Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Cao, Y.*; Zhou, H.*; Khmelevskyi, S.*; Lin, K.*; Avdeev, M.*; Wang, C.-W.*; Wang, B.*; Hu, F.*; Kato, Kenichi*; Hattori, Takanori; et al.
Chemistry of Materials, 35(8), p.3249 - 3255, 2023/04
Times Cited Count:2 Percentile:37.82(Chemistry, Physical)Hydrostatic and chemical pressure are efficient stimuli to alter the crystal structure and are commonly used for tuning electronic and magnetic properties in materials science. However, chemical pressure is difficult to quantify and a clear correspondence between these two types of pressure is still lacking. Here, we study intermetallic candidates for a permanent magnet with a negative thermal expansion (NTE). Based on in situ synchrotron X-ray diffraction, negative chemical pressure is revealed in HoFe on Al doping and quantitatively evaluated by using temperature and pressure dependence of unit cell volume. A combination of magnetization and neutron diffraction measurements also allowed one to compare the effect of chemical pressure on magnetic ordering with that of hydrostatic pressure. Intriguingly, pressure can be used to control suppression and enhancement of NTE. Electronic structure calculations indicate that pressure affected the top of the majority band with respect to the Fermi level, which has implications for the magnetic stability, which in turn plays a critical role in modulating magnetism and NTE. This work presents a good example of understanding the effect of pressure and utilizing it to control properties of functional materials.
Sun, X. H.*; Wang, H.*; Otsu, Hideaki*; Sakurai, Hiroyoshi*; Ahn, D. S.*; Aikawa, Masayuki*; Fukuda, Naoki*; Isobe, Tadaaki*; Kawakami, Shunsuke*; Koyama, Shumpei*; et al.
Physical Review C, 101(6), p.064623_1 - 064623_12, 2020/06
Times Cited Count:6 Percentile:54.42(Physics, Nuclear)The spallation and fragmentation reactions of Xe induced by proton, deuteron and carbon at 168 MeV/nucleon were studied at RIKEN Radioactive Isotope Beam Factory via the inverse kinematics technique. The cross sections of the lighter products are larger in the carbon-induced reactions due to the higher total kinetic energy of carbon. The energy dependence was investigated by comparing the newly obtained data with previous results obtained at higher reaction energies. The experimental data were compared with the results of SPACS, EPAX, PHITS and DEURACS calculations. These data serve as benchmarks for the model calculations.
Motokura, Ken*; Fukuda, Takuma*; Uemura, Yohei*; Matsumura, Daiju; Ikeda, Marika*; Nambo, Masayuki*; Chun, W.-J.*
Catalysts, 8(3), p.106_1 - 106_8, 2018/03
Times Cited Count:4 Percentile:9.04(Chemistry, Physical)Sakaki, Hironao; Fukuda, Yuji; Nishiuchi, Mamiko; Jinno, Satoshi; Kanasaki, Masato; Yogo, Akifumi; Kondo, Kiminori; Saito, Fumihiro; Fukami, Tomoyo; Ueno, Masayuki; et al.
Progress in Nuclear Science and Technology (Internet), 4, p.182 - 185, 2014/04
The concept of a compact ion particle accelerator has become attractive in view of recent progress in laser-driven ions acceleration. In the development of many applications of laser-accelerated ions, it is necessary for securing the radiation safety to calculate the dose evaluation. The dose was measured with the radio-photoluminescent (RPL) glass dosimeter on the test beamline of at laser-driven accelerator. The Monte Carlo code, PHITS (Particle and Heavy Ion Transport code system) simulation is shown to be reasonably predictive at the test beamline for measured with the RPL glass dosimeter. We compare of the measured dose level on the laser-driven accelerator with the result of PHITS code in this report.
Kunimaru, Takanori; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Ishibashi, Masayuki; Sasao, Eiji; Hikima, Ryoichi; Tanno, Takeo; Sanada, Hiroyuki; et al.
JAEA-Review 2013-018, 169 Pages, 2013/09
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in 2011 fiscal year. This report shows the results of the investigation, construction and collaboration studies in fiscal year 2011, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.
Kiriyama, Hiromitsu; Shimomura, Takuya; Mori, Michiaki; Nakai, Yoshiki*; Tanoue, Manabu; Kondo, Shuji; Kanazawa, Shuhei; Pirozhkov, A. S.; Esirkepov, T. Z.; Hayashi, Yukio; et al.
Applied Sciences (Internet), 3(1), p.214 - 250, 2013/03
Times Cited Count:15 Percentile:47.77(Chemistry, Multidisciplinary)This paper reviews techniques for improving the temporal contrast and spatial beam quality in an ultra-intense laser system that is based on chirped-pulse amplification (CPA). We describe the design, performance, and characterization of our laser system, which has the potential for achieving a peak power of 600 TW. We also describe applications of the laser system in the relativistically dominant regime of laser-matter interactions and discuss a compact, high efficiency diode-pumped laser system.
Ida, Katsumi*; Fujita, Takaaki; Fukuda, Takeshi*; Sakamoto, Yoshiteru; Ide, Shunsuke; Toi, Kazuo*; Inagaki, Shigeru*; Shimozuma, Takashi*; Kubo, Shin*; Idei, Hiroshi*; et al.
Plasma Physics and Controlled Fusion, 46(5A), p.A45 - A50, 2004/05
Times Cited Count:19 Percentile:52.43(Physics, Fluids & Plasmas)no abstracts in English
Kamada, Yutaka; Fujita, Takaaki; Ishida, Shinichi; Kikuchi, Mitsuru; Ide, Shunsuke; Takizuka, Tomonori; Shirai, Hiroshi; Koide, Yoshihiko; Fukuda, Takeshi; Hosogane, Nobuyuki; et al.
Fusion Science and Technology (JT-60 Special Issue), 42(2-3), p.185 - 254, 2002/09
Times Cited Count:34 Percentile:45.45(Nuclear Science & Technology)With the main aim of providing physics basis for ITER and the steady-state tokamak reactors, JT-60/JT-60U has been developing and optimizing the operational concepts, and extending the discharge regimes toward sustainment of high integrated performance in the reactor relevant parameter regime. In addition to achievement of the equivalent break-even condition (QDTeq up to 1.25) and a high fusion triple product = 1.5E21 m-3skeV, JT-60U has demonstrated the integrated performance of high confinement, high beta-N, full non-inductive current drive with a large fraction of bootstrap current in the reversed magnetic shear and in the high-beta-p ELMy H mode plasmas characterized by both internal and edge transport barriers. The key factors in optimizing these plasmas are profile and shape controls. As represented by discovery of various Internal Transport Barriers, JT-60/JT-60U has been emphasizing freedom and restriction of profiles in various confinement modes. JT-60U has demonstrated applicability of these high confinement modes to ITER and also clarified remaining issues.
JRR-2 Control Office; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Kohayakawa, Toru; Morozumi, Minoru; Kambayashi, Yuichiro; Shitomi, Hajimu; Kokanezawa, Takashi; et al.
JAERI 1027, 57 Pages, 1962/09
no abstracts in English
JRR-2 Critical Experiments Group; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Kohayakawa, Toru; Morozumi, Minoru; Kambayashi, Yuichiro; Shitomi, Hajimu; Kokanezawa, Takashi; et al.
JAERI 1025, 62 Pages, 1962/03
no abstracts in English
Kiriyama, Hiromitsu; Mori, Michiaki; Shimomura, Takuya; Tanoue, Manabu; Kondo, Shuji; Kanazawa, Shuhei; Daito, Izuru; Suzuki, Masayuki*; Okada, Hajime; Ochi, Yoshihiro; et al.
no journal, ,
We describe two specific high intensity laser systems that are being developed in our laboratory for many applications such as high field science, nonlinear optics. We report on an ultra-high intensity petawatt-class Ti:sapphire chirped-pulse amplification laser system that can produce a pulse energy of 18 J with 30 fs pulse duration for studying extremely high intensity laser matter interaction process and a small-scaled Yb:YAG chirped-pulse amplification laser system that can generate a pulse energy of 100 m J of 500 fs pulse duration for compact, high efficiency, high repetition system. We discuss the basic design aspects and present the results from our experimental investigations of these laser systems.
Kiriyama, Hiromitsu; Nagashima, Keisuke; Ochi, Yoshihiro; Mori, Michiaki; Tanaka, Momoko; Sasao, Fumitaka; Kosuge, Atsushi; Okada, Hajime; Kondo, Kiminori; Sagisaka, Akito; et al.
no journal, ,
We have developed a femtosecond high intensity laser system, which combines both Ti:sapphire chirped-pulse amplification (CPA) and optical parametric chirped-pulse amplification (OPCPA) techniques, that produces more than 30 J broadband output energy, indicating the potential for achieving peak powers in excess of 500 TW. With a cleaned high-energy seeded OPCPA preamplifier as a front-end in the system, for the final compressed pulse we found that the temporal contrast in this system exceeds 10 on the sub-nanosecond timescale before the main femtosecond pulse. Using diffractive optical elements for beam homogenization of 100-J level high-energy Nd:glass green pump laser in a Ti:sapphire final amplifier, we have successfully generated broadband high-energy output with near-perfect top-hat intensity distributions.
Kiriyama, Hiromitsu; Mori, Michiaki; Shimomura, Takuya; Nakai, Yoshiki*; Tanoue, Manabu*; Sasao, Hajime*; Kondo, Shuji; Kanazawa, Shuhei; Ochi, Yoshihiro; Tanaka, Momoko; et al.
no journal, ,
We report on a femtosecond high-intensity OPCPA/Ti:sapphire hybrid laser system that produces more than 30 J broadband output energy, indicating the potential for achieving petawatt-class peak powers. High temporal-contrast of 10 to 10 has been obtained with a near-perfect flat-topped spatial-profile of filling factor 80%. We also present a compact, high-intensity OPCPA/Yb:YAG hybrid laser system that generates 100 mJ output energy with a temporal contrast of better than 10 and good spatial beam quality.
Yamaguchi, Hiromi; Miyamoto, Yasuaki; Sakakibara, Tetsuro; Hanamoto, Yukio; Aoyama, Yoshio; Sasaki, Nao*; Nishikawa, Tsutomu*; Murata, Minoru*; Muroi, Masayuki*; Park, J.*; et al.
no journal, ,
no abstracts in English
Sakaki, Hironao; Fukuda, Yuji; Kanasaki, Masato; Jinno, Satoshi; Yogo, Akifumi; Nishiuchi, Mamiko; Kando, Masaki; Ueno, Masayuki; Fukami, Tomoyo; Niita, Koji*
no journal, ,
The compact ion particle accelerator has become attractive in view of recent progress in laser-driven ions acceleration. In the development of the instrument, it is necessary to do the bench-mark of the amount of the different types of radiation by the simulation code for radiation shieldings. The Monte Carlo Particle and Heavy Ion Transport code (PHITS) was used for bench-mark the dose on the laser-driven cluster-target type accelerator.
Fukuda, Kenji; Murakami, Hiroaki; Itai, Kaori*; Ishibashi, Masayuki; Sasao, Eiji
no journal, ,
Matrix diffusion is one of the important for evaluating solute transport in granite. Diffusion of ions in granite pore water was studied in order to evaluate diffusivity in rock. Effective diffusion coefficient of uranine was measured using a diffusion cell. The effective diffusion coefficient of uranine in granite without fissure and alteration was found to be in the range 10 to 10 m s. The porosities of the granite samples were determined by observation of petrographic thin sections using entity fluorescence microscope. There was a positive correlation between the porosity larger than 1% and the effective diffusion coefficient.
Kiriyama, Hiromitsu; Ochi, Yoshihiro; Mori, Michiaki; Tanaka, Momoko; Okada, Hajime; Kosuge, Atsushi; Yoshida, Fumiko; Shimomura, Takuya; Sasao, Hajime; Nakai, Yoshiki*; et al.
no journal, ,
We describe two specific high intensity laser systems that are being developed in our laboratory for many applications such as high field science and nonlinear optics. We report on an ultra-high intensity petawatt-class Ti:sapphire chirped-pulse amplification laser system that can produce a pulse energy of 18 J with 30 fs pulse duration for studying extremely high intensity laser matter interaction process and a small-scaled Yb:YAG chirped-pulse amplification laser system that can generate a pulse energy of 100 m J of 500 fs pulse duration for compact, high efficiency, high repetition system. We discuss the basic design aspects and present the results from our experimental investigations of these laser systems.
Yamaguchi, Hiromi; Miyamoto, Yasuaki; Sakakibara, Tetsuro; Hanamoto, Yukio; Aoyama, Yoshio; Sasaki, Nao*; Nishikawa, Tsutomu*; Murata, Minoru*; Muroi, Masayuki*; Park, J.*; et al.
no journal, ,
no abstracts in English
Aoyama, Yoshio; Yamaguchi, Hiromi; Miyamoto, Yasuaki; Sakakibara, Tetsuro; Hanamoto, Yukio; Sasaki, Nao*; Nishikawa, Tsutomu*; Murata, Minoru*; Muroi, Masayuki*; Park, J.*; et al.
no journal, ,
no abstracts in English
Sasao, Eiji; Ishibashi, Masayuki; Murakami, Hiroaki; Fukuda, Kenji; Itai, Kaori*; Yuguchi, Takashi*
no journal, ,
The authors perform study on mass transport in granitic rock founded by JAEA "Hougakenkyu". In this poster, we report recent progress of our study.