Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Nakahara, Masaumi; Watanabe, So; Aihara, Haruka; Takahatake, Yoko; Arai, Yoichi; Ogi, Hiromichi*; Nakamura, Masahiro; Shibata, Atsuhiro; Nomura, Kazunori
Proceedings of International Conference on Nuclear Fuel Cycle; Sustainable Energy Beyond the Pandemic (GLOBAL 2022) (Internet), 4 Pages, 2022/07
Various radioactive wastes have been generated from Chemical Processing Facility for basic research on advanced reactor fuel reprocessing, radioactive waste disposal, and nuclear fuel cycle technology. Many types of reagents have been used for the experiments, and some troublesome materials were produced in the course of experiments. The radioactive liquid wastes were treated for stable and safe storage using decomposition, solvent extraction, precipitation, and solidification methods. In this study, current status of harmless treatment for the radioactive liquid wastes would be reported.
Nakahara, Masaumi; Watanabe, So; Ogi, Hiromichi*; Arai, Yoichi; Aihara, Haruka; Motoyama, Risa; Shibata, Atsuhiro; Nomura, Kazunori; Kajinami, Akihiko*
Proceedings of International Nuclear Fuel Cycle Conference / Light Water Reactor Fuel Performance Conference (Global/Top Fuel 2019) (USB Flash Drive), p.66 - 70, 2019/09
A wide variety of hazardous and radioactive liquid waste has generated derived from an advanced aqueous separation experiments in the Chemical Processing Facility. Therefore, they should be stabilized for the safety handling and management. In this study, we report a precipitation or an oxidation for hazardous materials, a solvent extraction for recovery of nuclear materials, and a concentration of solution by a freeze-drying method.
Nakahara, Masaumi; Watanabe, So; Ogi, Hiromichi*; Shibata, Atsuhiro; Nomura, Kazunori
International Journal of Nuclear and Quantum Engineering (Internet), 13(4), p.191 - 194, 2019/04
High level radioactive solid waste is reduced the volume or stabilized in the Chemical Processing Facility in the Japan Atomic Energy Agency. A plastic product is molten with a heating mantle and reduced the volume. A non-flammable such as metal is cut with a band saw machine for reducing the volume. A used adsorbent in the extraction chromatograph process was heated with an electric furnace using non-radioactive materials, and the experimental result suggests that organic materials in the used adsorbent were decomposed stably.
Nomura, Kazunori; Ogi, Hiromichi*; Nakahara, Masaumi; Watanabe, So; Shibata, Atsuhiro
International Journal of Nuclear and Quantum Engineering (Internet), 13(5), p.209 - 212, 2019/00
Nagame, Yuichiro; Nakahara, Hiromichi*
Radiochimica Acta, 100(8-9), p.605 - 614, 2012/08
Times Cited Count：6 Percentile：44.59(Chemistry, Inorganic & Nuclear)Nagame, Yuichiro; Hirata, Masaru; Nakahara, Hiromichi*
Handbook of Nuclear Chemistry, p.817 - 875, 2011/02
UNishinaka, Ichiro; Tanikawa, Masashi*; Nagame, Yuichiro; Nakahara, Hiromichi*
European Physical Journal A, 47(1), p.1 - 8, 2011/01
Times Cited Count：18 Percentile：72.78(Physics, Nuclear)The most probable charges of secondary fragments in the 11.5 MeV proton-induced fission of U were determined from the mass yields measured by the double time-of-flight method and the fractional cumulative and independent yields measured radiochemically and reported in literature. The nuclear-charge polarization of primary fragments at scission was obtained by correcting the secondary fragment mass for neutron evaporation. The results show that the nuclear-charge polarization is determined by the minimum potential energy of nuclei at scission and that it is nearly independent not only of mass and excitation energy but also of the neutron-to-proton ratio of the fissioning nucleus.
Furuta, Etsuko*; Nakahara, Hiromichi*; Hatsukawa, Yuichi; Matsue, Hideaki; Sakane, Hitoshi*
Journal of Radioanalytical and Nuclear Chemistry, 278(3), p.553 - 557, 2008/12
Times Cited Count：6 Percentile：40.75(Chemistry, Analytical)In Japan, cosmetics which declared hormesis effect are available through Internet. The existence of a daughter nuclides of Th and U series, however, were observed by measurements of the 
rays with a high purity Ge detector. In this study, in order to clarify the contents of trace elements, the hormesis cosmetics including radiation sources were analyzed using instrumental neutron activation analysis method (INAA), prompt activation analysis (PGAA) and neutron activation analysis with multiple ray detection (NAAMG). In the conference, we will report the results of analysis data which including heavy metallic and actinide elements. Furthermore, we will evaluate a possibility of uptake of heavy metal elements and radiation sources, and will discuss the influence of them to human body.
Ishii, Yasuo; Toyoshima, Atsushi; Tsukada, Kazuaki; Asai, Masato; Tome, Hayato; Nishinaka, Ichiro; Nagame, Yuichiro; Miyashita, Sunao*; Mori, Tomotaka*; Suganuma, Hideo*; et al.
Chemistry Letters, 37(3), p.288 - 289, 2008/03
Times Cited Count：20 Percentile：55.49(Chemistry, Multidisciplinary)We have investigated cation-exchange behavior of Rf together with the lighter homologues of the group-4 elements Zr and Hf, and the tetravalent pseudo-homologue Th, in HF/HNO
solution using Automated Ion exchange separation apparatus coupled with the Detection system for Alpha spectroscopy (AIDA). The 
values of Zr, Hf, Th and Rf in HF/0.1 M HNO were decreased with increasing the concentration of the fluoride ion [F
], indicating the formation of the fluoride complexes. The sequence of the fluoride complexation strength is Zr 
Hf 
Rf Th.
solutionsToyoshima, Atsushi; Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Akiyama, Kazuhiko*; Goto, Shinichi*; Ishii, Yasuo; Nishinaka, Ichiro; Sato, Tetsuya; Nagame, Yuichiro; et al.
Radiochimica Acta, 96(3), p.125 - 134, 2008/03
Times Cited Count：28 Percentile：85.57(Chemistry, Inorganic & Nuclear)Formation of an anionic fluoride-complex of element 104, rutherfordium (Rf) produced in the 
Cm(
O,5n)
Rf reaction was studied by an anion-exchange method based on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF
]
, was formed in the studied fluoride ion concentrations of 0.0005 - 0.013 M. Formation of [RfF] was significantly different from that of the homologues Zr and Hf, [ZrF] and [HfF]; the evaluated formation constant of [RfF] is at least one-order of magnitude smaller than those of [ZrF] and [HfF].
ThNishinaka, Ichiro; Nakahara, Hiromichi*; Nagame, Yuichiro
European Physical Journal A, 33(2), p.231 - 236, 2007/08
Times Cited Count：4 Percentile：36.03(Physics, Nuclear)The most probable charges of secondary fragments, produced after neutron evaporation from primary fragments, have been evaluated using fractional cumulative and mass yields in the 12 MeV proton-induced fission of Th. The nuclear charge polarization of primary fragments at scission has been obtained by correcting the most probable charge of secondary fragments for neutron evaporation. The fragment mass dependence of the nuclear charge polarization at scission shows good agreement with that for thermal neutron-induced fission of 
U, indicating that the nuclear charge polarization is nearly insensitive to mass and excitation energy of the fissioning nucleus for asymmetric fission in the actinide region.
Nagame, Yuichiro; Nishinaka, Ichiro; Zhao, Y. L.*; Nakahara, Hiromichi*
Romanian Reports in Physics, 59(2), p.545 - 558, 2007/00
Existence of two kinds of scission configurations associated with symmetric and asymmetric fission modes is pointed out in the fission of actinides: elongated and compact configurations. Each scission property is discussed in terms of shape elongation evaluated from fragment total kinetic energy (TKE). Fragment deformation at scission is also discussed based on neutron multiplicity measurements. From the systematic study of the scission properties in a wide range of actinides, the bimodal fission observed in the spontaneous fission (SF) of the heavy actinides would be interpreted as the result of the presence of the two fission paths; the ordinary asymmetric fission path is still exiting while the symmetric one is bifurcated by strongly shell-influenced effects.
Nagame, Yuichiro; Nakahara, Hiromichi*
Nihon Butsuri Gakkai-Shi, 60(9), p.707 - 709, 2005/09
no abstracts in English
Am and its EC-decay daughter 
PuAsai, Masato; Sakama, Minoru*; Tsukada, Kazuaki; Ichikawa, Shinichi; Haba, Hiromitsu*; Nishinaka, Ichiro; Nagame, Yuichiro; Goto, Shinichi*; Kojima, Yasuaki*; Oura, Yasuji*; et al.
European Physical Journal A, 23(3), p.395 - 400, 2005/02
Times Cited Count：14 Percentile：68.26(Physics, Nuclear)The EC decay of Am has been studied through -ray spectroscopy. Two EC-decaying states have been found in Am with half-lives of 3.6 min and 2.9 min. In Pu, we have found the 
octupole band and two-quasiparticle states one of which is a 
isomer with a 1.2 
s half-life. The EC transitions from Am to the two-quasiparticle states in Pu show small 
values of 4.8--5.3, which allowed us to assign proton-neutron configurations of Am and the two-quasiparticle states.
Nagame, Yuichiro; Tsukada, Kazuaki; Asai, Masato; Toyoshima, Atsushi; Akiyama, Kazuhiko; Ishii, Yasuo; Sato, Tetsuya; Hirata, Masaru; Nishinaka, Ichiro; Ichikawa, Shinichi; et al.
Radiochimica Acta, 93(9-10), p.519 - 526, 2005/00
Times Cited Count：29 Percentile：86.8(Chemistry, Inorganic & Nuclear)no abstracts in English
decays of AmAsai, Masato; Sakama, Minoru*; Tsukada, Kazuaki; Ichikawa, Shinichi; Haba, Hiromitsu*; Nishinaka, Ichiro; Nagame, Yuichiro; Goto, Shinichi*; Kojima, Yasuaki*; Oura, Yasuji*; et al.
European Physical Journal A, 22(3), p.411 - 416, 2004/12
Times Cited Count：9 Percentile：51.57(Physics, Nuclear)EC and decays of Am have been studied by means of -ray spectroscopy. Excited states in Pu have been established for the first time, and tentative spin-parity and Nilsson assignments were given to these levels. The ground state of Am was evaluated to be the ![$$pi 5/2^{-}[523]$$](/search/images/EROHA0JAGUXTEXT1FV4VWNJSGNOSI.gif)
state from the experimental results. It was found that the state in 
Np is located at 
15~keV, which allowed us to determine the 
value of Am as 6569
~keV, in combination with the measured -particle energy.
Nishinaka, Ichiro; Nagame, Yuichiro; Ikezoe, Hiroshi; Tanikawa, Masashi*; Zhao, Y. L.*; Sueki, Keisuke*; Nakahara, Hiromichi
Physical Review C, 70(1), p.014609_1 - 014609_10, 2004/07
Times Cited Count：16 Percentile：67.33(Physics, Nuclear)no abstracts in English
Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Toyoshima, Atsushi; Akiyama, Kazuhiko; Nishinaka, Ichiro; Hirata, Masaru; Yaita, Tsuyoshi; Ichikawa, Shinichi; Nagame, Yuichiro; et al.
Journal of the American Chemical Society, 126(16), p.5219 - 5224, 2004/04
Times Cited Count：43 Percentile：72.74(Chemistry, Multidisciplinary)Fluoride complexation of element 104, rutherfordium (Rf), produced in the Cm(O,5n)Rf reaction has been studied by anion-exchange chromatography on an atom-at-a-time scale. The anion-exchangechromatographic behavior of Rf was investigated in 1.9-13.9 M hydrofluoric acid together with those of the group-4 elements Zr and Hf produced in the O-induced reactions on Ge and Gd targets, respectively. It was found that the adsorption behavior of Rf on anion-exchange resin is quite different from those of Zr and Hf, suggesting the influence of relativistic effect on the fluoride complexation of Rf.
Nagame, Yuichiro; Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Toyoshima, Atsushi; Goto, Shinichi*; Akiyama, Kazuhiko; Kaneko, Tetsuya; Sakama, Minoru*; Hirata, Masaru; et al.
Nuclear Physics A, 734, p.124 - 135, 2004/04
Times Cited Count：11 Percentile：57.19(Physics, Nuclear)no abstracts in English
-decays of neutron-deficient americium isotopesSakama, Minoru*; Asai, Masato; Tsukada, Kazuaki; Ichikawa, Shinichi; Nishinaka, Ichiro; Nagame, Yuichiro; Haba, Hiromitsu*; Goto, Shinichi*; Shibata, Michihiro*; Kawade, Kiyoshi*; et al.
Physical Review C, 69(1), p.014308_1 - 014308_11, 2004/01
Times Cited Count：21 Percentile：74.01(Physics, Nuclear)no abstracts in English
