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Yamasaki, Kazuhiko*; Kato, Hironori*; Futakawa, Masatoshi; Teshigawara, Makoto
Jikken Rikigaku, 21(4), p.308 - 313, 2021/12
In this study, coloration and damage of radiation-resistant lead glasses by nanosecond pulse laser with visible wavelength are evaluated. Three kinds of radiation resistance glasses with different lead content: PbO-55 wt%, 71 wt% and PbO free glass are used. As a result, the transitional coloration and damage formation with phase differences had observed by nanosecond pulsed laser irradiation at peak power of 1 kW. Although high-lead concentration glass has lower thresholds for coloration in laser intensity, damage-formation thresholds for both PbO glasses were almost the same. On the other hand, no change was observed after laser-irradiation to PbO-free glass. In addition, photochemical and thermal reaction of PbO by nanosecond pulsed laser irradiation is considered from the result of intensity change at wave numbers 200-500 and 1000 cm in Raman spectrums.
Hama, Katsuhiro; Mikake, Shinichiro; Ishibashi, Masayuki; Sasao, Eiji; Kuwabara, Kazumichi; Ueno, Tetsuro; Onuki, Kenji*; Beppu, Shinji; Onoe, Hironori; Takeuchi, Ryuji; et al.
JAEA-Review 2015-024, 122 Pages, 2015/11
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technical basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase III, as the Phase II was concluded for a moment with the completion of the excavation of horizontal tunnels at GL-500m level in February 2014. This report presents the results of the investigations, construction and collaboration studies in fiscal year 2014.
Funaki, Hironori; Ishiyama, Koji*; Waseda, Amane*; Kato, Susumu*; Watanabe, Kunio*
Chigaku Zasshi, 121(6), p.929 - 945, 2012/12
Molecular and carbon isotope compositions of hydrocarbon gas have information related to their generation, migration and accumulation, and serve evaluations of gas permeability in sedimentary rocks. We conducted headspace gas analysis at the cores (below 500 m depth) to evaluate gas permeability in Neogene sedimentary rocks in the Horonobe, Hokkaido, Japan. As a result, it was shown that hydrocarbon gases were almost biogenic methane. Further analysis of these data indicated that concentration and carbon isotope of methane varied carbon isotopic fractionation during anaerobic microbial oxidation and migration near the faults. A formation of high concentration and light carbon isotope of methane at present in the study area is low gas permeability and is less affected by secondary post-generic process.
Ueno, Fumiyoshi; Shiraishi, Hironori; Inoue, Shun; Motooka, Takafumi; Kato, Chiaki; Yamamoto, Masahiro; Uchiyama, Gunzo; Nojima, Yasuo*; Fujine, Sachio*
Proceedings of 20th International Conference on Nuclear Engineering and the ASME 2012 Power Conference (ICONE-20 & POWER 2012) (DVD-ROM), 8 Pages, 2012/07
In PUREX process for spent fuel reprocessing plants, heating portions in the components are severely corroded in the boiling solution under heat transfer (HT) conditions. In this paper, authors have focused on the effects of surface temperature and heat flux on corrosion rates (CRs) of stainless steels in boiling nitric acid under HT conditions. Two types of cells for HT and immersion conditions were applied for corrosion tests. Test solution used was 33 mol/m vanadium added to 3 kmol/m nitric acid solution, and was heated at boiling temperature under atmospheric pressure. Additionally, a boiling curve which was indicated the relation between heat flux and degree of superheating was investigated experimentally. Surface temperatures during corrosion tests were estimated from a boiling curve. The results showed that CR did not depend on heat flux, but depended on surface temperature. Arrhenius plots on CRs indicated that CR was accelerated by solution boiling against non-boiling.
Matsumura, Takeshi*; Inami, Toshiya; Kosaka, Masashi*; Kato, Yoshiaki*; Inukai, Takaki*; Ochiai, Akira*; Nakao, Hironori*; Murakami, Yoichi*; Katano, Susumu*; Suzuki, Hiroyuki*
Journal of the Physical Society of Japan, 77(10), p.103601_1 - 103601_4, 2008/10
Times Cited Count:14 Percentile:62.95(Physics, Multidisciplinary)Kato, Harukazu*; Tsuruta, Takuya*; Nishioka, Takashi*; Matsumura, Masahiro*; Sakai, Hironori; Kambe, Shinsaku
Journal of Physics and Chemistry of Solids, 68(11), p.2187 - 2190, 2007/11
Times Cited Count:8 Percentile:38.69(Chemistry, Multidisciplinary)Cu nuclear quadrupole resonance (NQR) studies have been carried out for CaCuRuO,which has been suggested to show a heavy-fermion-like behavioral though it possess no f electron. A Lorentzian shape of the Cu NQR line with a narrow width implies that no magnetic ordering appears, at least, down to 5 K. The spin-lattice relaxation rate of the Cu nuclei probes a change of the Cu 3 electron nature, resulting in the Fermi liquid state at a low temperature. These facts strongly support that the heavy fermion picture is available in the concerned compound.
Kambe, Shinsaku; Sakai, Hironori; Kato, Harukazu*; Tokunaga, Yo; Fujimoto, Tatsuya*; Walstedt, R. E.*; Ikeda, Shugo; Maehira, Takahiro*; Haga, Yoshinori; Onuki, Yoshichika
Physical Review B, 76(2), p.024411_1 - 024411_6, 2007/07
Times Cited Count:6 Percentile:31.31(Materials Science, Multidisciplinary)We report NMR studies on a single crystal of UCoGa, which has the same tetragonal HoCoGa (115) structure as the-wave high- superconductor PuCoGa. The spin-lattice relaxation rate () in UCoGa issmall comparing with those of other actinide 115 compounds. This fact is consistent with a semi-metallic nature of UCoGa suggested by de Haas-van Alphen effect measurements and band calculations. From comparison of at crystallografically different Ga and Co sites and the static susceptibility, an existence of two bands with rather different characters is revealed.
Kambe, Shinsaku; Sakai, Hironori; Tokunaga, Yo; Kato, Harukazu; Fujimoto, Tatsuya; Walstedt, R. E.*; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Aoki, Dai*; et al.
Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.176 - 181, 2007/03
performed NMR measurements in 5f-115 compounds with various ground states [UFeGa (Paramagnet), UPtGa, NpCoGa, NpFeGa (Antiferromagnet) and PuRhGa (Superconductor)], and evaluated the T-dependence of the local (actinide site) magnetic fluctuation energies (//c and c) in the paramagnetic states. An anisotropy in the magnetic fluctuations is observed in all compounds due to the strong LS coupling, in contrast to 3d-high Tc cuprates which have isotropic magnetic fluctuations at Cu sites. It is remarkable that the XY-type magnetic anisotropy is strong in PuRhGa comparing with the non-superconducting 5f-115 compounds. The fluctuation energy in PuRhGa is of the order of 10meV which is between of heavy fermion superconductors (1meV for 1K) and high cuprates (102meV for 100K). The relation between the magnetic fluctuation properties and the ground states will be discussed.
Kato, Harukazu*; Tsuruta, Takuya*; Nishioka, Takashi*; Matsumura, Masahiro*; Sakai, Hironori; Kambe, Shinsaku
Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.251 - 253, 2007/03
Cu NMR measurements have been carried out for CaCuRuO, which shows a heavy-fermion-like behavior although it posseses no f electron moment. The field-sweep spectrum observed can be understood as a powder pattern of a Cu nucleus affected by the quadrupole interaction with no axial symmetry. The quadrupole parameters and the Knight shift of Cu are evaluated.
Irizawa, Akinori*; Higashiya, Atsushi*; Kasai, Shuichi*; Sasabayashi, Takehisa*; Shigemoto, Akihiko*; Sekiyama, Akira*; Imada, Shin*; Suga, Shigemasa*; Sakai, Hironori; Ono, Hiroyuki*; et al.
Journal of the Physical Society of Japan, 75(9), p.094701_1 - 094701_5, 2006/09
Times Cited Count:6 Percentile:41.83(Physics, Multidisciplinary)Photoemission spectroscopy (PES) and O X-ray absorption spectroscopy (XAS) measurements have been performed for Cd Re O single crystals. Temperature variations of their spectra reveal that the phase transition at 120 K directly changes the band structure near the Fermi level compared with another transition near 200 K. The roles of the transitions are discussed in terms of the changes in the Re-O orbital hybridization.
Kambe, Shinsaku; Sakai, Hironori; Tokunaga, Yo; Fujimoto, Tatsuya; Kato, Harukazu; Walstedt, R. E.; Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Onuki, Yoshichika
Journal of the Physical Society of Japan, 75(Suppl.), p.127 - 129, 2006/08
Recently, new superconductors have been discovered in Pu-based HoCoGa(115) structure compounds: PuCoGa () and PuRhGa (). The discovery has stimulated a lot of interest in actinide compounds. We report NMR measurements on a high-quality single crystal sample of the non-superconducting U- and Np-based 115 compounds. In order to elucidate universal magnetic properties and the origin of superconductivity in the 115 families, spin-lattice relaxation and Knight shift measurements have been performed systematically in the non-superconducting 115 compounds. Comparison of dynamical properties with the superconducting Pu115 compounds will be presented.
Walstedt, R. E.*; Tokunaga, Yo; Kato, Harukazu*; Sakai, Hironori; Fujimoto, Tatsuya; Kambe, Shinsaku; Yasuoka, Hiroshi
Journal of the Physical Society of Japan, 75(Suppl.), p.77 - 81, 2006/08
In a brief recap of recent work on actinide NMR studies at JAERI, we review the direct observation of U NMR which has been carried out for both UO and USb, as well as the estimate of (T) for U which has been obtained from indirect (i.e., of Rh) NMR studies of the Pauli paramagnet URh. New data for 1/ vs. T for O in NpO are presented and analyzed. A sizeable fraction of the observed relaxation rate is strongly field-dependent, an effect attributed to a cross-relaxation process from the 100%-abundant, I = 5/2 Np nuclear spins. Analysis of this relaxation component leads to quantitative estimates of (40ns) and of anomalously enhanced values of the O-Np nuclear spin-spin coupling. These effects as well as future prospects for actinide NMR studies are discussed.
Tokunaga, Yo; Matsuda, Tatsuma; Sakai, Hironori; Kato, Harukazu*; Kambe, Shinsaku; Walstedt, R. E.; Haga, Yoshinori; Onuki, Yoshichika; Yasuoka, Hiroshi
Physical Review B, 71(4), p.045124_1 - 045124_5, 2005/01
Times Cited Count:10 Percentile:42.74(Materials Science, Multidisciplinary)P NMR measurements have been performed on the uranium-based ferromagnetic insulator UFeP with K. The field-orientation dependence of the hyperfine interaction has been measured using a single crystal, and the results compared with a point-dipolar field calculation assuming local moments at the U sites. We have also measured the field and temperature dependence of the nuclear spin-lattice relaxation rate () in several fields between 1.0 and 5.5 T at temperatures between 1.4 and 300 K. The results are discussed on the basis of a localized picture for the uranium 5f electrons.
Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Kitagawa, Kentaro*; Murakawa, Hiroshi*; Ishida, Kenji*; Ono, Hiroyuki*; Kato, Masaki*; Yoshimura, Kazuyoshi*; Walstedt, R. E.
Journal of the Physical Society of Japan, 73(11), p.2940 - 2943, 2004/11
Times Cited Count:8 Percentile:48.29(Physics, Multidisciplinary)Cd NMR measurements have been performed in the superconducting (SC) state of the pyrochlore CdReO at T 1 K, and in a field of less than 3 kOe below . The upper critical field at 0.1 K has been determined to be 4 kOe from in situ measurements of the ac susceptibility. A reduction of the Knight shift in the SC state is confirmed. The present results provide strong evidence that this compound has a singlet SC pairing symmetry.
Kato, Harukazu*; Sakai, Hironori; Ikushima, Kenji*; Kambe, Shinsaku; Tokunaga, Yo; Aoki, Dai*; Haga, Yoshinori; Onuki, Yoshichika; Yasuoka, Hiroshi; Walstedt, R. E.
Journal of the Physical Society of Japan, 73(8), p.2085 - 2088, 2004/08
Times Cited Count:12 Percentile:57.62(Physics, Multidisciplinary)Diret AFNMR studies of U, Sb and Sb nuclear spins have been carried out in the antiferromagnetic state of USb. The central U transition have been found as 217.2MHz based on several tests. The U hyperfine coupling constant is estimated as 147T/mB. This is the first observation of U NMR in a metallic compound.
Sakai, Hironori; Kato, Harukazu; Tokunaga, Yo; Kambe, Shinsaku; Walstedt, R. E.; Nakamura, Akio; Tateiwa, Naoyuki*; Kobayashi, Tatsuo*
Journal of Magnetism and Magnetic Materials, 272-276(Suppl.), p.e413 - e414, 2004/05
Times Cited Count:2 Percentile:13.76(Materials Science, Multidisciplinary)The d.c. magnetization of insulating UO under high pressure up to about 1 GPa has been measured using a piston-cylinder cell. Pressure-induced weak ferromagnetism was found to appear at low pressure (about 0.2 GPa). Both the remanent magnetization and the coercive force increase as pressure increases. This weak ferromagnetism may come from spin canting or from uncompensated moments around grain boundaries.
Kato, Harukazu; Sakai, Hironori; Kambe, Shinsaku; Walstedt, R. E.; Tokiwa, Yoshifumi; Onuki, Yoshichika
Acta Physica Polonica B, 34(2), p.1063 - 1066, 2003/09
We performed Ga-NMR/NQR studies for UPtGa, which is a 5-itinerant antiferromagnets with Neel temperature = 26 K and an electronic specific coefficient = 57 mJ/mol K. From the NMR spectrum in the paramagnetic temperature region, the hyperfine coupling constants in the paramagnetic state have been evaluated. The magnitude of the transferred field has been evaluated from the zero-applied-field spectrum, yielding a value for the hyperfine coupling constant in the antiferromagnetic state. The estimated value of is an order of magnitude larger than that of . This implies the existence of a long-ranged hyperfine interaction path. The mechanism of the hyperfine interaction will be discussed in terms of RKKY interactions.
Kato, Harukazu; Sakai, Hironori; Tokunaga, Yo; Tokiwa, Yoshifumi; Ikeda, Shugo; Onuki, Yoshichika; Kambe, Shinsaku; Walstedt, R. E.
Journal of the Physical Society of Japan, 72(9), p.2357 - 2363, 2003/09
Times Cited Count:17 Percentile:66.96(Physics, Multidisciplinary)Ga and Pt NMR measurements have been carried out for two isomorphs compounds, UPtGa and UNiGa, which indicate different magnetic structures below T. Knight shift K measurements in the paramagnetic region are reported here. Transferred hyperfine coupling constants at Ga and Pt sites are determined. The temperature independent part K of K, which probes the conduction electron polarization at the ligand site, has successfully evaluated. An nearly identical conduction electron structure in the paramagnetic region is suggested for the both compounds. The origin of the different magnetic structure is discussed.
Sakai, Hironori; Kato, Harukazu; Tokunaga, Yo; Kambe, Shinsaku; Walstedt, R. E.; Nakamura, Akio; Tateiwa, Naoyuki*; Kobayashi, Tatsuo*
Journal of Physics; Condensed Matter, 15(28), p.S2035 - S2037, 2003/07
Times Cited Count:3 Percentile:21.33(Physics, Condensed Matter)The cubic-fluorite type uranium dioxide UO is an ionically bounded insulator with localized magnetic moments of U (5) ions. Under atmospheric pressure, UO exhibits a first order antiferromagnetic transition at =30.8 K accompanied by a small lattice distortion. In order to clarify the interrelation between QQ and exchange interactions in this system, we performed d.c. magnetization measurement under high pressure up to about 1 GPa by a piston-cylinder-type cramped cell. From the d.c. magnetization measurements under high pressure ( 0.1 GPa), it is found that UO shows a weak-ferromagnetic-like transition at 30 K, where the transition temperature is almost independent of external pressure up to 1 GPa. The ferromagnetic component per uranium atom is very small (), although its component is dependent of pressure. This small ferromagnetic component may come from a canted antiferromagnetic ordering.
Kato, Harukazu; Sakai, Hironori; Tokunaga, Yo; Tokiwa, Yoshifumi; Ikeda, Shugo; Onuki, Yoshichika; Kambe, Shinsaku; Walstedt, R. E.
Journal of Physics; Condensed Matter, 15(28), p.S2001 - S2005, 2003/07
Times Cited Count:4 Percentile:26.93(Physics, Condensed Matter)UPtGa and UNiGa are 5-itinerant antiferromagnets with Nel temperature = 26 K (Pt), 86 K (Ni). Remarkably, although the two compounds show almost identical Fermi surface properties in the paramagnetic state, recent neutron scattering experiments reveal that UPtGa and UNiGa are quite different in magnetic structure below . In the microscopic viewpoint, we have carried out Ga NMR/NQR measurements for the both coumpounds. We have suceeded in separating the temperature independent term and the Curie-like-temperature-dependent term of the Knight shift . This should be a good starting point in considering the magnetism of this system.