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Journal Articles

Fluorous and organic extraction systems; A Comparison from the perspectives of coordination structures, interfaces, and bulk extraction phases

Ueda, Yuki; Micheau, C.; Akutsu, Kazuhiro*; Tokunaga, Kohei; Yamada, Masako*; Yamada, Norifumi*; Bourgeois, D.*; Motokawa, Ryuhei

Langmuir, 40(46), p.24257 - 24271, 2024/11

Microscopic structures in liquid-liquid extraction, such as structuration between extractants or extracted complexes in bulk organic phases and at interfaces, can influence macroscopic phenomena, such as the distribution behavior of solutes, including extraction efficiency, selectivity, and phase separation of the organic phase. In this study, we correlated the macroscopic behavior of the extraction of Zr(IV) ions from nitric acid solutions with microscopic structural information in order to understand at the molecular level the key factors contributing to the higher metal ion extraction performance in the fluorous extraction system comprising fluorous phosphate (TFP) in perfluorohexane as compared to the analogous organic extraction system comprising organic phosphate (THP) in n-hexane. Extended X-ray absorption fine structure, neutron reflectometry, and small-angle neutron scattering revealed the local coordination structure around the Zr(IV) ion, the accumulation of extractant molecules at the interface, and the structuration of extractant molecules in the bulk extraction phase, respectively. In the fluorous extraction system, extractant aggregates with were formed after contact with nitric acid. In contrast, in the organic extraction system, only extractant dimers were formed. We speculate that differences in the local coordination structure around the Zr(IV) ion and the structuration of the extractant molecules in the bulk extraction phase contribute to the high Zr(IV) extraction performance in the fluorous extraction system. In particular, the size of the aggregates hardly changed with increasing Zr(IV) concentration in the fluorous phase, which may be closely related to the absence of phase splitting in the fluorous extraction system.

Journal Articles

None

Ueda, Yuki; Micheau, C.; Motokawa, Ryuhei

Shiki, 64, p.2 - 6, 2024/09

no abstracts in English

Journal Articles

Globular pattern formation of hierarchical ceria nanoarchitectures

Aoyagi, Noboru; Motokawa, Ryuhei; Okumura, Masahiko; Ueda, Yuki; Saito, Takumi*; Nishitsuji, Shotaro*; Taguchi, Tomitsugu*; Yomogida, Takumi; Sazaki, Gen*; Ikeda, Atsushi

Communications Chemistry (Internet), 7, p.128_1 - 128_13, 2024/06

 Times Cited Count:0 Percentile:0.00(Chemistry, Multidisciplinary)

Journal Articles

Low-background ultrahigh-purity aluminium window for small-angle neutron scattering using monochromatic cold neutrons

Kumada, Takayuki; Motokawa, Ryuhei; Iwase, Hiroki*

Journal of Applied Crystallography, 57(Part 3), p.728 - 733, 2024/06

 Times Cited Count:0 Percentile:0.00(Chemistry, Multidisciplinary)

Journal Articles

Impact of branching position and degree on uranium extraction by amines; A Supramolecular and thermodynamic study

Guerinoni, E.*; Giusti, F.*; Dourdain, S.*; Dufr$^e$che, J.-F.*; Motokawa, Ryuhei; Ueda, Yuki; Aoyagi, Noboru; Zemb, T.*; Pellet-Rostaing, S.*

Journal of Molecular Liquids, 403, p.124820_1 - 124820_11, 2024/06

 Times Cited Count:0 Percentile:0.00(Chemistry, Physical)

Journal Articles

Analyses of hierarchical structures in SBR rubber by using contrast-variation SANS; Effects of a silane coupling agent

Nakanishi, Yohei*; Shibata, Motoki*; Sawada, Satoshi*; Kondo, Hiroaki*; Motokawa, Ryuhei; Kumada, Takayuki; Yamamoto, Katsuhiro*; Mita, Kazuki*; Miyazaki, Tsukasa*; Takenaka, Mikihito*

Polymer, 306, p.127209_1 - 127209_7, 2024/06

 Times Cited Count:1 Percentile:0.00(Polymer Science)

Journal Articles

Nanometer-thick crystalline ice plates in rapidly-frozen glucose solution observed by spin-contrast-variation small-angle neutron scattering

Kumada, Takayuki; Nakagawa, Hiroshi; Miura, Daisuke; Sekine, Yurina; Motokawa, Ryuhei; Hiroi, Kosuke; Inamura, Yasuhiro; Oku, Takayuki; Oishi, Kazuki*; Morikawa, Toshiaki*; et al.

Hamon, 34(2), p.50 - 53, 2024/05

Spin-contrast-variation (SCV) small-angle neutron scattering (SANS) enabled us to determine structure of nano-ice crystals that were generated in rapidly frozen sugar solution. In the frozen glucose solution, we found that the nano-ice crystals formed a planar structure with a radius larger than several tens of nanometers and a thickness of 2-3 nm, which was close to the critical nucleation size of ice crystals in supercooled water. This result suggests that the glucose molecules were preferentially bound to a specific face of nano-ice crystals, and then blocked the crystal growth perpendicular to that face.

Journal Articles

Organization of malonamides from the interface to the organic bulk phase

Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Akutsu, Kazuhiro*; Yamada, Norifumi*; Yamada, Masako*; Moussaoui, S. A.*; Makombe, E.*; Meyer, D.*; Berthon, L.*; et al.

Journal of Molecular Liquids, 401, p.124372_1 - 124372_12, 2024/05

 Times Cited Count:0 Percentile:0.00(Chemistry, Physical)

Journal Articles

Interpenetration of rubber and silane coupling agent on an inorganic substrate revealed by spin-contrast-variation neutron reflectivity

Kumada, Takayuki; Iwahara, Daisuke*; Nishitsuji, Shotaro*; Akutsu, Kazuhiro*; Miura, Daisuke; Motokawa, Ryuhei; Sugita, Tsuyoshi; Torikai, Naoya*; Amino, Naoya*; Oku, Takayuki; et al.

Journal of Physical Chemistry C, 128(21), p.8797 - 8802, 2024/05

 Times Cited Count:0 Percentile:0.00(Chemistry, Physical)

We elucidated the entanglement of polybutadiene and silane coupling agent (SCA) molecules bound to Si substrates using spin-contrast-variation (SCV) neutron reflectivity (NR). In an annealed integral blend film of polybutadiene and SCA, a SCA layer generated on the Si substrate was composed of 70 vol. percent SCA molecules extended perpendicularly from the silicon substrate and entangled with 30 vol. percent polybutadiene molecules. By contrast, in an SCA-precoated polybutadiene film, the SCA-precoated layer is composed of densely packed SCA molecules forming crystal-like structure, and thus did not become entangled with the postcoated polybutadiene molecules. This poor entanglement resulted in poor binding between polybutadiene and Si substrate.

Journal Articles

Freeze-crosslinking approach for preparing carboxymethyl cellulose nanofiber/zirconium hydrogels as fluoride adsorbents

Sekine, Yurina; Nankawa, Takuya; Sugita, Tsuyoshi; Nagakawa, Yoshiyasu*; Shibayama, Yuki; Motokawa, Ryuhei; Ikeda-Fukazawa, Tomoko*

Nanoscale, 16(19), p.9400 - 9405, 2024/05

 Times Cited Count:1 Percentile:70.85(Chemistry, Multidisciplinary)

A tough carboxymethyl cellulose nanofiber (CMF)/ zirconium (Zr) hydrogel was obtained by freeze cross-linking method. The hydrogel was prepared by adding HCl solution containing Zr to frozen CMF and thawing it. The hydrogel showed high adsorptivity for fluoride. This simple gelation method provides useful insight for developing hydrogel-metal complexes.

Journal Articles

Synthesis of heat-resistant living polymer particles by one-step reversible addition-fragmentation chain transfer precipitation polymerization of styrene and $$N$$-phenylmaleimide

Yamazaki, Shun*; Kaneko, Naoya*; Kato, Atsuya*; Watanabe, Kohei*; Aoki, Daisuke*; Taniguchi, Tatsuo*; Karatsu, Takashi*; Ueda, Yuki; Motokawa, Ryuhei; Okura, Koki*; et al.

Polymer, 298, p.126846_1 - 126846_11, 2024/04

 Times Cited Count:0 Percentile:0.00(Polymer Science)

Journal Articles

Contrast dependence of scattering profiles for poly(ethylene glycol) in water; Investigation by small-angle neutron scattering with $$^{3}$$He spin filter and small-angle X-ray scattering

Ryoki, Akiyuki*; Watanabe, Fumi*; Okudaira, Takuya*; Takahashi, Shingo*; Oku, Takayuki; Hiroi, Kosuke; Motokawa, Ryuhei; Nakamura, Yo*

Journal of Chemical Physics, 160(11), p.114907_1 - 114907_9, 2024/03

 Times Cited Count:0 Percentile:0.00(Chemistry, Physical)

Journal Articles

Upgrade of the small-angle neutron scattering diffractometer SANS-J at JRR-3

Kumada, Takayuki; Motokawa, Ryuhei; Oba, Yojiro; Nakagawa, Hiroshi; Sekine, Yurina; Micheau, C.; Ueda, Yuki; Sugita, Tsuyoshi; Birumachi, Atsushi; Sasaki, Miki; et al.

Journal of Applied Crystallography, 56(6), p.1776 - 1783, 2023/12

 Times Cited Count:10 Percentile:97.31(Chemistry, Multidisciplinary)

The combination of the existing position-sensitive photomultiplier and the $$^{3}$$He main detector with focusing devices, and the newly installed front detectors in SANS-J at JRR-3 covers small-angle neutron scattering signals in the range of the magnitude of the scattering vector Q from 0.002 to 6 nm-1 gaplessly with three standard device layouts. The installation of the front detector and a graphical user interface system largely improved the usability of SANS-J.

Journal Articles

Water fraction dependence of the aggregation behavior of hydrophobic fluorescent solutes in water-tetrahydrofuran

Tsuji, Hayato*; Nakahata, Masaki*; Hishida, Mafumi*; Seto, Hideki*; Motokawa, Ryuhei; Inoue, Takeru*; Egawa, Yasunobu*

Journal of Physical Chemistry Letters (Internet), 14(49), p.11235 - 11241, 2023/12

 Times Cited Count:3 Percentile:61.71(Chemistry, Physical)

Journal Articles

Structural changes of polystyrene particles in subcritical and supercritical water revealed by in situ small-angle neutron scattering

Shibata, Motoki*; Nakanishi, Yohei*; Abe, Jun*; Arima, Hiroshi*; Iwase, Hiroki*; Shibayama, Mitsuhiro*; Motokawa, Ryuhei; Kumada, Takayuki; Takata, Shinichi; Yamamoto, Katsuhiro*; et al.

Polymer Journal, 55(11), p.1165 - 1170, 2023/11

 Times Cited Count:2 Percentile:35.88(Polymer Science)

Journal Articles

Polarized neutrons observed nanometer-thick crystalline ice plates in frozen glucose solution

Kumada, Takayuki; Nakagawa, Hiroshi; Miura, Daisuke; Sekine, Yurina; Motokawa, Ryuhei; Hiroi, Kosuke; Inamura, Yasuhiro; Oku, Takayuki; Oishi, Kazuki*; Morikawa, Toshiaki*; et al.

Journal of Physical Chemistry Letters (Internet), 14(34), p.7638 - 7643, 2023/08

 Times Cited Count:0 Percentile:0.00(Chemistry, Physical)

The structure of nano-ice crystals in rapidly frozen glucose solution was elucidated by using spin-contrast-variation small-angle neutron scattering, which distinguishes the nano-ice crystal signal from the frozen amorphous solution signal by the polarization-dependent neutron scattering. The analysis revealed that the nano-ice crystals form a planar structure with a diameter exceeding tens of nanometers and a thickness of 1 nm, which is close to the critical nucleation size. This result suggests that the glucose molecules are preferentially bound to a specific face of nano-ice crystals, and then block the crystal growth perpendicular to that face.

Journal Articles

Heterogeneous aggregation of humic acids studied by small-angle neutron and X-ray scattering

Saito, Takumi*; Motokawa, Ryuhei; Okubo, Takahiro*; Miura, Daisuke*; Kumada, Takayuki

Environmental Science & Technology, 57(26), p.9802 - 9810, 2023/07

 Times Cited Count:1 Percentile:20.32(Engineering, Environmental)

Journal Articles

Foam flotation of clay particles using a bifunctional amine surfactant

Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Bauduin, P.*; Girard, L.*; Diat, O.*

Langmuir, 39(31), p.10965 - 10977, 2023/07

 Times Cited Count:7 Percentile:75.15(Chemistry, Multidisciplinary)

Journal Articles

Neutron resonance absorption imaging of simulated high-level radioactive waste in borosilicate glass

Oba, Yojiro; Motokawa, Ryuhei; Kaneko, Koji; Nagai, Takayuki; Tsuchikawa, Yusuke; Shinohara, Takenao; Parker, J. D.*; Okamoto, Yoshihiro

Scientific Reports (Internet), 13, p.10071_1 - 10071_8, 2023/06

 Times Cited Count:2 Percentile:65.72(Multidisciplinary Sciences)

Journal Articles

Hierarchical aggregation in a complex fluid; The Role of isomeric interconversion

Massey, D.*; Williams, C. D.*; Mu, J.*; Masters, A. J.*; Motokawa, Ryuhei; Aoyagi, Noboru; Ueda, Yuki; Antonio, M. R.*

Journal of Physical Chemistry B, 127(9), p.2052 - 2065, 2023/03

 Times Cited Count:1 Percentile:0.00(Chemistry, Physical)

160 (Records 1-20 displayed on this page)