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Journal Articles

Practical measurement of residual stresses using contour method

Ikushima, Kazuki*; Shibahara, Masakazu*; Kawajiri, Yoshitaka*; Okimi, Yui*; Uchida, Tomoki*; Akita, Koichi*; Suzuki, Hiroshi; Morooka, Satoshi

Nihon Senpaku Kaiyo Kogakkai Rombunshu, (30), p.123 - 130, 2019/12

In this research, the contour method was applied to measure the residual stress distribution of a bead-on-plate specimen. The measured residual stress distribution was compared with those measured by neutron diffraction method and calculated by thermal elastic plastic finite element analysis. As a result, it was found that the residual stress distribution obtained by these three methods are in good agreement. In addition, the equilibrium of reaction force on cut plane was considered in the contour method to measure residual stresses in asymmetric cutting which is assumed in the measurement of real structures. The proposed method was applied to the measurement of the residual stress in the multi-pass welded joint. The measured results indicated that the proposed method can measure the residual stress distribution in multi-pass welded joint in asymmetric test specimen.

Journal Articles

Improvement of plant reliability based on combining of prediction and inspection of crack growth due to intergranular stress corrosion cracking

Uchida, Shunsuke; Chimi, Yasuhiro; Kasahara, Shigeki; Hanawa, Satoshi; Okada, Hidetoshi*; Naito, Masanori*; Kojima, Masayoshi*; Kikura, Hiroshige*; Lister, D. H.*

Nuclear Engineering and Design, 341, p.112 - 123, 2019/01

 Times Cited Count:4 Percentile:56.51(Nuclear Science & Technology)

Improvement of plant reliability based on reliability-centered-maintenance (RCM) is going to be undertaken in NPPs. RCM is supported by risk-based maintenance (RBM). The combination of prediction and inspection is one of the key issues to promote RBM. Early prediction of IGSCC occurrence and its propagation should be confirmed throughout the entire plant systems which should be accomplished by inspections at the target locations followed by timely application of suitable countermeasures. From the inspections, accumulated data will be applied to confirm the accuracy of the code, to tune some uncertainties of the key data for prediction, and then, to increase their accuracy. The synergetic effects of prediction and inspection on application of effective and suitable countermeasures are expected. In the paper, the procedures for the combination of prediction and inspection are introduced.

Journal Articles

Convergence behavior in line profile analysis using convolutional multiple whole-profile software

Kumagai, Masayoshi*; Uchida, Tomohiro*; Murasawa, Kodai*; Takamura, Masato*; Ikeda, Yoshimasa*; Suzuki, Hiroshi; Otake, Yoshie*; Hama, Takayuki*; Suzuki, Shinsuke*

Materials Research Proceedings, Vol.6, p.57 - 62, 2018/10

 Times Cited Count:0 Percentile:0.2

Journal Articles

Off-gas processing system operations for mercury target vessel replacement at J-PARC

Kai, Tetsuya; Uchida, Toshitsugu; Kinoshita, Hidetaka; Seki, Masakazu; Oi, Motoki; Wakui, Takashi; Haga, Katsuhiro; Kasugai, Yoshimi; Takada, Hiroshi

Journal of Physics; Conference Series, 1021(1), p.012042_1 - 012042_4, 2018/06

 Times Cited Count:0 Percentile:0.11

Journal Articles

Fabrication of neutron optical devices using PBW technique

Sakai, Takuro; Iikura, Hiroshi; Yamada, Naoto*; Sato, Takahiro*; Ishii, Yasuyuki*; Uchida, Masaya*

QST-M-8; QST Takasaki Annual Report 2016, P. 140, 2018/03

Journal Articles

Surface modifications of hydrogen storage alloy by heavy ion beams with keV to MeV irradiation energies

Abe, Hiroshi; Tokuhira, Shinnosuke*; Uchida, Hirohisa*; Oshima, Takeshi

Nuclear Instruments and Methods in Physics Research B, 365(Part A), p.214 - 217, 2015/12

no abstracts in English

Journal Articles

Ion induced modifications of Mn-doped ZnO films

Matsunami, Noriaki*; Ito, M.*; Kato, M.*; Okayasu, Satoru; Sataka, Masao*; Kakiuchida, Hiroshi*

Nuclear Instruments and Methods in Physics Research B, 365(Part A), p.191 - 195, 2015/12

 Times Cited Count:6 Percentile:51.48(Instruments & Instrumentation)

We have studied ion impact effects on atomic structure in terms of X-ray diffraction (XRD), optical absorption and electrical resistivity of Mn (6%)-doped ZnO films under 100 MeV Xe ion impact at room temperature. We find the monotonic reduction of the XRD intensity to 1/50 of that of unirradiated film at 5 $$times$$10$$^{14}$$ cm$$^{-2}$$, little bandgap change ($$<$$0.02 eV) and decrease of the resistivity by 4 order of magnitude. The resistivity modification has been compared with that by irradiations of low energy ions such as 100 keV Ne and N, which show more effective decrease of resistivity. We also find that temperature (T) dependence of the magnetic susceptibility ($$chi$$) of Mn-doped ZnO follows the Curie law: $$chi$$ = $$chi$$$$_{o}$$ + C/T (i.e., paramagnetic) and the Curie constant C decreases to a half of that before irradiation (C$$_{O}$$ = 0.012 emu cm$$^{-3}$$ K) at 100 MeV Xe ion fluence of 10$$^{12}$$ cm$$^{-2}$$.

Journal Articles

Surface modification effects on hydrogen absorption property of a hydrogen storage alloy by short pulse laser irradiation

Abe, Hiroshi; Shimomura, Takuya; Tokuhira, Shinnosuke*; Shimada, Yukihiro*; Takenaka, Yusuke*; Furuyama, Yuta*; Nishimura, Akihiko; Uchida, Hirohisa*; Daido, Hiroyuki; Oshima, Takeshi

Proceedings of 7th International Congress on Laser Advanced Materials Processing (LAMP 2015) (Internet), 4 Pages, 2015/08

A short pulse laser (the nanosecond and femtosecond) was applied to hydrogen absorbing alloys surface layer, and a surface modification experiment was put into effective to aim at improvement of hydrogen adsorption functionally. It was investigated about correlation between an initial hydrogen absorption reaction rate of hydrogen alloys and a laser irradiation in this research. The laser irradiation condition was done with pulse width 100 fsec and energy 0.2 - 3.4 mJ/pulse. It blazed down on hydrogen absorbing alloys (LaNi$$_{4.6}$$Al$$_{0.4}$$) and changed local order in the surface. As a result, the initial hydrogen absorption reaction rate was 1.5 - 3.0 times as fast as a irradiated sample, and the result and laser irradiated sample found out that a hydrogen absorption function improves. A laser irradiation can conclude to be effective in surface modification of the hydrogen storage materials.

Journal Articles

Spin-current injection and detection in $$kappa$$-(BEDT-TTF)$$_{2}$$Cu[N(CN)$$_{2}$$]Br

Qiu, Z.*; Uruichi, Mikio*; Hou, D.*; Uchida, Kenichi*; Yamamoto, Hiroshi*; Saito, Eiji

AIP Advances (Internet), 5(5), p.057167_1 - 057167_7, 2015/05

 Times Cited Count:15 Percentile:59.21(Nanoscience & Nanotechnology)

Journal Articles

Periodical public opinion survey on nuclear energy; Inhabitants living Tokyo metropolitan area

Shinoda, Yoshihiko; Tsuchida, Shoji*; Kimura, Hiroshi*

Nihon Genshiryoku Gakkai Wabun Rombunshi, 13(3), p.94 - 112, 2014/09

Fukushima Daiichi Nuclear Power Plant accident (Fukushima accident) has brought about a great change in many people's perceptions about nuclear power plant safety. When discussing future energy options for Japan, it is important to have a full grasp of the attitude of a large number of people towards nuclear energy. The Atomic Energy Society of Japan has conducted annual questionnaire survey of 500 adults who live within 30 kilometers of Tokyo Station. The aim of this survey is to assess trends in public attitude towards nuclear energy. The authors that designed the questionnaire entries of this survey have been managing questionnaire data as members of the Data Management Working Group under the Social and Environmental Division of the Atomic Energy Society of Japan. We confirmed the change in public attitude towards nuclear energy through this periodical survey after the Fukushima accident. In particular, public concerns about the use of nuclear energy increased after the Fukushima accident, and many people have raised doubts over the use of nuclear energy in the future.

Journal Articles

HCM12A Cr-rich oxide layer investigation using 3D atom probe

Kikuchi, Kenji*; Okada, Noriyuki*; Kato, Mikio*; Uchida, Hiroshi*; Saito, Shigeru

Journal of Nuclear Materials, 450(1-3), p.237 - 243, 2014/07

 Times Cited Count:3 Percentile:26.91(Materials Science, Multidisciplinary)

Three-dimensional atom probe techniques were applied to the investigation on the oxide scale in 12Cr ferritic-martensitic steel, HCM12A. A duplex oxide scale was formed in lead bismuth eutectic at 450-500$$^{circ}$$C, during 5500 h. Samples were located 500-700 nm away from the boundary between magnetite and Fe-Cr spinel layers, while the total oxide layer thickness is 18 $$mu$$m. It detected super enrichment of Cr with a size of ten nm roughly, as well as depletion of Fe and enrichment of O at the same site. Surrounding the Cr super enrichment area, enrichment of Si was newly noticed due to the scanned profile of detected atom counts. It is also confirmed that Pb and Bi concentration in the observed spinel region is almost null or less than 0.01 atomic percent, which is possible detecting lowest limit.

Journal Articles

Synergic effects of ion irradiations (La, Ce) and alkaline pretreatment (KOH) on hydriding kinetic property of a Mm-Ni based alloy

Abe, Hiroshi; Aone, Shigeo*; Morimoto, Ryo*; Uchida, Hirohisa*

Journal of Alloys and Compounds, 580(Suppl.1), p.S219 - S221, 2013/12

 Times Cited Count:5 Percentile:34.65(Chemistry, Physical)

no abstracts in English

Journal Articles

Static tensile deformation behavior of a lean duplex stainless steel studied by in situ neutron diffraction and synchrotron radiation white X-rays

Tsuchida, Noriyuki*; Kawahata, Takuji*; Ishimaru, Eiichiro*; Takahashi, Akihiko*; Suzuki, Hiroshi; Shobu, Takahisa

ISIJ International, 53(7), p.1260 - 1267, 2013/07

 Times Cited Count:19 Percentile:71.13(Metallurgy & Metallurgical Engineering)

To investigate the tensile deformation behavior of a lean duplex stainless steel (S32101) from the viewpoints of plastic deformability among phases or grains, we performed static tensile tests, in situ neutron diffraction, and white X-ray diffraction experiments at room temperature. From the experimental results of synchrotron radiation white X-ray diffraction experiments, the hard phase of S32101 was changed from the ferrite phase to austenite one during tensile deformation. This led to a larger stress partitioning between the phases at the latter stage of deformation. From the experimental results of in situ neutron diffraction, it was found that the stress partitioning of the $$gamma$$ phase in the S32101 was the largest among the present results. Therefore, the larger work hardening rate of S32101 can be explained by the large stress partitioning of the $$gamma$$ phase, that between $$gamma$$ and $$alpha$$ phases and $$gamma$$ volume fraction.

Journal Articles

Effects of ultra-intense laser driven proton beam on the hydriding property of palladium

Abe, Hiroshi; Orimo, Satoshi; Kishimoto, Masahiko*; Aone, Shigeo*; Uchida, Hirohisa*; Daido, Hiroyuki; Oshima, Takeshi

Nuclear Instruments and Methods in Physics Research B, 307, p.218 - 220, 2013/07

 Times Cited Count:1 Percentile:12.28(Instruments & Instrumentation)

We investigated the structure changes of a hydrogen storage alloy by ion irradiations, and its absorption property in order to obtain basic data and to elucidate relevant mechanisms of hydrogen absorption by the influence of the irradiation. In previous studies, the induction of vacancies in a hydrogen absorption alloy was found to be effective to increase in the hydrogen absorption rate. As well known, the rate of hydrogen absorption strongly depends upon the surface state of a hydrogen storage alloy because the dissociation of hydrogen molecules or water molecules needs electron change with the surface in the H$$_{2}$$ gas or electrochemical reaction process. In this study, ion irradiations were made at a room temperature using the laser driven proton beam method, at Kansai Photon Science Institute, Japan Atomic Energy Agency. The beam treatment has several unique properties such as short pulse duration, high peak current, low transverse emittance, and wide energy range from KeV to MeV. The irradiation was used to modify the alloy surface using this equipment. From obtained results, the initial hydrogen absorption rate was found improved by the laser driven proton beam rather more effectively than a mono-energetic proton beam. Discussion is made on the correlation among proton irradiation (laser driven proton or mono-energetic proton) and the initial hydrogen absorption rate of the alloy. We argue about the usefulness of an energy spread beam.

Journal Articles

Local structure analysis of SmFe$$_2$$ and TbFe$$_2$$

Yoneda, Yasuhiro; Kohara, Shinji*; Ito, Masayoshi*; Abe, Hiroshi; Takeuchi, Mitsuaki*; Uchida, Hirohisa*; Matsumura, Yoshihito*

Transactions of the Materials Research Society of Japan, 38(1), p.109 - 112, 2013/03

We performed local structure analysis of SmFe$$_2$$ and TbFe$$_2$$ in the crystallization process from amorphous by using synchrotron X-ray pair-distribution function (PDF) method. The giant mangetostrictive materials of these compounds can be controlled its property by ion irradiation. In amorphous TbFe$$_2$$ and SmFe$$_2$$, the mosaic block size was small and the short-range order structure owing to Fe-Fe network maintained. In crystalline SmFe$$_2$$, a rigid long-range order structure of Fe-Fe and Sm-Sm network coexisted and it had a large mosaic block size. On the other hand, in crystalline TbFe$$_2$$, Fe-Fe network degraded by Tb-Tb network owing to its lattice tolerance.

Journal Articles

Managing beryllium in nuclear facility applications

Longhurst, G. R.*; Tsuchiya, Kunihiko; Dorn, C.*; Folkman, S. L.*; Fronk, T. H.*; Ishihara, Masahiro; Kawamura, Hiroshi; Tranter, T. N.*; Rohe, R.*; Uchida, Munenori*; et al.

Nuclear Technology, 176(3), p.430 - 441, 2011/12

 Times Cited Count:4 Percentile:27.67(Nuclear Science & Technology)

Beryllium has important roles in nuclear facilities such as fission reactors and fusion reactors. Its neutron multiplication capability and low atomic weight make it very useful as a reflector in fission reactors. In both applications, the beryllium and the impurities in it become activated by neutrons transmutating to radionuclides, some of which are long-lived and difficult to dispose of. Also, gas production, notably helium and tritium, results in swelling, embrittlement, and cracking, which means that the beryllium must be replaced periodically, especially in fission reactors where dimensional tolerances must be maintained. It has long been known that neutron activation of inherent iron and cobalt in the beryllium results in significant $$^{60}$$Co activity. In 2001, it was discovered that activation of naturally occurring contaminants in the beryllium creates sufficient $$^{14}$$C and $$^{94}$$Nb to render the irradiated beryllium "Greater-Than-Class-C" for disposal in US radioactive waste facilities. In this paper we review the extent of the disposal issue, processes that have been investigated or considered for improving the disposability of irradiated beryllium, and approaches for recycling.

Journal Articles

Identified charged hadron production in $$p + p$$ collisions at $$sqrt{s}$$ = 200 and 62.4 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06

 Times Cited Count:164 Percentile:99.44(Physics, Nuclear)

Transverse momentum distributions and yields for $$pi^{pm}, K^{pm}, p$$, and $$bar{p}$$ in $$p + p$$ collisions at $$sqrt{s}$$ = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different $$sqrt{s}$$ collisions. We also present the scaling properties such as $$m_T$$ and $$x_T$$ scaling and discuss the mechanism of the particle production in $$p + p$$ collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.

Journal Articles

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in $$p+p$$ and Au+Au collisions at $$sqrt{s_{NN}}$$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

 Times Cited Count:8 Percentile:51.82(Physics, Nuclear)

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled $$p+p$$ collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to $$p+p$$ collisions.

Journal Articles

Improvement of hydrogen absorption characteristics of Pd using irradiation of heavey ions

Abe, Hiroshi; Aone, Shigeo*; Morimoto, Ryo*; Uchida, Hirohisa*; Oshima, Takeshi

Transactions of the Materials Research Society of Japan, 36(1), p.133 - 135, 2011/03

The introduction of vacancies in Pd was found to be effective for an increase in the initial hydrogen absorption rate in a previous study. Also, it was reported that the initial hydrogen absorption rate depends strongly on the surface conditions of metals. Heavy ions with keV ranges can create severe damage and high densities of vacancy near the surface of materials. As well known, the formation of hydride phases can be facilitated by the presence of vacancy because vacancy acts as hydrogen trapping site to form hydrides. Thus, the hydrogen absorption characteristics of Pd may be improved by the irradiation of heavy ions. As a result, the initial hydrogen absorption rate increased due to ion irradiation, and the value became 3$$sim$$10 times higher than un-irradiated Pd.

Journal Articles

Interlayer Josephson couplings in Hg-based multi-layered cuprates

Hirata, Yasuyuki*; Kojima, Kenji*; Uchida, Shinichi*; Ishikado, Motoyuki; Iyo, Akira*; Eisaki, Hiroshi*; Tajima, Setsuko*

Physica C, 470(Suppl.1), p.S44 - S46, 2010/12

 Times Cited Count:2 Percentile:12.71(Physics, Applied)

Infrared reflectivity spectra of the multilayered HgBa$$_{2}$$Ca$$_{n-1}$$Cu$$_{n}$$O$$_{2n+2+delta}$$ (${it n}$ = 2, 3, 4, and 5) are measured. Optical plasma modes associated with the Josephson coupling between CuO$$_{2}$$ planes within a multilayer appear below $$T$$$$_{rm c}$$ in the c-axis component of the reflectivity spectrum. For the bilayer and trilayer compound an optical Josephson plasma mode appears at unprecedentedly high frequency, $$sim$$ 700-800 cm$$^{-1}$$, below $$T$$$$_{rm c}$$. The plasma frequencies appreciably decrease in four- and five-layer compounds which indicates the suppression of superconducting order in the inner CuO$$_{2}$$ planes, consistent with the result of NMR experiment.

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