Maruyama, Ryuji; Yamazaki, Dai; Aoki, Hiroyuki; Akutsu, Kazuhiro*; Hanashima, Takayasu*; Miyata, Noboru*; Soyama, Kazuhiko; Bigault, T.*; Saerbeck, T.*; Courtois, P.*
Journal of Applied Physics, 130(8), p.083904_1 - 083904_10, 2021/08
Kofu, Maiko; Watanuki, Ryuta*; Sakakibara, Toshiro*; Kawamura, Seiko; Nakajima, Kenji; Matsuura, Masato*; Ueki, Takeshi*; Akutsu, Kazuhiro*; Yamamuro, Osamu*
Scientific Reports (Internet), 11(1), p.12098_1 - 12098_8, 2021/06
Maruyama, Ryuji; Yamazaki, Dai; Akutsu, Kazuhiro*; Hanashima, Takayasu*; Miyata, Noboru*; Aoki, Hiroyuki; Soyama, Kazuhiko
JPS Conference Proceedings (Internet), 33, p.011092_1 - 011092_6, 2021/03
no abstracts in English
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Sahara, Masae*; Suzuki, Junichi*; Miura, Daisuke*; Torikai, Naoya*
J-PARC 20-02, p.38 - 40, 2021/00
Kumada, Takayuki; Miura, Daisuke*; Akutsu, Kazuhiro*; Suzuki, Junichi*; Torikai, Naoya*
Hamon, 30(4), p.207 - 211, 2020/11
We developed a technique of spin-contrast-variation neutron reflectivity (SCV-NR) for structural analyses of multilayer films. The SCV-NR curves of the polystyrene monolayer film were precisely reproduced using a common set of structural parameters and neutron scattering length density at each proton polarization. This result ensures that SCV-NR curves are not deformed by inhomogeneous PH due to the spin-diffusion mechanism. The number of structural parameters of the lamellar microphase-separated poly(styrene-block-isoprene) thin film is too large to determine with a single unpolarized reflectivity curve only. However, these parameters converged through the global analysis of the SCV-NR curves. In this manner, SCV-NR determines the structure of multilayer films while excluding the incorrect structural model that accidentally accounts for a single unpolarized reflectivity curve only.
Akutsu, Kazuhiro*; Kira, Hiroshi*; Miyata, Noboru*; Hanashima, Takayasu*; Miyazaki, Tsukasa*; Kasai, Satoshi*; Yamazaki, Dai; Soyama, Kazuhiko; Aoki, Hiroyuki
Polymers (Internet), 12(10), p.2180_1 - 2180_10, 2020/10
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Sahara, Masae*; Suzuki, Junichi*; Torikai, Naoya*
Journal of Applied Crystallography, 52(5), p.1054 - 1060, 2019/10
We developed a technique of spin-contrast-variation neutron reflectometry (SCV-NR). Polarized-neutron reflectivity curves of film samples vary as a function of their proton-polarization P. The P-dependent reflectivity curves of a polystyrene film was precisely reproduced using a common set of structure parameters and the P-dependent neutron scattering length. The reflectivity curve of poly (styrene-block-isoprene) (PSPI) presented a shoulder attributed to holes with the depth corresponding to one period of periodic lamellae on the free surface only at a specific P. In this way, structural information about specific surfaces or interfaces can be obtained by controlling the P.
Akutsu, Kazuhiro*; Cagnes, M.*; Tamura, Kazuhisa; Kanaya, Toshiji*; Darwish, T. A.*
Physical Chemistry Chemical Physics, 21(32), p.17512 - 17516, 2019/08
We combined the deuterium labeling and neutron reflectivity techniques to determine the fine structure of the electric double layer structure in an imidazolium ionic liquid (IL). For this, a simple and large scale deuteration method for imidazolium ILs was developed, where the deuteration level can be systematically controlled.
Kobayashi, Toru; Akutsu, Kazuhiro*; Nakase, Masahiko*; Suzuki, Shinichi; Shiwaku, Hideaki; Yaita, Tsuyoshi
Separation Science and Technology, 54(13), p.2077 - 2083, 2019/02
Development of separation reagent, which can efficiently separate lanthanides, is of increasing importance because it concerns establishment of purification and recycle techniques rare-earth elements. In our research group, several hetero donor type ligands, which have both oxygen and heterocyclic nitrogen atoms as donor atoms, were developed and revealed that this type of ligands show the selective complexation with specific lanthanide. In this paper, we will discuss the lanthaides complexation properties of the hetero donor type ligand containing benzimidazole group as nitrogen donor (-methyl--phenyl-2-(1-benzimidazol-2-yl)-pyridine-6-carboxamide) based on structural investigation by crystallography.
Maruyama, Ryuji; Yamazaki, Dai; Akutsu, Kazuhiro*; Hanashima, Takayasu*; Miyata, Noboru*; Aoki, Hiroyuki; Takeda, Masayasu; Soyama, Kazuhiko
Nuclear Instruments and Methods in Physics Research A, 888, p.70 - 78, 2018/04
The multilayer structure of Fe/Si and Fe/Ge systems fabricated by ion beam sputtering (IBS) was investigated using X-ray and polarized neutron reflectivity measurements and scanning transmission electron microscopy with energy-dispersive X-ray analysis. The obtained result revealed that the incorporation of sputtering gas particles (Ar) in the Ge layer gives rise to a marked reduction in the neutron scattering length density (SLD) and contributes to the SLD contrast between the Fe and Ge layers almost vanishing for spin-down neutrons. This leads to a possibility of fine-tuning of the SLD for the IBS, which is required to realize a high polarization efficiency of a neutron polarizing supermirror. Fe/Ge polarizing supermirror with fabricated showed a spin-up reflectivity of 0.70 at the critical momentum transfer. The polarization was higher than 0.985 for the range where the correction for the polarization inefficiencies of the beamline works properly.
Akutsu, Kazuhiro*; Adachi, Motoyasu*; Kawakita, Yukinobu
JAEA-Review 2018-002, 36 Pages, 2018/03
Since J-PARC started operation for user programs with high-intensity pulsed neutron beams, many material and life science studies have been carried out at J-PARC. Since partial or complete deuteration of organic compounds for contrast variation in the scattering length densities of materials is one of the most effective techniques in the application of neutron scattering analysis, deuterated materials have led to significant progress in our understanding of the structure of novel organic materials. Aiming at accelerating development of deuteration activities in our country, an international workshop "Deuterated Materials Enhancing Neutron Science for Structure Function Applications" was held as a J-PARC Workshop at Ibaraki Quantum Beam Research Center from 19th October to 20th October in 2017. In this workshop, the chemical/biological deuteration activities and recent scientific results of deuterated materials enhancing neutron study in Japan and other countries were discussed by domestic/foreign deuteration and neutron scientists. This is a report of the workshop summarized by organizers.
Mu, J.*; Motokawa, Ryuhei; Akutsu, Kazuhiro*; Nishitsuji, Shotaro*; Masters, A. J.*
Journal of Physical Chemistry B, 122(4), p.1439 - 1452, 2018/02
Motokawa, Ryuhei; Kobayashi, Toru; Endo, Hitoshi*; Ikeda, Takashi; Yaita, Tsuyoshi; Suzuki, Shinichi; Narita, Hirokazu*; Akutsu, Kazuhiro*; Heller, W. T.*
Journal of Nuclear Science and Technology, 53(8), p.1205 - 1211, 2016/08
Mu, J.*; Motokawa, Ryuhei; Williams, C. D.*; Akutsu, Kazuhiro*; Nishitsuji, Shotaro*; Masters, A. J.*
Journal of Physical Chemistry B, 120(23), p.5183 - 5193, 2016/06
Hattori, Takanori; Akutsu, Kazuhiro*; Suzuki, Junichi*
Bunseki, 2015(2), p.58 - 64, 2015/02
In the J-PARC MLF, 18 beamlines has been constructed and many studies on scientific and industrial use have been performed. This paper introduces the high-pressure science at high-pressure neutron diffractometer "PLANET" and surface/interface structure analysis at vertical sample geometry polarized neutron reflectometer "SHARAKU".
Akutsu, Kazuhiro*; Ohara, Takashi
Bunseki, 2014(11), p.617 - 621, 2014/11
no abstracts in English
Akutsu, Kazuhiro*; Suzuki, Shinichi; Kobayashi, Toru; Shiwaku, Hideaki; Okamoto, Yoshihiro; Yaita, Tsuyoshi
Solvent Extraction Research and Development, Japan, 20, p.105 - 114, 2013/00
Kobayashi, Toru; Yaita, Tsuyoshi; Suzuki, Shinichi; Shiwaku, Hideaki; Okamoto, Yoshihiro; Akutsu, Kazuhiro*; Nakano, Yoshiharu*; Fujii, Yuki*
Separation Science and Technology, 45(16), p.2431 - 2436, 2010/11
Numakura, Masahiko; Yaita, Tsuyoshi; Shiwaku, Hideaki; Suzuki, Shinichi; Kobayashi, Toru*; Akutsu, Kazuhiro; Madden, P. A.*; Okamoto, Yoshihiro
JAEA-Research 2009-003, 26 Pages, 2009/04
We investigated the mixing behavior of molten TbCl in LiCl-KCl eutectuic melt by MD simulation. Also, simulation of molten YCl and LaCl systems were performed to elucidate the difference of the structural change by the difference in cation size (YTbLa). The coordination number of the molten pure YCl, TbCl and LaCl are mainly 6, 7 and 8 respectively. We consider that, in the molten pure state, the coordination number is influenced by the cation size. However, independent of cation size, the molten MCl tend to be formed the stable 6-fold structure by the mixing with LiCl-KCl eutectic. And, MD simulations on MCl-LiCl and MCl-KCl systems revealed that the mixing effect was different between LiCl and KCl.
Sumita, Junya; Sawa, Kazuhiro; Mogi, Haruyoshi; ; Kitami, Takayuki; Akutsu, Yoichi; *; *; *
JAERI-Research 99-054, p.41 - 0, 1999/09
no abstracts in English