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Journal Articles

Development of reacting jet evaluation model based on engineering approaches with particle method for improvement of LEAP-III code

Kosaka, Wataru; Uchibori, Akihiro; Takata, Takashi; Yanagisawa, Hideki*; Watanabe, Akira*; Jang, S.*

Proceedings of 19th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-19) (Internet), 11 Pages, 2022/03

For the safety assessment of a steam generator (SG) in a sodium-cooled fast reactor, the analysis code LEAP-III can evaluate the water leak rate during the long-term event progress including the tube failure propagation triggered by an occurrence of a small water leak in a failed heat transfer tube in SG. The LEAP-III has the advantage in completing the calculation with low computational cost since it consists of semi-empirical formulae and one-dimensional equations of conservation. However, an evaluation model of temperature distribution by the reacting jet provides wider high temperature region than the experimental data. As a result, LEAP-III shows excessive conservativeness in some case. A Lagrangian particle method code based on engineering approaches has been developed in order to improve this model to get more realistic temperature distribution. In this method, the jet behavior and chemical reaction are simulated using Newton's equation of motion with several engineering approximations instead of solving multi-dimension multiphase thermal hydraulic equations with sodium-water reaction. In this study, interparticle interaction force model was added, and also the chemical reaction and gas-liquid heat transfer evaluation models were improved. We conducted a test analysis, and compared the results by this particle method with the ones by SERAPHIM, that is a mechanistic analysis code for multi-dimensional multiphase flow considering compressibility and sodium-water reaction. Through this test analysis, it confirmed that this particle method has the basic capability to get a realistic temperature distribution with low computational cost, and also to predict tube failure occurrence by coupled with LEAP-III.

Journal Articles

Contrasting magnetic structures in SrLaCuSbO$$_{6}$$ and SrLaCuNbO$$_{6}$$; Spin-$$frac{1}{2}$$ quasi-square-lattice $$J_{1}$$-$$J_{2}$$ Heisenberg antiferromagnets

Watanabe, Masari*; Kurita, Nubuyuki*; Tanaka, Hidekazu*; Ueno, Wataru*; Matsui, Kazuki*; Goto, Takayuki*; Hagihara, Masato

Physical Review B, 105(5), p.054414_1 - 054414_12, 2022/02

Journal Articles

Structural characterization of Eu-HONTA complexes by IBIL and EXAFS analyses

Watanabe, So; Sano, Yuichi; Okada, Makoto*; Matsuura, Haruaki*; Hagura, Naoto*; Kada, Wataru*

Nuclear Instruments and Methods in Physics Research B, 477, p.60 - 65, 2020/08

 Times Cited Count:1 Percentile:39.17(Instruments & Instrumentation)

IBIL and EXAFS analyses were applied on strucutral analysis of Eu complex formed in adsorbent developed for extraction chromatography. Those analyses revealed slight structural difference between adsorbent and solvent systems.

Journal Articles

Ion beam induced luminescence of complexes formed in adsorbent for MA recovery process

Watanabe, So; Katai, Yuya*; Matsuura, Haruaki*; Kada, Wataru*; Koka, Masashi*; Sato, Takahiro*; Arai, Tsuyoshi*

Nuclear Instruments and Methods in Physics Research B, 450, p.61 - 65, 2019/07

 Times Cited Count:1 Percentile:23.13(Instruments & Instrumentation)

Journal Articles

Cryogenic sample environments shared at the MLF, J-PARC

Kawamura, Seiko; Takahashi, Ryuta*; Ishikado, Motoyuki*; Yamauchi, Yasuhiro*; Nakamura, Masatoshi*; Ouchi, Keiichi*; Kira, Hiroshi*; Kambara, Wataru*; Aoyama, Kazuhiro*; Sakaguchi, Yoshifumi*; et al.

Journal of Neutron Research, 21(1-2), p.17 - 22, 2019/05

The Cryogenics and Magnets group in the Sample Environment team is responsible for operation of cryostats and magnets for user's experiments at the MLF in J-PARC. We have introduced a top-loading $$^4$$He cryostat, a bottom-loading $$^3$$He cryostat, a dilution refrigerator insert and a superconducting magnet. The frequency of use of them dramatically becomes higher in these two years, as the beam power and the number of proposal increase. To respond such situation, we have made efforts to enhance performance of these equipment as follows. The $$^3$$He cryostat originally involves an operation software for automatic initial cooling down to the base temperature and automatic re-charge of $$^3$$He. Recently we made an additional program for automatic temperature control with only the sorb heater. Last year, a new outer vacuum chamber of the magnet with an oscillating radial collimator (ORC) was fabricated. The data quality was drastically improved by introducing this ORC so that the magnet can be used even for the inelastic neutron scattering experiments.

Journal Articles

Materials and Life Science Experimental Facility at the Japan Proton Accelerator Research Complex, 3; Neutron devices and computational and sample environments

Sakasai, Kaoru; Sato, Setsuo*; Seya, Tomohiro*; Nakamura, Tatsuya; To, Kentaro; Yamagishi, Hideshi*; Soyama, Kazuhiko; Yamazaki, Dai; Maruyama, Ryuji; Oku, Takayuki; et al.

Quantum Beam Science (Internet), 1(2), p.10_1 - 10_35, 2017/09

Neutron devices such as neutron detectors, optical devices including supermirror devices and $$^{3}$$He neutron spin filters, and choppers are successfully developed and installed at the Materials Life Science Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC), Tokai, Japan. Four software components of MLF computational environment, instrument control, data acquisition, data analysis, and a database, have been developed and equipped at MLF. MLF also provides a wide variety of sample environment options including high and low temperatures, high magnetic fields, and high pressures. This paper describes the current status of neutron devices, computational and sample environments at MLF.

JAEA Reports

Study on small-sized tailless beam formation using multipole magnetic field (Joint research)

Yokota, Wataru; Yuri, Yosuke; Watanabe, Shinichi*; Oshiro, Yukimitsu*; Kubono, Shigeru*

JAEA-Technology 2016-005, 21 Pages, 2016/03

JAEA-Technology-2016-005.pdf:2.24MB

The Center of Nuclear Science (CNS) of Tokyo University conducts the research on nuclear physics using CNS Radio-Isotope Beam Separator (CRIB) installed at the RIKEN AVF cyclotron. Takasaki Advanced Radiation Research Institute, JAEA has an AVF cyclotron of similar scale and is developing a technology to form a large-area uniform beam by an octupole magnetic field for the research on materials science. They carried out an R&D to increase the cyclotron beam intensity at a target under joint research. The nonlinear beam optics was designed to form a usual cyclotron beam having a large transverse tail into a small-sized tailless distribution so that the beam passes the gas target orifice (6 mm in diameter) of CRIB without a loss. As a result of particle tracking simulations based on the measured beam emittance, it has been found that an octupole magnetic field is effective in tail-folding and a 10-mm-diameter beam can be formed with two octupole magnets added in the present beam line. It has been also found that additional magnets need to be installed and the beam emittance should be reduced for the objective beam size of 6 mm. Moreover, the objective may be attained if the beam path length and configuration of the magnetic lens system are freely chosen.

Journal Articles

Particle induced X-ray emission-computed tomography analysis of an adsorbent for extraction chromatography

Sato, Takahiro; Yokoyama, Akihito; Kitamura, Akane; Okubo, Takeru; Ishii, Yasuyuki; Takahatake, Yoko; Watanabe, So; Koma, Yoshikazu; Kada, Wataru*

Nuclear Instruments and Methods in Physics Research B, 371, p.419 - 423, 2016/03

 Times Cited Count:4 Percentile:45.9(Instruments & Instrumentation)

Journal Articles

Operation status of interlock system of Materials and Life Science Experimental Facility (MLF) in J-PARC

Sakai, Kenji; Kai, Tetsuya; Oi, Motoki; Watanabe, Akihiko; Nakatani, Takeshi; Higemoto, Wataru; Meigo, Shinichiro; Sakamoto, Shinichi; Takada, Hiroshi; Futakawa, Masatoshi

Progress in Nuclear Science and Technology (Internet), 4, p.264 - 267, 2014/04

no abstracts in English

Journal Articles

Thermoresponsive extraction of cadmium(II) ions by poly(TPEN-NIPA) gels; Effect of chain length and branched spacer structure on gel formation and extraction behavior

Inaba, Yusuke*; Tsumagari, Takayuki*; Kida, Tatsuya*; Watanabe, Wataru*; Nakajima, Yasutaka*; Fukuoka, Sachio*; Mori, Atsunori*; Matsumura, Tatsuro; Nakano, Yoshio*; Takeshita, Kenji*

Polymer Journal, 43(7), p.630 - 634, 2011/07

 Times Cited Count:11 Percentile:39.61(Polymer Science)

${it N,N,N',N'}$-(tetrakis-2-pyridylmethyl)ethylenediamine (TPEN) derivatives bearing a polymerizable double bond in the substituent structure of the pyridine ring are synthesized and subjected to copolymerization with ${it N}$-isopropylacrylamide in the presence of AIBN. The obtained poly(TPEN-NIPA) gels show thermo-responsive swelling/shrinking behaviors and are employed for the extraction of cadmium(II) ion from the aqueous solution to examine the relationship of the gel characteristics and the extraction performance. The polymer gels composed of the TPEN derivative bearing C3, C4, C10 and branched C3 spacer chains are synthesized and temperature-dependent extraction behavior of cadmium ion is compared. These gels extract Cd(II) ion efficiently from the aqueous solution in the swelling state at 5$$^{circ}$$C, while little extraction is observed at 45$$^{circ}$$C with shrinking. It is found that poly(TPEN-NIPA) gel of branched C3 spacer (C3b) shows the excellent thermoresponsive extraction performance.

Journal Articles

Thermo-responsive extraction of cadmium(II) ion with TPEN-NIPA gel; Effect of the number of polymerizable double bond toward gel formation and the extracting behavior

Fukuoka, Sachio*; Kida, Tatsuya*; Nakajima, Yasutaka*; Tsumagari, Takayuki*; Watanabe, Wataru*; Inaba, Yusuke*; Mori, Atsunori*; Matsumura, Tatsuro; Nakano, Yoshio*; Takeshita, Kenji*

Tetrahedron, 66(9), p.1721 - 1727, 2010/02

 Times Cited Count:17 Percentile:50.38(Chemistry, Organic)

N,N,N',N'-(tetrakis-2-pyridylmethyl)ethylenediamine (TPEN) derivatives bearing the different number (1-4) of a double bond moiety on the pyridine ring are synthesized and subjected to copolymerization with N-isopropylacrylamide in the presence of AIBN. The obtained poly(TPEN-NIPA)gels show thermo-responsive swelling/shrinking behaviors and are employed for the extraction of cadmium(II) ion from the aqueous solution to examine the relationship of the gel characteristics and the extraction performance. The polymer gels composed of the TPEN derivative bearing three or four double bonds exhibit temperature-dependent change of swelling and shrinking in water. These gels extract CdII ion efficiently from the aqueous solution in the swelling state at 5$$^{circ}$$C, while little extraction was observed at 45$$^{circ}$$C with shrinking.

JAEA Reports

Design, construction and operation of general control system of Materials and Life Science Experimental Facility (MLF-GCS) in J-PARC

Sakai, Kenji; Oi, Motoki; Kai, Tetsuya; Watanabe, Akihiko; Nakatani, Takeshi; Higemoto, Wataru; Shimomura, Koichiro*; Kinoshita, Hidetaka; Kaminaga, Masanori

JAEA-Technology 2009-042, 44 Pages, 2009/08

JAEA-Technology-2009-042.pdf:35.33MB

A general control system for the Materials and Life Science Experimental Facility (MLF-GCS) at J-PARC has an advanced and independent system for control of the mercury target, including a large amount of mercury, three moderators with supercritical hydrogen, and cooling systems with radioactive water. Although the MLF-GCS is an independent system, it works closely with the accelerator and other facility control systems within J-PARC. The MLF have succeeded in the first proton beam injection and neutron beam generation in May 2008, and succeeded the muon beams generation in September 2008. The design and construction of the MLF-GCS has finished before the first proton beam injection. It has been operated stably and efficiently in the off- and on- beam commissioning. This paper reports on the design, construction and operation of the MLF-GCS.

Journal Articles

Formation of a uniform ion beam using multipole magnets

Yuri, Yosuke; Ishizaka, Tomohisa; Yuyama, Takahiro; Okumura, Susumu; Ishibori, Ikuo; Yokota, Wataru; Watanabe, Shinichi*; Kubono, Shigeru*; Oshiro, Yukimitsu*

Proceedings of 2009 Particle Accelerator Conference (PAC '09) (DVD-ROM), p.3895 - 3897, 2009/05

Journal Articles

Establishment of a rearing system of the extremotolerant tardigrade ${it Ramazzottius varieornatus}$; A New model animal for astrobiology

Horikawa, Daiki*; Kunieda, Takekazu*; Abe, Wataru*; Watanabe, Masahiko*; Nakahara, Yuichi*; Yukuhiro, Fumiko*; Sakashita, Tetsuya; Hamada, Nobuyuki*; Wada, Seiichi*; Funayama, Tomoo; et al.

Astrobiology, 8(3), p.549 - 556, 2008/06

 Times Cited Count:70 Percentile:89.07(Astronomy & Astrophysics)

We report the successful rearing of the herbivorous tardigrade, ${it Ramazzottius varieornatus}$, by supplying the green alga ${it Chlorella vulgaris}$ as food. The life span was 35 d, deposited eggs required 5.7 d to hatch, and animals began to deposit eggs 9 d after hatching. The reared individuals of this species had an anhydrobiotic capacity throughout their life cycle in egg, juvenile, and adult stages. Furthermore, the reared adults in an anhydrobiotic state were tolerant of temperatures of 90$$^{circ}$$C and -196$$^{circ}$$C and exposure to 99.8% acetonitrile or irradiation with 4000 Gy $$^{4}$$He ions. Based on their life history traits and tolerance to extreme stresses, ${it R. varieornatus}$ might be a suitable model for astrobiological studies of multicellular organisms.

Journal Articles

Muon spin rotation study of magnetism in multilayer HgBa$$_2$$Ca$$_4$$Cu$$_5$$O$$_y$$ superconductor

Tokiwa, Kazuyasu*; Mikusu, Satoshi*; Higemoto, Wataru; Nishiyama, Kusuo*; Iyo, Akira*; Tanaka, Yasumoto*; Kotegawa, Hisashi*; Mukuda, Hidekazu*; Kitaoka, Yoshio*; Watanabe, Tsuneo*

Physica C, 460-462(2), p.892 - 895, 2007/09

 Times Cited Count:3 Percentile:18.97(Physics, Applied)

Zero- and longitudinal-field muon-spin rotation (ZF-$$mu$$SR and LF-$$mu$$SR) measurements were carried out on a multi-layered HgBa$$_2$$Ca$$_4$$Cu$$_5$$O$$_y$$ (Hg-1245) superconductor with $$T$$$$_{rm c}$$ of 108 K. With decreasing temperature, the observed ZF-$$mu$$SR function changed from a Gaussian-type to an exponential-type below 60 K and zero field muon precession was also observed below 45 K. These $$mu$$SR signals are attributed to the development of the antiferromagnetic ordering in inner CuO$$_2$$planes with a low carrier concentration. These results seem to indicate clear evidence that antiferromagnetism microscopically coexists with superconductivity in the Hg-1245 superconductor below 60 K.

Journal Articles

$$mu$$SR study of impurity effects on the Cu-spin fluctuations in the overdoped regime of La$$_{2-x}$$Sr$$_x$$Cu$$_{1-y}$$Zn$$_y$$O$$_4$$

Risdiana*; Adachi, Tadashi*; Oki, Naoki*; Yairi, Satoshi*; Tanabe, Yoichi*; Omori, Keisuke*; Suzuki, Takao*; Watanabe, Isao*; Koda, Akihiro*; Higemoto, Wataru; et al.

Physica C, 460-462(2), p.874 - 875, 2007/09

 Times Cited Count:3 Percentile:18.97(Physics, Applied)

Zero-field muon-spin-relaxation measurements have been carried out for La$$_{2-x}$$Sr$$_x$$Cu$$_{1-y}$$Zn$$_y$$O$$_4$$ (LSCO)with $$y$$ = 0-0.10 in the overdoped regime up to $$x$$ = 0.30, in order to investigate whether the dynamical stripe correlations are pinned and stabilized even for the overdoped LSCO or not. It has been found that the Zn-induced slowing down of the Cu-spin fluctuations is weakened with increasing $$x$$ but takes place in the overdoped regime and disappears at $$x$$ = 0.30. This suggests that the stripe-pinning model holds good in the whole superconducting regime of LSCO and that there is no quantum critical point at $$x$$ $$sim$$ 0.19.

Journal Articles

Status of J-PARC muon science facility at the year of 2005

Miyake, Yasuhiro*; Nishiyama, Kusuo*; Kawamura, Naritoshi*; Makimura, Shunsuke*; Strasser, P.*; Shimomura, Koichiro*; Beveridge, J. L.*; Kadono, Ryosuke*; Fukuchi, Koichi*; Sato, Nobuhiko*; et al.

Physica B; Condensed Matter, 374-375, p.484 - 487, 2006/03

 Times Cited Count:6 Percentile:32.73(Physics, Condensed Matter)

The construction of the Materials and Life Science building was started in the beginning of the fiscal year of 2004. After commissioning of the accelerator and beam transport sections in 2008, muon beams will be available for users in 2009. In this letter, the latest construction status of the J-PARC Muon Science Facility is reported.

Journal Articles

Possible weak magnetism in MB$$_6$$ (M: Ca, Ba) probed by muon spin relaxation and muon level-crossing resonance

Kuroiwa, Sogo*; Takagiwa, Hiroyuki*; Yamazawa, Maki*; Akimitsu, Jun*; Koda, Akihiro*; Kadono, Ryosuke*; Oishi, Kazuki; Higemoto, Wataru; Watanabe, Isao*

Science and Technology of Advanced Materials, 7(1), p.12 - 16, 2006/01

 Times Cited Count:4 Percentile:19.96(Materials Science, Multidisciplinary)

The temperature dependence of muon spin relaxation rate exhibits a significant increase below $$sim$$130 K in CaB$$_6$$ and $$sim$$110 K in BaB$$_6$$, while no sigh of spontaneous muon precession signal under a zero field is observed. Moreover, the electric field gradient at the boron site measured by muon level-crossing resonance exhibits a step like change at $$sim$$110 K in CaB$$_6$$. These results suggest a change in electronic state and the associated emergence of weak random magnetism below 110-130 K in these alkaline earth hexaborides.

Journal Articles

J-PARC muon science facility with use of 3GeV proton beam

Miyake, Yasuhiro*; Kawamura, Naritoshi*; Makimura, Shunsuke*; Strasser, P.*; Shimomura, Koichiro*; Nishiyama, Kusuo*; Beveridge, J. L.*; Kadono, Ryosuke*; Sato, Nobuhiko*; Fukuchi, Koichi*; et al.

Nuclear Physics B; Proceedings Supplements, 149, p.393 - 395, 2005/12

The J-PARC muon science experimental area is planned to be located in the integrated building of the facility for materials and life science study. One muon target will be installed upstream of the neutron target. The main feature of the facility is introduced.

JAEA Reports

An Investigation of post-irradiation examination facility for fusion blanket materials

Yamada, Hirokazu*; Kawamura, Hiroshi; Tsuchiya, Kunihiko; Ishitsuka, Etsuo; Uchida, Munenori*; Akutsu, Yoichi; Motoki, Ryozo; Watanabe, Wataru; Hirata, Shogo*

JAERI-Tech 2004-036, 138 Pages, 2004/03

JAERI-Tech-2004-036.pdf:4.07MB

This document shows the model case concerned with the utilization of constructed facility for the construction of post irradiation examination facility for fusion blanket. In this report, the radioisotope application and development laboratory is considered as constructed facility for post irradiation examination facility and we planned to improve the radioisotope application and development laboratory to the facility of post irradiation examination for fusion material to reduce the construction fee for this facility and promotion of efficiency by concentration of any equipment for fusion material research.

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