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Journal Articles

Mechanisms of action of radon therapy on cytokine levels in normal mice and rheumatoid arthritis mouse model

Kataoka, Takahiro*; Naoe, Shota*; Murakami, Kaito*; Yukimine, Ryohei*; Fujimoto, Yuki*; Kanzaki, Norie; Sakoda, Akihiro; Mitsunobu, Fumihiro*; Yamaoka, Kiyonori*

Journal of Clinical Biochemistry and Nutrition, 70(2), p.154 - 159, 2022/03

Journal Articles

Development of HCl-free solid phase extraction combined with ICP-MS/MS for rapid assessment of difficult-to-measure radionuclides, 1; Selective measurement of $$^{93}$$Zr and $$^{93}$$Mo in concrete rubble

Do, V. K.; Furuse, Takahiro; Murakami, Erina; Aita, Rena; Ota, Yuki; Sato, Soichi

Journal of Radioanalytical and Nuclear Chemistry, 327(1), p.543 - 553, 2021/01

 Times Cited Count:0 Percentile:0.01(Chemistry, Analytical)

A new HCl-free chromatographic separation procedure has been developed for sequential separation of Zr and Mo from concrete matrices. Accordingly, $$^{93}$$Zr and $$^{93}$$Mo could be sensitively and selectively measured by ICP-MS/MS using ammonia reaction gas. The recoveries of greater than 90% for Zr and Mo from concretes could be achieved. The measurement condition was optimized for complete suppression of interferences from $$^{93}$$Nb and peak tailing from abundant isotopes of Zr and Mo in concrete matrices. The removal of interferences was verified by measurement of radio-contamination-free concretes used as a sample matrix blank. Method detection limits of 1.7 mBq g$$^{-1}$$ and 0.2 Bq g$$^{-1}$$ were achieved for $$^{93}$$Zr and $$^{93}$$Mo, respectively, in the concrete matrices. The interference removal factor for Nb (equivalent to the decontamination factor in radiochemical separation) was of the order of 10$$^{5}$$, and the abundance sensitivity was of the order of 10$$^{-8}$$, indicating that the developed method is reliable for verifying the presence of ultralow concentrations of $$^{93}$$Zr and $$^{93}$$Mo. The present method is suitable for the rapid assessment of $$^{93}$$Zr and $$^{93}$$Mo for radioactivity inventory of concrete rubble.

Journal Articles

Thermal fluid activities along the Mozumi-Sukenobu fault, central Japan, identified via zircon fission-track thermochronometry

Sueoka, Shigeru; Ikuho, Zuitetsu*; Hasebe, Noriko*; Murakami, Masaki*; Yamada, Ryuji*; Tamura, Akihiro*; Arai, Shoji*; Tagami, Takahiro*

Journal of Asian Earth Sciences; X (Internet), 2, p.100011_1 - 100011_11, 2019/11

no abstracts in English

Journal Articles

Application of analysis for assembly of integrated components to steel member connections towards seismic safety assessment of plant structures

Nishida, Akemi; Murakami, Takahiro*; Satoda, Akira*; Asano, Yuya*; Guo, Z.*; Matsukawa, Keisuke*; Oshima, Masami*; Nakajima, Norihiro

Proceedings of 25th International Conference on Structural Mechanics in Reactor Technology (SMiRT-25) (USB Flash Drive), 10 Pages, 2019/08

Exhaustive studies on external events that may pose a threat to the structures of nuclear facilities and evaluations of the structural integrities are critical to safety. One of the components that greatly influence the behavior of the plant structure is the connection of structural members. In particular, the modeling of the connections has relied on empirical methods, and been conservatively designed and evaluated by considering them as pinned or rigid connections. Therefore, in this research, we have aimed to develop a connection modeling method that reproduces more realistic behavior by utilizing a three-dimensional model of the connection. As the first step of this research, we planned to determine the stiffness of the connections of steel structural members. The results confirmed that the connection can be regarded as a partially-restrained connection depending on the connection specifications of the structure, and the prospects for realistic stiffness evaluation of the connection were determined.

Journal Articles

Onsite chelate resin solid-phase extraction of rare earth elements in natural water samples; Its implication for studying past redox changes by inorganic geochemistry

Watanabe, Takahiro; Kokubu, Yoko; Murakami, Hiroaki; Iwatsuki, Teruki

Limnology, 19(1), p.21 - 30, 2018/01

 Times Cited Count:8 Percentile:63.89(Limnology)

Rare earth element (REE) patterns in natural water and geological samples provides information on changes in past environmental conditions, such as redox changes and material cycles; however, quantitative analysis of REEs in these samples is complicated because of relative low content and mass interference from barium oxide in the inductively coupled plasma mass spectrometry (ICP-MS) analyses. In this study, we adopted onsite solid-phase extraction and preconcentration methods for REEs using an iminobisacetic acid-ethylenediaminetriacetic acid chelate resin for the analyses. Standard reference materials, natural ground water, and spring water samples were used for the evaluation of these methods. The REE patterns in the natural water samples were in good agreement with those obtained using previous methods. Therefore, it was deduced that onsite solid-phase extraction using chelate resin is a rapid and simple preparation technique for REE analyses.

Journal Articles

Development of an evaluation methodology for the natural circulation decay heat removal system in a sodium cooled fast reactor

Watanabe, Osamu*; Oyama, Kazuhiro*; Endo, Junji*; Doda, Norihiro; Ono, Ayako; Kamide, Hideki; Murakami, Takahiro*; Eguchi, Yuzuru*

Journal of Nuclear Science and Technology, 52(9), p.1102 - 1121, 2015/09

 Times Cited Count:11 Percentile:73.32(Nuclear Science & Technology)

A natural circulation (NC) evaluation methodology has been developed to ensure the safety of a sodium-cooled fast reactor (SFR) of 1500MW adopting the NC decay heat removal system (DHRS). The methodology consists of a 1D safety analysis which can evaluate the core hot spot temperature taking into account the temperature flattening effect in the core, a 3D fluid flow analysis which can evaluate the thermal-hydraulics for local convections and thermal stratifications in the primary system and DHRS, and a statistical safety evaluation method. The safety analysis method and the 3D analysis method have been validated using results of a 1/10 scaled water test simulating the primary system of the SFR and a 1/7 scaled sodium test simulating the primary system and the DHRS, and the applicability of the safety analysis for the SFR has been confirmed by comparing with the 3D analysis. Finally, a statistical safety evaluation has been performed for the SFR using the safety analysis method.

Journal Articles

Development of advanced inductive scenarios for ITER

Luce, T. C.*; Challis, C. D.*; Ide, Shunsuke; Joffrin, E.*; Kamada, Yutaka; Politzer, P. A.*; Schweinzer, J.*; Sips, A. C. C.*; Stober, J.*; Giruzzi, G.*; et al.

Nuclear Fusion, 54(1), p.013015_1 - 013015_15, 2013/12

 Times Cited Count:23 Percentile:80.5(Physics, Fluids & Plasmas)

Journal Articles

Development of proposed guideline of flow-induced vibration evaluation for hot-leg piping in a sodium-cooled fast reactor

Sakai, Takaaki; Yamano, Hidemasa; Tanaka, Masaaki; Ono, Ayako; Ohshima, Hiroyuki; Kaneko, Tetsuya*; Hirota, Kazuo*; Sago, Hiromi*; Xu, Y.*; Iwamoto, Yukiharu*; et al.

Proceedings of 15th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-15) (USB Flash Drive), 13 Pages, 2013/05

The development of flow-induced vibration evaluation methodology has reached a milestone that separate-effect experimental data under a high Reynolds number regime including swirl and deflected inflow conditions are available for the validation of the methodology. On the other hand, technical standards are desirable to be documented for designers of sodium-cooled fast reactors. From such a background, the documentation of a flow-induced vibration design guideline has been made for the hot-leg piping of Japan sodium-cooled fast reactor. This paper describes the design guideline of the flow-induced vibration evaluation methodology, which has been informed from main separate-effect experiments, as well as supplemental interpretation for the guideline.

Journal Articles

New result in the production and decay of an isotope, $$^{278}$$113 of the 113th element

Morita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Haba, Hiromitsu*; Ozeki, Kazutaka*; Kudo, Yuki*; Sumita, Takayuki*; Wakabayashi, Yasuo*; Yoneda, Akira*; Tanaka, Kengo*; et al.

Journal of the Physical Society of Japan, 81(10), p.103201_1 - 103201_4, 2012/10

 Times Cited Count:142 Percentile:97.35(Physics, Multidisciplinary)

An isotope of the 113th element, $$^{278}$$113, was produced in a nuclear reaction with a $$^{70}$$Zn beam on a $$^{209}$$Bi target. We observed six consecutive $$alpha$$ decays following the implantation of a heavy particle in nearly the same position in the semiconductor detector, in extremely low background condition. The fifth and sixth decays are fully consistent with the sequential decays of $$^{262}$$Db and $$^{258}$$Lr both in decay energies and decay times. This indicates that the present decay chain consisted of $$^{278}$$113, $$^{274}$$Rg (Z = 111), $$^{270}$$Mt (Z = 109), $$^{266}$$Bh (Z = 107), $$^{262}$$Db (Z = 105), and $$^{258}$$Lr (Z = 103) with firm connections. This result, together with previously reported results from 2004 and 2007, conclusively leads the unambiguous production and identification of the isotope $$^{278}$$113, of the 113th element.

Journal Articles

Study on mechanism of pressure fluctuation in a primary circuit hot-leg pipings of a sodium-cooled fast reactor

Murakami, Takahiro*; Eguchi, Yuzuru*; Tanaka, Masaaki; Yamano, Hidemasa

Nihon Kikai Gakkai Rombunshu, B, 78(792), p.1388 - 1391, 2012/08

In a conceptual design of Japan Sodium-cooled Fast Reactor (JSFR), short-elbow pipings with large-diameter are adopted for cooling system, in which the coolant flow causes periodical pressure fluctuation at the short-elbow. However, the mechanism of the periodical pressure fluctuation has not been clarified yet. In this paper, unsteady three-dimensional analysis by a finite element large-eddy-simulation (LES) code is carried out in order to explore the mechanism of the periodical pressure fluctuation in short-elbow pipings, based on visualizations of dynamic flow structure in the numerical results.

Journal Articles

Prediction of unsteady flow field in a primary circuit hot-leg piping of a sodium-cooled fast reactor

Tanaka, Masaaki; Sago, Hiromi*; Iwamoto, Yukiharu*; Ebara, Shinji*; Ono, Ayako; Murakami, Takahiro*; Hayakawa, Satoshi*

Nihon Kikai Gakkai Rombunshu, B, 78(792), p.1392 - 1396, 2012/08

A study on flow induced vibration in the primary cooling system of Japan Sodium cooled Fast Reactor (JSFR) consisting of large diameter pipe and pipe elbow with short curvature radius ("short-elbow") has been conducted. Flow-induced vibration in the short-elbow is an important issue in design study of JSFR, because it may affect to structural integrity of the pipe. In this paper, unsteady flow characteristics in the JSFR short-elbow pipe related to the large-scale eddy motion were estimated based on knowledge from existing studies for curved pipes and scaled water experiments and numerical simulations for the JSFR hot-leg piping.

Journal Articles

Sulfate complexation of element 104, Rf, in H$$_{2}$$SO$$_{4}$$/HNO$$_{3}$$ mixed solution

Li, Z.*; Toyoshima, Atsushi; Asai, Masato; Tsukada, Kazuaki; Sato, Tetsuya; Sato, Nozomi; Kikuchi, Takahiro; Nagame, Yuichiro; Sch$"a$del, M.; Pershina, V.*; et al.

Radiochimica Acta, 100(3), p.157 - 164, 2012/03

 Times Cited Count:10 Percentile:65.97(Chemistry, Inorganic & Nuclear)

JAEA Reports

Data of groundwater from boreholes, river water and precipitation for the Horonobe Underground Research Laboratory Project; 2001-2010

Amano, Yuki; Yamamoto, Yoichi; Nanjo, Isao; Murakami, Hiroaki; Yokota, Hideharu; Yamazaki, Masanori; Kunimaru, Takanori; Oyama, Takahiro*; Iwatsuki, Teruki

JAEA-Data/Code 2011-023, 312 Pages, 2012/02

JAEA-Data-Code-2011-023.pdf:5.46MB
JAEA-Data-Code-2011-023(errata).pdf:0.08MB

In the Horonobe Underground Research Laboratory (URL) Project, ground water from boreholes, river water and precipitation have been analyzed for the environmental monitoring since the fiscal year 2001. This report shows the data set of water chemistry since the fiscal year 2001 to the fiscal year 2010.

Journal Articles

Unsteady elbow pipe flow to develop a flow-induced vibration evaluation methodology for JSFR

Yamano, Hidemasa; Tanaka, Masaaki; Ono, Ayako; Murakami, Takahiro*; Iwamoto, Yukiharu*; Yuki, Kazuhisa*; Sago, Hiromi*; Hayakawa, Satoshi*

Proceedings of International Conference on Fast Reactors and Related Fuel Cycles (FR 2009) (CD-ROM), 12 Pages, 2012/00

This paper describes the current status of flow-induced vibration evaluation methodology development for primary cooling pipes in JSFR, in particular emphasizing on recent R&D activities that investigate unsteady elbow pipe flow. The experiment using the 1/3-scale test section was performed to investigate the effect of swirl flow at the inlet. Although the flow separation region was distorted at the downstream from the elbow, the experiment clarified that the effect of swirl flow on pressure fluctuation onto the pipe wall was not significant. The simulation revealed that Reynolds number scarcely affects flow patterns and flow velocity distributions.

Journal Articles

A Finite element LES for high-${it Re}$ flow in a short-elbow pipe with undisturbed inlet velocity

Eguchi, Yuzuru*; Murakami, Takahiro*; Tanaka, Masaaki; Yamano, Hidemasa

Nuclear Engineering and Design, 241(11), p.4368 - 4378, 2011/11

 Times Cited Count:8 Percentile:58.2(Nuclear Science & Technology)

The paper is concerned with a large-eddy simulation (LES) for a high-Reynolds-number flow in a short-elbow pipe, which can potentially be employed in the primary piping system of the Japan Sodium-cooled Fast Reactor (JSFR). The basic performance of the LES is studied for an elbow pipe flow without turbulence at inlet boundary at ${it Re}$ = 1.2$$times$$10$$^{6}$$ by comparison with a flow observed in a 1/3-scale water experiment, where the flow disturbance at the pipe inlet is small. In setting up the computational conditions, special care was taken to ensure that the mesh subdivision was suitable for the simulation of the pipe flow through a theoretical consideration. We discuss the effects of the turbulence model (Smagorinsky model, WALE model) and the inlet velocity profile on the results. The mechanism of the pressure fluctuation and the origin of the fluid force are also discussed with the aid of spectral analysis and the visualization of essential hydraulic quantities.

Journal Articles

Experimental investigation and validation of neutral beam current drive for ITER through ITPA joint experiments

Suzuki, Takahiro; Akers, R.*; Gates, D. A.*; G$"u$nter, S.*; Heidbrink, W. W.*; Hobirk, J.*; Luce, T. C.*; Murakami, Masanori*; Park, J. M.*; Turnyanskiy, M.*; et al.

Nuclear Fusion, 51(8), p.083020_1 - 083020_8, 2011/08

 Times Cited Count:15 Percentile:59.3(Physics, Fluids & Plasmas)

Joint experiments investigating the off-axis neutral beam current drive (NBCD) capability to be utilized for advanced operation scenario development in ITER was conducted in 5 tokamaks (AUG, DIII-D, JT-60U, MAST and NSTX) through the ITPA. We discuss results obtained in the joint experiments, where the toroidal field, $$B$$$$_{rm t}$$, covered 0.3-3.7 T, the plasma current, $$I$$$$_{rm p}$$, 0.6-1.2 MA, and the beam energy, Eb, 67-350 keV. A current profile broadened by off-axis NBCD was observed in MAST. In DIII-D, good agreement between the measured and calculated NB driven current profile was observed. In JT-60U, agreement between measured and calculated NBCD location was obtained, when the NBCD location (0.3-0.6 in $$r$$/$$a$$), heating power (6-13 MW), triangularity $$d$$ (0.25-0.45), and $$E$$$$_{b}$$ (85 and 350 keV) were widely scanned. In AUG (at low $$delta$$$$ sim$$ 0.2) and DIII-D, introduction of a fast ion diffusion coefficient of $$D$$$$_{rm b}$$ 0.3-0.5 m$$^2$$/s in the calculation gave better agreement at high heating power (5 and 7.2 MW), suggesting anomalous transport of fast ions by turbulence. It was found through these ITPA joint experiments that NBCD related physics quantities reasonably agree with calculations (with $$D$$$$_{rm b}$$ = 0-0.5 m$$^2$$/s) in all devices when there is no MHD activity except ELMs. Proximity of measured off-axis beam driven current to the corresponding calculation with $$D$$$$_{rm b}$$ = 0 has been discussed for ITER in terms of a theoretically predicted scaling of fast-ion diffusion that depends on $$E$$$$_{rm b}$$/$$T$$$$_{rm e}$$ for electrostatic turbulence or $$beta$$$$_{rm t}$$ for electromagnetic turbulence.

Journal Articles

Unsteady elbow pipe flow to develop a flow-induced vibration evaluation methodology for Japan sodium-cooled fast reactor

Yamano, Hidemasa; Tanaka, Masaaki; Murakami, Takahiro*; Iwamoto, Yukiharu*; Yuki, Kazuhisa*; Sago, Hiromi*; Hayakawa, Satoshi*

Journal of Nuclear Science and Technology, 48(4), p.677 - 687, 2011/04

This paper describes the current status of flow-induced vibration evaluation methodology development for primary cooling pipes in Japan Sodium-cooled Fast Reactor (JSFR), in particular emphasizing on recent R&D activities that investigate unsteady elbow pipe flow.

Journal Articles

Experimental investigation and validation of neutral beam current drive for ITER through ITPA joint experiments

Suzuki, Takahiro; Akers, R.*; Gates, D. A.*; G$"u$nter, S.*; Heidbrink, W. W.*; Hobirk, J.*; Luce, T. C.*; Murakami, Masanori*; Park, J. M.*; Turnyanskiy, M.*; et al.

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2010/10

Joint experiments investigating the off-axis neutral beam current drive (NBCD) capability to be utilized for advanced operation scenario development in ITER was conducted in 4 tokamaks (AUG, DIII-D, JT-60U and MAST) through the ITPA. We discuss results obtained in the joint experiments, where the toroidal field, Bt, covered 0.3-3.7 T, the plasma current, Ip, 0.6-1.2 MA, and the beam energy, Eb, 67-350 keV. A current profile broadened by off-axis NBCD was observed in MAST. In DIII-D, good agreement between the measured and calculated NB driven current profile was observed. In JT-60U, agreement between measured and calculated NBCD location was obtained, when the NBCD location (0.3-0.6 in r/a), heating power (6-13 MW), triangularity d (0.25-0.45), and Eb (85 and 350 keV) were widely scanned. In AUG (at low d 0.2) and DIII-D, introduction of a fast ion diffusion coefficient of Db 0.3-0.5 m$$^2$$/s in the calculation gave better agreement at high heating power (5 and 7.2 MW), suggesting anomalous transport of fast ions by turbulence. It was found through these ITPA joint experiments that NBCD related physics quantities reasonably agree with calculations (with Db=0-0.5 m$$^2$$/s) in all devices when there is no MHD activity except ELMs.

Journal Articles

29th report of ITPA topical group meeting

Isayama, Akihiko; Sakakibara, Satoru*; Furukawa, Masaru*; Matsunaga, Go; Yamazaki, Kozo*; Watanabe, Kiyomasa*; Idomura, Yasuhiro; Sakamoto, Yoshiteru; Tanaka, Kenji*; Tamura, Naoki*; et al.

Purazuma, Kaku Yugo Gakkai-Shi, 86(6), p.374 - 377, 2010/06

no abstracts in English

Journal Articles

Isoscalar giant resonances in the Sn nuclei and implications for the asymmetry term in the nuclear-matter incompressibility

Li, T.*; Garg, U.*; Liu, Y.*; Marks, R.*; Nayak, B. K.*; Madhusudhana Rao, P. V.*; Fujiwara, Mamoru*; Hashimoto, Hisanobu*; Nakanishi, Kosuke*; Okumura, Shun*; et al.

Physical Review C, 81(3), p.034309_1 - 034309_11, 2010/03

 Times Cited Count:92 Percentile:97.51(Physics, Nuclear)

49 (Records 1-20 displayed on this page)