprotonated "charged" carboxylic acid groups of TPAEN by neutral amide groups and introduce -tetrakis[(6--diethylcarbamoylpyridin-2-yl)methyl]ethylenediamine (TPAMEN) as a new ligand. TPAMEN was crystallized with Eu(OTf) and Eu(NO) 6HO to form positively charged 1:1 [Eu(TPAMEN)] complexes in the solid state. Alterations in the M-O/N bond distances are compared to [Eu(TPAEN)] and investigated by DFT calculations to expose the differences in charge/energy density distributions at europium(III) and the donor functionalities of the TPAEN and TPAMEN. On the basis of estimations of the bond orders, atomic charges spin populations, and density of states in the Eu and potential Am and Cm complexes, the specific contributions of the donor-metal interaction are analyzed. The prediction of complex formation energy differences for the [M(TPAEN)] and [M(TPAMEN)] (M = Eu, Am) complexes provide an outlook on the potential performance of TPAMEN in Am/Eu separation.
Tsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Shintaro; Minato, Futoshi; Kawabata, Masako*; Hatsukawa, Yuichi*; Hashimoto, Kazuyuki*; Watanabe, Satoshi*; Saeki, Hideya*; Motoishi, Shoji*
Journal of the Physical Society of Japan, 89(3), p.034201_1 - 034201_7, 2020/03
Times Cited Count:2 Percentile:22.16(Physics, Multidisciplinary)We found anomalously large yields of Ga, Ga, Zn and Cu by neutron irradiation on a ZnO sample in a polyethylene shield. Neutron beams are generated from the Be() reaction for 50 MeV deuterons. The yields obtained were more than 20 times larger than those in the unshielded sample. On the other hand, the yields of Ga, Ga, Zn and Cu from a metallic Zn sample and the yields of Cu, Ni and Zn from the ZnO and Zn samples were almost insensitive to the shield conditions. This finding would provide us a unique capability of accelerator neutrons to simultaneously produce a large amount of several radioisotopes, including proton induced reaction products, by using a single sample. The experimental data were compared with the yields estimated by using the Particle and Heavy Ion Transport code System and the result was discussed.
Oishi, Tomoji*; Kimura, Yu*; Nakajima, Kiyohiko*; Watanabe, Masayuki; Aoyagi, Noboru
Materials Sciences and Applications, 11(3), p.195 - 203, 2020/03
A high-efficiency synthesis method for a latent pigment of red pigment diketo-pyrrolo-pyrrole (Pig. Red 272:272DPP), which is important as a functional organic pigment, was investigated, and the investigation results revealed that irradiation of microwaves (MWs) for several seconds to 272 DPP in NMP (N-methyl-2-pyrrolidone) solvent yielded DPP latent pigment (272DPP-BOC) at a high yield of 86.2%. Two kinds of latent-pigment crystals, namely, red and yellow, were obtained by recrystallization, and it was found that the fluorescence-emission properties of the two kinds differ significantly. Single-crystal X-ray structural analysis showed that the difference in the fluorescence-emission properties of the two types is derived from the difference in their crystal structures.
Wang, H.*; Otsu, Hideaki*; Chiga, Nobuyuki*; Kawase, Shoichiro*; Takeuchi, Satoshi*; Sumikama, Toshiyuki*; Koyama, Shumpei*; Sakurai, Hiroyoshi*; Watanabe, Yukinobu*; Nakayama, Shinsuke; et al.
Communications Physics (Internet), 2(1), p.78_1 - 78_6, 2019/07
Times Cited Count:8 Percentile:56.2(Physics, Multidisciplinary)Searching for effective pathways for the production of proton- and neutron-rich isotopes through an optimal combination of reaction mechanism and energy is one of the main driving forces behind experimental and theoretical nuclear reaction studies as well as for practical applications in nuclear transmutation of radioactive waste. We report on a study on incomplete fusion induced by deuteron, which contains one proton and one neutron with a weak binding energy and is easily broken up. This reaction study was achieved by measuring directly the cross sections for both proton and deuteron for Pd at 50 MeV/u via inverse kinematics technique. The results provide direct experimental evidence for the onset of a cross-section enhancement at high energy, indicating the potential of incomplete fusion induced by loosely-bound nuclei for creating proton-rich isotopes and nuclear transmutation of radioactive waste.
Segawa, Tomoomi
Funtai Kogakkai-Shi, 55(10), P. 547, 2018/10
no abstracts in English
Tashiro, Koji*; Kusaka, Katsuhiro*; Hosoya, Takaaki*; Ohara, Takashi; Hanesaka, Makoto*; Yoshizawa, Yoshinori*; Yamamoto, Hiroko*; Niimura, Nobuo*; Tanaka, Ichiro*; Kurihara, Kazuo*; et al.
Macromolecules, 51(11), p.3911 - 3922, 2018/06
Times Cited Count:5 Percentile:18.18(Polymer Science)Tsukada, Kazuaki; Nagai, Yasuki*; Hashimoto, Kazuyuki*; Kawabata, Masako*; Minato, Futoshi; Saeki, Hideya*; Motoishi, Shoji*; Ito, Masatoshi*
Journal of the Physical Society of Japan, 87(4), p.043201_1 - 043201_5, 2018/04
Times Cited Count:10 Percentile:60.27(Physics, Multidisciplinary)Nagai, Yasuki*; Tsukada, Kazuaki
Isotope News, (753), p.28 - 32, 2017/10
no abstracts in English
Nishio, Katsuhisa
Genshikaku Kenkyu, 62(1), p.89 - 94, 2017/09
no abstracts in English
Sugo, Yumi*; Hashimoto, Kazuyuki*; Kawabata, Masako*; Saeki, Hideya*; Sato, Shunichi*; Tsukada, Kazuaki; Nagai, Yasuki*
Journal of the Physical Society of Japan, 86(2), p.023201_1 - 023201_3, 2017/02
Times Cited Count:14 Percentile:68.14(Physics, Multidisciplinary)Cu produced by the Zn()Cu reaction was used for the first time to determine the biodistribution of CuCl in colorectal tumor-bearing mice. High uptake of Cu was observed in the tumor as well as in the liver and kidney which are the major organs for copper metabolism. The result showing Cu accumulation in the tumor suggests that CuCl can be a potential radionuclide agent for cancer radiotherapy. It would also encourage further studies on the therapeutic effect in small animals using an increased dose of Cu produced by the Zn()Cu reaction using intense neutrons available at present.
Ota, Masakazu; Katata, Genki; Nagai, Haruyasu; Terada, Hiroaki
Journal of Environmental Radioactivity, 162-163, p.189 - 204, 2016/10
Times Cited Count:7 Percentile:22.36(Environmental Sciences)Impacts of plant C uptake on (C) distributions around a nuclear facility were investigated by a land surface C model (SOLVEG-II). The simulation combined the SOLVEG-II with a mesoscale model and an dispersion model was applied to CO transfer at test operations of the Rokkasho reprocessing plant (RRP) in 2007. The calculated C-specific activities in rice grains agreed with the observations. Numerical experiment of chronic CO release from the RRP showed that C-specific activities of rice plants at harvest differed from the annual mean ones in the air, which was attributed to seasonal variations in atmospheric CO and plant growth. C accumulation in plant significantly increased when CO releases were limited during daytime, compared with the results observed during nighttime, due to extensive CO uptake by daytime photosynthesis. These results indicated that plant growth and photosynthesis should be considered in predictions of ingestion dose of C for long-term chronic and short-term diurnal releases of CO, respectively.
Ueda, Ryoshiro*; Sato, Katsuya; Hayashi, Hidenori*; Narumi, Issey*; Ono, Yutaka
JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 101, 2016/02
Takagi, Shigeyuki*; Iijima, Yuki*; Sato, Toyoto*; Saito, Hiroyuki; Ikeda, Kazutaka*; Otomo, Toshiya*; Miwa, Kazutoshi*; Ikeshoji, Tamio*; Aoki, Katsutoshi*; Orimo, Shinichi*
Angewandte Chemie; International Edition, 54(19), p.5650 - 5653, 2015/05
Times Cited Count:32 Percentile:68.44(Chemistry, Multidisciplinary)Moribayashi, Kengo
Physica Scripta, 90(5), p.054013_1 - 054013_5, 2015/05
Times Cited Count:5 Percentile:40.49(Physics, Multidisciplinary)Ueda, Ryoshiro; Sato, Katsuya; Hayashi, Hidenori*; Narumi, Issey*; Ono, Yutaka
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 118, 2015/03