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Katsumi, Toshiyuki; Yoshida, Yasuhito*; Nakagawa, Ryo*; Yazawa, Shinya*; Kumada, Masashi*; Sato, Daisuke*; Thwe Thwe, A.; Chaumeix, N.*; Kadowaki, Satoshi
Journal of Thermal Science and Technology (Internet), 16(2), p.21-00044_1 - 21-00044_13, 2021/00
Times Cited Count：5 Percentile：36.79(Thermodynamics)The effects of addition of CO
and water vapor on characteristics of dynamic behavior of hydrogen/air premixed flames were elucidated experimentally. By Schlieren photography, wrinkles on the flame surface were clearly observed in low equivalence ratios. The propagation velocity increased monotonically as the flame radius became larger and flame acceleration was found. Increasing the addition of inert gas, the propagation velocity decreased, especially in the case of CO addition. Moreover, the Markstein length and the wrinkling factor decreased. This indicated that the addition of Co or HO promoted the unstable motion of hydrogen flames, which could be due to the enhancement of the diffusive-thermal effect. Based on the characteristics of dynamic behavior of hydrogen flames, the parameters used in the mathematical model on propagation velocity including flame acceleration was obtained, and then the flame propagation velocity under various conditions was predicted.
Kubota, Tomohiro; Kuroda, Hisao*; Watanabe, Mirai*; Takahashi, Akiko*; Nakazato, Ryoji*; Tarui, Mika*; Matsumoto, Shunichi*; Nakagawa, Keita*; Numata, Yasuko*; Ouchi, Takao*; et al.
Atmospheric Environment, 243, p.117856_1 - 117856_9, 2020/12
Times Cited Count：3 Percentile：15.82(Environmental Sciences)The dry and wet depositions of atmospheric ammonia (NH
) is one of the important pathways of nitrogen loads to aquatic ecosystems. Crop and livestock agriculture, one of the largest emitters of NH in Asian countries, are known to cause high spatial and seasonal variation of NH and influence the surrounding lake basin areas via its dry and wet deposition. However, the spatial characteristics of the NH concentration in basin scale are not completely understood for regulation in NH emission. Here we aim to clarify dominant factors of spatial and seasonal variations of the NH concentration in a eutrophic lake basin surrounded by agricultural areas in Japan. Passive sampling over various land use categories in the basin was conducted at 36 sites in total from October 2018 to January 2020. Interestingly, the observed NH concentration near the livestock houses were higher in winter than summer, which was inconsistent with knowledge of seasonal changes of current NH emission inventory based on temperature-driven volatilization process. Comparing monthly NH concentrations with various meteorological factors, we suggested the importance of seasonal advection of NH from high emission sources to which has been rarely paid attention by the previous past studies. As for this, should be considered for lake ecosystem management since deposition of NH is known to be closely related to the ecological processes such as phytoplankton blooming.
Seto, Hideki; Ito, Shinichi; Yokoo, Tetsuya*; Endo, Hitoshi*; Nakajima, Kenji; Shibata, Kaoru; Kajimoto, Ryoichi; Kawamura, Seiko; Nakamura, Mitsutaka; Kawakita, Yukinobu; et al.
Biochimica et Biophysica Acta; General Subjects, 1861(1), p.3651 - 3660, 2017/01
Times Cited Count：32 Percentile：80.67(Biochemistry & Molecular Biology)J-PARC, Japan Proton Accelerator Research Complex provides short pulse proton beam at a repetition rate 25 Hz and the maximum power is expected to be 1 MW. Materials and Life Science Experimental Facility (MLF) has 23 neutron beam ports and 21 instruments have already been operated or under construction / commissioning. There are 6 inelastic / quasi-elastic neutron scattering spectrometers and the complementary use of these spectrometers will open new insight for life science.
collisions at 
= 200 and 62.4 GeVAdare, 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.
and Au+Au collisions at 
= 200 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.
Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04
Times Cited Count：8 Percentile：49.7(Physics, Nuclear)Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.
-rays; Guineagrass and sorghumNakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 72, 2008/03
no abstracts in English
Nakagawa, Sho*; Hori, Fuminobu*; Chimi, Yasuhiro; Ishikawa, Norito; Kitagawa, Michiharu*; Oshima, Ryuichiro*; Tobita, Toru; Taniguchi, Ryoichi*; Suzuki, Masahide; Iwase, Akihiro*
Nuclear Instruments and Methods in Physics Research B, 257(1-2), p.397 - 401, 2007/04
Times Cited Count：4 Percentile：35.71(Instruments & Instrumentation)Supersaturated Fe-1.2wt.%Cu alloys were irradiated with 200-MeV Xe and 200-MeV Au ions at elevated temperatures. To make an irradiated region and an unirradiated region in a specimen, a masking plate was put on the specimen during the irradiation. After the irradiation, the hardness was measured by using a conventional microhardness tester or a nano-indenter. We have found that the hardness only in irradiated region increases by the irradiation. The boundary of irradiated and unirradiated regions can be clearly identified by the difference in hardness. The present result implies that swift heavy ion irradiation can be used for the local modification of hardness in supersaturated alloys.
rayMorita, Ryohei*; Morishita, Toshikazu*; Nakagawa, Hitoshi*; Nishimura, Minoru*; Yamaguchi, Hiroyasu*; Yokota, Yuichiro; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 78, 2007/02
no abstracts in English
Tsuchiya, Bun*; Teshigawara, Makoto; Nagata, Shinji*; Konashi, Kenji*; Yasuda, Ryo; Nishino, Yasuharu; Nakagawa, Tetsuya*; Yamawaki, Michio*
Nuclear Instruments and Methods in Physics Research B, 190(1-4), p.699 - 703, 2002/05
Times Cited Count：10 Percentile：54.86(Instruments & Instrumentation)Practicability of Elastic Recoil Detection (ERD) and Neutron Radiography (NRG) methods for hydrogen concentration in titanium hydrides (d-TiHx : 1.6<x<2.0) is investigated. In ERD methods, the hydrogen concentration in the surface of TiHx is recognized. In NRG method, the hydrogen concentration over the balk was confirmed. These results show that both methods are effective means for estimating the hydrogen concentration in hydride materials.
raysMorita, Ryohei*; Morishita, Toshikazu*; Nakagawa, Hitoshi*; Nishimura, Minoru*; Yamaguchi, Hiroyasu*; Yokota, Yuichiro; Hase, Yoshihiro; Tanaka, Atsushi
no journal, ,
no abstracts in English
ray; Guinea grass and sorghumNakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
no journal, ,
no abstracts in English
Nakatani, Takeshi; Inamura, Yasuhiro; Ito, Takayoshi; Kajimoto, Ryoichi; Aoyagi, Tetsuo; Ohara, Takashi; Otomo, Toshiya*; Yasu, Yoshiji*; Suzuki, Jiro*; Morishima, Takahiro*; et al.
no journal, ,
We have started the commissioning of the neutron scattering experiment instruments since May 2008 in MLF, J-PARC. Simultaneously, we have started the commissioning of the data acquisition and analysis software. Experimental users operate this software through the software framework which we have developed. The software framework was developed based on Python which is an object oriented script language. The system implemented with the software framework can seamlessly measure, analyze and visualize with some modules which are experimental control and data analysis. In this presentation, we report the process of the construction and the current status of the software.
Nakatani, Takeshi; Inamura, Yasuhiro; Ito, Takayoshi; Kajimoto, Ryoichi; Harjo, S.; Arai, Masatoshi; Ohara, Takashi; Nakagawa, Hiroshi; Aoyagi, Tetsuo; Otomo, Toshiya*; et al.
no journal, ,
We have developed the software framework in MLF computing environment from 2006 to 2008. The software framework is the fundamental software for neutron and muon experimental instruments in J-PARC/MLF. Currently, the software framework is installed at 4D Space Access Neutron Spectrometer (BL01), IBARAKI Biological Crystal Diffractometer (BL03), Cold-Neutron Disk-Chopper Spectrometer (BL14), Engineering Materials Diffractometer (BL19) and High Intensity Total Diffractometer (BL21). The features of experimental control, analysis, visualization and authorization are already implemented in the software framework. In this year, we will start the development to introduce the feature of database. We will present the current status and future plan of the software framework.
raysYamazaki, Takumi; Takada, Chie; Nakamura, Keisuke; Sagawa, Naoki; Hoshi, Katsuya; Nakagawa, Takahiro; Takimoto, Misaki; Tanimura, Yoshihiko*; Takahashi, Fumiaki; Momose, Takumaro; et al.
no journal, ,
no abstracts in English
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru*; Koga, Yuki*; Okamoto, Ryo*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo
no journal, ,
Tritium production method using HTGRs (High Temperature Gas-cooled reactors) is studied as the tritium supplying method for initial D-T fusion reactors. In this method, tritium is produced by 
Li (n,
)T reaction. The amount of tritium production and the tritium confinement capability were evaluated in case of the irradiation capsule including the Li compound is installed into the HTGRs in the past. In this study, the tritium confinement capability is evaluated for the irradiation capsule with ZrC layer by performing calculations of the amount of tritium leakage. The calculation results showed that the amount of tritium leakage is decreased to one fifth with the ZrC layer.
850
C) conditionsOkamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru; et al.
no journal, ,
Currently, many researches to achieve DT nuclear-fusion power generation are under proceeding but the method to provide initial tritium loaded to fusion prototype reactor is not clear. The method of tritium production by using high temperature gas-cooled reactor (HTGR) was proposed. In this method, lithium rods are loaded to the reactor core of HTGR and tritium is produced by Li(n,)T reaction. And the method to reduce the spilled tritium by using the lithium rod with zirconium layer was proposed. In this study, the experiments to evaluate the performance of hydrogen absorption in the zirconium layer were conducted under the temperature condition more than 700C which is the normal operation condition for the very high temperature gas-cooled reactor (VHTR). The experimental result concerning solubility and diffusion factor of hydrogen in the zirconium layer will be presented and discussed.
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru; Okamoto, Ryo*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. However, tritium is very rare and kg order of tritium must be produced artificially. Tritium production, by Li(n,)T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed. In this method, loading of Li rods into burnable poison (BP) holes in HTGR is considered. In this paper, the Li rod suited to the demand for the utilization in High Temperature engineering Test Reactor (HTTR) is designed, and tritium production and leakage from Li-rod capsule are evaluated by adjusting the thickness of LiAlO, alumina, and Zr layers. A scenario of irradiation test supposed to be conducted at HTTR for demonstration of the tritium production and containment performance of the Li rod is presented.
C) conditionsOkamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Suganuma, Takuro*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
It has been proposed that lithium rods, which are cylindrical lithium compounds, are loaded into a HTGR and tritium for initial fusion reactors is produced by Li(n,)T reaction. In this study, it was discussed that the lithium rods are covered with zirconium layers to prevent the produced tritium leak. The solubility and diffusion coefficient of hydrogen in zirconium were measured and the effectiveness of the zirconium layers on prevention of tritium leakage was estimated with the measured values. As a result, the tritium leakage ratio with the zirconium layers was estimated two orders lower than that without the zirconium layers, and hence it was considered that the zirconium layer is very effective on the prevention of the tritium leakage.
Koga, Yuki*; Matsuura, Hideaki*; Okamoto, Ryo*; Ida, Yuma*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. Tritium production, by Li(n, )T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed and the method to produce tritium by loading the lithium rods as burnable poison in the reactor core has been studied. In this presentation, the design of lithium rods to be loaded to High Temperature engineering Test Reactor (HTTR) and its irradiation test plan to demonstrate tritium production are presented.
Okamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru
no journal, ,
A study on tritium production using a high-temperature gas-cooled reactor has been carried out and it was proposed that zirconium is loaded into the lithium irradiation capsule to confine tritium within the irradiation capsule under high temperature condition. In this study, zirconium loading method was examined by numerical calculations to improve the tritium confinement. As a result, it was found that improvement in the tritium confinement can be expected by loading spherical zirconium into the irradiation capsule.
