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Kasamatsu, Yoshitaka*; Toyoshima, Atsushi; Tome, Hayato*; Tsukada, Kazuaki; Asai, Masato; Haba, Hiromitsu*; Nagame, Yuichiro
Journal of Nuclear and Radiochemical Sciences (Internet), 13(1), p.9 - 12, 2013/06
Adsorption behavior of the group-5 elements, Nb and
Ta, on cation-exchange resin was studied in mixed solution of HF and HNO
as a model experiment of their heavier homologue, element 105 (dubnium, Db). Chemical reactions of these elements in the cation exchange rapidly reached the equilibrium. It was found that distribution coefficients of Nb and Ta decrease with increasing the fluoride ion concentration in the studied range of 10
- 10
M. Clear difference between Nb and Ta was observed in the variations of the distribution coefficients against the fluoride ion concentration. This would originate from their different chemical species of fluoride complexes. We propose the cation-exchange experiment of Db based on the present experimental results to understand its fluoride complex formation.
Toyoshima, Atsushi; Kasamatsu, Yoshitaka*; Tsukada, Kazuaki; Asai, Masato; Ishii, Yasuo; Tome, Hayato*; Nishinaka, Ichiro; Sato, Tetsuya; Nagame, Yuichiro; Schdel, M.; et al.
Journal of Nuclear and Radiochemical Sciences, 11(1), p.7 - 11, 2010/06
The extraction behavior of rutherfordium (Rf) into trioctylphosphine oxide (TOPO) from 2.0 - 7.0 M HCl solution was studied together with that of the homologues Zr and Hf. The extracted yields of Rf, Zr, and Hf increased with an increase of HCl concentration, and the sequence of their extraction was Zr Hf
Rf. It is suggested that the stability of the RfCl
2(TOPO) complex is lower than that of the corresponding species of the homologues.
Kasamatsu, Yoshitaka*; Toyoshima, Atsushi; Asai, Masato; Tsukada, Kazuaki; Li, Z.; Ishii, Yasuo; Tome, Hayato*; Sato, Tetsuya; Kikuchi, Takahiro; Nishinaka, Ichiro; et al.
Chemistry Letters, 38(11), p.1084 - 1085, 2009/10
Times Cited Count:14 Percentile:49.21(Chemistry, Multidisciplinary)We report on the characteristic anion-exchange behavior of the superheavy element dubnium (Db) with atomic number Z = 105 in HF/HNO solution at the fluoride ion concentration [F
] = 0.003 M. The result clearly demonstrates that the fluoro complex formation of Db is significantly different from that of the group-5 homologue Ta in the 6th period of the periodic table while the behavior of Db is similar to that of the lighter homologue Nb in the 5th period.
Toyoshima, Atsushi; Kasamatsu, Yoshitaka*; Tsukada, Kazuaki; Asai, Masato; Kitatsuji, Yoshihiro; Ishii, Yasuo; Tome, Hayato; Nishinaka, Ichiro; Haba, Hiromitsu*; Oe, Kazuhiro*; et al.
Journal of the American Chemical Society, 131(26), p.9180 - 9181, 2009/07
Times Cited Count:13 Percentile:45.83(Chemistry, Multidisciplinary)We report here on the successful oxidation of element 102, nobelium (No), on an atom-at-a-time scale in 0.1 M -hydroxyisobutyric acid (
-HIB) solution using newly developed flow electrolytic column chromatography. It is found that the most stable No
is oxidized to No
within 3 min and that the oxidized No complex with
-HIB holds the trivalent state in the column above the applied potential of 1.0 V.
Kasamatsu, Yoshitaka; Toyoshima, Atsushi; Haba, Hiromitsu*; Tome, Hayato*; Tsukada, Kazuaki; Akiyama, Kazuhiko*; Yoshimura, Takashi*; Nagame, Yuichiro
Journal of Radioanalytical and Nuclear Chemistry, 279(2), p.371 - 376, 2009/02
Times Cited Count:11 Percentile:60.18(Chemistry, Analytical)Anion-exchange behavior of the group-5 elements Nb and Ta, and their pseudo homologue Pa in HF and HF/HNO solutions was investigated by a batch method to find suitable conditions for the anion-exchange experiment of element 105 (Dubnium, Db). We determined distribution coefficients of those elements on the anion-exchange resin as a function of the F
and NO
concentrations. Clearly different anion-exchange behavior was observed among these elements. Based on the results, we discuss the fluoro-complex formation of each element and suggest experimental conditions for the study of fluoride complexation of Db.
Ishii, Tetsuro; Makii, Hiroyuki*; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shigematsu, Soichiro*; Kaneko, Junichi*; Shizuma, Toshiyuki; et al.
Physical Review C, 78(5), p.054309_1 - 054309_11, 2008/11
Times Cited Count:14 Percentile:65.27(Physics, Nuclear)Ishii, Tetsuro; Makii, Hiroyuki; Asai, Masato; Koura, Hiroyuki; Shigematsu, Soichiro*; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; et al.
Nuclear Physics A, 805(1-4), p.257 - 259, 2008/06
no abstracts in English
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:55.32(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.
Makii, Hiroyuki; Ishii, Tetsuro; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Kaneko, Junichi*; Tome, Hayato*; Ichikawa, Shinichi; et al.
Physical Review C, 76(6), p.061301_1 - 061301_5, 2007/12
Times Cited Count:28 Percentile:83.62(Physics, Nuclear)We have measured deexcitation rays for the first time in the neutron-rich nuclei of
Pu
and
Pu
produced by the (
O,
O) and the (
O,
O) reactions, respectively. The ground-state band of
Pu was established up to 12
states. The systematics of the moments of inertia of
Pu isotopes suggests that the
deformed subshell closure disappears in these isotopes. The measurements of deexcitation
rays in
Pu shows a small energy spacing between neutron orbitals at
, which explans the disappearance of the subshell closure.
Kasamatsu, Yoshitaka; Toyoshima, Atsushi; Tome, Hayato; Tsukada, Kazuaki; Haba, Hiromitsu*; Nagame, Yuichiro
Journal of Nuclear and Radiochemical Sciences, 8(2), p.69 - 72, 2007/10
We investigated anion-exchange behavior of Nb, Ta and Pa in HF/HNO media to find suitable experimental conditions for the study of the Db fluoride complex formation. We measured Kd values of Nb, Ta and Pa on strong basic anion exchangers in the wide range of the fluoride ion concentration, 1
10
2
10
M, in order to in detail investigate anionic fluoride complex formation of those elements. We have used tracer concentrations of isotopes of
Nb,
Ta and
Pa in the experiments. Variation of the Kd values as a function of [NO
] was also studied. As a result, we observed an apparent difference in the adsorption behavior of the homologues. Based on these results together with the measurement of the equilibrium time, we propose rapid online experimental condition for the study of Db fluoride.
Ishii, Tetsuro; Shigematsu, Soichiro*; Makii, Hiroyuki; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; Kaneko, Junichi*; et al.
Physics of Atomic Nuclei, 70(8), p.1457 - 1461, 2007/08
Times Cited Count:9 Percentile:56.75(Physics, Nuclear)We have measured deexcitation rays in the neutron-rich nuclei of
U,
Pu and
Cm. These nuclei were produced by the (
O,
O) two-neutron transfer reactions with a 200, 162 and 162 MeV
O beams and a
U,
Pu and
Cm targets, respectively, using the tandem accelerator at Tokai, Japan. The
rays in residual nuclei were measured by taking coincidence with scattering particles using Si
-
detectors. We have identified
rays in
U,
Pu and
Cm by selecting the kinetic energies of
O particles which correspond to the excitation energies in these nuclei below their neutron separation energies. The ground-state bands of
U,
Pu and
Cm were established up to 12
states and the
octupole band of
U was established up to 9
state. Because the deformations of these nuclei are well developed, the moments of inertia reflect the pairing gap, which is expected to be smaller, resulting in a larger moment of inertia, at the deformed shell closure. We have found that the moment of inertia of the ground-state band of
Cm
is considerably larger than that of
Cm
. This fact supports the existence of the deformed subshell closure at
in Cm isotopes. On the other hand, the moment of inertia of
Pu
was found to be smaller than that of
Pu
, which suggests that the deformed subshell closure at
weakens or disappears in Pu isotopes. These results are consistent with the prediction by a cranking model calculation.
Ishii, Tetsuro; Makii, Hiroyuki; Asai, Masato; Koura, Hiroyuki; Shigematsu, Soichiro*; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Kaneko, Junichi*; et al.
Physical Review C, 76(1), p.011303_1 - 011303_5, 2007/07
Times Cited Count:14 Percentile:68.08(Physics, Nuclear)The ground-state bands of the neutron-rich Th and
U nuclei were established up to spin 10 and 8, respectively, by in-beam
-ray spectroscopy using the (
O,
Ne) two-proton pickup reaction with a
U and a
Pu target. Deexcitation
rays in
Th and
U were identified by selecting the kinetic energies of
Ne using Si
-
detectors. The excitation energies of the first 2
states in U and Pu isotopes have local minima at
, suggesting the possibility that nuclei with
have a spherical shell closure of
. Calculation using the Koura-Yamada single-particle potential gives an energy gap of 1.8 MeV at
for
U.
Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Toyoshima, Atsushi; Ishii, Yasuo; Tome, Hayato; Sato, Tetsuya; Nishinaka, Ichiro; Ichikawa, Takatoshi; Ichikawa, Shinichi; et al.
Radiochimica Acta, 95(1), p.1 - 6, 2007/01
Times Cited Count:15 Percentile:70.66(Chemistry, Inorganic & Nuclear)no abstracts in English
Ishii, Tetsuro; Shigematsu, Soichiro; Makii, Hiroyuki; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; Kaneko, Junichi*; et al.
Journal of the Physical Society of Japan, 75(4), p.043201_1 - 043201_4, 2006/04
Times Cited Count:19 Percentile:68.59(Physics, Multidisciplinary)The ground-state band of the neutron-rich transuranium nucleus Cm was established up to spin 12 by in-beam
-ray spectroscopy using the two-neutron-transfer reaction with a
Cm target and a 162 MeV
O beam. Deexcitation
rays in
Cm were identified by selecting the kinetic energies of
O particles with Si
-
detectors. The moment of inertia of
Cm
is considerably smaller than that of
Cm
, which supports the existence of the deformed subshell closure at
in Cm isotopes.
Ishii, Tetsuro; Shigematsu, Soichiro; Makii, Hiroyuki; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Shizuma, Toshiyuki; Kaneko, Junichi*; et al.
no journal, ,
no abstracts in English
Tsukada, Kazuaki; Toyoshima, Atsushi; Haba, Hiromitsu*; Asai, Masato; Akiyama, Kazuhiko*; Ishii, Yasuo; Tome, Hayato*; Nishinaka, Ichiro; Sato, Tetsuya; Ichikawa, Takatoshi; et al.
no journal, ,
no abstracts in English
Toyoshima, Atsushi; Haba, Hiromitsu*; Tsukada, Kazuaki; Asai, Masato; Akiyama, Kazuhiko*; Ishii, Yasuo; Tome, Hayato*; Nishinaka, Ichiro; Sato, Tetsuya; Ichikawa, Takatoshi; et al.
no journal, ,
no abstracts in English
Makii, Hiroyuki; Ishii, Tetsuro; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Kaneko, Junichi*; Tome, Hayato; Ichikawa, Shinichi; et al.
no journal, ,
no abstracts in English
Tsukada, Kazuaki; Toyoshima, Atsushi; Haba, Hiromitsu*; Asai, Masato; Akiyama, Kazuhiko*; Ishii, Yasuo; Tome, Hayato; Nishinaka, Ichiro; Sato, Tetsuya; Ichikawa, Shinichi; et al.
no journal, ,
no abstracts in English
Kasamatsu, Yoshitaka; Toyoshima, Atsushi; Tome, Hayato; Tsukada, Kazuaki; Haba, Hiromitsu*; Nagame, Yuichiro
no journal, ,
no abstracts in English