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Structure analysis of a buried interface between organic and porous inorganic layers using spin-contrast-variation neutron reflectivity

熊田 高之; 三浦 大輔*; 阿久津 和宏*; 大石 一城*; 森川 利明*; 河村 幸彦*; 鈴木 淳市*; 奥 隆之; 鳥飼 直也*; 新関 智丈*

Journal of Applied Crystallography, 55(5), p.1147 - 1153, 2022/10

 被引用回数:0 パーセンタイル:0.01(Chemistry, Multidisciplinary)



Small-angle neutron scattering by spatially inhomogeneous ferromagnets with a nonzero average uniaxial anisotropy

Zaporozhets, V. D.*; 大場 洋次郎; Michels, A.*; Metlov, K. L.*

Journal of Applied Crystallography, 55(3), p.592 - 600, 2022/06

 被引用回数:5 パーセンタイル:95.38(Chemistry, Multidisciplinary)

Micromagnetic theory well explains the magnetic small-angle neutron scattering (SANS) data of bulk ferromagnets. However, only the samples having random magnetic anisotropy are mainly handled. In this study, the micromagnetic SANS theory is extended to allow to analyze uniaxial magnetic anisotropy. Micromagnetic response functions for SANS are computed analytically for several practical arrangements of anisotropy and external magnetic field orientations. This theory agrees well with the experimental SANS data of a practical soft magnet and plastically-deformed Ni and successfully provides the uniaxial anisotropy quality factors.


Optimization and inference of bin widths for histogramming inelastic neutron scattering spectra

巽 一厳; 稲村 泰弘; 古府 麻衣子; 鬼柳 亮嗣; 島崎 秀昭*

Journal of Applied Crystallography, 55(3), p.533 - 543, 2022/06

 被引用回数:0 パーセンタイル:0.01(Chemistry, Multidisciplinary)

神経物理学研究において不均一ポアソン過程に基づく観測データのヒストグラムのビン幅最適化が開発され[Shimazaki & Shinomoto (2007). Neural Comput. 19, 1503-1527]、後継研究[Muto et al. (2019). J. Phys. Soc. Jpn, 88, 044002]はその非弾性中性子散乱データへの応用が提唱された。本研究では、銅の単結晶を用いて異なる条件の飛行時間型計測で得られた非弾性中性子散乱の実験データにこの方法を適用し、その結果の正当性を検証した。与えられたデータにおける統計情報を異なる総カウント数のデータに外挿した結果は、それらの実際のデータでの最適なビン幅を精度よく予測した。最適化したビン幅でのヒストグラムはエネルギーおよび運動量の断面において次の二つの微細スペクトル構造の存在の有無を検視した。(1)フォノンバンドギャップの存在、(2)互いに隣接する複数のフォノンブランチの数。磁気励起の新奇な形態や講師熱伝導度に相関するフォノン状態等、物理や材料科学において重要なスペクトル構造を効果的かつ厳正に観測するのを今回適用した方法は助けることをこれは意味する。


Non-destructive characterization of the spatial variation of $$gamma$$/$$gamma$$$$^{'}$$ lattice misfit in a single-crystal Ni-based superalloy by energy-resolved neutron imaging

Malamud, F.*; Santisteban, J. R.*; Gao, Y.*; 篠原 武尚; 及川 健一; Tremsin, A.*

Journal of Applied Crystallography, 55(2), p.228 - 239, 2022/04

 被引用回数:1 パーセンタイル:0.01(Chemistry, Multidisciplinary)

Lattice misfit in nickel-based superalloys is one of the important microstructural parameters that control their mechanical properties, such as creep behaviour at high temperatures. Here, energy-resolved neutron imaging experiments are performed at a spallation neutron source to determine the spatial variation of lattice misfit on a second-generation nickel-based single-crystal superalloy specimen produced from a failed low-cycle fatigue specimen. An analysis of the position and width of those Laue peaks in the obtained transmission spectra allows determination of the lattice parameters of the $$gamma$$ and $$gamma$$$$^{'}$$ phases that compose the specimen, as well as the strain misfit and the misorientation between them. An analytical model is developed to describe the full wavelength pattern of Laue peaks arising from a specimen composed of two single crystals, and this model is used to perform least-squares refinements of the spectra measured at different positions of the specimen.


Evaluation of sample cell materials for aqueous solutions used in quasi-elastic neutron scattering measurements

富永 大輝*; 佐原 雅恵*; 川北 至信; 中川 洋; 山田 武*

Journal of Applied Crystallography, 54(6), p.1631 - 1640, 2021/12

 被引用回数:3 パーセンタイル:64.76(Chemistry, Multidisciplinary)

For quasi-elastic neutron scattering (QENS) studies, sample cells made of pure or alloyed aluminum are frequently employed. Although the Al surface is protected by a passivating film, this film is not robust. Therefore, when the sample is an aqueous solution, chemical interactions between the Al surface and sample, promoted by corrosive entities such as chloride ions and certain conditions of pH, can compromise the integrity of the cell and interfere with the experiment. In this study, the corrosion susceptibilities of Al and its alloys were investigated by subjecting them to various treatments; the results were compared with those of other candidate materials with low chemical reactivity. This work showed that alloys with higher Al content and boehmite-coated surfaces are resistant to corrosion. In particular, for Al, the resistance is due to a reduction in the contact area achieved by reducing the surface roughness. QENS measurements of empty sample cells made of these materials revealed two results: (1) the profile of the cell fabricated with a copper-free Al alloy showed a minor dependence on the scattering vector magnitude $$Q$$ and (2) reducing the real surface area of Al effectively suppresses its scattering intensity, while boehmite coating strengthens the scattering. Cells fabricated with Mo, Nb and single-crystal sapphire can be used as alternatives to Al because of their low scattering intensity and reduced dependence on $$Q$$.


Polarization analysis for small-angle neutron scattering with a $$^{3}$$He spin filter at a pulsed neutron source

奥平 琢也; 上田 祐生; 廣井 孝介; 元川 竜平; 稲村 泰弘; 高田 慎一; 奥 隆之; 鈴木 淳市*; 高橋 慎吾*; 遠藤 仁*; et al.

Journal of Applied Crystallography, 54(2), p.548 - 556, 2021/04

 被引用回数:0 パーセンタイル:0.01(Chemistry, Multidisciplinary)



Development of spin-contrast-variation neutron powder diffractometry for extracting the structure factor of hydrogen atoms

三浦 大輔*; 熊田 高之; 関根 由莉奈; 元川 竜平; 中川 洋; 大場 洋次郎; 大原 高志; 高田 慎一; 廣井 孝介; 森川 利明*; et al.

Journal of Applied Crystallography, 54(2), p.454 - 460, 2021/04

 被引用回数:1 パーセンタイル:28.41(Chemistry, Multidisciplinary)



In-house texture measurement using a compact neutron source

徐 平光; 池田 義雅*; 箱山 智之*; 高村 正人*; 大竹 淑恵*; 鈴木 裕士

Journal of Applied Crystallography, 53(2), p.444 - 454, 2020/04


 被引用回数:6 パーセンタイル:70.21(Chemistry, Multidisciplinary)

In order to improve the instrumental accessibility of neutron diffraction technique, the emerging compact neutron sources and in-house neutron diffractometers as a good complementary way have caused wide attention while their analysis precision seems problematic for the practical application. As a challenging project, the RIKEN accelerator-driven compact neutron source (RANS) was employed to establish the technical environment for texture measurement, and the recalculated pole figures and the orientation distribution function (ODF) of an interstitial-free (IF) steel sheet obtained from RANS were compared with the results from another two neutron diffractometers well-established for texture measurement. Moreover, the parameter "square integration of ODF difference" originally for evaluating the numerical error between the measured and simulated textures was generalized here to examine the reliability of RANS texture measurement. These quantitative comparisons revealed that the precise neutron diffraction texture measurement at RANS has been realized successfully and the following technical optimizations are much valuable, including the thickness selection of polyethylene moderator, the sample-to-detector distance, the B$$_{4}$$C shielding sheets for the reduced background noise, and the fine region division of the neutron detector panel. Moreover, the Rietveld texture analysis improves the texture reliability through avoiding the unfavorable influence of the uncertain diffraction intensity involved in the low counting, long wavelength incident neutrons at large scattering angles. Above technical results may accelerate the development of other easily accessible engineering materials evaluation techniques using compact neutron source, and also help to improve the data-collecting efficiency for various time-sliced scattering experiments at large neutron facilities.


Development of spin-contrast-variation neutron reflectometry for the structural analysis of multilayer films

熊田 高之; 阿久津 和宏*; 大石 一城*; 森川 利明*; 河村 幸彦*; 佐原 雅恵*; 鈴木 淳市*; 鳥飼 直也*

Journal of Applied Crystallography, 52(5), p.1054 - 1060, 2019/10


 被引用回数:2 パーセンタイル:26.77(Chemistry, Multidisciplinary)



Quasielastic neutron scattering of brucite to analyse hydrogen transport on the atomic scale

奥地 拓生*; 富岡 尚敬*; Purevjav, N.*; 柴田 薫

Journal of Applied Crystallography, 51, p.1564 - 1570, 2018/12


 被引用回数:1 パーセンタイル:12.44(Chemistry, Multidisciplinary)

中性子準弾性散乱(QENS)は、鉱物結晶格子内で起こる原子スケール水素拡散プロセスを分析するための新規かつ有効な方法であることが実証されている。この方法は、凝縮体中の拡散性が高い水素原子または水分子の拡散頻度および距離を分析するために敏感であると以前から考えられていた。本論文では、水酸基として結晶格子に結合している非常に遅い運動の水素原子の拡散運動を分析する応用研究の結果が示されている。ブルーサイト鉱物( brucite)、Mg(OH)$$_{2}$$では、水素原子の単一の二次元層面内でのジャンプとそれに最も近い次の層へのジャンプの2種類の水素拡散プロセスが観察された。ブルーサイトの結晶構造内で観察されるこれらの拡散プロセスは、層状構造を有する様々な種類の酸化物およびミネラル内で起こる水素拡散現象にQENS測定が適用可能であることを示している。


Stroboscopic time-of-flight neutron diffraction during cyclic testing using the event data recording system at J-PARC

川崎 卓郎; 稲村 泰弘; 伊藤 崇芳*; 中谷 健; Harjo, S.; Gong, W.*; 相澤 一也

Journal of Applied Crystallography, 51(3), p.630 - 634, 2018/06

 被引用回数:3 パーセンタイル:33.22(Chemistry, Multidisciplinary)

A time-resolved time-of-flight neutron diffraction technique to characterize the structural properties of materials during cyclic tests has been developed. By adopting the developed technique, the behaviors of the crystal lattice and domains of the piezoelectric material in a multilayer-type piezoelectric actuator driven by a cyclic electric field were evaluated. The variation in diffraction intensity during the application of a cyclic electric field was obtained successfully, and the hysteresis-like behaviors of both the lattice strain and the 90$$^{circ}$$ domain switching were revealed.


High stereographic resolution texture and residual stress evaluation using time-of-flight neutron diffraction

徐 平光; Harjo, S.; 小島 真由美*; 鈴木 裕士; 伊藤 崇芳*; Gong, W.; Vogel, S. C.*; 井上 純哉*; 友田 陽*; 相澤 一也; et al.

Journal of Applied Crystallography, 51(3), p.746 - 760, 2018/06


 被引用回数:22 パーセンタイル:90.22(Chemistry, Multidisciplinary)

Neutron diffraction texture measurements provide bulk textures with excellent grain statistics even for large grained materials, together with the crystallographic parameters and microstructure information such as phase fractions, coherent crystallite size, root mean square microstrain, macroscopic/intergranular stress/strain. The procedure for high stereographic resolution texture and residual stress evaluation was established at the TAKUMI engineering materials diffractometer. The pole figure evaluation of a limestone standard sample with a trigonal crystal structure suggested that the obtained precision for texture measurement is comparable with the oversea well-established neutron beam lines utilized for texture measurements. A high strength martensite-austenite multilayered steel was employed for further verification of the reliability of simultaneous Rietveld analysis of multiphase textures and macro stress tensors. By using a geometric mean micro-mechanical model, the macro stress tensor analysis with a plane stress assumption showed a RD-TD in-plane compressive stress (about -330 MPa) in martensite layers and a RD-TD in-plane tensile stress (about 320 MPa) in austenite layers. The phase stress partitioning was ascribed to the additive effect of volume expansion during martensite transformation and the linear contraction misfit during water quenching.


Inverse pole figure mapping of bulk crystalline grains in a polycrystalline steel plate by pulsed neutron Bragg-dip transmission imaging

佐藤 博隆*; 塩田 佳徳*; 諸岡 聡; 戸高 義一*; 足立 望*; 定松 直*; 及川 健一; 原田 正英; Zhang, S.*; Su, Y.; et al.

Journal of Applied Crystallography, 50(6), p.1601 - 1610, 2017/12

 被引用回数:12 パーセンタイル:73.91(Chemistry, Multidisciplinary)

A new mapping procedure for polycrystals using neutron Bragg-dip transmission is presented. This is expected to be useful as a new materials characterization tool which can simultaneously map the crystallographic direction of grains parallel to the incident beam. The method potentially has a higher spatial resolution than neutron diffraction imaging. As a demonstration, a Bragg-dip neutron transmission experiment was conducted at J-PARC on beamline MLF BL10 NOBORU. A large-grained Si-steel plate was used. Since this specimen included multiple grains along the neutron beam transmission path, it was a challenging task for existing methods to analyze the direction of the crystal lattice of each grain. A new data-analysis method for Bragg-dip transmission measurements was developed based on database matching. As a result, the number of grains and their crystallographic direction along the neutron transmission path have been determined.


Energy-resolved small-angle neutron scattering from steel

大場 洋次郎*; 諸岡 聡; 大石 一城*; 鈴木 淳市*; 高田 慎一; 佐藤 信浩*; 井上 倫太郎*; 土山 聡宏*; Gilbert, E. P.*; 杉山 正明*

Journal of Applied Crystallography, 50(2), p.334 - 339, 2017/04

 被引用回数:3 パーセンタイル:31.77(Chemistry, Multidisciplinary)

Recent progress of pulsed neutron sources has enabled energy-resolved analysis of neutron attenuation spectra, which include information on neutron scattering. In this study, a new analysis technique for small-angle neutron scattering (SANS) is demonstrated. A clear difference is observed in the neutron attenuation spectra between steels with different nanostructures; this difference can be understood as arising from attenuation due to SANS. The neutron attenuation spectra, calculated from the corresponding SANS profiles, agree well with the experimentally observed attenuation spectra. This result indicates that measurement of neutron attenuation spectra may enable the development of a novel experimental technique, i.e. energy-resolved SANS (ESANS).


Contrast variation by dynamic nuclear polarization and time-of-flight small-angle neutron scattering, 1; Application to industrial multi-component nanocomposites

能田 洋平*; 小泉 智*; 増井 友美*; 間下 亮*; 岸本 浩通*; 山口 大輔; 熊田 高之; 高田 慎一; 大石 一城*; 鈴木 淳市*

Journal of Applied Crystallography, 49(6), p.2036 - 2045, 2016/12

 被引用回数:16 パーセンタイル:76.39(Chemistry, Multidisciplinary)

We have reported the first attempt with dynamic nuclear polarization (DNP) and contrast variation small-angle neutron scattering (SANS) experiments on model mixtures for industrial tyres conducted at the MLF of J-PARC. We performed time-of-flight SANS (TOF-SANS) experiments, employing neutrons with a wide range, which causes imperfect neutron polarization and variations in the coherent and incoherent scattering lengths. By carefully eliminating the effect of imperfect neutron polarization, separation of the partial scattering functions was successfully demonstrated for the ternary system styrene-butadiene-rubber/silica/carbon.


Rapid measurement scheme for texture in cubic metallic materials using time-of-flight neutron diffraction at iMATERIA

小貫 祐介*; 星川 晃範*; 佐藤 成男*; 徐 平光; 石垣 徹*; 齋藤 洋一*; 轟 秀和*; 林 眞琴*

Journal of Applied Crystallography, 49(5), p.1579 - 1584, 2016/10


 被引用回数:25 パーセンタイル:88.04(Chemistry, Multidisciplinary)

The authors have developed texture measurement system on a time-of flight neutron diffractometer, iMATERIA (BL20, MLF/J-PARC, Japan). Quantitative Rietveld texture analysis for a duplex stainless steel was possible with one neutron beam exposure for several minutes without sample rotation. The minimum number of diffraction spectra required for the Rietveld texture analysis was experimentally determined as $$sim$$100. The suggested rapid measurement scheme used 132 spectra and determined volume fractions of texture components in both ferrite and austenite phases, quantitatively. This quantitative and rapid measurement scheme was established by utilizing the features of iMATERIA as a powder diffractometer, i.e. fairly high resolution in d-spacing and numerous detectors equipped in a wide range of scattering angle.


Magnetic scattering in the simultaneous measurement of small-angle neutron scattering and Bragg edge transmission from steel

大場 洋次郎*; 諸岡 聡; 大石 一城*; 佐藤 信浩*; 井上 倫太郎*; 足立 望*; 鈴木 淳市*; 土山 聡宏*; Gilbert, E. P.*; 杉山 正明*

Journal of Applied Crystallography, 49(5), p.1659 - 1664, 2016/10

 被引用回数:12 パーセンタイル:67.3(Chemistry, Multidisciplinary)

Pulsed neutron sources enable the simultaneous measurement of small-angle neutron scattering (SANS) and Bragg edge transmission. This simultaneous measurement is useful for microstructural characterization in steel. Since most steels are ferromagnetic, magnetic scattering contributions should be considered in both SANS and Bragg edge transmission analyses. An expression for the magnetic scattering contribution to Bragg edge transmission analysis has been derived. The analysis using this expression was applied to Cu steel. The ferrite crystallite size estimated from this Bragg edge transmission analysis with the magnetic scattering contribution was larger than that estimated using conventional expressions. This result indicates that magnetic scattering has to be taken into account for quantitative Bragg edge transmission analysis. In the SANS analysis, the ratio of magnetic to nuclear scattering contributions revealed that the precipitates consist of body-centered cubic Cu$$_{0.7}$$Fe$$_{0.3}$$ and pure Cu, which probably has 9R structure including elastic strain and vacancies. These results show that effective use of the magnetic scattering contribution allows detailed analyses of steel microstructure.


Investigation of dissimilar metal welds by energy-resolved neutron imaging

Tremsin, A. S.*; Ganguly, S.*; Meco, S. M.*; Pardal, G.*; 篠原 武尚; Bruce Feller, W.*

Journal of Applied Crystallography, 49(4), p.1130 - 1140, 2016/08


 被引用回数:16 パーセンタイル:76.39(Chemistry, Multidisciplinary)

A nondestructive study of the internal structure and compositional gradient of dissimilar metal-alloy welds through energy-resolved neutron imaging is described in this paper. The presence of Bragg edges in the measured neutron transmission spectra can be used to characterize the internal residual strain within the samples and some microstructural features, while neutron resonance absorption provides the possibility to map the degree of uniformity in mixing of the participating alloys and intermetallic formation within the welds. This paper demonstrates the potential of neutron energy-resolved imaging to measure all these characteristics simultaneously in a single experiment with sub-mm spatial resolution.


SENJU; A New time-of-flight single-crystal neutron diffractometer at J-PARC

大原 高志; 鬼柳 亮嗣; 及川 健一; 金子 耕士; 川崎 卓郎; 田村 格良; 中尾 朗子*; 花島 隆泰*; 宗像 孝司*; 茂吉 武人*; et al.

Journal of Applied Crystallography, 49(1), p.120 - 127, 2016/02

 被引用回数:44 パーセンタイル:95.79(Chemistry, Multidisciplinary)

SENJU, a time-of-flight Laue-type single-crystal neutron diffractometer, was developed at the Materials and Life Science Experimental Facility (MLF) of the Japan Accelerator Research Complex (J-PARC). Molecular structure analysis of a sub-millimeter taurine crystal and magnetic structure analysis of a MnF$$_{2}$$ crystal were performed to evaluate its performance.


High-speed three-dimensional reciprocal-space mapping during molecular beam epitaxy growth of InGaAs

Hu, W.; 鈴木 秀俊*; 佐々木 拓生*; 神津 美和*; 高橋 正光

Journal of Applied Crystallography, 45(5), p.1046 - 1053, 2012/10

 被引用回数:12 パーセンタイル:72.99(Chemistry, Multidisciplinary)

This paper describes the development of a high-speed three-dimensional reciprocal-space mapping method designed for the real-time monitoring of the strain relaxation process during the growth of heterostructure semiconductors. Each three-dimensional map is obtained by combining a set of consecutive images, which are captured during the continuous rotation of the sample, and calculating the reciprocal-space coordinates from the detector coordinate system. Using this method, the strain relaxation process of InGaAs heteroepitaxial films grown on GaAs(001) has been investigated.

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