Proton chelating ligands drive improved chemical separations for rhodium

Narita, Hirokazu*; Nicolson, R. M.*; Motokawa, Ryuhei; Ito, Fumiyuki*; Morisaku, Kazuko*; Goto, Midori*; Tanaka, Mikiya*; Heller, W. T.*; Shiwaku, Hideaki; Yaita, Tsuyoshi; et al.

Inorganic Chemistry, 58(13), p.8720 - 8734, 2019/07

https://doi.org/10.1021/acs.inorgchem.9b01136

Phase-transition kinetics of magnetic skyrmions investigated by stroboscopic small-angle neutron scattering

Nakajima, Taro*; Inamura, Yasuhiro; Ito, Takayoshi*; Oishi, Kazuki*; Oike, Hiroshi*; Kagawa, Fumitaka*; Kikkawa, Akiko*; Taguchi, Yasujiro*; Kakurai, Kazuhisa*; Tokura, Yoshinori*; et al.

Physical Review B, 98(1), p.014424_1 - 014424_5, 2018/07

https://doi.org/10.1103/PhysRevB.98.014424

We investigated the phase-transition kinetics of magnetic skyrmion lattice (SkL) in MnSi by means of stroboscopic small-angle neutron scattering (SANS). Temporal evolutions of SANS patterns were measured with time resolution of 13 ms while sweeping temperature as fast as 50 Ks. It turned out that the paramagnetic-to-SkL transition immediately occurs upon traversing the equilibrium phase boundary on the rapid cooling, whereas the SkL-to-conical transition can be kinetically avoided to realize the low-temperature metastable SkL with a long-range magnetic order. The formation of the metastable SkL was found to be strongly dependent not only on cooling rate, but also on magnetic eld and trajectory in the H-T phase diagram.

Recent research in solvent extraction of platinum group metals

Narita, Hirokazu*; Suzuki, Tomoya*; Motokawa, Ryuhei

Nippon Kinzoku Gakkai-Shi, 81(4), p.157 - 167, 2017/04

https://doi.org/10.2320/jinstmet.JE201604

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.

Photonic crystals fabricated by block copolymerization-induced microphase separation

Motokawa, Ryuhei; Taniguchi, Tatsuo*; Kumada, Takayuki; Iida, You*; Aoyagi, Shota*; Sasaki, Yusuke*; Kori, Michinari*; Kishikawa, Keiki*

Macromolecules, 49(16), p.6041 - 6049, 2016/08

https://doi.org/10.1021/acs.macromol.6b01190

Small-angle neutron scattering

Suzuki, Junichi

Nippon Kessho Gakkai-Shi, 46(6), p.381 - 389, 2004/12

https://doi.org/10.5940/jcrsj.46.381

no abstracts in English

Feasibility study on application of a magnetic neutron lens to SANS experiments

Oku, Takayuki; Suzuki, Junichi; Sasao, Hajime*; Adachi, Tomohiro*; Shinohara, Takenao*; Ikeda, Kazuaki*; Morishima, Takahiro*; Sakai, Kenji*; Kiyanagi, Yoshiaki*; Furusaka, Michihiro*; et al.

Nuclear Instruments and Methods in Physics Research A, 529(1-3), p.116 - 119, 2004/08

https://doi.org/10.1016/j.nima.2004.04.190

As a neutron has a magnetic dipole moment, it is accelerated in a magnetic field gradient. Thus, we can control a neutron trajectory free from neutron beam attenuation and scattering using the magnetic field gradient. A sextupole magnetic field functions as a neutron focusing and defocusing lens depending on the neutron spin state. The neutron focusing effect was experimentally verified using a 6-piece permanent sextupole magnet. For the application in practical neutron scattering experiments, a sextupole magnet with a sufficiently large aperture accompanied with strong focusing power is demanded. Recently, a superconducting sextupole magnet, a Halbach-type permanent sextupole magnet and a sextupole pulse electro-magnet have been developed in a project of the development and application of neutron optics. These magnets will be dedicated to practical uses in neutron scattering experiments. In this paper, current status of the development of the magnetic neutron lenses is reported, and their application in the neutron scattering experiments is discussed.

An Insight into the pathway of the amyloid fibril formation of hen egg white lysozyme obtained from a small-angle X-ray and neutron scattering study

Yonezawa, Yasushige*; Tanaka, Shimpei*; Kubota, Tomomi*; Wakabayashi, Katsuzo*; Yutani, Katsuhide*; Fujiwara, Satoru

Journal of Molecular Biology, 323(2), p.237 - 251, 2002/10

https://doi.org/10.1016/S0022-2836(02)00941-5

It is known that hen egg white lysozyme (HEWL) forms amyloid fibrils in highly concentrated ethanol solutions. In order to gain an insight into the mechanism of the amyloid fibril formation, the structures of HEWL in solutions of various protein and ethanol concentrations were investigated with small-angle X-ray and neutron scattering. It was shown that the structural states of HEWL were distinguished as the monomer state, the state of the dimer formation, the state of the protofilament formation, the protofilament state, and the state towards the formation of the amyloid fibrils. Circular dichroism measurements showed that the large changes in the secondary structures of HEWL occurred during the dimer formation. Structural characterization showed that the dimers had an elongated shape, the protofilaments were formed by stacking of the dimers with their long axis (nearly) perpendicular to the protofilament axis, and the changes of the structural states towards the amyloid fibril formation occurred via lateral association of the protofilaments.

Small angle neutron scattering study on PrCaMnO; Evidence of two-phase coexistence

Yamada, Yasusada*; Iwase, Takeshi*; Wakahiki, Masaya*; Suzuki, Junichi

Journal of the Physical Society of Japan, 70(6), p.1593 - 1597, 2001/06

https://doi.org/10.1143/JPSJ.70.1593

no abstracts in English

Frozen concentration fluctuations of a poly(N-isopropyl acrylamide) gel decomposed by neutron spin echo

Koizumi, Satoshi; Monkenbusch, M.*; Richter, D.*; Schwahn, D.*; Annaka, Masahiko*

Journal of the Physical Society of Japan, Vol.70, Supplement A, p.320 - 322, 2001/05

no abstracts in English