Polarization analysis for small-angle neutron scattering with a He spin filter at a pulsed neutron source

Okudaira, Takuya; Ueda, Yuki; Hiroi, Kosuke; Motokawa, Ryuhei; Inamura, Yasuhiro; Takata, Shinichi; Oku, Takayuki; Suzuki, Junichi*; Takahashi, Shingo*; Endo, Hitoshi*; et al.

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

https://doi.org/10.1107/S1600576721001643

Neutron polarization analysis (NPA) for small-angle neutron scattering (SANS) experiments using a pulsed neutron source was successfully achieved by applying a He spin filter as a spin analyzer for the scattered neutrons. The He spin filter covers a sufficient solid angle for performing SANS experiments, and the relaxation time of the He polarization is sufficient for continuous use over a few days, thus reaching the typical duration required for a complete set of SANS experiments. Although accurate evaluation of the incoherent neutron scattering, which is predominantly attributable to hydrogen atoms in samples, is practically difficult using calculations based on the sample elemental composition, the developed NPA approach with consideration of the influence of multiple neutron scattering enabled reliable decomposition of the SANS intensity distribution into the coherent and incoherent scattering components. To date, NPA has not been well established as a standard technique for SANS experiments at pulsed neutron sources. This work is anticipated to greatly contribute to the accurate determination of the coherent neutron scattering component for scatterers in various types of organic sample systems in SANS experiments at J-PARC.

Status of neutron spectrometers at J-PARC

Kajimoto, Ryoichi; Yokoo, Tetsuya*; Nakamura, Mitsutaka; Kawakita, Yukinobu; Matsuura, Masato*; Endo, Hitoshi*; Seto, Hideki*; Ito, Shinichi*; Nakajima, Kenji; Kawamura, Seiko

Physica B; Condensed Matter, 562, p.148 - 154, 2019/06

BB2018-0526.pdf:2.45MB

https://doi.org/10.1016/j.physb.2018.11.061

Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex, 2; Neutron scattering instruments

Nakajima, Kenji; Kawakita, Yukinobu; Ito, Shinichi*; Abe, Jun*; Aizawa, Kazuya; Aoki, Hiroyuki; Endo, Hitoshi*; Fujita, Masaki*; Funakoshi, Kenichi*; Gong, W.*; et al.

Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12

https://doi.org/10.3390/qubs1030009

The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC), is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.

Nanoscopic structural investigation of physically cross-linked nanogels formed from self-associating polymers

Sekine, Yurina; Endo, Hitoshi*; Iwase, Hiroki*; Takeda, Shigeo*; Mukai, Sadaatsu*; Fukazawa, Hiroshi; Littrell, K. C.*; Sasaki, Yoshihiro*; Akiyoshi, Kazunari*

Journal of Physical Chemistry B, 120(46), p.11996 - 12002, 2016/11

https://doi.org/10.1021/acs.jpcb.6b06795

The detailed structure of a nanogel formed by self-association of cholesterol-bearing pullulans (CHP) was determined by contrast variation small-angle neutron scattering. The decomposition of scattering intensities into partial scattering functions of each CHP nanogel component, i.e., pullulan, cholesterol, and the cross-term between the pullulan and the cholesterol allows us to investigate the internal structure of the nanogel. The effective spherical radius of the skeleton formed by pullulan chains was found to be about 8.1 nm. In the CHP nanogel, there are about 19 cross-linking points where a cross-linking point is formed by aggregation of trimer cholesterol molecules with the spatially inhomogeneous distribution of the mass fractal dimension of 2.6. The average radius of the partial chains can also be determined to be 1.7 nm. As the result, the complex structure of the nanogels is coherently revealed at the nanoscopical level.

Neutron polarization analysis for biphasic solvent extraction systems

Motokawa, Ryuhei; Endo, Hitoshi*; Nagao, Michihiro*; Heller, W. T.*

Solvent Extraction and Ion Exchange, 34(5), p.399 - 406, 2016/07

https://doi.org/10.1080/07366299.2016.1201980

Collective structural changes in vermiculite clay suspensions induced by cesium ions

Motokawa, Ryuhei; Endo, Hitoshi*; Yokoyama, Shingo*; Nishitsuji, Shotaro*; Kobayashi, Toru; Suzuki, Shinichi; Yaita, Tsuyoshi

Scientific Reports (Internet), 4, p.6585_1 - 6585_6, 2014/10

https://doi.org/10.1038/srep06585

Small-angle neutron scattering for biology; Application of SANS to biological study

Endo, Hitoshi; Sugiyama, Masaaki*; Inoue, Rintaro*

Hamon, 22(3), p.258 - 267, 2012/08

https://doi.org/10.5611/hamon.22.3_258

In this text, the authors introduce two powerful techniques and one developing one for Small-Angle Neutron Scattering (SANS). The most fascinating feature of neutron as a scattering probe is its isotope effect in hydrogen. The first topic is concerning about recent progress on Contrast Variation Method: the author shows how to apply the contrast variation method to protein-mineral complex system and analyze the data. The second is concerning about deuteration-labeling: the author shows kinetics analysis in quaternary structure of homo-oligomeric protein with this technique. The final topic is concerning about the next generation analysis: an analysis method coupling SANS with neutron spin echo for dynamics of tertiary structure of protein.

Dynamics of soft matter studied by neutron spin echo technique

Endo, Hitoshi

Kobunshi, 60(4), p.193 - 194, 2011/04

http://ci.nii.ac.jp/naid/10027971876

Neutron spin echo (NSE) technique is a quite unique and advanced method to study soft matter dynamics. In this manuscript, NSE technique and its applications are briefly reviewed. Then, the Japanese NSE spectrometer iNSE is overviewed. At the end, the future prospects of NSE in Japan are described.

The Static structure of polyrotaxane in solution investigated by contrast variation small-angle neutron scattering

Endo, Hitoshi; Mayumi, Koichi*; Osaka, Noboru*; Ito, Kozo*; Shibayama, Mitsuhiro*

Polymer Journal, 43(2), p.155 - 163, 2011/02

https://doi.org/10.1038/pj.2010.124

Polyrotaxane (PR) possesses a supramolecular structure in which cyclic molecules are threaded into an axial polymer. In this study, the static structure of PR dissolved in a good solvent was investigated using contrast variation small-angle neutron scattering. The conformation of the axial linear polymer and the alignment of cyclic molecules within the axial polymer were evaluated quantitatively with the help of a detailed derivation of scattering theory. The decomposed partial scattering functions of the cyclic molecules and the axial polymer and the cross-correlation between cyclic molecules and an axial polymer strongly supported the idea that the alignment of cyclic molecules threaded on the axial polymer is random. On the basis of experimental observation, the entropic origin of the stiffening of PR due to the array of cyclic molecules is discussed.

SANS and EXAFS study of hierarchical structure assembled by coordination species in biphasic solvent extraction

Motokawa, Ryuhei; Kobayashi, Toru; Endo, Hitoshi*; Suzuki, Shinichi; Yaita, Tsuyoshi; Shiwaku, Hideaki

no journal, ,