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Kawasaki, Riku*; Sasaki, Yoshihiro*; Nishimura, Tomoki*; Katagiri, Kiyofumi*; Morita, Keiichi*; Sekine, Yurina; Sawada, Shinichi*; Mukai, Sadaatsu*; Akiyoshi, Kazunari*
Advanced Healthcare Materials, 10(9), p.2001988_1 - 2001988_8, 2021/05
Times Cited Count：8 Percentile：60(Engineering, Biomedical)Systems for "protein transduction", the intracellular delivery of functional proteins, are needed to address the deliverability challenges of protein therapy, but protein transfer in vivo remains difficult. In this study, we have developed a magnetically induced in vivo protein transfection system using a magnetic nanogel chaperone (MC) composed of iron oxide nanoparticles and polysaccharide nanogels. Experiments using an oral cancer model have shown that this MC system is useful for cancer treatment.
Fujihara, Masayoshi*; Morita, Katsuhiro*; Mole, R.*; Mitsuda, Setsuo*; Toyama, Takami*; Yano, Shinichiro*; Yu, D.*; Sota, Shigetoshi*; Kuwai, Tomohiko*; Koda, Akihiro*; et al.
Nature Communications (Internet), 11, p.3429_1 - 3429_7, 2020/07
Times Cited Count：37 Percentile：90.63(Multidisciplinary Sciences)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：18 Percentile：74.47(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.
Sasaki, Yuji; Morita, Keisuke; Ito, Keisuke; Suzuki, Shinichi; Shiwaku, Hideaki; Takahashi, Yuya*; Kaneko, Masaaki*; Omori, Takashi*; Asano, Kazuhito*
Proceedings of International Nuclear Fuel Cycle Conference (GLOBAL 2017) (USB Flash Drive), 4 Pages, 2017/09
no abstracts in English
Sasaki, Yuji; Morita, Keisuke; Suzuki, Shinichi; Shiwaku, Hideaki; Ito, Keisuke; Takahashi, Yuya*; Kaneko, Masaaki*
Solvent Extraction Research and Development, Japan, 24(2), p.113 - 122, 2017/06
The solvent extraction of Se, Zr, Pd, and Cs from nitric acid into 1-octanol (OC) and dodecane has been performed. These elements include long-lived radionuclides in spent nuclear fuels, so a simple separation method is indispensable for the development of the treatment of high-level liquid radioactive waste. It was found that Se can be extracted using phenylenediamine, Zr can be extracted using tetraoctyl diglycolamide and di-2-ethylhexyl phosphoric acid, and Pd can be extracted using (methylimino)bis(dioctylacetamide) and hexaoctylnitrilotriacetamide. These elements can be recovered in over 90% yield by these extractants from nitric acid into OC. A distribution ratio of Cs of greater than 1 can be obtained using di-t-butyldibenzo-18-crown-6. It is clear that 90% recovery of Cs can be achieved using an extraction solvent with ten times the volume of the aqueous phase.
Kaji, Daiya*; Morimoto, Koji*; Wakabayashi, Yasuo*; Takeyama, Mirei*; Yamaki, Sayaka*; Tanaka, Kengo*; Haba, Hiromitsu*; Huang, M.*; Murakami, Masashi*; Kanaya, Jumpei*; et al.
JPS Conference Proceedings (Internet), 6, p.030107_1 - 030107_4, 2015/06
Performance of the new gas-filled recoil ion separator GARIS-II was investigated using asymmetric 
Ne-induced fusion reactions. The use of He-H
mixture gas for the gas-filled magnet significantly reduced background scattered particles detected at the focal-plane Si detector, and increased a transmission of the asymmetric reaction products. A target-identification system was newly installed for efficient measurements of excitation functions without changing beam energy nor target.
Cm + 
O reactionMurakami, Masashi*; Goto, Shinichi*; Murayama, Hirofumi*; Kojima, Takayuki*; Kudo, Hisaaki*; Kaji, Daiya*; Morimoto, Koji*; Haba, Hiromitsu*; Kudo, Yuki*; Sumita, Takayuki*; et al.
Physical Review C, 88(2), p.024618_1 - 024618_8, 2013/08
Times Cited Count：15 Percentile：66.57(Physics, Nuclear)Production cross sections of Rf isotopes in the Cm + O reaction were measured at the beam energy range of 88.2 to 101.3 MeV by use of a gas-filled recoil ion separator. The excitation functions of 
Rf, 
Rf, and 
Rf were obtained together with those of spontaneously fissioning nuclides which have few-second half-lives and have been assigned to 
Rf and a longer-lived state of Rf. The excitation function of few-second spontaneously fissioning nuclide exhibited the maximum cross section at the O beam energy of 94.8 MeV. The shape of the excitation function was almost the same as that of Rf, whereas it was quite different from those of Rf and Rf. A few-second spontaneously fissioning nuclide previously reported as Rf and Rf observed inCm + O reaction was identified as Rf.
113 of the 113th elementMorita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Haba, Hiromitsu*; Ozeki, Kazutaka*; Kudo, Yuki*; Sumita, Takayuki*; Wakabayashi, Yasuo*; Yoneda, Akira*; Tanaka, Kengo*; et al.
Journal of the Physical Society of Japan, 81(10), p.103201_1 - 103201_4, 2012/10
Times Cited Count：167 Percentile：97.27(Physics, Multidisciplinary)An isotope of the 113th element, 113, was produced in a nuclear reaction with a 
Zn beam on a 
Bi target. We observed six consecutive 
decays following the implantation of a heavy particle in nearly the same position in the semiconductor detector, in extremely low background condition. The fifth and sixth decays are fully consistent with the sequential decays of Db and 
Lr both in decay energies and decay times. This indicates that the present decay chain consisted of 113, 
Rg (Z = 111), 
Mt (Z = 109), 
Bh (Z = 107), Db (Z = 105), and Lr (Z = 103) with firm connections. This result, together with previously reported results from 2004 and 2007, conclusively leads the unambiguous production and identification of the isotope 113, of the 113th element.
Koyama, Shinichi; Suzuki, Tatsuya*; Ozawa, Masaki*; Kurosawa, Kiyoko*; Fujita, Reiko*; Mimura, Hitoshi*; Okada, Ken*; Morita, Yasuji; Fujii, Yasuhiko*
Procedia Chemistry, 7, p.222 - 230, 2012/00
Times Cited Count：2 Percentile：71.08(Chemistry, Analytical)Adv.-ORIENT cycle strategy has been proposed as a basic concept for trinitarian research on separation, transmutation and utilization of nuclides and elements based on FBR fuel cycle. Validation of principal separation method and related safety research were performed from 2006 through 2011 as Phase I program. First, more than 90% of Cs could be recovered from the actual spent fuel [IXC(I) step]. The next is the adsorption of the platinum group metals (PGM), lanthanides, Am and Cm were separated by using a tertiary pyridine-type resin (TPR) as ion exchange steps [IXC(II, III, IV) steps]. The separated PGM metals will be supplied to the electrochemical extraction [CEE step]. As experiment for safety issues, Hastelloy-B at RT and Ta at 90
C were confirmed their anti-corrosive in highly concentrated HCl media. Thermo-chemical stability for TPR was verified. Issues to be solved for next phase based on the final results of phase I program.
Minato, Kazuo; Morita, Yasuji; Tsujimoto, Kazufumi; Koyama, Shinichi; Kurata, Masaki*; Inoue, Tadashi*; Ikeda, Kazumi*
Proceedings of 11th OECD/NEA Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation (Internet), p.341 - 349, 2012/00
In order to provide a quantitative assessment for the maturity of the partitioning and transmutation technology relative to its full-scale deployment, a technology readiness level (TRL) process was used. The definitions of TRL used in this study were based on those used in the Global Nuclear Energy Partnership (GNEP). The TRL was evaluated and the technology pathway was discussed for the systems of FBR and ADS for the minor actinides (MA) transmutation, MA partitioning processes, and MA-bearing fuels. Through the evaluation, it was recognized that hard requirements to be satisfied were present at TRL 5 for each technology development. The introduction of lab-scale tests with actual spent fuel for MA partitioning process and with actual separated materials for MA-bearing fuels fabrication and irradiation before the engineering scale tests may be effective and efficient solution.
Oigawa, Hiroyuki; Nishihara, Kenji; Nakayama, Shinichi; Morita, Yasuji
Proceedings of 10th OECD/NEA Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation (CD-ROM), p.123 - 131, 2010/00
To illustrate the benefit of the partitioning and transmutation (PT) technology, several types of the waste management and the geological disposal concepts incorporating PT was discussed in terms of the repository size required to emplace the wastes. It was found that the transmutation of 
Am, which is a long-term heat source, is effective to prevent the inflation of the repository size expected in the case of plutonium utilization. If we intend to reduce the repository size to a larger extent the partitioning of Sr and Cs followed by their long-term (100 - 300 years) storage should be adopted together with the transmutation of MA.
Bh and Db produced in the Cm + 
Na reactionMorita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Haba, Hiromitsu*; Ozeki, Kazutaka*; Kudo, Yuki*; Sato, Nozomi*; Sumita, Takayuki*; Yoneda, Akira*; Ichikawa, Takatoshi*; et al.
Journal of the Physical Society of Japan, 78(6), p.064201_1 - 064201_6, 2009/06
Times Cited Count：30 Percentile：78.34(Physics, Multidisciplinary)Decay properties of an isotope Bh and its daughter nucleus Db produced by the Cm(Na,5
) reaction were studied by using a gas-filled recoil separator coupled with a position-sensitive semiconductor detector. Bh was clearly identified from the correlation of the known nuclide, Db. The obtained decay properties of Bh and Db are consistent with those observed in the 113 chain, which provided further confirmation of the discovery of 113.
113Morimoto, Koji*; Morita, Kosuke*; Kaji, Daiya*; Akiyama, Takahiro*; Goto, Shinichi*; Haba, Hiromitsu*; Ideguchi, Eiji*; Katori, Kenji*; Koura, Hiroyuki; Kudo, Hisaaki*; et al.
RIKEN Accelerator Progress Report, Vol.42, P. 15, 2009/00
In 2003-2007, we had performed an experiment to synthesize an element 113 by a Bi
Zn reaction using a gas-filled recoil ion separator (GARIS) at RIKEN Nishina-Center. In a total of 241 days of net irradiation time experiment, two decay chains were observed and assigned from an isotope 113. The cross section of the Bi(Zn,n)113 reaction was determined to be 31
fb at that time. In order to increase the statistics of the decay property, we continued to produce more decay chains. The experiment was carried out from January 7 to March 31, 2008. The experimental conditions were identical to those used in the previous experiment. Zn ion beam of 353 MeV was extracted from RILAC. The net irradiation time was 83 days and the total dose of Zn was 2.28
. In the present expriment any candidate of 113 was not observed. Then combining the results of the present and previous experiments, the production cross section of 113 was determined to be 22
fb.
Nishihara, Kenji; Nakayama, Shinichi; Morita, Yasuji; Oigawa, Hiroyuki; Iwasaki, Tomohiko*
Journal of Nuclear Science and Technology, 45(1), p.84 - 97, 2008/01
Times Cited Count：40 Percentile：91.3(Nuclear Science & Technology)We studied how cooling in the predisposal storage period may affect the design of the emplacement area in a repository for radioactive wastes produced by a light-water-reactor nuclear system that uses partitioning and/or transmutation (PT) technology. Three different fuel cycle scenarios involving PT technology were analyzed: (1) partitioning process only (separation of some fission products), (2) transmutation process only (separation and transmutation of minor actinides), and (3) both partitioning and transmutation. The necessary predisposal storage periods for some predefined emplacement configurations were determined through transient thermal analysis. For each scenario, we also estimated the storage capacity required for dry storage. The contributions of PT technology on the storage and disposal were discussed holistically, and we noted that the coupled introduction of partitioning and transmutation processes can bring an appreciable reduction in waste management size.
112 by Pb + Zn reactionMorita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Akiyama, Takahiro*; Goto, Shinichi*; Haba, Hiromitsu*; Ideguchi, Eiji*; Katori, Kenji*; Koura, Hiroyuki; Kudo, Hisaaki*; et al.
Journal of the Physical Society of Japan, 76(4), p.043201_1 - 043201_5, 2007/04
Times Cited Count：150 Percentile：95.98(Physics, Multidisciplinary)The production and decay of 112 has been investigated using a gas-filled recoil ion separator in irradiations of Pb targets with Zn beam at 349.5 MeV. We have observed two -decay chains that can be assigned to subsequent decays from 112 produced in the 208 Pb(Zn,n) reaction. After emitting four consecutive -particles, the both chains ended by spontaneous fission decays of 
Rf and decay energies and decay times of the both chains obtained in the present work agree well with those reported by a group at Gesellschaft f
r Schwerionenforschung (GSI), Germany. The present result gives the first clear confirmation of the discovery of 112 and its -decay products 
Ds reported previously.
113Morita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Akiyama, Takahiro*; Goto, Shinichi*; Haba, Hiromitsu*; Ideguchi, Eiji*; Katori, Kenji*; Koura, Hiroyuki; Kikunaga, Hidetoshi*; et al.
Journal of the Physical Society of Japan, 76(4), p.045001_1 - 045001_2, 2007/04
Times Cited Count：199 Percentile：97.44(Physics, Multidisciplinary)The production and decay of 113 has been investigated using a gas-filled recoil ion separator in irradiations of Bi targets with Zn beam at 353 MeV. We have observed one -decay chain that can be assigned to subsequent decays from 113 produced in the Bi(Zn,n) reaction. After emitting four consecutive -particles, the both chains ended by spontaneous fission decays of Db and decay energies and decay times of the both chains obtained in the present work agree well with those reported by our group in 2004. The present result gives the first clear confirmation of the discovery of 113 and its -decay products Rg reported previously.
Morita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Akiyama, Takahiro*; Goto, Shinichi*; Haba, Hiromitsu*; Ideguchi, Eiji*; Kanungo, R.*; Katori, Kenji*; Kikunaga, Hidetoshi*; et al.
AIP Conference Proceedings 891, p.3 - 9, 2007/03
A series of experiments studying the productions and their decays of the heaviest elements have been performed by using a gas-filled recoil separator GARIS at RIKEN. Results on the isotope of the 112th element, 112, and on that of the 113th element, 113, are reviewed. Two decay chains which are assigned to be ones originating from the isotope 112 were observed in the Pb(Zn, n) reaction. The results provide a confirmation of the production and decay of the isotope 112 reported by a research group at GSI, Germany, produced via the same reaction by using a velocity filter. Two decay chains, both consisted of four consecutive alpha decays followed by a spontaneous fission, were observed also in the reaction Bi(Zn, n). Those are assigned to be the convincing candidate events of the isotope of the 113th element, 113, and its daughter nuclei. Rg, Mt, Bh, and Db.
Toya, Yuichi; Washiya, Tadahiro; Koizumi, Kenji; Morita, Shinichi
Proceedings of 14th International Conference on Nuclear Engineering (ICONE-14) (CD-ROM), 6 Pages, 2006/07
Japan Atomic Energy Agency (JAEA) has been leading feasibility study on commercialized fast reactor cycle systems in Japan. In this study, we have proposed a new disassembly technology by mechanical disassembly system that consists of a mechanical cutting step and a wrapper tube pulling step. In the mechanical tool system, high durability mechanical cutter cuts the wrapper tube (Slit-Cut (S/C) operation in circle direction), and then the wrapper tube is pulled out and removed from the fuel assembly. Then the fuel pins are cut (Crop-Cut (C/C) operation at entrance nozzle side) and the entrance nozzle is removed. The fuel pins are transported to the shearing machine in next process. The Fundamental tests were carried out with simulated FBR fuel pins and wrapper tube, and cutting performance and wrapper tube pulling performance has been confirmed by engineering scale. As the results, we established the disassembly procedure and the fundamental design of mechanical disassembly system.
Oigawa, Hiroyuki; Minato, Kazuo; Kimura, Takaumi; Morita, Yasuji; Arai, Yasuo; Nakayama, Shinichi; Nishihara, Kenji
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
JAERI is engaging in the R&D on the Double-strata Fuel Cycle concept in accordance with the results of the check and review on the Partitioning and Transmutation (PT) technology made by the Atomic Energy Commission of Japan in 2000. As for the partitioning process, after the establishment of the "4-group Partitioning Process Concept", an innovative concept called ARTIST is also being studied. As for the fuel technology, minor actinide nitrides such as NpN and AmN were synthesized and their material properties have been measured. To reprocess the irradiated fuel, the pyrochemical process has been studied. The R&D of the accelerator-driven transmutation system are in progress for an accelerator, lead-bismuth, and a subcritical reactor. In addition, JAERI has started the high-intensity proton accelerator project (J-PARC), which includes the Transmutation Experimental Facility (TEF) as the Phase-II. The impact of PT technology on the backend of the nuclear energy utilization is also being discussed.
Nakayama, Shinichi; Morita, Yasuji; Nishihara, Kenji; Oigawa, Hiroyuki
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
The effects of partitioning-transmutation (PT) technology to waste management was assessed based on the chemical and physical properties and estimated amounts of radioactively contaminated wastes that may be generated in the JAERI's PT cycle. The volume of high-level waste after partitioning was about a third that of non-partitioned vitrified waste form. The required repository area was about sixth, which implies increase in capacity of geologic repositories.
