JOPSS - Search Results

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

https://doi.org/10.1107/S1600576721000303

Times Cited Count：0 Percentile：0.02(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.

Journal Articles

Revealing defect-induced spin disorder in nanocrystalline Ni

Bersweiler, M.*; Sinaga, E. P.*; Peral, I.*; Adachi, Nozomu*; Bender, P.*; Steinke, N.-J.*; Gilbert, E. P.*; Todaka, Yoshikazu*; Michels, A.*; Oba, Yojiro

Physical Review Materials (Internet), 5(4), p.044409_1 - 044409_7, 2021/04

https://doi.org/10.1103/PhysRevMaterials.5.044409

Times Cited Count：1 Percentile：69.4(Materials Science, Multidisciplinary)

Journal Articles

Commissioning of Versatile Compact Neutron Diffractometer (VCND) at the B-3 beam port of Kyoto University Research Reactor (KUR)

Mori, Kazuhiro*; Okumura, Ryo*; Yoshino, Hirofumi*; Kanayama, Masaya*; Sato, Setsuo*; Oba, Yojiro; Iwase, Kenji*; Hiraka, Haruhiro*; Hino, Masahiro*; Sano, Tadafumi*; et al.

JPS Conference Proceedings (Internet), 33, p.011093_1 - 011093_6, 2021/03

https://doi.org/10.7566/JPSCP.33.011093

no abstracts in English

Journal Articles

Effect of grain boundary on the friction coefficient of pure Fe under the oil lubrication

Adachi, Nozomu*; Matsuo, Yasutaka*; Todaka, Yoshikazu*; Fujimoto, Mikiya*; Hino, Masahiro*; Mitsuhara, Masatoshi*; Oba, Yojiro; Shiihara, Yoshinori*; Umeno, Yoshitaka*; Nishida, Minoru*

Tribology International, 155, p.106781_1 - 106781_9, 2021/03

https://doi.org/10.1016/j.triboint.2020.106781

Times Cited Count：0 Percentile：0(Engineering, Mechanical)

Journal Articles

Introduction to SANS-J and PNO

Kumada, Takayuki; Motokawa, Ryuhei; Nakagawa, Hiroshi; Oba, Yojiro; Sekine, Yurina

Hamon, 31(1), p.5 - 6, 2021/02

no abstracts in English

Journal Articles

Anomalous magnetic anisotropy and magnetic nanostructure in pure Fe induced by high-pressure torsion straining

Oba, Yojiro; Adachi, Nozomu*; Todaka, Yoshikazu*; Gilbert, E. P.*; Mamiya, Hiroaki*

Physical Review Research (Internet), 2(3), p.033473_1 - 033473_6, 2020/11

https://doi.org/10.1103/PhysRevResearch.2.033473

Journal Articles

Local structure investigations of accumulated damage in irradiated MgAl $_{2}$ O $_{4}$

Yoshioka, Satoru*; Tsuruta, Konosuke*; Yamamoto, Tomokazu*; Yasuda, Kazuhiro*; Matsumura, Sho*; Sugiyama, Takeharu*; Oba, Yojiro; Ishikawa, Norito; Kobayashi, Eiichi*; Okudaira, Koji*

Journal of the American Ceramic Society, 103(8), p.4654 - 4663, 2020/08

https://doi.org/10.1111/jace.17101

Times Cited Count：2 Percentile：40.39(Materials Science, Ceramics)

X-ray absorption near edge structure (XANES) and small-angle X-ray scattering (SAXS) reveal the damaged structures in MgAl $_{2}$ O $_{4}$ spinel induced by swift heavy ions. SAXS indicates the formation of ion tracks with cylindrical shape with a diameter of 5 nm. XANES indicates the cationic disordering between tetrahedral and octahedral sites by the irradiation. Quantitative analysis of XANES also reveals that cations preferably occupy the octahedral sites at high fluence.

Journal Articles

Nanostructural characterization of oleyl acid phosphate in poly--olefin using small-angle X-ray scattering

Oba, Yojiro; Motokawa, Ryuhei; Hino, Masahiro*; Adachi, Nozomu*; Todaka, Yoshikazu*; Inoue, Rintaro*; Sugiyama, Masaaki*

Chemistry Letters, 49(7), p.823 - 825, 2020/07

https://doi.org/10.1246/cl.200204

Times Cited Count：0 Percentile：0(Chemistry, Multidisciplinary)

Journal Articles

Neutron scattering and imaging using neutron transmission spectra

Oba, Yojiro

Hamon, 30(2), p.90 - 93, 2020/05

no abstracts in English

Journal Articles

Neutron transmission spectrum of liquid lead bismuth eutectic

Oba, Yojiro; Ito, Daisuke*; Saito, Yasushi*; Onodera, Yohei*; Parker, J. D.*; Shinohara, Takenao; Oikawa, Kenichi

Materials Research Proceedings, Vol.15, p.160 - 164, 2020/02

https://doi.org/10.21741/9781644900574-25

Lead Bismuth eutectic (LBE) is a promising candidate of the coolant for accelerator driven system (ADS) and fast breeder reactor. Neutron transmission imaging is a powerful technique to investigate the LBE in flow channel. However, previous studies have focused on the analysis of the neutron transmission spectra due to Bragg diffraction (Bragg edge transmission) from the solid phase of the LBE. If the neutron transmission spectra due to the diffraction from a liquid phase can be observed, it is useful to study the behavior of the molten LBE in the flow channel. Therefore, the energy-resolved neutron transmission imaging measurements of the molten LBE was carried out. The observed neutron transmission spectra can be explained by those calculated from the scattering profiles of the molten LBE. This indicates that the structure of the molten LBE can be characterized and mapped using the neutron transmission imaging.

Journal Articles

Anomalous small-angle X-ray scattering (ASAXS) study of irradiation-induced nanostructure change in Fe-ion beam irradiated oxide dispersion-strengthened (ODS) steel

Kumada, Takayuki; Oba, Yojiro; Motokawa, Ryuhei; Morooka, Satoshi; Tominaga, Aki; Tanida, Hajime; Shobu, Takahisa; Konno, Azusa; Owada, Kenji*; Ono, Naoko*; et al.

Journal of Nuclear Materials, 528, p.151890_1 - 151890_7, 2020/01

https://doi.org/10.1016/j.jnucmat.2019.151890

Times Cited Count：0 Percentile：0.01(Materials Science, Multidisciplinary)

We have developed an anomalous small-angle X-ray scattering (ASAXS) diffractometer in SPring-8 to investigate irradiation-induced nanostructural change in ion-beam irradiated stainless steel. A thermally-aged MA956 stainless steel sample displays power-law scattering that follows the Porod law at the magnitude of scattering vector, Q, below 0.5 nm and an overlapped shoulder around 0.7 nm. After the ion-beam irradiation, the intensity of the shoulder remained unchanged, whereas that of the power-law scattering nearly doubled. This result indicates that none of the structural parameters of the Cr-rich nanoprecipitates, such as the number density, size, and interface roughness, were changed by the irradiation.

Journal Articles

Structural and electrochemical features of (Li $_{2}$ S) $_{x}$ (SiS $_{2}$ ) $_{100-x}$ superionic glasses

Mori, Kazuhiro*; Iwase, Kenji*; Oba, Yojiro; Ikeda, Kazutaka*; Otomo, Toshiya*; Fukunaga, Toshiharu*

Solid State Ionics, 344, p.115141_1 - 115141_10, 2020/01

https://doi.org/10.1016/j.ssi.2019.115141

Times Cited Count：0 Percentile：0(Chemistry, Physical)

no abstracts in English

Journal Articles

Characterization of BaZrO $_{3}$ nanocolumns in Zr-added (Gd,Y)Ba $_{2}$ Cu $_{3}$ Ox superconductor tape by anomalous small-angle X-ray scattering

Oba, Yojiro; Sasaki, Hirokazu*; Yamazaki, Satoshi*; Nakasaki, Ryusuke*; Onuma, Masato*

Superconductor Science and Technology, 32(5), p.055011_1 - 055011_5, 2019/05

https://doi.org/10.1088/1361-6668/ab0f55

Times Cited Count：0 Percentile：0(Physics, Applied)

Journal Articles

Advanced analysis technology for new material and product development

Sasaki, Hirokazu*; Nishikubo, Hideo*; Nishida, Shinsuke*; Yamazaki, Satoshi*; Nakasaki, Ryusuke*; Isomatsu, Takemi*; Minato, Ryuichiro*; Kinugawa, Kohei*; Imamura, Akihiro*; Otomo, Shinya*; et al.

Furukawa Denko Jiho, (138), p.2 - 10, 2019/02

https://www.furukawa.co.jp/rd/review/fj138/fj138_02.pdf

no abstracts in English