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Kumada, Takayuki; Nakagawa, Hiroshi; Miura, Daisuke; Sekine, Yurina; Motokawa, Ryuhei; Hiroi, Kosuke; Inamura, Yasuhiro; Oku, Takayuki; Oishi, Kazuki*; Morikawa, Toshiaki*; et al.
Hamon, 34(2), p.50 - 53, 2024/05
Spin-contrast-variation (SCV) small-angle neutron scattering (SANS) enabled us to determine structure of nano-ice crystals that were generated in rapidly frozen sugar solution. In the frozen glucose solution, we found that the nano-ice crystals formed a planar structure with a radius larger than several tens of nanometers and a thickness of 2-3 nm, which was close to the critical nucleation size of ice crystals in supercooled water. This result suggests that the glucose molecules were preferentially bound to a specific face of nano-ice crystals, and then blocked the crystal growth perpendicular to that face.
Arima-Osonoi, Hiroshi*; Takata, Shinichi; Kasai, Satoshi*; Ouchi, Keiichi*; Morikawa, Toshiaki*; Miyata, Noboru*; Miyazaki, Tsukasa*; Aoki, Hiroyuki; Iwase, Hiroki*; Hiroi, Kosuke; et al.
Journal of Applied Crystallography, 56(6), p.1802 - 1812, 2023/12
Times Cited Count:6 Percentile:77.05(Chemistry, Multidisciplinary)Kumada, Takayuki; Nakagawa, Hiroshi; Miura, Daisuke; Sekine, Yurina; Motokawa, Ryuhei; Hiroi, Kosuke; Inamura, Yasuhiro; Oku, Takayuki; Oishi, Kazuki*; Morikawa, Toshiaki*; et al.
Journal of Physical Chemistry Letters (Internet), 14(34), p.7638 - 7643, 2023/08
Times Cited Count:0 Percentile:0.00(Chemistry, Physical)The structure of nano-ice crystals in rapidly frozen glucose solution was elucidated by using spin-contrast-variation small-angle neutron scattering, which distinguishes the nano-ice crystal signal from the frozen amorphous solution signal by the polarization-dependent neutron scattering. The analysis revealed that the nano-ice crystals form a planar structure with a diameter exceeding tens of nanometers and a thickness of 1 nm, which is close to the critical nucleation size. This result suggests that the glucose molecules are preferentially bound to a specific face of nano-ice crystals, and then block the crystal growth perpendicular to that face.
Iwase, Hiroki*; Akamatsu, Masaaki*; Inamura, Yasuhiro; Sakaguchi, Yoshifumi*; Morikawa, Toshiaki*; Kasai, Satoshi*; Ouchi, Keiichi*; Kobayashi, Kazuki*; Sakai, Hideki*
Journal of Applied Crystallography, 56(1), p.110 - 115, 2023/02
Times Cited Count:5 Percentile:77.05(Chemistry, Multidisciplinary)With the increasing importance of light-responsive materials, it is vital to analyze the relationship between function and structural changes induced by light irradiation. Small-angle scattering (SAS) is effective for such structural analysis. However, quantitatively capturing local molecular structure formation and molecular reactions at a scale of less than 1 nm via SAS is difficult. In this study, to analyze the structure of non-equilibrium phenomena in light-responsive materials, a new sample environment has been developed for a time-of-flight small- and wide-angle neutron scattering instrument (TAIKAN), comprising a UV-Vis irradiation system, UV-Vis absorption measurement equipment and photodetector. Simultaneous measurement of small-angle neutron scattering and UV-Vis absorption was achieved. This system was used to demonstrate the in situ observation of UV-Vis irradiation-induced structural change of micelles formed by a light-responsive surfactant sample in an aqueous solution.
Kumada, Takayuki; Miura, Daisuke*; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Suzuki, Junichi*; Oku, Takayuki; Torikai, Naoya*; Niizeki, Tomotake*
Journal of Applied Crystallography, 55(5), p.1147 - 1153, 2022/10
Times Cited Count:2 Percentile:30.55(Chemistry, Multidisciplinary)Spin-contrast-variation neutron reflectivity obtains multiple reflectivity curves from a single sample and a single beam source. We used the strong point of the technique to reveal that, although methylated-perhydropolysilazane-derived silica layer has a higher porosity near the interface with acrylic urethane resin, the resin did not permeate the pore network.
Miura, Daisuke*; Kumada, Takayuki; Sekine, Yurina; Motokawa, Ryuhei; Nakagawa, Hiroshi; Oba, Yojiro; Ohara, Takashi; Takata, Shinichi; Hiroi, Kosuke; Morikawa, Toshiaki*; et al.
Journal of Applied Crystallography, 54(2), p.454 - 460, 2021/04
Times Cited Count:1 Percentile:13.30(Chemistry, Multidisciplinary)We developed a spin-contrast-variation neutron powder diffractometry technique that extracts the structure factor of hydrogen atoms, namely, the contribution of hydrogen atoms to a crystal structure factor. Crystals of L-glutamic acid were dispersed in a dpolystyrene matrix containing 4-methacryloyloxy-2,2,6,6,-tetramethyl-1-piperidinyloxy (TEMPO methacrylate) to polarize their proton spins dynamically. The intensities of the diffraction peaks of the sample changed according to the proton polarization, and the structure factor of the hydrogen atoms was extracted from the proton-polarization dependent intensities. This technique is expected to enable analyses of the structures of hydrogen-containing materials that are difficult to determine with conventional powder diffractometry.
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Sahara, Masae*; Suzuki, Junichi*; Miura, Daisuke*; Torikai, Naoya*
J-PARC 20-02; J-PARC MLF Annual Report 2019, p.38 - 40, 2021/00
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
Times Cited Count:4 Percentile:36.02(Chemistry, Multidisciplinary)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.
Kaneko, Fumitoshi*; Kawaguchi, Tatsuya*; Radulescu, A.*; Iwase, Hiroki*; Morikawa, Toshiaki*; Takata, Shinichi; Nishiura, Masayoshi*; Hou, Z.*
Review of Scientific Instruments, 90(9), p.093906_1 - 093906_6, 2019/09
Times Cited Count:5 Percentile:24.29(Instruments & Instrumentation)Tashiro, Koji*; Hanesaka, Makoto*; Yamamoto, Hiroko*; Wasanasuk, K.*; Jayaratri, P.*; Yoshizawa, Yoshinori*; Tanaka, Ichiro*; Niimura, Nobuo*; Kusaka, Katsuhiro*; Hosoya, Takaaki*; et al.
Kobunshi Rombunshu, 71(11), p.508 - 526, 2014/11
Times Cited Count:6 Percentile:20.64(Polymer Science)The crystal structure analysis of various polymer substances has been reviewed on the basis of wide-angle high-energy X-ray and neutron diffraction data. The progress in structural analytical techniques of polymer crystals have been reviewed at first. The structural models proposed so far were reinvestigated and new models have been proposed for various kinds of polymer crystals including polyethylene, poly(vinyl alcohol), poly(lactic acid) and its stereocomplex etc. The hydrogen atomic positions were also clarified by the quantitative analysis of wide-angle neutron diffraction data, from which the physical properties of polymer crystals have been evaluated theoretically. The bonded electron density distribution has been estimated for a polydiacetylene single crystal on the basis of the so-called X-N method or by the combination of structural information derived from X-ray and neutron diffraction data analysis. Some comments have been added about future developments in the field of structure-property relationship determination.
Yamashita, Riyo; Hama, Katsuhiro; Takeuchi, Ryuji; Morikawa, Keita*; Hosoya, Shinichi*; Nakamura, Toshiaki*; Tanaka, Yumiko*
JAEA-Technology 2014-029, 118 Pages, 2014/09
This study is to gain a better understanding of mass transfer phenomena in the geological environment as well as to develop technologies for: measurement of the solute transport parameters, model construction, numerical analysis and validation of all those technologies based on the existing information. As part of solute transport study, laboratory experiments were planned to understand the influence of the geological characteristics of fracture on the solute transport parameters, also understand the differences in test results by the different sizes of the samples used for an experiment, and moreover to validate the parameters obtained by numerical analysis.
Morikawa, Tsuneyasu*; Oshima, Masumi; Sekine, Toshiaki; ; ; ; ; Shibata, Michihiro; Taniguchi, A.*
Physical Review C, 46(1), p.R6 - R9, 1992/07
Times Cited Count:23 Percentile:75.26(Physics, Nuclear)no abstracts in English
Oshima, Masumi; Sekine, Toshiaki; ; ; ; Morikawa, Tsuneyasu*;
Nuclear Instruments and Methods in Physics Research B, 70, p.241 - 244, 1992/00
Times Cited Count:7 Percentile:60.58(Instruments & Instrumentation)no abstracts in English
Takata, Shinichi; Hiroi, Kosuke; Morikawa, Toshiaki*; Arima, Hiroshi*; Yamada, Takeshi*
no journal, ,
The small- and wide-angle neutron scattering instrument (TAIKAN) was installed in the Materials and Life Science Experimental Facility (MLF) of J-PARC, which was designed for efficient measurement in the range from sub-nanometre to micrometre scale. Therefor, TAIKAN is used in various research fields. Recently, the morphology of ion exchange membranes for fuel cells have been much studied using SAXS and WAXS techniques under high-temperature and high-humidity conditions close to the product usage environment. In this study, we measured the humidity dependence of the Nafion film structure at 80C using a Humidity Cell at BL15 TAIKAN. As a result, it was possible to measure the humidity dependence of the matrix, ionomer, and crystal phase in the film. In this presentation, we will report the details of those results, and also report on the development status of TAIKAN.
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Suzuki, Junichi*; Torikai, Naoya*
no journal, ,
Scattering power of neutrons against protons depends remarkably on relative directions of their spins. So, polarized neutron scattering profiles vary as a function of proton polarization of measuring specimen. We can extract fruitful structural information from these profiles. This technique named "spin-contrast variation" has been used to study meso-scale bulk structure using small-angle neutron scattering. Now, we plan to apply the spin-contrast variation technique to study surface structure using neutron reflectivity measurements. The spin-contrast neutron reflectivity measurement will determine surface structure of complex soft materials such as adhesives.
Kumada, Takayuki; Nakagawa, Hiroshi; Miura, Daisuke*; Sekine, Yurina; Motokawa, Ryuhei; Hiroi, Kosuke; Inamura, Yasuhiro; Oku, Takayuki; Oishi, Kazuki*; Morikawa, Toshiaki*; et al.
no journal, ,
The structure of nano-ice crystals in rapidly frozen sugar solution was elucidated by using spin-contrast-variation small-angle neutron scattering, which distinguishes the nano-ice crystal signal from the frozen amorphous solution signal by the polarization-dependent neutron scattering. The analysis revealed that the nano-ice crystals form a planar structure with a diameter exceeding tens of nanometers and a thickness of 1 nm, which is close to the critical nucleation size. This result suggests that the sugar molecules are preferentially bound to a specific face of nano-ice crystals, and then block the crystal growth perpendicular to that face.
Kumada, Takayuki; Akutsu, Kazuhiro*; Kawamura, Yukihiko*; Morikawa, Toshiaki*; Sahara, Masae*; Suzuki, Junichi*; Torikai, Naoya*
no journal, ,
We developed a technique of spin-contrast-variation neutron reflectometry (SCV-NR). Polarized-neutron reflectivity curves of a styrene homopolymer film vary as a function of their proton-polarization, P, coherently with what expected when the films are homogeneously polarized. This result ensures that the SCV-NR curves are not deformed by inhomogeneous P
in the film, but determine the structures of surfaces and interfaces properly. Conventional unpolarized neutron reflectivity UNR and negatively-polarized SCV-NR curves of poly(styrene-block-isoprene) (PSPI) films are reproduced by the model that the film has a flat free surface, but positively-polarized SCV-NR curves are not. We found from the global fit that the holes with the depth corresponding to one period of periodic lamellae are produced on the free surface of the PSPI films, whose reflection is hidden by strong one from the PSPI-Si interface in the UNR and negatively-polarized SCV-NR curves.
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Suzuki, Junichi*; Torikai, Naoya*
no journal, ,
no abstracts in English
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Sahara, Masae*; Suzuki, Junichi*; Torikai, Naoya*
no journal, ,
Scattering power of neutron against proton remarkably depends on relative direction of these spins. Spin contrast variation (SCV) is a technique to determine structure of composite materials from their polarized neutron scattering profiles that vary as a function of proton polarization. Very recently, we succeeded in the first SCV neutron reflectometry measurement. We determined roughness of two surfaces of a thin-film polymer from the SCV neutron reflection curves. We will use this technique to study structures of multilayered films such as coupling agents (glues) between organic and inorganic materials.
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Sahara, Masae*; Suzuki, Junichi*; Torikai, Naoya*
no journal, ,
Scattering power of neutron against proton remarkably depends on relative direction of these spins. Spin contrast variation (SCV) is a technique to determine structure of composite materials from their polarized neutron scattering profiles that vary as a function of proton polarization. Very recently, we succeeded in the first SCV neutron reflectometry measurement. We determined roughness of two surfaces of a thin-film polymer from the SCV neutron reflection curves. We will use this technique to study structures of multilayered films such as coupling agents (glues) between organic and inorganic materials.