Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
樋口 雄紀*; 吉宗 航*; 加藤 悟*; 日比 章五*; 瀬戸山 大吾*; 伊勢川 和久*; 松本 吉弘*; 林田 洋寿*; 野崎 洋*; 原田 雅史*; et al.
Communications Engineering (Internet), 3, p.33_1 - 33_7, 2024/02
The automotive industry aims to ensure the cold-start capability of polymer electrolyte fuel cells (PEFCs) for developing fuel cell electric vehicles that can be driven in cold climates. Water and ice behavior is a key factor in maintaining this capability. Previously reported methods for visualizing water and/or ice are limited to small-sized PEFCs ( 
50 cm
), while fuel cell electric vehicles are equipped with larger PEFCs. Here, we developed a system using a pulsed spallation neutron beam to visualize water distribution and identify water/ice phases in practical-sized PEFCs at a cold start. The results show direct evidence of a stepwise freezing behavior inside the PEFC. The produced water initially accumulated at the center of the PEFC and then froze, followed by PEFC shutdown as freezing progressed. This study can serve as a reference to guide the development of cold-start protocols, cell design, and materials for next-generation fuel cell electric vehicles.
野崎 洋*; 近藤 広規*; 篠原 武尚; 瀬戸山 大吾*; 松本 吉弘*; 佐々木 厳*; 伊勢川 和久*; 林田 洋寿*
Scientific Reports (Internet), 13, p.22082_1 - 22082_8, 2023/12
被引用回数：0 パーセンタイル：0(Multidisciplinary Sciences)Lithium ion batteries (LIBs) have become essential components that power most current technologies, thus making various safety evaluations necessary to ensure their safe use. Heating tests remain the most prominent source of safety issues. However, information on the phenomena occurring inside batteries during heating has remained inaccessible. In this study, we demonstrate the first in situ neutron imaging method to observe the internal structural deformation of LIBs during heating. We developed an airtight Al chamber specially designed to prevent radioactive contamination during in situ neutron imaging. We successfully observed the liquid electrolyte fluctuation inside a battery sample and the deformation of the protective plastic film upon heating up to thermal runaway.
吉宗 航*; 樋口 雄紀*; 加藤 晃彦*; 日比 章五*; 山口 聡*; 松本 吉弘*; 林田 洋寿*; 野崎 洋*; 篠原 武尚; 加藤 悟*
ACS Energy Letters (Internet), 8(8), p.3485 - 3487, 2023/08
被引用回数：2 パーセンタイル：52.07(Chemistry, Physical)A multiscale water visualization technique for polymer electrolyte fuel cells was established by using 
multiprobe radiography with pulsed spallation neutron and synchrotron X-ray sources. The three-dimensional water distribution revealed that water back-diffusion from the cathode to the anode significantly contributes to the drainability of practical polymer electrolyte fuel cells toward fuel cell electric vehicles.
那須 三紀*; 谷内 浩*; 平山 尚樹*; 安達 宏法*; 柿澤 優*; 白勢 裕登*; 西山 博道*; 川本 鉄平*; 犬飼 潤治*; 篠原 武尚; et al.
Journal of Power Sources, 530, p.231251_1 - 231251_11, 2022/05
被引用回数：16 パーセンタイル：89.77(Chemistry, Physical)To accelerate the spread use of polymer electrolyte fuel cells (PEFCs), it is essential to increase power density and durability, while reduce costs. We have succeeded in developing an innovative gas diffusion layer (GDL) with gas flow channels (GDLFC
) fabricated on a flat separator that enabled both cost reduction and high performance. In this study, neutron radiography was used to observe the distribution of liquid water during power generation. With using our GDLs and interdigitated (comb-shaped) gas flow channels, the distributions of liquid water were quantitatively imaged, influenced by the current density, the relative humidity, the oxygen utilization, and the water repellency of the GDL. The increase in linear velocity of the oxidant gases effectively suppressed the retention of liquid water at the cathode.
-dispersed LATP by means of neutron radiographySong, F.*; Chen, H.*; 林田 洋寿*; 甲斐 哲也; 篠原 武尚; 薮塚 武史*; 八尾 健*; 高井 茂臣*
Solid State Ionics, 377, p.115873_1 - 115873_6, 2022/04
被引用回数：2 パーセンタイル：31.08(Chemistry, Physical)Lithium tracer diffusion coefficients have been measured in Li
Al
Ti
(PO
)
(LATP) and LATP - LaPO composite solid electrolytes in the temperature range between 300
C and 500C by means of neutron radiography technique that utilizes the difference in neutron attenuation of 
Li and 
Li isotopes. The diffusion coefficient of LATP - LaPO composite is higher than that of pristine LATP, although the difference is much smaller than that estimated from the room temperature conductivity. This suggests that the bulk diffusion becomes the predominant diffusion mechanism at 300C to 500C instead of the diffusion along the space charge layer formed around the LaPO dispersants.
酒井 健二; 奥 隆之; 奥平 琢也; 甲斐 哲也; 原田 正英; 廣井 孝介; 林田 洋寿*; 加倉井 和久*; 清水 裕彦*; 広田 克也*; et al.
JPS Conference Proceedings (Internet), 33, p.011116_1 - 011116_6, 2021/03
中性子基礎物理学において、パリティ非保存(PNC)項や時間反転非保存項と干渉する中性子スピン
と標的核スピン
の相関項
は重要な研究テーマである。中性子共鳴ピーク付近でPNC項の増大が測定され、スピン交換光ポンピング(SEOP)法により
の偏極が得られるキセノン(Xe)は、本研究にとって興味深い原子核である。我々は小型SEOPシステムを用いた偏極Xe標的を開発し、核破砕中性子源で得られる大強度の熱外中性子ビームを利用した項の研究を計画している。その第一段階として、我々は
Xeの9.6eV共鳴ピーク付近でのXe偏極時と非偏極時の中性子透過率比の変化
を捕らえることで、項に起因する中性子偏極能力の測定をJ-PARC物質・生命科学実験施設(MLF)のBL10で試みた。実験では、本測定系がドップラーブロードニングの影響(
)を検知できることを実証した上で、初期結果として有意なの値を得ている。現在はをより詳細に評価するために、核磁気・電子スピン共鳴法によるXe偏極度の導出を進めている。
He neutron spin filter at J-PARC奥平 琢也; 奥 隆之; 猪野 隆*; 林田 洋寿*; 吉良 弘*; 酒井 健二; 廣井 孝介; 高橋 慎吾*; 相澤 一也; 遠藤 仁*; et al.
Nuclear Instruments and Methods in Physics Research A, 977, p.164301_1 - 164301_8, 2020/10
被引用回数：10 パーセンタイル：79.13(Instruments & Instrumentation)We are developing a neutron polarizer with polarized He gas, referred to as a He spin filter, based on the Spin Exchange Optical Pumping (SEOP) for polarized neutron scattering experiments at Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC). A He gas-filling station was constructed at J-PARC, and several He cells with long spin relaxation times have been fabricated using the gas-filling station. A laboratory has been prepared in the MLF beam hall for polarizing He cells, and compact pumping systems with laser powers of 30 W and 110 W, which can be installed onto a neutron beamline, have been developed. A He polarization of 85% was achieved at a neutron beamline by using the pumping system with the 110 W laser. Recently, the first user experiment utilizing the He spin filter was conducted, and there have been several more since then. The development and utilization of He spin filters at MLF of J-PARC are reported.
Parker, J. D.*; 原田 正英; 林田 洋寿*; 廣井 孝介; 甲斐 哲也; 松本 吉弘*; 中谷 健; 及川 健一; 瀬川 麻里子; 篠原 武尚; et al.
Materials Research Proceedings, Vol.15, p.102 - 107, 2020/05
At the RADEN instrument, we take advantage of the accurate measurement of neutron energy by time-of-flight to perform energy-resolved neutron imaging using event-type neutron imaging detectors. We are continually working to improve these detectors for better spatial resolution and shorter measurement times and, as a user facility, to improve the ease-of-use of their control and analysis software. In particular, we are actively developing a 
He-based gaseous micropattern detector known as the Micro-pixel chamber based Neutron Imaging Detector (
NID). We have recently redesigned the NID control software to allow full integration into the automated experiment control system at RADEN, and we are carrying out optimization of the analysis algorithms for improved image quality and rate performance.
篠原 武尚; 甲斐 哲也; 及川 健一; 中谷 健; 瀬川 麻里子; 廣井 孝介; Su, Y. H.; 大井 元貴; 原田 正英; 飯倉 寛; et al.
Review of Scientific Instruments, 91(4), p.043302_1 - 043302_20, 2020/04
被引用回数：51 パーセンタイル：96.48(Instruments & Instrumentation)The energy-resolved neutron imaging system, RADEN, has been installed at the pulsed neutron source in the Materials and Life Science Experimental Facility of the Japan Proton Accelerator Research Complex. In addition to conventional neutron radiography and tomography, RADEN, the world's first imaging beam-line at a pulsed neutron source, provides three main options for new, quantitative neutron imaging techniques: Bragg-edge imaging to visualize the spatial distribution of crystallographic information, resonance absorption imaging for elemental composition and temperature information, and polarized neutron imaging for magnetic field information. This paper describes the results of characterization studies of the neutronic performance and installed devices at RADEN and shows the results of several demonstration studies for pulsed neutron imaging.
He
excimer cluster tracers in superfluid helium-4 via neutron-He absorption reactionSonnenschein, V.*; 辻 義之*; 國立 將真*; 久保 渉*; 鈴木 颯*; 富田 英生*; 鬼柳 善明*; 井口 哲夫*; 松下 琢*; 和田 信雄*; et al.
Review of Scientific Instruments, 91(3), p.033318_1 - 033318_12, 2020/03
被引用回数：0 パーセンタイル：0(Instruments & Instrumentation)For the purpose of future visualization of the flow field in superfluid helium-4, clusters of the triplet state excimer He are generated along the micro-scale recoil tracks of the neutron-absorption reaction n + He 
T + p. This reaction is induced by neutron irradiation of the He fraction contained in natural isotopic abundance liquid helium with neutron beams either from the Japan Proton Accelerator Research Complex, Materials and Life Science Experimental Facility (J-PARC)/Materials and Life Science Experimental Facility or from the Kyoto University Institute for Integrated Radiation and Nuclear Science. These He clusters are expected to be ideal tracers of the normal-fluid component in superfluid helium with several advantageous properties. Evidence of the excimer generation is inferred by detection of laser induced fluorescence emitted from the He clusters excited by a purpose-built short pulse gain-switched titanium:sapphire (Ti:sa) laser operating at a wavelength of 905 nm. The setup and performance characteristics of the laser system including the Ti:sa and two continuous wave re-pumping lasers are described. Detection at the fluorescence wavelength of 640 nm is performed by using optical bandpass filtered photomultiplier tubes (PMT). Electrical noise in the PMT acquisition traces could successfully be suppressed by post-processing with a simple algorithm. Despite other laser-related backgrounds, the excimer was clearly identified by its fluorescence decay characteristics. Production of the excimer was found to be proportional to the neutron flux, adjusted via insertion of different collimators into the neutron beam. These observations suggest that the apparatus we constructed does function in the expected manner and, therefore, has the potential for groundbreaking turbulence research with superfluid helium.
甲斐 哲也; 廣井 孝介; Su, Y. H.; 瀬川 麻里子; 篠原 武尚; 松本 吉弘*; Parker, J. D.*; 林田 洋寿*; 及川 健一
Materials Research Proceedings, Vol.15, p.149 - 153, 2020/02
A two-dimensional thermometry technique based on neutron resonance reactions derives the temperature of specified elements in an object by analyzing the Doppler broadening of a neutron resonance measured by a time-analyzing neutron imaging-detector. This technique is expected to be one of the important applications of the energy-resolved neutron imaging system, RADEN, at J-PARC. The authors focused on molybdenum contained in 316 stainless-steel (with a weight fraction of 2-3 wt%). Energy-dependent transmitted neutrons were measured through a 3 mm thick 316 stainless-steel plate placed in a heater at temperatures between 23 and 500 degrees Celsius at RADEN using a gas-electron multiplier (GEM) detector. Thermal and cold neutrons were eliminated from the incident beam by a cadmium filter. The sample area within the neutron beam was 30 by 50 mm
. The feasibility is discussed in the presentation.
奥平 琢也; 奥 隆之; 酒井 健二; 猪野 隆*; 林田 洋寿*; 廣井 孝介; 篠原 武尚; 加倉井 和久*; 相澤 一也; 清水 裕彦*; et al.
Proceedings of Science (Internet), 356, p.029_1 - 029_5, 2019/12
共通技術開発セクションでは、J-PARC物質・生命科学実験施設の大強度中性子を活用するために、偏極中性子デバイスの一つであるHeスピンフィルターの開発を行なっている。Heスピンフィルターの性能評価の一つの手段に、基礎物理分野での応用・評価があり、基礎物理実験も活用している。現在の物質優勢宇宙を説明するためには時間反転対称性の破れが不可欠であり、世界中で時間反転対称性の破れの探索実験が行われている。その一つに偏極中性子と原子核を使用して対称性の破れを測定する方法があり、J-PARCの大強度中性子を用いた時間反転対称性の破れ探索が計画されている。本計画では1eV程度のエネルギーの高い中性子を偏極するための従来にない巨大なHeスピンフィルターを開発する必要があり、原子力機構にて開発が行われているHeスピンフィルターの性能評価の良い検証となる。現在、偏極率の精度の良い評価システムやHeスピンフィルター製作のための真空システムの構築を行い、熱外中性子偏極のための大型スピンフィルターの開発を継続している。本発表ではHeスピンフィルターの開発の現状について発表する。
清水 一行*; 林田 洋寿*; 戸田 裕之*; 甲斐 哲也; 松本 吉弘*; 松本 佳久*
日本金属学会誌, 83(11), p.434 - 440, 2019/11
被引用回数：1 パーセンタイル：6.23(Metallurgy & Metallurgical Engineering)Neutron imaging experiment was performed to visualize the distribution of solute hydrogen in an Al-10.1%Zn-1.2%Mg alloy and a pure palladium after hydrogen charging. Changes in the contrast of neutron transmission images caused by hydrogen were clearly observed in a palladium. In the wavelength range of 2-3 AA and 5-13.5 AA, the mean neutron transmission around the center of a hydrogen-charged palladium were 0.692 and 0.511, respectively. The hydrogen content in a palladium was estimated to be 10.8 mol% from the measured neutron transmission. This study has demonstrated that hydrogen content can be analyzed by considering the wavelength dependence of neutron intensity. On the other hand, hydrogen could not be observed from the neutron transmission image in Al-Zn-Mg alloys. This was due to the low hydrogen content, which was mass ppm level even after hydrogen charging, and statistical precision was not sufficient to discuss the amount of hydrogen of the mass ppm order.
He
clusters via neutron-He absorption reaction toward visualization of full velocity field in quantum turbulence松下 琢*; Sonnenschein, V.*; Guo, W.*; 林田 洋寿*; 廣井 孝介; 広田 克也*; 井口 哲夫*; 伊藤 大介*; 北口 雅暁*; 鬼柳 善明*; et al.
Journal of Low Temperature Physics, 196(1-2), p.275 - 282, 2019/07
被引用回数：1 パーセンタイル：4.76(Physics, Applied)For flow visualization study of quantum turbulence in superfluid He, He excimers are unique tracers which follow only normal-fluid component flow above 1 K. To generate detectable small He clouds (clusters) required for full-space velocity field measurements, we have adopted a new method based on neutron absorption reaction of He impurities in He and conducted proof-of-principle experiments. Generation of the He excimers was detected by laser-induced fluorescence using photomultiplier tubes. The fluorescence was observed to increase proportionally to the neutron flux, suggesting that a sufficient amount of He excimers were generated by neutrons. We also estimated the number of He excimers possibly generated by 
-rays and found that the relevant contribution was less than 40%. Thus, the majority of the He excimers was confirmed to be generated via n-He absorption reactions.
及川 健一; Su, Y.; 鬼柳 亮嗣; 川崎 卓郎; 篠原 武尚; 甲斐 哲也; 廣井 孝介; Harjo, S.; Parker, J. D.*; 松本 吉弘*; et al.
Physica B; Condensed Matter, 551, p.436 - 442, 2018/12
被引用回数：8 パーセンタイル：30.3(Physics, Condensed Matter)We are promoting for practical product observation by the energy-resolved neutron imaging method using high-intensity pulsed neutrons at J-PARC, under the Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan. Bragg edge imaging, one of the energy-resolved neutron imaging methods for visualizing material properties, was applied to feasibility study of the temperature distribution of copper rod, complementary study of the texture and strain distribution of bent steel plates using neutron diffraction and EBSD, and so on. Outline of results obtained by these imaging experiments will be presented.
廣井 孝介; 篠原 武尚; 林田 洋寿*; Parker, J. D.*; Su, Y.; 及川 健一; 甲斐 哲也; 鬼柳 善明*
Physica B; Condensed Matter, 551, p.146 - 151, 2018/12
被引用回数：5 パーセンタイル：25.82(Physics, Condensed Matter)Grain oriented magnetic steel is widely used as a key material for magnetic industrial products. Since magnetic properties of steels are closely related to its magnetic domain structure, observation of the domain structure is important for understanding its magnetic properties. In this study, we attempted to observe the domain structure of a grain oriented steel using polarized pulsed neutron imaging. In the experiment, we first magnetized the sample by applying a magnetic field along the easy-to-magnetize direction via a coil, and confirmed the sample was magnetized almost uniformly from the obtained polarization distribution images. By analyzing the oscillatory behavior in the wavelength dependence of polarization, magnetization of the steel was estimated to be 1.82 T. Then, we removed the field and performed the same measurement. As a result, a striped domain structure was observed, with neighboring domains aligned anti-parallel to each other. From these results, it was demonstrated that our magnetic imaging method could visualize the magnetization and the direction of the domains in the practical steel.
甲斐 哲也; 佐藤 節夫*; 廣井 孝介; Su, Y.; 瀬川 麻里子; Parker, J. D.*; 松本 吉弘*; 林田 洋寿*; 篠原 武尚; 及川 健一; et al.
Physica B; Condensed Matter, 551, p.496 - 500, 2018/12
被引用回数：2 パーセンタイル：10.36(Physics, Condensed Matter)The 2012 model lithium-6 time-analyzer neutron detector (LiTA12) system, based on a lithium glass scintillator and multi-anode photomultiplier tube, has the highest neutron efficiency among the detectors for pulsed neutron imaging together with a flexibility of the efficiency by changing the thickness of the lithium glass. The authors expect this detector system could become a main detector system for the energy-resolved neutron imaging system, RADEN, at J-PARC, and have started evaluation of the LiTA12 system. For example, spatial resolution for resonance absorption imaging was evaluated by using a line-pair pattern made by 3 micro meter thick gold on a quartz plate. Less than 1 mm width line pairs were resolved at an 8 Mcps neutron counting rate and around 5 eV neutron energy.
瀬川 麻里子; 及川 健一; 甲斐 哲也; 篠原 武尚; 林田 洋寿*; 松本 吉弘*; Parker, J. D.*; 中谷 健; 廣井 孝介; Su, Y.; et al.
JPS Conference Proceedings (Internet), 22, p.011028_1 - 011028_8, 2018/11
We have fabricated and utilized spatial resolution test targets made of gadolinium and gold for conventional and resonance neutron imaging performed at RADEN, located at beam line BL22 of the J-PARC Materials and Life Science Experimental Facility (MLF). RADEN covers a broad energy range from cold neutrons to high-energy neutrons with energy of several tens keV and was designed to perform energy-resolved neutron imaging utilizing two-dimensional detectors combined with the accurate measurement of neutron energy by the time-of-flight method. The test targets were designed to verify the spatial resolution and image uniformity of two kinds of neutron detectors, counting-type detectors and camera-type detectors. In this presentation, we report the details of these two-dimensional test targets, and the results of demonstrations using the test targets with our neutron imaging detectors. This work was supported in part by the Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
廣井 孝介; 篠原 武尚; 林田 洋寿*; Parker, J. D.*; 及川 健一; Su, Y.; 甲斐 哲也; 鬼柳 善明*
JPS Conference Proceedings (Internet), 22, p.011030_1 - 011030_7, 2018/11
We have been developing magnetic imaging method for industrial products using polarized pulsed neutrons. In this presentation, we report observation results of magnetic field distribution in a small electric transformer as a demonstration of our magnetic imaging method. The polarized pulsed neutron imaging experiment was performed at BL22 RADEN at MLF of J-PARC. 9 polarization distribution images were obtained with changing incident polarization and analyzing direction in 3D. By analyzing wavelength dependent polarization position by position, distribution of field strength and direction around the core of the transformer were successfully visualized. Obtained field distribution images were well corresponded with that expected by the simulation and clearly demonstrated a leaked field from the gap of step lap.
坂佐井 馨; 佐藤 節夫*; 瀬谷 智洋*; 中村 龍也; 藤 健太郎; 山岸 秀志*; 曽山 和彦; 山崎 大; 丸山 龍治; 奥 隆之; et al.
Quantum Beam Science (Internet), 1(2), p.10_1 - 10_35, 2017/09
J-PARC物質・生命科学実験施設では、中性子検出器、スーパーミラーやHeスピンフィルターなどの光学機器、及びチョッパー等の中性子デバイスが開発され、据え付けられている。また、計算環境として機器制御、データ取得、データ解析、及びデータベースの4つのコンポーネントが整備されている。また、物質・生命科学実験施設では実験に使用される様々な試料環境が利用可能である。本論文では、これらの現状について報告する。
