Visualisation and quantitative evaluation of chlorides in corroded crevice of stainless steel using radioisotope Cl

Aoki, So; Abe, Yosuke; Abe, Hiroshi*; Watanabe, Yutaka*; Yamamoto, Masahiro*

Corrosion Science, 255, p.113119_1 - 113119_10, 2025/10

https://doi.org/10.1016/j.corsci.2025.113119

This study aimed to visualise the distribution of chloride in the corroded crevice of stainless steel and to evaluate the chloride content quantitatively. Crevice corrosion tests were carried out using Cl, a radioactive isotope of chloride, as a tracer in NaCl test solutions. After crevice corrosion tests, stainless steel specimens were placed on an imaging plate. The imaging plate was sensitised by -ray emitted by Cl adhering to the crevice. As a result, the chloride distribution in the corroded area inside the crevice was visualised. A calibration curve for the amount of Cl was obtained from the relationship between the time of photosensitivity to -ray emitted by Cl and the luminance of the imaging plate. The chloride content in the corroded crevice was quantitatively evaluated based on the calibration curve. These visualisation and quantitative evaluation methods were also applied to tests in which specimens were left in pure water after crevice corrosion tests, and the behaviour of chloride in crevice corrosion was discussed.

Successive phase transitions in the quasi-kagome lattice system URhSn studied by resonant X-ray scattering

Tabata, Chihiro; Kon, Fusako*; Hibino, Ruo*; Shimizu, Yusei*; Amitsuka, Hiroshi*; Kaneko, Koji; Homma, Yoshiya*; Aoki, Dai*; Nakao, Hironori*

Journal of the Physical Society of Japan, 94(8), p.083701_1 - 083701_5, 2025/07

https://doi.org/10.7566/JPSJ.94.083701

Diamond-shaped quantum circuit for real-time quantum dynamics in one dimension

Miyakoshi, Shohei*; Sugimoto, Takanori*; Shirakawa, Tomonori*; Yunoki, Seiji*; Ueda, Hiroshi*

Physical Review Research (Internet), 6(4), p.043318_1 - 043318_14, 2024/12

https://doi.org/10.1103/PhysRevResearch.6.043318

Development of the versatile reactor analysis code system, MARBLE3

Yokoyama, Kenji; Hazama, Taira; Taninaka, Hiroshi; Oki, Shigeo

JAEA-Data/Code 2024-007, 41 Pages, 2024/10

JAEA-Data-Code-2024-007.pdf:1.1MB

The third version of the versatile reactor analysis code system, MARBLE3, has been developed. In the development of the former version of MARBLE, object-oriented scripting language Python (Python2) had been used and then the latest version of Python (Python3) was released. However, due to its backward incompatibility, MARBLE no longer worked with Python3. For this reason, MARBLE3 has been fully modified and maintained to work with Python3. In MARBLE3, newly developed analysis codes and newly proposed calculation methods were incorporated, and the user interface was extended and solvers were reimplemented for maintainability, extensibility, and flexibility. In MARBLE3, the three-dimensional hexagonal/triangular transport code MINISTRI Ver.7 (MINISTRI7) and the three-dimensional hexagonal/triangular diffusion code D-MINISTRI are available as the new analysis codes. These codes can be used in the neutronics analysis system SCHEME and the fast reactor burnup analysis system OPRHEUS, which are the subsystems of MARBLE. In addition, the user interface of CBG, a core analysis system embedded in MARBLE, was extended so that the diffusion and transport calculation solvers for the 2-dimensional RZ system of CBG can be used on SCHEME. On the other hand, MARBLE3 has extended the functionality of the burnup calculation solver so that it can use the numerical methods proposed in the papers on the improvement of the Chebyshev rational function approximation method and the minimax polynomial approximation method. From the viewpoint of maintainability, the point reactor kinetics solver POINTKINETICS, which was introduced in MARBLE2, has been newly reworked as the KINETICS solver in MARBLE3.

Model integration of the ex-vessel modules for the SFR safety analysis code SPECTRA

Aoyagi, Mitsuhiro; Makino, Toru*; Oki, Hiroshi*; Uchibori, Akihiro; Okano, Yasushi

Mechanical Engineering Journal (Internet), 11(2), p.23-00459_1 - 23-00459_12, 2024/04

https://doi.org/10.1299/mej.23-00459

Transient analyses of hydraulic head in the fault slip experiments in fracture zones of Shionohira and Kuruma Faults

Wakahama, Hiroshi*; Nojo, Haruka*; Aoki, Kazuhiro; Imai, Hirotaro; Guglielmi, Y.*; Cook, P.*; Soom, F.*

Oyo Chishitsu, 64(5), p.236 - 254, 2023/12

https://doi.org/10.5110/jjseg.64.236

Upon the Hamadori earthquake (Mw 6.7) of 11 April 2011, coseismic surface deformation of 14 km running NNW to SSE in southeast Fukushima Prefecture occurred and was newly named the Shionohira Fault. However, no surface deformation was observed along the Kuruma Fault which is a southern extension of the Shionohira Fault. Fault injection tests using SIMFIP method at the Shionohira site on the former active segment and the Minakamikita site on the latter inactive segment were conducted to evaluate the activity of the two faults. Based on hydraulic responses to water injection into the fault rupture zone in the monitoring boreholes at the two sites, hydraulic properties of the area across the fault zone were estimated using the GRF model (Barker, 1988). The results obtained on hydraulic conductivity, specific storage and flow dimension were consistent with those in the domestic and international literature. The hydraulic conductivity and specific storage were larger in Shionohira than in Minakamikita. The flow dimension of Shionohira was three-dimensional, while that of Minakamikita was found to be a two-dimensional fractional flow. In addition, it is understood that the volumetric expansion occurs in the former site in the triaxial direction and the latter in the uniaxial with the comparison between the uniaxial expansion coefficient calculated from the results of SIMFIP displacement measurements and the specific storage in the hydraulic analysis. The difference in the hydraulic parameters between the two sites corresponded to the difference in the spatial development of fractures considered to be the "water passway," indicating the possibility of a correlation between the parameters and the different possible causes for fault activity at the two sites.

Analytical investigation of multidimensional effects of sodium spray combustion experiments

Sonehara, Masateru; Okano, Yasushi; Uchibori, Akihiro; Aoyagi, Mitsuhiro; Oki, Hiroshi*

Dai-27-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu (Internet), 4 Pages, 2023/09

https://doi.org/10.1299/jsmepes.2023.27.A131

An analysis code AQUA-SF has been developed to evaluate the effects of sodium combustion in three dimensions, which enables more detailed elucidation of sodium combustion phenomena and evaluation of the effectiveness of safety measures. In this paper, we examine the multidimensional effects of spray combustion for the SNL-T3 test as a benchmark analysis. In order to simulate the decrease of pressure and the temperature rise near the floor during the test, a new model is developed to take into account temporal cessation of sodium ignition, increased drag coefficient due to droplet deformation and liquid splash effect due to collision between the jet stream and the floor surface, and the results are compared with the test measurements.

On-site training using JMTR and related facilities in FY2019

Nakano, Hiroko; Nishikata, Kaori; Nagata, Hiroshi; Ide, Hiroshi; Hanakawa, Hiroki; Kusunoki, Tsuyoshi

JAEA-Review 2022-073, 23 Pages, 2023/01

JAEA-Review-2022-073.pdf:2.02MB

A practical training course using the JMTR (Japan Materials Testing Reactor) and other research infrastructures was held from July 24th to July 31st in 2019 for Asian young researchers and engineers. This course was adopted as Japan-Asia Youth Exchange Program in Science (SAKURA Exchange Program in Science) which is the project of the Japan Science and Technology Agency, and this course aims to enlarge the number of high-level nuclear researchers/engineers in Asian countries which are planning to introduce a nuclear power plant, and to promote the use of facilities in future. In this year, 12 young researchers and engineers joined the course from 6 countries. This course consists of lectures, which are related to irradiation test research, safety management of nuclear reactors, nuclear characteristics of the nuclear reactors, etc., practical training such as practice of research reactor operation using simulator and technical tour of nuclear facilities on nuclear energy. The content of this course in FY 2019 is reported in this paper.

Neutron reflectivity study on the suppression of interfacial water accumulation between a polypropylene thin film and Si substrate using a silane-coupling agent

Shimokita, Keisuke*; Yamamoto, Katsuhiro*; Miyata, Noboru*; Arima-Osonoi, Hiroshi*; Nakanishi, Yohei*; Takenaka, Mikihito*; Shibata, Motoki*; Yamada, Norifumi*; Seto, Hideki*; Aoki, Hiroyuki; et al.

Langmuir, 38(41), p.12457 - 12465, 2022/10

https://doi.org/10.1021/acs.langmuir.2c01599

Sodium-cooled Fast Reactors

Ohshima, Hiroyuki; Morishita, Masaki*; Aizawa, Kosuke; Ando, Masanori; Ashida, Takashi; Chikazawa, Yoshitaka; Doda, Norihiro; Enuma, Yasuhiro; Ezure, Toshiki; Fukano, Yoshitaka; et al.

Sodium-cooled Fast Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.3, 631 Pages, 2022/07

https://shop.elsevier.com/books/sodium-cooled-fast-reactors/morishita/978-0-12-824076-2

This book is a collection of the past experience of design, construction, and operation of two reactors, the latest knowledge and technology for SFR designs, and the future prospects of SFR development in Japan. It is intended to provide the perspective and the relevant knowledge to enable readers to become more familiar with SFR technology.