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Okagaki, Yuria; Shibamoto, Yasuteru; Wada, Yuki; Abe, Satoshi; Hibiki, Takashi*
Journal of Nuclear Science and Technology, 60(8), p.955 - 968, 2023/08
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)Aoyagi, Mitsuhiro; Sonehara, Masateru; Ishida, Shinya; Uchibori, Akihiro; Kawada, Kenichi; Okano, Yasushi; Takata, Takashi
Proceedings of Technical Meeting on State-of-the-art Thermal Hydraulics of Fast Reactors (Internet), 3 Pages, 2022/09
Sonehara, Masateru; Uchibori, Akihiro; Aoyagi, Mitsuhiro; Kawada, Kenichi; Takata, Takashi; Ohshima, Hiroyuki
Dai-25-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu (Internet), 3 Pages, 2021/07
In sodium-cooled fast reactors (SFRs), it has been pointed out that molten fuel may be discharged from the core during a severe accident (SA) accompanied by core damage, and may solidify into debri particles with diameters ranging from several millimeters to several hundred micrometers due to interaction with the sodium coolant and accumulate at the bottom of the reactor vessel. Therefore, it is necessary to understand the behavior of such debri particles appropriately to evaluate the SA event progression. To meet these requirements, a molten fuel behavior analysis code using dissipative particle dynamics (DPD), a kind of particle method, has been developed as a part of the SPECTRA code, tool for consistent analysis of in-vessel and ex-vessel events in sodium fast reactor accidents. In this study, it was found that the new analyses code can reproduce sedimentation behavior of particles by adding a new stress term in the shear direction.
Watanabe, Hiroshi*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Andreyev, A. N.; Hashimoto, Takashi*; Kondev, F. G.*; Lane, G. J.*; Litvinov, Yu. A.*; Liu, J. J.*; Miyatake, Hiroari*; et al.
Physics Letters B, 814, p.136088_1 - 136088_6, 2021/03
Times Cited Count:4 Percentile:46.8(Astronomy & Astrophysics)Ebisuzaki, Toshikazu*; Wada, Satoshi*; Saito, Norihito*; Fujii, Takashi*; Nishimura, Akihiko
Reza Kenkyu, 45(10), p.664 - 665, 2017/10
no abstracts in English
Hamada, Takashi; Hasegawa, Shin; Fukasawa, Hideyuki*; Sawada, Shinichi; Koshikawa, Hiroshi; Miyashita, Atsumi; Maekawa, Yasunari
Journal of Materials Chemistry A, 3(42), p.20983 - 20991, 2015/11
Times Cited Count:34 Percentile:70.73(Chemistry, Physical)no abstracts in English
Nakajima, Kyo*; Teramoto, Takahiro*; Akagi, Hiroshi; Fujikawa, Takashi*; Majima, Takuya*; Minemoto, Shinichiro*; Ogawa, Kanade*; Sakai, Hirofumi*; Togashi, Tadashi*; Tono, Kensuke*; et al.
Scientific Reports (Internet), 5, p.14065_1 - 14065_11, 2015/09
Times Cited Count:38 Percentile:84.13(Multidisciplinary Sciences)We report on the measurement of deep inner-shell 2p X-ray photoelectron diffraction (XPD) patterns from laser-aligned I molecules using X-ray free-electron laser (XFEL) pulses. The XPD patterns of the I molecules, aligned parallel to the polarization vector of the XFEL, were well matched with our theoretical calculations. Further, we propose a criterion for applying our molecular-structure-determination methodology to the experimental XPD data. In turn, we have demonstrated that this approach is a significant step toward the time-resolved imaging of molecular structures.
Watanabe, Kazuyo*; Akitsuki, Takashi*; Shimura, Sachiko*; Gusev, O.*; Cornette, R.*; Kikawada, Takahiro*; Sakashita, Tetsuya; Funayama, Tomoo; Kobayashi, Yasuhiko; Okuda, Takashi*
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 87, 2015/03
The Sleeping Chironomid, can stand complete desiccation (anhydrobiosis) and also shows radio-resistance. Recently, we have generated cultured cell (Pv11) originated from embryo which can also stand complete dehydration. In this study, we examine the tolerance of cultured cell Pv11 against ionbeam irradiation.
Sato, Takahiro*; Iwasaki, Atsushi*; Owada, Shigeki*; Yamanouchi, Kaoru*; Takahashi, Eiji*; Midorikawa, Katsumi*; Aoyama, Makoto; Yamakawa, Koichi; Togashi, Tadashi*; Fukami, Kenji*; et al.
Journal of Physics B; Atomic, Molecular and Optical Physics, 46(16), p.164006_1 - 164006_6, 2013/08
Times Cited Count:3 Percentile:19.06(Optics)By introducing 13th- (61.7 nm) and 15th-order harmonics (53.4 nm) of femtosecond laser pulses at 800 nm into an undulator of SCSS (SPring-8 Compact SASE Source) test accelerator at RIKEN, these harmonic pulses were amplified by a factor of more than 10 with a high contrast ratio through the interaction between accelerated electron bunches and the harmonic pulses. From numerical simulations of the amplification processes of high-order harmonic pulses in the undulator, optimum conditions of the electron bunch duration interacting with the high-order harmonic pulses were investigated for generating full-coherent and intense pulses in the extreme ultraviolet wavelength region.
Ogawa, Kanade*; Sato, Takahiro*; Matsubara, Shinichi*; Okayasu, Yuichi*; Togashi, Tadashi*; Watanabe, Takahiro*; Takahashi, Eiji*; Midorikawa, Katsumi*; Aoyama, Makoto; Yamakawa, Koichi; et al.
Proceedings of 10th Conference on Lasers and Electro-Optics Pacific Rim and 18th OptoElectronics and Communications Conference and Photonics in Switching 2013 (CLEO-PR & OECC/PS 2013) (USB Flash Drive), 2 Pages, 2013/06
no abstracts in English
Togashi, Tadashi*; Takahashi, Eiji*; Midorikawa, Katsumi*; Aoyama, Makoto; Yamakawa, Koichi; Sato, Takahiro*; Iwasaki, Atsushi*; Owada, Shigeki*; Yamanouchi, Kaoru*; Hara, Toru*; et al.
Proceedings of Ultrafast Optics IX (CD-ROM), 2 Pages, 2013/03
We have demonstrated free-electron laser radiation seeded by high-order harmonics in the extreme-ultraviolet region. Strong enhancement of the radiation intensity by a factor of 104 was observed with timing control of an electro-optical sampling technique.
Kishida, Kiyoshi*; Sawada, Atsushi; Yasuhara, Hideaki*; Hosoda, Takashi*
Soils and Foundations, 53(1), p.105 - 116, 2013/02
Times Cited Count:22 Percentile:62.23(Engineering, Geological)Considering the safe, long-term sequestration of energy byproducts, such as radioactive waste, one of the important parameters is the groundwater flow velocity through the void of rock masses and/or fractures. In this research work, two-dimensional seepage flow analyses, using the authors' proposed 2D model, with considering the inertia term, are carried out for single fracture permeability tests under conditions which allow for the application of the cubic law. In comparing the results of the experiments with the numerical simulations, the results of the simulation show a good agreement with the experimental results. From these simulation results, the fracture flow of an inhomogeneous structure is discussed, along with the local Reynolds number, and the resistance through the fracture geometry is considered. Consequently, under the condition of a mean Reynolds number of less than 1.0, the inertia terms cannot affect on the fracture flow, but the hydraulic resistance can affect.
Sonoda, Tetsu*; Wada, Michiharu*; Tomita, Hideki*; Sakamoto, Chika*; Takatsuka, Takaaki*; Furukawa, Takeshi*; Iimura, Hideki; Ito, Yuta*; Kubo, Toshiyuki*; Matsuo, Yukari*; et al.
Nuclear Instruments and Methods in Physics Research B, 295, p.1 - 10, 2013/01
Times Cited Count:21 Percentile:83.85(Instruments & Instrumentation)no abstracts in English
Wada, Tamotsu*; Sakuma, Takashi*; Sakai, Ryutaro*; Uehara, Hiroyuki*; Xianglian*; Takahashi, Haruyuki*; Kamishima, Osamu*; Igawa, Naoki; Danilkin, S. A.*
Solid State Ionics, 225, p.18 - 21, 2012/10
Times Cited Count:12 Percentile:44.07(Chemistry, Physical)Diffuse neutron scattering measurement on AgO crystals was performed at 8 K and 295 K. The observed diffuse scattering intensities were analyzed by including the correlation effects among thermal displacements of atoms in AgO. Using the values of correlation effects among neighboring atoms and the values of Debye-Waller temperature parameter, force constants among first, second and third nearest neighboring atoms have been evaluated.
Togashi, Tadashi*; Takahashi, Eiji*; Midorikawa, Katsumi*; Aoyama, Makoto; Yamakawa, Koichi; Sato, Takahiro*; Iwasaki, Atsushi*; Owada, Shigeki*; Yamanouchi, Kaoru*; Hara, Toru*; et al.
Proceedings of 11th International School and Symposium on Synchrotron Radiation in Natural Science (ISSRNS 2012), p.1 - 21, 2012/05
The 13th harmonic of a Ti:sapphire laser has been significantly amplified with the SCSS test accelerator. The temporal and spatial overlap of the electron beam and the high harmonic radiation were precisely tuned for achieving the seeded free electron laser operation. With numerical simulation the present HH-seeded FEL scheme could readily be applied to the wavelength region down to 10 nm.
Horikawa, Daiki*; Yamaguchi, Ayami*; Sakashita, Tetsuya; Tanaka, Daisuke*; Hamada, Nobuyuki*; Yukuhiro, Fumiko*; Kuwahara, Hirokazu*; Kunieda, Takekazu*; Watanabe, Masahiko*; Nakahara, Yuichi*; et al.
Astrobiology, 12(4), p.283 - 289, 2012/04
Times Cited Count:23 Percentile:68.76(Astronomy & Astrophysics)We examined the hatchability of hydrated and anhydrobiotic eggs of the tardigrade to hatch after ionizing irradiation (helium ions), extremely low and high temperatures, and high vacuum. Anhydrobiotic eggs (50% lethal dose; 1690 Gy) were substantially more radioresistant than hydrated ones (50% lethal dose; 509 Gy). Anhydrobiotic eggs also have a broader temperature resistance compared with hydrated ones. Over 70% of the anhydrobiotic eggs treated at high and low temperatures, but all of the hydrated eggs failed to hatch. After exposure to high vacuum conditions, the hatchability of the anhydrobiotic eggs was comparable to that of untreated control eggs.
Kishida, Kiyoshi*; Hosoda, Takashi*; Sawada, Atsushi; Sato, Hisashi; Nakashima, Shinichiro*; Yasuhara, Hideaki*
Harmonising Rock Engineering and the Environment, p.1327 - 1330, 2011/10
Although it is generally known that a natural rock fracture indicates a complex aperture distribution, the fracture is an ideal representation of the parallel plate model. The cubic law is applied to evaluate the hydraulic properties of fractured rock. From several previous research works, it is known that the cubic law can be applied when the Reynolds number is less than 1.0 and that the advection term can basically be ignored in such fracture flows. In this research work, two-dimensional seepage flow analyses, using the authors' proposed 2D model which is considered with the advection term, are carried out for single fracture hydro-conductivity experiments under conditions which allow for the application of the cubic law. From the numerical results, the validity of the 2D model is discussed along with the local Reynolds number and the application of the cubic law.
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:184 Percentile:99.44(Physics, Nuclear)Transverse momentum distributions and yields for , and in collisions at = 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 collisions. We also present the scaling properties such as and scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
Takahashi, Eiji*; Togashi, Tadashi*; Midorikawa, Katsumi*; Aoyama, Makoto; Yamakawa, Koichi; Sato, Takahiro*; Iwasaki, Atsushi*; Owada, Shigeki*; Yamanouchi, Kaoru*; Hara, Toru*; et al.
Proceedings of European Conference on Lasers and Electro-Optics and the 12th European Quantum Electronics Conference (CLEO/Europe-EQEC 2011) (CD-ROM), 1 Pages, 2011/05
We succeeded in generating the seeded free electron laser (FEL) with wavelengths of 61 nm at the SCSS test accelerator. The 13th (61 nm) harmonics generated by focusing the high peak power Ti:Sapphire laser to the Xe gas cell was directed to the undulator. This is first realization of the seeded FEL in extreme ultraviolet region.
Takahashi, Eiji*; Togashi, Tadashi*; Aoyama, Makoto; Yamakawa, Koichi; Sato, Takahiro*; Iwasaki, Atsushi*; Owada, Shigeki*; Yamanouchi, Kaoru*; Hara, Toru*; Matsubara, Shinichi*; et al.
Proceedings of International Quantum Electronics Conference and the Pacific Rim Conference on Lasers and Electro-Optics (IQEC/CLEO Pacific Rim 2011) (CD-ROM), p.199 - 200, 2011/05
We succeeded in generating the seeded free electron laser (FEL) with wavelengths of 61 nm at the SCSS test accelerator. The 13th (61 nm) harmonics generated by focusing the high peak power Ti:Sapphire laser to the Xe gas cell was directed to the undulator. This is first realization of the seeded FEL in extreme ultraviolet region.