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間宮 広明*; 寺田 典樹*; 廣井 孝介; 篠原 武尚; Sepehri-Amin, H.*
Journal of Applied Physics, 138(14), p.143904_1 - 14390_10, 2025/10
被引用回数：1 パーセンタイル：41.30(Physics, Applied)Neutron diffractometry plays a pivotal role in fundamental magnetism research, especially in determining magnetic structures. However, its application in practical magnetics was historically sparse due to the simplicity of ferromagnetic materials in conventional devices. Recent increase in utilization of materials with complex magnetic structures has introduced new challenges that necessitate advanced neutron techniques in applied magnetics. This study investigates the applicability of neutron Bragg-edge spectroscopy for developing practical magnetic materials, substantiating its effectiveness through experimental validations and theoretical analysis. We discuss the principles of Bragg-edge spectroscopy for magnetic materials and highlight enhanced experimental throughput using multisample transmission spectroscopy. The study provides insights into the in situ visualization of magnetic state distribution using Bragg-edge imaging, both post-assembly and during operational use. These results indicate that neutron Bragg-edge spectroscopy can address emerging needs in applied magnetics, offering significant advancements in the field.
阿部 洋*; Maruyama, Shusei*; 廣井 孝介; 高田 慎一
Journal of Molecular Liquids, 404, p.124952_1 - 124952_8, 2024/06
被引用回数：1 パーセンタイル：12.86(Chemistry, Physical)In this study, phase variations within a hydrophilic ionic liquid (IL) - D
O mixture were observed in using small- and wide-angle neutron scattering (SWANS). The specific IL used was 1-dodecyl-3-methylimidazolium iodide ([C
mim][I]). Owing to the large neutron scattering length density of deuterium, DO nanostructures appeared to be enhanced in the SWANS profile. Moreover, the complicated phase diagram of [Cmim][I] - DO was determined using SWANS. Evidently, the water-rich region featured nanoconfined water (a water pocket), a smectic A phase, a columnar hexagonal phase as a lyotropic mesophase, a bicontinuous cubic phase as a double gyroid, and a layered crystal phase. Additionally, a double gyroid structure appeared in the narrow water-concentration region.
熊田 高之; 中川 洋; 三浦 大輔; 関根 由莉奈; 元川 竜平; 廣井 孝介; 稲村 泰弘; 奥 隆之; 大石 一城*; 森川 利明*; et al.
波紋, 34(2), p.50 - 53, 2024/05
本研究では、スピンコントラスト変調小角散乱法を用いてグルコース濃厚糖溶液を急冷すると氷結晶は平面上になり、その厚みは氷晶生成臨界半径と同程度の数ナノメートルしかないことを明らかにした。本研究は、グルコース分子が氷結晶の特定面に付着してその方向の成長を完全に止めてしまうことを示唆している。
齋藤 隼輝*; Yu, H.*; Gao, Z.*; 井上 耕治*; 近藤 創介*; 笠田 竜太*; 永井 康介*; 大場 洋次郎*; 廣井 孝介
Journal of Alloys and Compounds, 983, p.173852_1 - 173852_12, 2024/05
被引用回数：8 パーセンタイル：70.99(Chemistry, Physical)Cu alloys with high durability and high thermal and electric conductivities are the key to achieving a more energetically efficient and eco-friendly future. Noble Zr-added oxide-dispersion-strengthened Cu alloys (ODS - Cu) with high strengths are promising materials for meeting all future service requirements. In this study, three-dimensional atom probe (3D - AP) and transmission electron microscopy (TEM) revealed that the majority of nano - oxide particles in the Zr-added ODS - Cu were novel yttria-stabilized zirconia (YSZ) particles with a diameter of less than 4 nm, which were completely different from YZrO
and Y
Zr
O observed in other Zr - added ODS alloys. Multiscale observations including small - angle X - ray scattering (SAXS), 3D - AP, and TEM were performed to clarify the morphology of the oxide particles in the Zr - added ODS - Cu. Further strength enhancement through microstructural homogenization and specific incremental strength values were proposed.
関根 由莉奈; 南川 卓也; 廣井 孝介; 大場 洋次郎*; 永川 栄泰*; 杉田 剛; 柴山 由樹; 深澤 倫子*
Carbohydrate Polymers, 327, p.121538_1 - 121538_11, 2024/03
被引用回数：20 パーセンタイル：91.36(Chemistry, Applied)セルロースの結晶転移とその後の凍結架橋反応によってナノセルロース(NC)から形成された、無毒で強靱なNCゲルを開発した。低濃度のNaOHの使用と凍結を併用すると、凍結濃縮によりセルロースIからIIへのNCの結晶相転移が誘導されることを見出した。結晶相転移後、凍結濃縮層(FCL)内のNCとCA間の架橋により、強力なNCネットワーク構造が形成され、高い機械的強度を備えたNCハイドロゲルが形成した。凍結架橋したNCハイドロゲルは、NC-NaOHゾルと粉末吸着剤を混合することにより吸着剤を内部空間に容易に保持し、高い重金属除去効率を示した。この結果は、機能性材料の開発における化学修飾されていないセルロースの多用途性を示し、実用化の可能性を示すものである。
He spin filter and small-angle X-ray scattering領木 研之*; 渡部 史*; 奥平 琢也*; 高橋 慎吾*; 奥 隆之; 廣井 孝介; 元川 竜平; 中村 洋*
Journal of Chemical Physics, 160(11), p.114907_1 - 114907_9, 2024/03
被引用回数：2 パーセンタイル：28.62(Chemistry, Physical)Small-angle neutron scattering (SANS) and small-angle X-ray scattering (SAXS) measurements were performed for deuterated and non-deuterated poly(ethylene glycol) (d-PEG and h-PEG, respectively) in DO and a DO/HO mixed solvent (Mix) to compere the scattering profiles. To determine the coherent scattering intensity of SANS, a He spin filter was utilized. The scattering profiles determined by SANS measurements were analyzed in terms of the wormlike chain model with touched beads along the contour of the chain. However, the SAXS profiles were not explained by the same model with uniform beads but with beads each consisting of a core and a shell having different electron densities. To explore the chain thickness determined form the SANS profile, scattering intensities for different combinations of d-PEG/DO, d-PEG/Mix, h-PEG/DO, and h-PEG/Mix were also examined.
南川 卓也; 関根 由莉奈; 松村 大樹; 廣井 孝介; 高田 慎一; 神谷 嘉美*; 本多 貴之*
Langmuir, 40(11), p.5725 - 5730, 2024/03
被引用回数：2 パーセンタイル：21.30(Chemistry, Multidisciplinary)鉄と漆の化学反応を利用して、古くから黒漆が作られている。しかし、鉄と漆の反応については、ほとんど知られていない。本研究では、黒漆中のFeイオンの化学状態を、XANES, EXAFS、SAXS, SANSおよびFT-IRを使用して調査した。Fe(II)またはFe(III)を生漆に添加し、空気乾燥,加熱、またはUV照射により黒漆フィルムを作成した。これらのサンプルのXANESスペクトルの測定結果から、最初に添加したFeの酸化状態に関係なく、サンプル内のFeイオンが3価の状態で存在していることが明らかとなった。また、すべてのフィルムサンプルのEXAFSスペクトルは同様の形状であったが、ピーク強度は、空気乾燥
UV照射加熱の順に減少した。この結果は、加熱やUV照射により黒漆中のFeの配位構造が不均一になり、加熱が最も不均一になったことを示している。サンプルのFT-IRスペクトルの変化は、ウルシオールの重合挙動が空気乾燥,加熱、およびUV照射下でも異なり、漆中での反応により、Feの配位構造が不均一になることが明らかとなった。このような結果から、XANESやEXAFSスペクトルは、黒漆の情報を簡易に得る手法として有用であり、貴重な文化財の黒漆の非破壊分析に特に有効である。
土田 紀之*; Kuramoto, Shota*; 上路 林太郎*; Gong, W.; Harjo, S.; 廣井 孝介; 河村 幸彦*
ISIJ International, 64(2), p.354 - 360, 2024/01
被引用回数：0 パーセンタイル：0.00(Metallurgy & Metallurgical Engineering)The effects of pre-strain on the mechanical properties of high strength martensitic steels were investigated using either strain tempering (ST) or quenching and tempering (QT) samples. In the tensile tests at deformation temperatures between 296 and 573 K, the ST sample exhibited an increase in both the tensile strength (TS) and uniform elongation (U El) at 473 to 523 K, whereas the QT sample showed an increase in U El with little change in the TS and yield strength (YS). The results of in situ neutron diffraction experiments revealed an increase in the stress partitioning to the bcc phase with an increase in the deformation temperature from 296 to 523 K. The difference in the phase stress between the bcc and cementite phases decreased with an increase in the temperature due to the decrease in the cementite strength. Pre-strain of 0.5% increased the YS at 296 K with a slight work hardening; the initial dislocation density (
) decreased at 523 K, but increased significantly after yielding, leading to a better combination of TS and U.El. The combination of pre-strain, tempering, and deformation temperatures caused the change in before deformation and the increase in after yielding of the martensitic steel.
熊田 高之; 元川 竜平; 大場 洋次郎; 中川 洋; 関根 由莉奈; Micheau, C.; 上田 祐生; 杉田 剛; 美留町 厚; 佐々木 未来; et al.
Journal of Applied Crystallography, 56(6), p.1776 - 1783, 2023/12
被引用回数：28 パーセンタイル：98.42(Chemistry, Multidisciplinary)既存のメイン検出器および高位置分解能フォトマル検出器に加えて新規に導入した前面検出器を組み合わせることにより、波数0.002nm
から6nmにわたる散乱を3つの光学機器配置により切れ目なく測定できるようになった。またグラフィカルユーザーインターフェースの導入と併せて装置のユーザビリティが大幅に向上した。
O/HO vapor generator for contrast-variation neutron scattering有馬 寛*; 高田 慎一; 笠井 聡*; 大内 啓一*; 森川 利明*; 宮田 登*; 宮崎 司*; 青木 裕之; 岩瀬 裕希*; 廣井 孝介; et al.
Journal of Applied Crystallography, 56(6), p.1802 - 1812, 2023/12
被引用回数：6 パーセンタイル：67.52(Chemistry, Multidisciplinary)The contrast-variation technique in neutron scattering experiments plays a pivotal role in distinguishing partial structures within multi-component complexes, facilitating the elucidation of distinct sample constituents. This differentiation is achieved using different isotopes, namely hydrogen and deuterium, which possess varying neutron scattering characteristics. This study presents a novel vapor generator designed for neutron scattering experiments, enabling continuous control of the DO/HO ratio of the vapor. This feature is especially useful for contrast-variation studies. The generator features two saturators and four mass flow controllers, allowing for the rapid and independent generation of DO/HO vapors. Additionally, the incorporation of the two-temperature method ensures accurate dew point control within a margin of 
0.2
Cdp. This setup proves useful for conducting time-resolved experiments and can accelerate research on functional polymers, such as polymer electrolyte membranes for fuel cells, where water potential assumes critical importance.
間宮 広明*; 大場 洋次郎; 寺田 典樹*; 廣井 孝介; 篠原 武尚
IEEE Transactions on Magnetics, 59(11), p.6500505_1 - 6500505_5, 2023/11
Neutron transmission spectroscopy is a promising characterization method. In addition, polarized neutrons provide further information via the detailed analysis of magnetic scattering contributions. In this study, we have investigated the contributions of ferrite, cementite, and retained austenite in an ultra-fine grained high carbon steel using the polarized neutron transmission spectroscopy. The polarized neutron transmission spectrum of the sample is well explained by the combination of ferrite and cementite and the amount of austenite can be ignored. This indicates that the polarized neutrons are helpful to evaluation of the complicated microstructures in carbon steels.
阿部 洋*; 根本 文也*; 廣井 孝介; 高田 慎一
Journal of Molecular Liquids, 386, p.122551_1 - 122551_7, 2023/09
被引用回数：6 パーセンタイル：51.71(Chemistry, Physical)Nanoconfined water (water pocket) and ionic liquid crystals (ILCs) were formed in a hydrophilic ionic liquid (IL)-DO system. Herein, 1-decyl-3-methylimidazolium nitrate ([C
mim][NO]) was used as the IL. By the complementary use of small- and wide-angle X-ray and neutron scattering, a complicated phase diagram of [Cmim][NO]-DO was determined. The lyotropic ILCs of [Cmim][NO] containing 70-90 mol% DO appeared at room temperature. At high temperature, the lyotropic ILCs transformed into the water pocket in the nanoheterogeneous liquid.
熊田 高之; 中川 洋; 三浦 大輔; 関根 由莉奈; 元川 竜平; 廣井 孝介; 稲村 泰弘; 奥 隆之; 大石 一城*; 森川 利明*; et al.
Journal of Physical Chemistry Letters (Internet), 14(34), p.7638 - 7643, 2023/08
被引用回数：1 パーセンタイル：6.30(Chemistry, Physical)スピンコントラスト変調中性子小角散乱法を用いて急冷したグルコース濃厚溶液中に生成するナノアイス結晶の構造解析を行ったところ、厚さ1nm程度、半径数十nm以上の平面上の氷晶が生成していることを見出した。本結果はグルコース分子が特定の成長面に吸着することによりその面からの結晶成長を阻害していることを示す。
間宮 広明*; 大場 洋次郎; 寺田 典樹*; 廣井 孝介; 大久保 忠勝*; 篠原 武尚
Scientific Reports (Internet), 13, p.9184_1 - 9184_8, 2023/06
被引用回数：3 パーセンタイル：19.75(Multidisciplinary Sciences)We have developed a neutron imaging technique to visualize magnetization vector inside magnetic devices. The result confirms that the magnetization vector circulates in a ferrite ring core assembled on an inductor with a ferrimagnetic spin order during operation. This experimental technique allows operando imaging of magnetic states to evaluate advanced magnetic devices using complex magnetic components.
Hibino, Masayuki*; 高田 慎一; 廣井 孝介; 青木 裕之; 寺島 崇矢*
Macromolecules, 56(8), p.2955 - 2964, 2023/04
被引用回数：9 パーセンタイル：51.99(Polymer Science)Amphiphilic random copolymers bearing poly(ethylene glycol) (PEG) and alkyl groups as side chains are intermolecularly self-assembled into size-controlled multichain micelles in water. The random copolymer micelles are known to induce the exchange of their polymer chains, whereas the details of the kinetics and mechanism have not been elucidated yet. Herein, we investigated the exchange kinetics and mechanism of the random copolymer chains between their micelles by time-resolved small-angle neutron scattering (TR-SANS). For this purpose, random copolymers carrying PEG and deuterated butyl or dodecyl groups were designed for deuterated micelles. After mixing deuterated and non-deuterated micelle solutions, the resulting mixtures were monitored by TR-SANS at various concentrations and temperatures. The scattering intensity of the micelle mixtures decayed with time, indicating that deuterated copolymers were gradually mixed with non-deuterated copolymers via chain exchange between their micelles to form micelles consisting of both deuterated and non-deuterated copolymers. The kinetic analysis revealed that the exchange of their polymer chains involved two mechanisms: A unimer release and insertion pathway was dominant in diluted conditions, whereas the contribution of a micelle collision pathway increased with increasing total polymer concentration and temperature. The activation energy of the polymer exchange process was dependent on the hydrophobic alkyl groups and larger than that of a related surfactant micelle.
O submicron spherical particles小林 悟*; 野村 英志*; 千葉 桃子*; 河村 幸彦*; 大石 一城*; 廣井 孝介; 鈴木 淳市*
Journal of Magnetism and Magnetic Materials, 569, p.170410_1 - 170410_9, 2023/03
被引用回数：3 パーセンタイル：19.75(Materials Science, Multidisciplinary)We report results of polarized small-angle and wide-angle neutron scattering experiments at 
= 10 and 300 K for 420 nm-sized hollow FeO spherical particles. Each hollow particle is a mesocrystal, which is composed of small nanoparticles with nearly the same crystallographic orientation. Polarized neutron experiments allow us to evaluate magnetic correlations of parallel and perpendicular magnetization components with respect to magnetic field during magnetization process. Small-angle neutron scattering reveals that as the magnetic field decreases from a saturation field of 10 kOe, the perpendicular magnetization component maximizes around zero applied field, whereas the parallel component minimizes. This behavior was observed below and above Verwey transition temperature of 
120 K. Calculations of neutron intensities for vortex structures suggest the reorientation of the vortex core towards the magnetocrystalline anisotropy axis from the magnetic field direction at low applied fields. Moreover, a magnetic domain length obtained from the wide-angle scattering is of the order of 30-40 nm and comparable to the size of the small nanoparticles forming a hollow sphere, suggesting that magnetic correlations within the small nanoparticles always retain during magnetization process.
大石 一城*; 五十嵐 大輔*; 多々良 涼一*; 河村 幸彦*; 廣井 孝介; 鈴木 淳市*; 梅垣 いづみ*; 西村 昇一郎*; 幸田 章宏*; 駒場 慎一*; et al.
Journal of Physics; Conference Series, 2462, p.012048_1 - 012048_5, 2023/03
被引用回数：2 パーセンタイル：93.04(Physics, Applied)Hard carbon is the most common anode material for Na-ion battery. The structure of the hard carbon and the dynamics of Na-ion in hard carbon were studied with small- and wide- angle neutron scattering and muon spin relaxation technique. The neutron scattering revealed the increase of interlayer distance between graphenes and decrease of the size of nanopores with increasing sodium intercalation in hard carbon. The muon spin relaxation revealed that a systematic increase in the field fluctuation rate with increasing temperature evidenced a thermally activated sodium diffusion. Assuming the two-dimensional diffusion of Na-ion in the graphene layers, the self-diffusion coefficient of Na-ion was estimated to be 2.6
10
cm
/s at 310 K, with a thermal activation energy of 39(7) meV.
間宮 広明*; 大場 洋次郎; 廣井 孝介; 宮武 孝之*; Gautam, R.*; Sepehri-Amin, H.*; 大久保 忠勝*
IEEE Magnetics Letters, 14, p.7100105_1 - 7100105_5, 2023/02
被引用回数：2 パーセンタイル：16.84(Engineering, Electrical & Electronic)In nanocrystalline soft magnets, microscopic magnetic states inside the materials important for macroscopic soft magnetic properties. Therefore, we measured small-angle neutron scattering of the nanocrystalline soft magnets. The results clearly indicate the magnetic scattering of the nano-crystallized samples, while the as-quenched sample shows only featureless scattering. This provides essential information for the relationship between the magnetic nanostructures and the macroscopic magnetic softness.
三浦 大輔*; 関根 由莉奈; 南川 卓也; 杉田 剛; 大場 洋次郎; 廣井 孝介; 大澤 辰彦
Carbohydrate Polymer Technologies and Applications (Internet), 4, p.100251_1 - 100251_9, 2022/12
凍結架橋により形成されたカルボキシメチルセルロースナノファイバー(CMCF)ゲルの反応機構を調べた。異なる反応時間で調製されたCMCFヒドロゲルの物性評価により、凍結架橋反応中の階層構造変化の観察に成功した。凍結架橋CMCFヒドロゲルは、従来の方法で形成された通常のゲルとは異なり、オングストロームからマイクロメートルスケールまでの特徴的な階層構造を示し、その特異的構造が飛躍的な力学強度の向上に寄与していることを明らかにした。
O
submicron particles studied by polarized small-angle neutron scattering野村 英志*; 千葉 桃子*; 松尾 咲琴*; 野田 千晶*; 小林 悟*; Manjanna, J.*; 河村 幸彦*; 大石 一城*; 廣井 孝介; 鈴木 淳市*
AIP Advances (Internet), 12(3), p.035034_1 - 035034_5, 2022/03
被引用回数：5 パーセンタイル：31.47(Nanoscience & Nanotechnology)We report results of polarized small-angle neutron scattering (SANS) experiments at T = 10 K and 300 K for cubic FeO submicron- sized particles, where formation of a complex spin vortex is expected. Magnetic SANS intensities of magnetization components in the direction perpendicular and parallel to the magnetic field were observed to change significantly at around the coercivity. Magnetization components parallel to the field minimizes around the coercivity both at T = 10 K and 300 K, whereas those perpendicular to the magnetic field maximizes near the coercivity and the maximum value differ greatly, depending on the temperature. Based on results of micromagnetic simulations, the observed SANS intensities were interpreted as due to magnetic structural changes from a flower to a spin vortex state and gradual tilting of a vortex core from the external field to magnetocrystalline anisotropy axes at low fields.
