JOPSS - Search Results

Journal Articles

In situ transmission electron microscopy observation of melted germanium encapsulated in multilayer graphene

Suzuki, Seiya; Nemoto, Yoshihiro*; Shiiki, Natsumi*; Nakayama, Yoshiko*; Takeguchi, Masaki*

Annalen der Physik, 535(9), p.2300122_1 - 2300122_12, 2023/09

https://doi.org/10.1002/andp.202300122

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

Journal Articles

The Formation mechanism of radiocesium-bearing microparticles derived from the Fukushima Daiichi Nuclear Power Plant using electron microscopy

Hagiwara, Hiroki; Kondo, Keietsu; Hidaka, Akihide

Journal of Radioanalytical and Nuclear Chemistry, 331(12), p.5905 - 5914, 2022/12

https://doi.org/10.1007/s10967-022-08434-7

Times Cited Count：3 Percentile：50.96(Chemistry, Analytical)

Journal Articles

Accumulation mechanisms of radiocaesium within lichen thallus tissues determined by means of microscale localisation observation

Dohi, Terumi; Iijima, Kazuki; Machida, Masahiko; Suno, Hiroya*; Omura, Yoshihito*; Fujiwara, Kenso; Kimura, Shigeru*; Kanno, Futoshi*

PLOS ONE (Internet), 17(7), p.e0271035_1 - e0271035_21, 2022/07

https://doi.org/10.1371/journal.pone.0271035

Times Cited Count：1 Percentile：13.44(Multidisciplinary Sciences)

Journal Articles

Characterization of radiocesium-bearing microparticles with different morphologies in soil around the Fukushima Daiichi Nuclear Power Plant

Hagiwara, Hiroki; Funaki, Hironori; Shiribiki, Natsu*; Kanno, Marina*; Sanada, Yukihisa

Journal of Radioanalytical and Nuclear Chemistry, 331(1), p.415 - 426, 2022/01

https://doi.org/10.1007/s10967-021-08061-8

Times Cited Count：7 Percentile：70.8(Chemistry, Analytical)

Journal Articles

Microstructural stability of ODS steel after very long-term creep test

Oka, Hiroshi; Tanno, Takashi; Yano, Yasuhide; Otsuka, Satoshi; Kaito, Takeji; Tachi, Yoshiaki

Journal of Nuclear Materials, 547, p.152833_1 - 152833_7, 2021/04

https://doi.org/10.1016/j.jnucmat.2021.152833

Times Cited Count：7 Percentile：75.99(Materials Science, Multidisciplinary)

In order to evaluate the stability of nano-sized oxide particles and matrix structure of ODS cladding tube, which are the determinants of their high temperature strength, the microstructural observation was carried out after internal pressurized creep test at 700 $^{circ}$ C for over 45,000 hours. The specimens were the as-received and crept specimens of 9Cr-ODS steel with tempered martensite and 12Cr-ODS steel with recrystallized ferrite. Small platelet was cut out from the crept pressurized tube, then thinned to foil. Microstructural observation was conducted with TEM JEOL 2010F. As a result of the observation, it was confirmed that the size and number density of the nano-sized particles were almost unchanged even after the creep test. In addition, the tempered martensite structure, which is one of the determinants of the creep strength of 9Cr-ODS steel, was not significantly different between the as-received and crept specimen, indicating the stability of their matrix structure.

Journal Articles

Inner structure and inclusions in radiocesium-bearing microparticles emitted in the Fukushima Daiichi Nuclear Power Plant accident

Okumura, Taiga*; Yamaguchi, Noriko*; Dohi, Terumi; Iijima, Kazuki; Kogure, Toshihiro*

Microscopy, 68(3), p.234 - 242, 2019/06

https://doi.org/10.1093/jmicro/dfz004

Times Cited Count：11 Percentile：67.6(Microscopy)

Radiocesium-bearing microparticles (CsMPs), consisting substantially of silicate glass, were released to the environment during the Fukushima nuclear accident in March 2011. We investigated a total of nine CsMPs using transmission electron microscopy (TEM) and inferred the atmosphere in the reactors during the accident. From elemental mapping using energy-dispersive X-ray spectrometry, Fe and Zn showing radial inhomogeneities were found in the CsMPs, in addition to the Cs that had been previously reported. Four of the CsMPs included submicron crystals, which were identified as chromite, franklinite, acanthite, molybdenite, and hessite. The chromium-containing spinels, chromite and franklinite, indicated the presence of ferrous iron (Fe $^{2+}$ ), suggesting that the inside of the reactors was reductive to some extent. Electron energy-loss spectroscopy also confirmed that the CsMPs did not contain boron, and therefore the atmosphere in which they were formed might be boron-free.

Journal Articles

Quasielastic neutron scattering of brucite to analyse hydrogen transport on the atomic scale

Okuchi, Takuo*; Tomioka, Naotaka*; Purevjav, N.*; Shibata, Kaoru

Journal of Applied Crystallography, 51, p.1564 - 1570, 2018/12

AA2018-0399.pdf:1.07MB

https://doi.org/10.1107/S1600576718013158

Times Cited Count：2 Percentile：20.7(Chemistry, Multidisciplinary)

It is demonstrated that quasielastic neutron scattering (QENS) is a novel and effective method to analyse atomic scale hydrogen transport processes occurring within a mineral crystal lattice. The method was previously characterized as sensitive for analysing the transport frequency and distance of highly diffusive hydrogen atoms or water molecules in condensed matter. Here are shown the results of its application to analyse the transport of much slower hydrogen atoms which are bonded into a crystal lattice as hydroxyls. Two types of hydrogen transport process were observed in brucite, Mg(OH) $_{2}$ : a jump within a single two-dimensional layer of the hydrogen lattice and a jump into the next nearest layer of it. These transport processes observed within the prototypical structure of brucite have direct implications for hydrogen transport phenomena occurring within various types of oxides and minerals having layered structures.