Neutron reflectivity study on the nanostructure of PMMA chains near substrate interfaces based on contrast variation accompanied with small molecule sorption

Shimokita, Keisuke*; Yamamoto, Katsuhiro*; Miyata, Noboru*; Nakanishi, Yohei*; Shibata, Motoki*; Takenaka, Mikihito*; Yamada, Norifumi*; Seto, Hideki*; Aoki, Hiroyuki; Miyazaki, Tsukasa*

Soft Matter, 19(11), p.2082 - 2089, 2023/03

https://doi.org/10.1039/D2SM01482C

Neutron reflectometry-based structural analysis of an aligning agent additive for the alignment of nematic liquid crystals on solid substrates

Nemoto, Fumiya*; Yamada, Norifumi*; Hino, Masahiro*; Aoki, Hiroyuki; Seto, Hideki*

Soft Matter, 18(3), p.545 - 553, 2022/01

https://doi.org/10.1039/D1SM01355F

Design and performance of high-pressure PLANET beamline at pulsed neutron source at J-PARC

Hattori, Takanori; Sano, Asami; Arima, Hiroshi*; Komatsu, Kazuki*; Yamada, Akihiro*; Inamura, Yasuhiro; Nakatani, Takeshi; Seto, Yusuke*; Nagai, Takaya*; Utsumi, Wataru; et al.

Nuclear Instruments and Methods in Physics Research A, 780, p.55 - 67, 2015/04

https://doi.org/10.1016/j.nima.2015.01.059

PLANET is a time-of-flight (ToF) neutron beamline dedicated to high-pressure and high-temperature experiments. The large six-axis multi-anvil high-pressure press designed for ToF neutron diffraction experiments enables routine data collection at high pressures and high temperatures up to 10 GPa and 2000 K, respectively. To obtain clean data, the beamline is equipped with the incident slits and receiving collimators to eliminate parasitic scattering from the high-pressure cell assembly. The high performance of the diffractometer for the resolution ( / 0.6%) and the accessible -spacing range (0.2-8.4 ) together with low-parasitic scattering characteristics enables precise structure determination of crystals and liquids under high pressure and temperature conditions.

Changes to the chemical structure of isotactic-polypropylene induced by ion-beam irradiation

Oka, Toshitaka; Oshima, Akihiro*; Motohashi, Ryota*; Seto, Naoto*; Watanabe, Yuji*; Kobayashi, Ryoji*; Saito, Koki*; Kudo, Hisaaki*; Murakami, Takeshi*; Washio, Masakazu*; et al.

Radiation Physics and Chemistry, 80(2), p.278 - 280, 2011/02

https://doi.org/10.1016/j.radphyschem.2010.07.047

The chemical structures of various ion-beam irradiated isotactic-polypropylene samples were studied. Results of micro-Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy suggest not only the linear energy transfer, but also the fluence is effective in local transformation of the isotactic-polypropylene.

None

; ; *

JNC TY7400 2001-001, 30 Pages, 2001/03

JNC-TY7400-2001-001.pdf:1.24MB

None

Evaluation on strength of reinforced concrete slabs in Bituminization Demonstraion Facility

Yamada, Toshiro*; Morikawa, Hiroshi*; Ishida, Masatoshi*; Seto, Yutaka*; Yamamoto, Yoshifumi*; Sawamoto, Yoshikazu*

JNC TJ8410 98-002, 124 Pages, 1998/11

JNC-TJ8410-98-002.pdf:3.82MB

On the 11st of March 1997, a fire and explosion occurred in a Bituminization Demonstraion Facility. It subsequently became necessary to estimate the explosive force of this event. To this end, this report evaluates the static yield and ultimate strength of the main structural walls and floors of this facility. A simple method and a Finite Element Method (FEM) were considered to evaluate the yield and ultimate strength of reinforced concrete (RC) slabs. Using the simple method, the yield strength can be estimated effectively by solution of fundamental differential equations. The ultimate strength of RC slabs is tried to estimate using a modified yield line theory which is taken an arch effect created within RC slabs into account. However, this method is difficult to apply to slabs with complicated boundary conditions. In this case, FEM is necessary. The validity of the simple method is verified by analyzing some slabs using both methods and comparing the results. Previous experimental results and some RC slabs in the Asphalt Bituminization Facility were evaluated on the basis of yield and ultimate strength using both methods, and the validity of both methods were verified. Especially, in simulating previous experiments, the error in the estimated values of the ultimate strength using simple method to experimental values were within 30%. The estimated values of the ultimate strength using the FEM were 15% larger than the experimental values. As a result, the simple method taking arch effect into account was verified to some extent.

Liquid leakage from the sea release pipe of the Tokai reprocessing plant; Cause investigation of the leakage, 2; Progress from mechanical damage to the leak

Domura, Kazuyuki; Morimoto, Kenji; Seto, Nobuhiko; Iwasaki, Shogo; Fukuari, Yoshihiro; Inami, Shinichi

no journal, , 

A leak occurred from the sea release pipe buried in the bottom of the sea of the Tokai reprocessing plant. The plumbing of the leak point was cut to investigate the cause of the leak and was collected ashore. Then the investigations such as surface observation and other analyses were performed. As a result of this investigation, the plumbing was scratched at the time of construction from the outside. In the service of approximately 17 years, a damaged part changed with age, and it was estimated that it led to a crack. It was estimated for the leak of the plumbing that hydrogen produced with electrolytic protection caused hydrogen embrittlement cracking and hydrogen induced cracking. This paper reports the details of the investigations.

Effects of environmental mitigation and water radiolysis on crack growth in simulated BWR environment in highly irradiated 316L stainless steel

Chimi, Yasuhiro; Kasahara, Shigeki; Hata, Kuniki; Nishiyama, Yutaka; Seto, Hitoshi*; Chatani, Kazuhiro*; Kitsunai, Yuji*; Koshiishi, Masato*

no journal, , 

In order to investigate effects of environmental mitigation and water radiolysis caused by -rays from radioactive material on irradiation-assisted stress corrosion cracking (IASCC) growth behavior for highly irradiated material, crack growth tests in simulated BWR water conditions (at 563 K) are performed. The specimens made of 316L stainless steels are irradiated with neutrons up to 12 dpa in the Japan Materials Testing Reactor (JMTR). One of the specimens is annealed at 973 K for 1 hour to show almost recovered mechanical and micro-chemical properties corresponding to the unirradiated material. For low electrochemical corrosion potential (ECP) condition, the crack growth rate (CGR) is suppressed by about one order of magnitude in high stress intensity factor (K) condition. This result indicates that environmental mitigation for crack growth can be found even under severe conditions on material and stress factors. The effects of water radiolysis on the CGRs are discussed.

Relationship between crack growth rates and locally deformed structures in irradiated 316L stainless steels

Chimi, Yasuhiro; Kasahara, Shigeki; Nishiyama, Yutaka; Seto, Hitoshi*; Kitsunai, Yuji*; Koshiishi, Masato*

no journal, , 

In order to understand irradiation-assisted stress corrosion cracking (IASCC) growth behavior, crack growth tests using compact tension (CT) specimens made of neutron-irradiated 316L stainless steels (SSs) were performed in simulated BWR environments (at 288C). Moreover, microstructures of deformed areas were observed by transmission electron microscope (TEM) after straining tensile specimens made of neutron-irradiated 316L SSs. As a result, for lower neutron dose than 1.9 dpa, the crack growth rates (CGRs) show effective environmental mitigation and the deformed structures show tangling of dislocations. On the other hand, for higher neutron dose than 2.7 dpa, the CGRs show small environmental mitigation and the deformed structures consist mainly of dislocation channels. From the relationship between CGRs and deformed structures, mechanisms on IASCC growth will be discussed.