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Rh
Sn
Iwasa, Kazuaki*; Suyama, Kazuya*; Kawamura, Seiko; Nakajima, Kenji; Raymond, S.*; Steffens, P.*; Yamada, Akira*; Matsuda, Tatsuma*; Aoki, Yuji*; Kawasaki, Ikuto; et al.
Physical Review Materials (Internet), 7(1), p.014201_1 - 014201_11, 2023/01
Times Cited Count：2 Percentile：66.84(Materials Science, Multidisciplinary)Temleitner, L.*; Hattori, Takanori; Abe, Jun*; Nakajima, Yoichi*; Pusztai, L.*
Molecules (Internet), 26(5), p.1218_1 - 1218_12, 2021/03
Times Cited Count：2 Percentile：14.19(Biochemistry & Molecular Biology)Total structure factors of per-deuterated methanol and heavy water, CDOD and D
O, have been determined across the entire composition range at pressures of up to 1.2 GPa, by neutron diffraction. Largest variations due to increasing pressure were observed below 
5 
, mostly as shifts of the first and second maxima. Molecular dynamics computer simulations been conducted at the experimental pressures to interpret neutron diffraction results. The peak shifts mentioned above could be qualitatively reproduced by simulations. In order to reveal the influence of changing pressure on the local intermolecular structure, simulated structures have been analyzed in terms of hydrogen bond related partial radial distribution functions and size distributions of hydrogen bonded cyclic entities. Distinct differences between pressure dependent structures of water-rich and methanol-rich composition regions have been revealed.
Nakajima, Kenji; Kawakita, Yukinobu; Ito, Shinichi*; Abe, Jun*; Aizawa, Kazuya; Aoki, Hiroyuki; Endo, Hitoshi*; Fujita, Masaki*; Funakoshi, Kenichi*; Gong, W.*; et al.
Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12
The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC), is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.
Theis, C.*; Carbonez, P.*; Feldbaumer, E.*; Forkel-Wirth, D.*; Jaegerhofer, L.*; Pangallo, M.*; Perrin, D.*; Urscheler, C.*; Roesler, S.*; Vincke, H.*; et al.
EPJ Web of Conferences, 153, p.08018_1 - 08018_5, 2017/09
Times Cited Count：0 Percentile：0.03(Nuclear Science & Technology)At CERN, gas-filled ionization chambers PTW-34031 (PMI) are commonly used in radiation fields including neutrons, protons and 
-rays. A response function for each particle is calculated by the radiation transport code FLUKA. To validate a response function to high energy neutrons, benchmark experiments with quasi mono-energetic neutrons have been carried out at RCNP, Osaka University. For neutron irradiation with energies below 200 MeV, very good agreement was found comparing the FLUKA simulations and the measurements. In addition it was found that at proton energies of 250 and 392 MeV, results calculated with neutron sources underestimate the experimental data due to a non-negligible gamma component originating from the target 
Li(p,n)Be reaction.
Matsumoto, Tetsuro*; Masuda, Akihiko*; Nishiyama, Jun*; Harano, Hideki*; Iwase, Hiroshi*; Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Yashima, Hiroshi*; Nakane, Yoshihiro; et al.
Progress in Nuclear Science and Technology (Internet), 4, p.332 - 336, 2014/04
Recently, many high-energy accelerators are used for various fields. Shielding data for high-energy neutrons are therefore very important from the point of view of radiation protection in high energy accelerator facilities. However, the shielding experimental data for high energy neutrons above 100 MeV are very poor both in quality and in quantity. In this study, neutron penetration spectral fluence and ambient dose through iron and concrete shields were measured with a Bonner sphere spectrometer (BSS). Quasi-monoenergetic neutrons were produced by the Li(p,xn) reaction by bombarding a 1-cm thick Li target with 246-MeV and 389-MeV protons in the Research Center for Nuclear Physics (RCNP) of the Osaka University. Shielding materials are iron blocks with a thickness from 10 cm to 100 cm and concrete blocks with a thickness from 25 cm to 300 cm.
Hagiwara, Masayuki*; Iwase, Hiroshi*; Iwamoto, Yosuke; Satoh, Daiki; Matsumoto, Tetsuro*; Masuda, Akihiko*; Yashima, Hiroshi*; Nakane, Yoshihiro; Nakashima, Hiroshi; Sakamoto, Yukio; et al.
Progress in Nuclear Science and Technology (Internet), 4, p.327 - 331, 2014/04
We have developed several hundreds of MeV p-Li quasi-monoenergetic neutron fields in the Research Center for Nuclear Physics (RCNP), Osaka University, Japan. In this study, we extended the measurements to higher energy with a p-Li quasi-monoenergetic neutron source, which was produced from a 1.0-cm-thick lithium target bombarded with 246 and 389 MeV protons, using a larger NE213 scintillator of 25.4-cm in diameter and 25.4-cm in thickness. The large NE213 have good energy resolution for high energy neutrons, because it can stop recoil protons up to 180 MeV. The measured data are compared with the Monte-Carlo codes (PHITS with JENDL-HE data library) in the energy spectra, time spectra and the attenuation length of the peak neutrons. This comparison shows good agreement between experiments and calculations. The attenuation length estimated from the well-fitted curves with single exponential form will be useful for the practical shielding design of high energy accelerator facilities.
Nakane, Yoshihiro; Hagiwara, Masayuki*; Iwamoto, Yosuke; Iwase, Hiroshi*; Satoh, Daiki; Sato, Tatsuhiko; Yashima, Hiroshi*; Matsumoto, Tetsuro*; Masuda, Akihiko*; Nunomiya, Tomoya*; et al.
Progress in Nuclear Science and Technology (Internet), 4, p.704 - 708, 2014/04
no abstracts in English
Nakamura, Mitsutaka; Kambara, Wataru; Krist, T.*; Shinohara, Takenao; Ikeuchi, Kazuhiko*; Arai, Masatoshi; Kajimoto, Ryoichi; Nakajima, Kenji; Tanaka, Hiromichi; Suzuki, Junichi*; et al.
Nuclear Instruments and Methods in Physics Research A, 737, p.142 - 147, 2014/02
Times Cited Count：3 Percentile：26.92(Instruments & Instrumentation)The efficiency of inelastic neutron scattering measurements using a chopper spectrometer can be markedly improved by utilizing multiple incident energies (Multi-Ei method). However, in conventional chopper systems, optimization of the experimental condition for all incident energies is absolutely impossible. We developed a new Fermi chopper with a supermirror-coated slit package in order to overcome the problem and experimentally demonstrated that the full optimization of the experimental condition for multiple incident energies is nearly achieved.
He/
He ratios along a high strain rate zone, central JapanUmeda, Koji; Kusano, Tomohiro; Ninomiya, Atsushi*; Asamori, Koichi; Nakajima, Junichi*
Journal of Asian Earth Sciences, 73, p.95 - 102, 2013/09
Times Cited Count：4 Percentile：12.21(Geosciences, Multidisciplinary)A linear zone with high strain rates along the Japan Sea coast, the Niigata-Kobe Tectonic Zone (NKTZ), is considered to be associated with rheological heterogeneities in the lower crust and/or upper mantle. Helium isotope variations along the NKTZ reveal a close association with the geophysical evidence for rheological heterogeneities in the crust and mantle. In the northern NKTZ where two large inland earthquakes occurred recently, there appear to be many samples with He/He ratios significantly higher than those observed in the fore-arc side of northeast Japan. A plausible source of mantle helium could be attributed to upward mobilization of aqueous fluids generated by dehydration of the subducting Pacific Plate slab.
H2AX foci caused by heavy ion particle traversal; Distribution between core track versus non-track damageNakajima, Nakako*; Brunton, H.*; Watanabe, Ritsuko; Shrikhande, A.*; Hirayama, Ryoichi*; Matsufuji, Naruhiro*; Fujimori, Akira*; Murakami, Takeshi*; Okayasu, Ryuichi*; Jeggo, P.*; et al.
PLOS ONE (Internet), 8(8), p.e70107_1 - e70107_14, 2013/08
Times Cited Count：63 Percentile：90.94(Multidisciplinary Sciences)Heavy particle irradiation can produce complex DNA double strand breaks (DSBs) within the particle trajectory. Additionally, secondary electrons, termed delta-electrons, can create low linear energy transfer (LET) damage distant from the track. Using imaging with deconvolution, we show that at 8 hours after exposure to Fe ions, H2AX foci forming at DSBs within the particle track are large and encompass multiple smaller and closely localised foci, which we designate as clustered H2AX foci. We also identified simple H2AX foci distant from the track. They are rapidly repaired. Clustered H2AX foci induced by heavy particle radiation cause prolonged checkpoint arrest compared to simple H2AX foci. However, mitotic entry was observed when 
10 clustered foci remain. Thus, cells can progress into mitosis with multiple clusters of DSBs following the traversal of a heavy particle.
Arai, Masatoshi; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Nakajima, Kenji; Shibata, Kaoru; Takahashi, Nobuaki; Suzuki, Junichi*; Takata, Shinichi; Yamada, Takeshi*; et al.
Journal of the Physical Society of Japan, 82(Suppl.A), p.SA024_1 - SA024_14, 2013/01
Times Cited Count：7 Percentile：47.36(Physics, Multidisciplinary)The paper describes developments of neutron scattering instruments in J-PARC neutron facility, which is a short pulse spallation source operated at a repetition rate 25 Hz and has a proton power 1 MW. New concept has been adopted to utilize high intensity coupled moderator even for a high resolution inelastic scattering instruments by taking a pulse shaping chopper system. Advanced technique has been also realized by taking an ability of event-recording system altogether with an improvement of a chopper system, realizing multi-Ei method. The paper also touches upon a general design concept for diffractometers in accordance with the source characteristics.
Masuda, Akihiko*; Matsumoto, Tetsuro*; Harano, Hideki*; Nishiyama, Jun*; Iwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Iwase, Hiroshi*; Yashima, Hiroshi*; Nakamura, Takashi*; et al.
IEEE Transactions on Nuclear Science, 59(1), p.161 - 166, 2012/02
Times Cited Count：12 Percentile：66.47(Engineering, Electrical & Electronic)In this study, responses of Bonner sphere spectrometer (BSS) for 245 and 388 MeV neutrons was measured at RCNP, Osaka University. The neutrons are generated in the Li(p,n) reaction and its spectra consist of a high-energy peak and a continuum down to the low energy. Therefore, the observed counts of BSS caused by the continuum need to be subtracted. Adjusting a Li target angle and a collimator position, 0 deg and 30 deg component of generated neutron are available. While the 0 deg component contains both the peak and the continuum, the 30 deg component is considered to contain only the continuum. Therefore, the response of the peak is obtained. The spectra were measured using the time-of-flight (TOF) method with a NE213 scintillator.
Honda, Mitsuru; Fukuyama, Atsushi*; Nakajima, Noriyoshi*
Europhysics Conference Abstracts (Internet), 36F, p.P5.014_1 - P5.014_4, 2012/00
Watanabe, So; Senzaki, Tatsuya; Shibata, Atsuhiro; Nomura, Kazunori; Koma, Yoshikazu; Nakajima, Yasuo
Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 6 Pages, 2011/12
Extraction chromatography experiments with two promising flow-sheets on genuine high level liquid wastes were carried out for demonstrating the feasibility of the method. One flow-sheet consists of CMPO/SiO-P and HDEHP/SiO-P adsorbent columns, and the other consists of TODGA/ SiO-P and isoHex-BTP/SiO-P adsorbent columns. Although recovery yields of MA and decontamination factors of FPs obtained by those experiments were lower than the required values, the second flow-sheet is expected to achieve the required performance providing that some minor improvements on the flow-sheet or the adsorbents are applied.
Honda, Mitsuru; Fukuyama, Atsushi*; Nakajima, Noriyoshi*
Journal of the Physical Society of Japan, 80(11), p.114502_1 - 114502_14, 2011/11
Times Cited Count：4 Percentile：33.65(Physics, Multidisciplinary)Kishida, Kiyoshi*; Hosoda, Takashi*; Sawada, Atsushi; Sato, Hisashi; Nakashima, Shinichiro*; Yasuhara, Hideaki*
Harmonising Rock Engineering and the Environment, p.1327 - 1330, 2011/10
Although it is generally known that a natural rock fracture indicates a complex aperture distribution, the fracture is an ideal representation of the parallel plate model. The cubic law is applied to evaluate the hydraulic properties of fractured rock. From several previous research works, it is known that the cubic law can be applied when the Reynolds number is less than 1.0 and that the advection term can basically be ignored in such fracture flows. In this research work, two-dimensional seepage flow analyses, using the authors' proposed 2D model which is considered with the advection term, are carried out for single fracture hydro-conductivity experiments under conditions which allow for the application of the cubic law. From the numerical results, the validity of the 2D model is discussed along with the local Reynolds number and the application of the cubic law.
Kameo, Yutaka; Ishimori, Kenichiro; Haraga, Tomoko; Shimada, Asako; Katayama, Atsushi; Nakashima, Mikio*; Takahashi, Kuniaki
Nihon Genshiryoku Gakkai Wabun Rombunshi, 10(3), p.216 - 225, 2011/09
Analytical methods have been developed for simple and rapid determination of radioactive nuclides, which are selected as important nuclides for safety assessment of disposal of wastes generated from research facilities. We advanced the development of a high-efficiency non-destructive measurement technique for -ray emitting nuclides, simple and rapid methods for pretreatment of hard-to dissolve samples and subsequent radiochemical separations, and rapid determination methods for long-lived nuclides. In order to establish a system to analyze the important nuclides in various kinds of samples, actual radioactive wastes such as concentrated liquid waste, activated concrete, and metal pipes, were analyzed by the present method. The results showed that the present method was well suited for a rapid and simple determination of low-level radioactive wastes generated from research facilities.
from 140 MeV proton incident reactionsIwamoto, Yosuke; Satoh, Daiki; Nakane, Yoshihiro; Nakashima, Hiroshi; Endo, Akira; Sakamoto, Yukio; Hagiwara, Masayuki*; Iwase, Hiroshi*; Yashima, Hiroshi*; Tamii, Atsushi*; et al.
Journal of the Korean Physical Society, 59(2), p.1753 - 1756, 2011/08
Times Cited Count：2 Percentile：20.1(Physics, Multidisciplinary)Neutron production cross sections of carbon and iron targets for 140 MeV proton at 180 were measured at the RCNP cyclotron facility. The neutron energy spectra were obtained by using the time-of-flight technique in the energy range above 1 MeV. The results of carbon and iron targets were compared with experimental data for 113 MeV (p,xn) reactions at 150 deg by Meier et al. Our data gave good agreements with them in spite of different incident energies and angles. Calculations were performed with different intranuclear cascade models (Bertini, ISOBAR, and JQMD) implemented in the PHITS code. Calculated results with the ISOBAR and JQMD models roughly agreed with the experimental data for iron targets, although Bertini could not reproduce the high energy neutrons above 10 MeV.
Honda, Mitsuru; Fukuyama, Atsushi*; Nakajima, Noriyoshi*
Plasma and Fusion Research (Internet), 6, p.1403008_1 - 1403008_11, 2011/05
A neoclassical transport model compatible with a system of two-fluid equations is proposed. The model is based on the moment approach and is capable of accurately reproducing important neoclassical properties through a simple expression of the neoclassical viscosity tensor, with the aid of the NCLASS module. Applying neoclassical transport theory in a fluid context, we obtain good agreement on first-order flows, poloidal flows, neoclassical resistivity, bootstrap current and particle flux from TASK/TX and NCLASS.
Li(p,n) reactions at 246-389 MeVIwamoto, Yosuke; Hagiwara, Masayuki*; Satoh, Daiki; Iwase, Hiroshi*; Yashima, Hiroshi*; Itoga, Toshiro*; Sato, Tatsuhiko; Nakane, Yoshihiro; Nakashima, Hiroshi; Sakamoto, Yukio; et al.
Proceedings of 10th Meeting of the Task Force on Shielding Aspects of Accelerators, Targets and Irradiation Facilities (SATIF-10), p.53 - 61, 2011/03
The neutron energy spectra penetrating 10 to 100 cm thick iron and 25 to 200 cm thick concrete shields have been measured using 138, 243 and 387 MeV quasi-monoenergetic neutron sources at the Research Center for Nuclear Physics (RCNP) facility, Osaka University. The source neutrons were produced from a 1 cm thick lithium target bombarded with 140, 245 and 388 MeV protons. Two types of NE213 liquid organic scintillators and Bonner ball neutron spectrometers were used for the neutron energy spectrum measurement. The TOF and unfolding methods were applied to estimate the energy spectra behind the shield in the peak energy region and continuous energy region, respectively. We have also measured the neutron energy spectra and angular distribution of the source neutron above 1 MeV in the angular range from 0 to 30 with the TOF method. All measured data were compared with the PHITS Monte Carlo calculations.
