Development of a non-destructive depth-selective quantification method for sub-percent carbon contents in steel using negative muon lifetime analysis

Ninomiya, Kazuhiko*; Kubo, Kenya*; Inagaki, Makoto*; Yoshida, Go*; Chiu, I.-H. ; Kudo, Takuto*; Asari, Shunsuke*; Sentoku, Sawako*; Takeshita, Soshi*; Shimomura, Koichiro*; et al.

Scientific Reports (Internet), 14, p.1797_1 - 1797_8, 2024/01

https://doi.org/10.1038/s41598-024-52255-5

The amount of C in steel, which is critical in determining its properties, is strongly influenced by steel production technology. We propose a novel method of quantifying the bulk C content in steel non-destructively using muons. This revolutionary method may be used not only in the quality control of steel in production, but also in analyzing precious steel archaeological artifacts. A negatively charged muon forms an atomic system owing to its negative charge, and is finally absorbed into the nucleus or decays to an electron. The lifetimes of muons differ significantly, depending on whether they are trapped by Fe or C atoms, and identifying the elemental content at the muon stoppage position is possible via muon lifetime measurements. The relationship between the muon capture probabilities of C/Fe and the elemental content of C exhibits a good linearity, and the C content in the steel may be quantitatively determined via muon lifetime measurements. Furthermore, by controlling the incident energies of the muons, they may be stopped in each layer of a stacked sample consisting of three types of steel plates with thicknesses of 0.5 mm, and we successfully determined the C contents in the range 0.20 - 1.03 wt% depth-selectively, without sample destruction.

Characterization of phosphate cement irradiated by -ray during dehydration

Irisawa, Keita; Kudo, Isamu*; Taniguchi, Takumi; Namiki, Masahiro*; Osugi, Takeshi; Nakazawa, Osamu

QST-M-8; QST Takasaki Annual Report 2016, P. 63, 2018/03

https://repo.qst.go.jp/records/73811

A solidification technique with minimized water content is being developed using a phosphate cement for safe storage of secondary radioactive wastes in the Fukushima Daiichi Nuclear Power Plant. To understand the applicability of the solidification technique for the actual secondary wastes, phosphate cement during dehydration was irradiated by Co -ray. The G(H) for the phosphate cement decreased with time during dehydration, and was not detected after 7 days. Moreover, the Co -ray irradiation during dehydration did not change the crystalline and amorphous phases of the phosphate cement.

Gas control measures taken during deep shaft excavation

Nago, Makito*; Hagihara, Takeshi*; Minamide, Masashi*; Motoshima, Takayuki*; Jin, Kazumi; Kudo, Hajime; Sugita, Yutaka; Miura, Yoichi*

Dai-49-Kai Zenkoku Kensetsugyo Rodo Saigai Boshi Taikai Kenkyu Rombunshu (CD-ROM), p.77 - 80, 2012/10

This paper presents measures against gas emission during deep shaft excavation in the Horonobe Underground Research Laboratory Project (Horonobe URL Project). The gas control measures taken in the Horonobe URL Project include the following: (1) determination of the amount of methane contained in surrounding strata and groundwater, and gas concentration based on preliminary investigations, (2) determination of the specifications of fans, dust collectors, and ducts through ventilation network analysis (simulation), (3) reduction of methane gas emission through the use of waterproofing grout, (4) prohibition on the use of internal-combustion engine and the adoption of explosion-proof equipment, (5) development of methane gas control system, and (6) monitoring of methane gas emission. (3) to (6) described above are performed daily in the safety management activities and described in detail in this paper. The ventilation and eastern access shafts have currently reached a depth of 290 m and 250 m, respectively. The emission of methane gas has been observed to rise 0.3 % to 1.3 % in the fault zone, and it is controlled appropriately according to the gas control measures described above. As the measure to reduce the methane gas concentration, monitoring is confirmed to be effective.

Development of function-graded proton exchange membrane for PEFC using heavy ion beam irradiation

Shiraki, Fumiya*; Yoshikawa, Taeko*; Oshima, Akihiro*; Oshima, Yuji*; Takasawa, Yuya*; Fukutake, Naoyuki*; Oyama, Tomoko*; Urakawa, Tatsuya*; Fujita, Hajime*; Takahashi, Tomohiro*; et al.

Nuclear Instruments and Methods in Physics Research B, 269(15), p.1777 - 1781, 2011/08

https://doi.org/10.1016/j.nimb.2011.04.117

The graded energy deposition of heavy ion beam irradiation to polymeric materials was utilized to synthesize a novel proton exchange membrane (PEM) with the graded density of sulfonic acid groups toward the thickness direction. Stacked Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were irradiated by Xe ion beam with the energy of 6 MeV/u under a vacuum condition. Irradiated films were grafted with styrene monomer and then sulfonated. The membrane electrode assembly (MEA) fabricated by the function graded PEM showed improved fuel cell performance in terms of voltage stability. It was expected that the function-graded PEM could control the graded concentration of sulfonic acid groups in PEM.

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.

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

http://accelconf.web.cern.ch/AccelConf/IPAC10/papers/tupe091.pdf

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Variations of gravity anomaly roughness in Chugoku district, Japan: Relationship with distributions of topographic lineaments

Kudo, Takeshi; Yamamoto, Akihiko*; Nohara, Tsuyoshi; Kinoshita, Hirohisa; Shichi, Ryuichi*

Earth Planets and Space, 56(5), p.e5 - e8, 2004/00

https://doi.org/10.1186/BF03352505

We investigate whether distributions of topographic lineaments in Chugoku district, Japan, may be related to variations of standard deviation (SD) of gravity anomalies. Tectonic movement may disturb lateral continuities of crustal structures at weak zones. These lateral discontinuities of the density structure cause undulations of gravity anomaly fields whose complexities can be an indicator of the past crustal instability. On the other hand, topographic lineaments are formed along weak crustal zones. We would expect therefore that the gravity anomaly complexities have some relations to distributions of surface lineaments. As an index of gravity anomaly complexities in terms of which we interpret spatial distribution of topographic lineaments, we employ Bouguer anomaly SD inside a circular region with adequate radius. The results show that locations of the lineaments, which could be diagnostic of heterogeneity of the previously damaged crust, tend to coincide with those of high SD area

Study on Microbial Influence Assessment in Geological Disposal (II) (Summary Report)

Fukunaga, Sakae*; Iwata, Yumiko*; Kanno, Takeshi*; Kudo, Akira*

JNC TJ8400 2003-070, 45 Pages, 2003/02

JNC-TJ8400-2003-070.pdf:0.13MB

This report summarizes two investigations concerned with microbial influence in geological disposal facilities. 1)Literature survey on simulation models for the microbial-influence evaluation, 2) Experiment for the interaction between bacteria and Pu at Eh=-135mV.

Variations of Standard Deviation of Gravity Anomalies in Chugoku District, Japan - Relationship with Distributions of Topographic Lineaments -

Kudo, Takeshi; Nohara, Tsuyoshi; Kinoshita, Hirohisa; Yamamoto, Akihiko*; Shichi, Ryuichi*

American Geophysical Union 2003 Fall Meeting, P. F1428, 2003/00

Relationship between distributions of topographic lineaments and variations of standard deviation of gravity anomalies in Chugoku district, Japan is investigated. Tectonic movement may disturb lateral continuities of crustal structures at weak zones. Lateral discontinuities of the density structure cause undulations of gravity anomaly field over them. Therefore, complexities of the gravity anomaly field might be an indicator of the past crustal instability. On the other hand, topographic lineaments are formed along zones of inherent crustal weakness. Therefore, the gravity anomaly complexities should have some relations to distributions of surface lineaments. In order to verify this conjecture, we investigated gravity anomaly complexities in relation to the spatial distributions of topographic lineaments.

Operation of circular dichroism measurements with periodic photon-helicity switching by an APPLE-2 type undulator at BL23SU at SPring-8

Agui, Akane; Yoshigoe, Akitaka; Nakatani, Takeshi; Matsushita, Tomohiro*; Saito, Yuji; Mizumaki, Masaichiro*; Yokoya, Akinari; Tanaka, Hitoshi*; Miyahara, Yoshikazu*; Shimada, Taihei; et al.

Hoshako, 14(5), p.339 - 348, 2001/11

http://ci.nii.ac.jp/naid/10007157437

no abstracts in English