Zhang, J.*; Chen, M.*; Chen, J.*; Yamamoto, Kei; Wang, H.*; Hamdi, M.*; Sun, Y.*; Wagner, K.*; He, W.*; Zhang, Y.*; et al.
Nature Communications (Internet), 12(1), p.7258_1 - 7258_8, 2021/12
Wang, H.*; Yu, H.*; Kondo, Sosuke*; Okubo, Nariaki; Kasada, Ryuta*
Corrosion Science, 175, p.108864_1 - 108864_12, 2020/10
Corrosion tests were performed on newly developed alumina-forming austenitic (AFA) steels in stagnant lead bismuth eutectic (LBE) with saturated and low oxygen concentrations at 450C for 430 h. The steels exhibited enhanced corrosion resistance to the LBE environments with the increasing of Al content. A continuous and protective Al-rich oxide scale formed on the steel specimens that were exposed to LBE with a low oxygen concentration, whereas a non-protective and stratified oxide scale formed in the oxygen saturated LBE.
Fujihara, Masayoshi*; Morita, Katsuhiro*; Mole, R.*; Mitsuda, Setsuo*; Toyama, Takami*; Yano, Shinichiro*; Yu, D.*; Sota, Shigetoshi*; Kuwai, Tomohiko*; Koda, Akihiro*; et al.
Nature Communications (Internet), 11(1), p.3429_1 - 3429_7, 2020/07
Sun, M. D.*; Liu, Z.*; Huang, T. H.*; Zhang, W. Q.*; Andreyev, A. N.; Ding, B.*; Wang, J. G.*; Liu, X. Y.*; Lu, H. Y.*; Hou, D. S.*; et al.
Physics Letters B, 800, p.135096_1 - 135096_5, 2020/01
Li, B.*; Kawakita, Yukinobu; Kawamura, Seiko; Sugahara, Takeshi*; Wang, H.*; Wang, J.*; Chen, Y.*; Kawaguchi, Saori*; Kawaguchi, Shogo*; Ohara, Koji*; et al.
Nature, 567(7749), p.506 - 510, 2019/03
Refrigeration is of vital importance for modern society for example, for food storage and air conditioning- and 25 to 30% of the world's electricity is consumed for refrigeration. Current refrigeration technology mostly involves the conventional vapour compression cycle, but the materials used in this technology are of growing environmental concern because of their large global warming potential. As a promising alternative, refrigeration technologies based on solid-state caloric effects have been attracting attention in recent decades. However, their application is restricted by the limited performance of current caloric materials, owing to small isothermal entropy changes and large driving magnetic fields. Here we report colossal barocaloric effects (CBCEs) (barocaloric effects are cooling effects of pressure-induced phase transitions) in a class of disordered solids called plastic crystals. The obtained entropy changes in a representative plastic crystal, neopentylglycol, are about 389 joules per kilogram per kelvin near room temperature. Pressure-dependent neutron scattering measurements reveal that CBCEs in plastic crystals can be attributed to the combination of extensive molecular orientational disorder, giant compressibility and highly anharmonic lattice dynamics of these materials. Our study establishes the microscopic mechanism of CBCEs in plastic crystals and paves the way to next-generation solid-state refrigeration technologies.
Li, B.; Wang, H.*; Kawakita, Yukinobu; Zhang, Q.*; Feygenson, M.*; Yu, H. L.*; Wu, D.*; Ohara, Koji*; Kikuchi, Tatsuya*; Shibata, Kaoru; et al.
Nature Materials, 17(3), p.226 - 230, 2018/03
Ijiri, Yuta*; Ono, Naoko*; Ukai, Shigeharu*; Yu, H.*; Otsuka, Satoshi; Abe, Yosuke; Matsukawa, Yoshitaka*
Philosophical Magazine, 97(13), p.1047 - 1056, 2017/02
The interaction between oxide particles and dislocations in a 9Cr-ODS ferritic steel is investigated by both static and in-situ TEM observation under dynamic straining conditions and room temperature. The measured obstacle strength () of the oxide particles was no greater than 0.80 and the average was 0.63. The dislocation loops around some coarsened particles were also observed. The calculated obstacle strength by a stress formula of the Orowan interaction is nearly equaled to the average experimental value. Not only cross-slip system but also the Orowan interaction should be considered as the main interaction mechanism between oxide particles and dislocation in 9Cr-ODS ferritic steel.
Yu, R.*; Hojo, Hajime*; Watanuki, Tetsu; Mizumaki, Masaichiro*; Mizokawa, Takashi*; Oka, Kengo*; Kim, H.*; Machida, Akihiko; Sakaki, Koji*; Nakamura, Yumiko*; et al.
Journal of the American Chemical Society, 137(39), p.12719 - 12728, 2015/10
no abstracts in English
Kim, S. H.*; Hwang, S.; Ahn, J. K.*; Ekawa, Hiroyuki; Hayakawa, Shuhei; Hong, B.*; Hosomi, Kenji; Imai, Kenichi; Kim, M. H.*; Lee, J. Y.*; et al.
Nuclear Instruments and Methods in Physics Research A, 795, p.39 - 44, 2015/09
Sako, Hiroyuki; Ahn, J. K.*; Baek, K. H.*; Bassalleck, B.*; Fujioka, H.*; Guo, L.*; Hasegawa, Shoichi; Hicks, K.*; Honda, R.*; Hwang, S. H.*; et al.
Journal of Instrumentation (Internet), 9(4), p.C04009_1 - C04009_10, 2014/04
A TPC has been developed for J-PARC E42 experiment to search for H-dibaryon in (, ) reaction. An event with 2 and 2 protons decaying from H-dibaryon is searched for inside the TPC. The TPC has octagonal prism shape drift volume with about 50 cm diameter with 55 cm drift length filled with Ar-CH (90:10) gas. At the end of the drift volume, 3-layer GEMs are equipped. In order to analyze momenta of produced particles, the TPC is applied with 1 T dipole magnetic field parallel to the drift electric field with a superconducting Helmholz magnet. In order to maximize the acceptance of H-dibaryon events, a diamond target is installed inside the TPC drift volume, in a cylindrical hole opened from the top to the middle of the drift volume. Since extremely high-rate beam is directly injected into the TPC drift volume to the target, a gating grid and GEMs are adopted to suppress positive-ion feedback.
Vostner, A.*; Pong, I.*; Bessette, D.*; Devred, A.*; Sgobba, S.*; Jung, A.*; Weiss, K.-P.*; Jewell, M. C.*; Liu, S.*; Yu, W.*; et al.
IEEE Transactions on Applied Superconductivity, 23(3), p.9500705_1 - 9500705_5, 2013/06
The ITER Cable-In-Conduit Conductor (CICC) used in the superconducting magnet system consists of a cable made of 300 to 1440 strands housed in a stainless steel tube (a.k.a. jacket or conduit). There are circular, square, as well as circle-in-square jackets, made of either a very low carbon AISI 316LN grade stainless steel or a high Mn austenitic stainless steel developed for ITER called JK2LB. Selected mechanical properties of the base material and weld joint were tested at room temperature and/or cryogenic temperatures ( 7 K). The Domestic Agencies (DAs) reference laboratories and the ITER-IO appointed reference laboratories, CERN and Karlsruhe Institute of Technology (KIT) performed mechanical tests. This paper will compare the test results (e.g. elongation to failure) from different laboratories.
Choi, I. W.*; Kim, I. J.*; Pae, K. H.*; Nam, K. H.*; Lee, C.-L.*; Yun, H.*; Kim, H. T.*; Lee, S. K.*; Yu, T. J.*; Sung, J. H.*; et al.
Applied Physics Letters, 99(18), p.181501_1 - 181501_3, 2011/11
We report the manufacturing of a thin foil target made of conjugated polymer, and the simultaneous observation of laser accelerated ions and second harmonic radiation, when irradiated with ultrahigh-contrast laser pulse at a maximum intensity of 410 W/cm. Maximum proton energy of 8 MeV is achieved along the target normal direction. Strong second harmonic with over 6% energy ratio compared to fundamental is emitted along the specular direction. Two-dimensional particle-in-cell simulations confirm the simultaneous generation of protons and high-order harmonics, which demonstrates the feasibility of applications requiring particle and radiation sources at once, effectively using the same laser and target.
Park, J. M.*; Murakami, Masanori*; Petty, C. C.*; Heidbrink, W. W.*; Osborne, T. H.*; Holcomb, C. T.*; Van Zeeland, M. A.*; Prater, R.*; Luce, T. C.*; Wade, M. R.*; et al.
Physics of Plasmas, 16(9), p.092508_1 - 092508_10, 2009/09
Neutral beam current drive (NBCD) experiments in DIII-D using vertically shifted plasmas to move the current drive away from the axis have clearly demonstrated robust off-axis NBCD. Time-dependent measurements of magnetic pitch angles by the motional Stark effect diagnostic are used to obtain the evolution of the poloidal magnetic flux, which indicates a broad off-axis NBCD profile with a peak at about half the plasma radius. In most cases, the measured off-axis NBCD profile is consistent with calculations using an orbit-following Monte-Carlo code for the beam ion slowing down including finite-orbit effects, provided there is no large-scale MHD activity such as Alfvn eigenmodes modes or sawteeth. Good agreement is found between the measured pitch angles and those from simulations using transport-equilibrium codes. Two-dimensional image of Doppler-shifted fast ion D light emitted by neutralized energetic ions shows clear evidence for a hollow profile of beam ion density, consistent with classical beam ion slowing down. The magnitude of off-axis NBCD is sensitive to the alignment of the beam injection relative to the helical pitch of the magnetic field lines. If the signs of B and I yield the proper helicity, both measurement and calculation indicate that the efficiency is as good as on-axis NBCD because the increased fraction of trapped electrons reduces the electron shielding of the injected ion current, in contrast with electron current drive schemes where the trapping of electrons degrades the efficiency. The measured off-axis NBCD increases approximately linearly with the injection power, although a modest amount of fast ion diffusion is needed to explain an observed difference in the NBCD profile between the measurement and the calculation at high injection power.
Murakami, Masanori*; Park, J. M.*; Petty, C. C.*; Luce, T. C.*; Heidbrink, W. W.*; Osborne, T. H.*; Prater, R.*; Wade, M. R.*; Anderson, P. M.*; Austin, M. E.*; et al.
Nuclear Fusion, 49(6), p.065031_1 - 065031_8, 2009/06
Modification of the two existing DIII-D neutral beam lines is planned to allow vertical steering to provide off-axis neutral beam current drive (NBCD) peaked as far off-axis as half the plasma minor radius. New calculations for a downward-steered beam indicate strong current drive with good localization off-axis so long as the toroidal magnetic field, BT, and the plasma current, Ip, point in the same direction. This is due to good alignment of neutral beam injection (NBI) with the local pitch of the magnetic field lines. This model has been tested experimentally on DIII-D by an injecting equatorially-mounted NBs into reduced size plasmas that are vertically displaced with respect to the vessel midplane. The existence of off-axis NBCD is evident in the changes seen in sawtooth behavior in the internal inductance. By shifting the plasma upward or downward, or by changing the sign of the toroidal field, measured off-axis NBCD profiles measured with motional Stark effect data and internal loop voltage show a difference in amplitude (40%-45%) consistent with predicted differences predicted by the changed NBI alignment with respect to the helicity of the magnetic field lines. The effects of NB injection direction relative to field line helicity can be large even in ITER: off-axis NBCD can be increased by more than 20% if the BT direction is reversed. Modification of the DIII-D NB system will strongly support scenario development for ITER and future tokamaks as well as providing flexible scientific tools for understanding transport, energetic particles and heating and current drive.
Lei, A. L.*; Cao, L. H.*; Yang, X. Q.*; Tanaka, Kazuo*; Kodama, Ryosuke*; He, X. T.*; Mima, Kunioki*; Nakamura, Tatsufumi; Norimatsu, Takayoshi*; Yu, W.*; et al.
Physics of Plasmas, 16(2), p.020702_1 - 020702_4, 2009/02
The fast electron propagation in an inverse cone target is investigated computationally and experimentally. Two-dimensional particle-in-cell simulation shows that fast electrons with substantial numbers are generated at the outer tip of an inverse cone target irradiated by a short intense laser pulse. These electrons are guided and confined to propagate along the inverse cone wall, forming a large surface current. The experiment qualitatively verifies the guiding and confinement of the strong electron current in the wall surface. The large surface current and induced strong field s are of importance for fast ignition related research.
Nishiuchi, Mamiko; Daido, Hiroyuki; Yogo, Akifumi; Orimo, Satoshi; Ogura, Koichi; Ma, J.-L.; Sagisaka, Akito; Mori, Michiaki; Pirozhkov, A. S.; Kiriyama, Hiromitsu; et al.
Physics of Plasmas, 15(5), p.053104_1 - 053104_10, 2008/05
High-flux energetic protons whose maximum energies are up to 4 MeV are generated by an intense femtosecond Titanium Sapphire laser pulse interacting with a 7.5, 12.5, and 25m thick Polyimide tape targets. The laser pulse energy is 1.7 J, duration is 34 fs, and intensity is 310Wcm. The amplified spontaneous emission (ASE) has the intensity contrast ratio of 410. The conversion efficiency from laser energy into proton kinetic energies of 3% is achieved, which is comparable or even higher than those achieved in the previous works with nanometer-thick targets and the ultrahigh contrast laser pulses (10).
Yamasaki, Chisato*; Murakami, Katsuhiko*; Fujii, Yasuyuki*; Sato, Yoshiharu*; Harada, Erimi*; Takeda, Junichi*; Taniya, Takayuki*; Sakate, Ryuichi*; Kikugawa, Shingo*; Shimada, Makoto*; et al.
Nucleic Acids Research, 36(Database), p.D793 - D799, 2008/01
Here we report the new features and improvements in our latest release of the H-Invitational Database, a comprehensive annotation resource for human genes and transcripts. H-InvDB, originally developed as an integrated database of the human transcriptome based on extensive annotation of large sets of fulllength cDNA (FLcDNA) clones, now provides annotation for 120 558 human mRNAs extracted from the International Nucleotide Sequence Databases (INSD), in addition to 54 978 human FLcDNAs, in the latest release H-InvDB. We mapped those human transcripts onto the human genome sequences (NCBI build 36.1) and determined 34 699 human gene clusters, which could define 34 057 protein-coding and 642 non-protein-coding loci; 858 transcribed loci overlapped with predicted pseudogenes.
Orimo, Satoshi; Nishiuchi, Mamiko; Daido, Hiroyuki; Yogo, Akifumi; Ogura, Koichi; Sagisaka, Akito; Li, Z.*; Pirozhkov, A. S.; Mori, Michiaki; Kiriyama, Hiromitsu; et al.
Japanese Journal of Applied Physics, Part 1, 46(9A), p.5853 - 5858, 2007/09
A laser-driven proton beam with a maximum energy of a few MeV is stably obtained using an ultra-short and high-intensity Titanium Sapphire laser. At the same time, keV X-ray is also generated at almost the same place where protons are emitted. Here, we show the successful demonstration of simultaneous proton and X-ray projection images of a test sample placed close to the source with a resolution of 10m, which is determined from the source sizes. Although the experimental configuration is very simple, the simultaneity is better than a few hundreds of ps. A CR-39 track detector and imaging plate, which are placed as close as possible to the CR-39, are used as detectors of protons and X-ray. The technique is applicable to the precise observation of microstructures.
Jeong, T.*; Choi, I. W.*; Sung, J. H.*; Kim, H.*; Hong, K.*; Yu, T.*; Kim, J.-H.*; Noh, Y.*; Ko, D.-K.*; Lee, J.*; et al.
Journal of the Korean Physical Society, 50(1), p.34 - 39, 2007/01
no abstracts in English
Daido, Hiroyuki; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Mori, Michiaki; Ma, J.-L.; Pirozhkov, A. S.; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
Proceedings of 7th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-PR 2007) (CD-ROM), p.77 - 79, 2007/00
We are developing a proton accelerator using an intense lasers with a focused intensity of 10 W/cm. To monitor proton energy spectra as well as plasma parameters at each laser shot, we are using real time detectors. The proton energy of MeV is stably obtained for applications.