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Journal Articles

Development of cation and anion exchange membranes for saline water concentration using high-energy heavy-ion beams

Sawada, Shinichi*; Yasukawa, Masahiro*; Koshikawa, Hiroshi*; Kitamura, Akane; Higa, Mitsuru*; Yamaki, Tetsuya*

Nippon Kaisui Gakkai-Shi, 73(4), p.208 - 216, 2019/08

For applications to saline water concentration by electrodialysis, we prepared nano-structure-controlled cation and anion exchange membranes (CEMs and AEMs) by a so-called ion-track grafting technique. This new technique involves irradiation of a polymer substrate with an MeV-GeV heavy-ion beam to form the nano-sized cylindrical ion tracks and the graft polymerization only into the ion tracks for the creation of one-dimensional transport pathways. A 25-$$mu$$m-thick poly(ethylene-co-tetrafluoroethylene) film was irradiated with 560 MeV $$^{129}$$Xe or 310 MeV $$^{84}$$Kr. The irradiated films were immersed in grafting solutions of ethyl p-styrenesulfonate (EtSS) and chloromethylstyrene (CMS),and then subjected to the hydrolysis of EtSS units and quaternization of CMS units to prepare CEMs and AEMs, respectively. These CEMs and AEMs showed lower resistance than the commercially-available membranes even at the very low water uptake. This would be due to the signifcantly-effcient transport of ions through the unique one-dimensional highly-connected transport pathways. In the saline water concentration experiment, a pair of our CEM and a commercial AEM or vice versa led to a higher salt concentration in the concentration chamber than did a pair of the commercial membranes. This result demonstrated great applicability of our ion-track-grafted CEMs and AEMs for saline water concentration.

Journal Articles

FE-SEM observations of multiple nanohillocks on SrTiO$$_{3}$$ irradiated with swift heavy ions

Kitamura, Akane; Ishikawa, Norito; Kondo, Keietsu; Fujimura, Yuki; Yamamoto, Shunya*; Yamaki, Tetsuya*

Transactions of the Materials Research Society of Japan, 44(3), p.85 - 88, 2019/06

Swift heavy ions can create nanosized hillocks on the surfaces of various ceramics. When these materials are irradiated with swift heavy ions at normal incidence, each ion impact results in the formation of a single hillock on the surfaces. In contrast, irradiation at grazing incidence forms chains of multiple hillocks on the surface, for example, for strontium titanate (SrTiO$$_{3}$$). So far, chains of multiple hillocks have been investigated using atomic force microscopy (AFM). It should be noted that AFM measurements involve systematic errors of several nanometers due to the finite size of the probe tip. Consequently, it is possible that the image of one hillock may merge with that of a neighboring hillock even if the two hillocks are well separated. In contrast to AFM, field-emission scanning electron microscopy (FE-SEM) is a useful technique for obtaining higher-resolution images. In this study, we observed multiple nanohillocks on the surfaces of SrTiO$$_{3}$$ using FE-SEM. Crystals of SrTiO$$_{3}$$(100) and 0.05 wt% Nb-doped SrTiO$$_{3}$$(100) were irradiated with 350 MeV Xe ions, respectively, at grazing incidence, where the angle between the sample surface and the beam was less than 2$$^{circ}$$. On the SrTiO$$_{3}$$ surface, a chain of periodic nanohillocks is created along the ion path. In contrast, black lines accompanied by hillocks are observed on the Nb-doped SrTiO$$_{3}$$ surface.

Journal Articles

Fluoropolymer-based nanostructured membranes created by swift-heavy-ion irradiation and their energy and environmental applications

Yamaki, Tetsuya*; Nuryanthi, N.*; Kitamura, Akane; Koshikawa, Hiroshi*; Sawada, Shinichi*; Voss, K.-O.*; Severin, D.*; Tautmann, C.*

Nuclear Instruments and Methods in Physics Research B, 435, p.162 - 168, 2018/11

 Percentile:100(Instruments & Instrumentation)

We used individual single-ion tracks in fluoropolymers with diameters of tens to hundreds of nanometers; chemical etching and ion-track grafting enabled us to develop ion-track and proton-conductive membranes, respectively. In the ion-track membranes of PVDF, strongly-LET-dependent etching was found, so the pore shape as well as the size was exclusively controlled by the track structures. We performed the ion-track grafting of styrene into ETFE to develop nanostructure-controlled proton exchange membranes (PEMs) for applications in PEM fuel cells. Our ion beam technology to develop fluoropolymer-based nanostructures has the potential to apply in the field of filtration processes and fuel cell devices. This would make it possible to provide new microfiltration technology for water treatment, sterilization, petroleum refining and dairy processing.

Journal Articles

Research on nanostructure-controlled functional membranes using high-energy ion beams; Fluoropolymer-based porous and ion-exchange membranes

Yamaki, Tetsuya*; Kitamura, Akane; Sawada, Shinichi*; Koshikawa, Hiroshi*

Nippon Kaisui Gakkai-Shi, 72(2), p.62 - 74, 2018/04

This review paper is devoted to two topics, i.e., fluoropolymer-based porous and ion-exchange membranes, both of which include the creation of nanostructure-controlled functional membranes with high-energy ion beams. Latent tracks of the MeV-GeV heavy ions in a polymer foil can sometimes be chemically etched out to form a membrane with micro- and nano-sized through-pores, the so-called ion-track membrane. Our focus is on ion-track membranes of poly (vinylidene fluoride) (PVDF) and cation- and anion-exchange membranes (CEMs and AEMs, respectively).

Journal Articles

Ion track etching of PVDF films irradiated with fast C$$_{60}$$$$^{+}$$ cluster ions

Kitamura, Akane; Yamaki, Tetsuya*; Chiba, Atsuya*; Usui, Aya

QST-M-8; QST Takasaki Annual Report 2016, P. 37, 2018/03

We investigated the track-etched surface of PVDF films irradiated with C$$_{60}$$$$^{+}$$ cluster ions, comparing the data with C$$^{+}$$ monoatomic ions. PVDF films were irradiated with 6 MeV C$$_{60}$$$$^{+}$$ cluster ions. The energy of the each carbon ion is 100 keV/atom; thus, for comparison, the PVDF films were also irradiated with 100 keV C$$^{+}$$ ions. SEM and AFM observation showed that the surface irradiated with C$$_{60}$$$$^{+}$$ cluster ions apparently possessed flat-bottomed pores with an average diameter and depth of approximately 400 and 250 nm, respectively. On the other hand, track-etched pores were also formed on the surface irradiated with C$$^{+}$$ ions, but their morphology was irregular or obscure. In the irradiation with the C$$_{60}$$$$^{+}$$ cluster ions, the surface diameter of track-etched pores increased with increasing the etching time. The tracks of the 100 keV C$$^{+}$$ ions seemed to be hardly developed by the etching when the time. In conclusion, the C$$_{60}$$$$^{+}$$ cluster ions irradiation caused a large size of etchable tracks on the PVDF surface. The result could represent the effect of local and simultaneous collision by the aggregated ions.

Journal Articles

Preparation of nano-structure controlled ion-exchange membranes by ion beams and their application to seawater concentration

Yamaki, Tetsuya*; Goto, Mitsuaki*; Sawada, Shinichi*; Koshikawa, Hiroshi*; Kitamura, Akane; Higa, Mitsuru*

QST-M-8; QST Takasaki Annual Report 2016, P. 35, 2018/03

We prepared ion exchange membranes by a heavy-ion-track grafting method, and then used them for seawater concentration process. Both the water uptake and resistance were lower for our ion-track grafted membranes than for the conventional $$gamma$$-ray-grafted membranes. The results would be because local and high-density energy deposition due to the ion beam enabled us to control the membrane structure in a nanometer scale. We demonstrate our membranes are suitable for this application.

Journal Articles

Microfabrication of fluoropolymers using ion beam irradiation

Kitamura, Akane; Kobayashi, Tomohiro*

Hoshasen Kagaku (Internet), (104), p.29 - 34, 2017/10

no abstracts in English

JAEA Reports

Light ion microbeam analysis / processing system and its improvement

Koka, Masashi; Ishii, Yasuyuki; Yamada, Naoto; Okubo, Takeru; Kada, Wataru*; Kitamura, Akane; Iwata, Yoshihiro*; Kamiya, Tomihiro; Sato, Takahiro

JAEA-Technology 2016-006, 41 Pages, 2016/03

JAEA-Technology-2016-006.pdf:14.03MB

A MeV-class light ion microbeam system has been developed for micro-analysis and micro-fabrication with high spatial resolution at 3-MV single-ended accelerator in Takasaki Ion Accelerators for Advanced Radiation Application of Takasaki Advanced Radiation Research Institute, Sector of Nuclear Science Research, Japan Atomic Energy Agency. This report describes the technical improvements for the main apparatus (the accelerator, beam-transport lines, and microbeam system), and auxiliary equipments/ parts for ion beam applications such as Particle Induced X-ray/Gamma-ray Emission (PIXE/PIGE) analysis, 3-D element distribution analysis using PIXE-Computed Tomography(CT), Ion Beam-Induced Luminescence (IBIL) analysis, and Proton Beam Writing with the microbeam scanning, with functional outline of these apparatus and equipments/parts.

Journal Articles

Particle induced X-ray emission-computed tomography analysis of an adsorbent for extraction chromatography

Sato, Takahiro; Yokoyama, Akihito; Kitamura, Akane; Okubo, Takeru; Ishii, Yasuyuki; Takahatake, Yoko; Watanabe, So; Koma, Yoshikazu; Kada, Wataru*

Nuclear Instruments and Methods in Physics Research B, 371, p.419 - 423, 2016/03

 Times Cited Count:2 Percentile:57.25(Instruments & Instrumentation)

Journal Articles

Current status of electrostatic accelerator at TIARA

Usui, Aya; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Kanai, Shinji*; Aoki, Yuki*; Hashizume, Masashi*; et al.

Dai-28-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.117 - 119, 2015/12

no abstracts in English

Journal Articles

Ion-track grafting of vinylbenzyl chloride into poly(ethylene-$$co$$-tetrafluoroethylene) films using different media

Nuryanthi, N.*; Yamaki, Tetsuya; Kitamura, Akane; Koshikawa, Hiroshi; Yoshimura, Kimio; Sawada, Shinichi; Hasegawa, Shin; Asano, Masaharu; Maekawa, Yasunari; Suzuki, Akihiro*; et al.

Transactions of the Materials Research Society of Japan, 40(4), p.359 - 362, 2015/12

The ion-track grafting of a vinylbenzyl chloride (VBC) into a poly(ethylene-co-tetrafluoroethylene) (ETFE) film is necessary for preparing nanostructured hydroxide-ion-conductive electrolyte membranes. A key for success here is to obtain as high graft levels as possible (for higher conductivity) in a smaller number of tracks (for improving the other membrane properties). To this end, therefore, the effect of the medium for the VBC grafting was investigated as part of our continuing effort to optimize the experimental conditions. A 25 $$mu$$m-thick ETFE film was irradiated in a vacuum chamber with 560 MeV $$^{129}$$Xe at different fluences, and then the grafting was performed by immersing the irradiated films in a 20vol% VBC monomer at 60$$^{circ}$$C. A medium was a mixture of water (H$$_{2}$$O) and isopropyl alcohol (iPrOH) at different volume ratios. The degree of grafting increased as the H$$_{2}$$O content became higher, and reached a maximum in pure H$$_{2}$$O. These results can be explained by considering the well-known Trommsdorff effect, in which poor solubility of the grafted polymer in polar media leads to an increased polymerization rate probably due to a lower termination rate.

Journal Articles

Present status of TIARA at JAEA

Yuyama, Takahiro; Ishibori, Ikuo; Kurashima, Satoshi; Yoshida, Kenichi; Ishizaka, Tomohisa; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Usui, Aya; Miyawaki, Nobumasa; et al.

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.302 - 304, 2015/09

no abstracts in English

Journal Articles

Modification of teflon surface by proton microbeam and nitrogen ion beam

Kitamura, Akane; Sato, Takahiro; Koka, Masashi; Kamiya, Tomihiro; Kobayashi, Tomohiro*

Nuclear Instruments and Methods in Physics Research B, 314, p.82 - 85, 2013/11

 Times Cited Count:5 Percentile:46.51(Instruments & Instrumentation)

Journal Articles

Microscopic evaluation of the absolute fluence distribution of a large-area uniform ion beam using the track-etching technique

Kitamura, Akane; Yamaki, Tetsuya; Yuri, Yosuke; Sawada, Shinichi; Yuyama, Takahiro

Nuclear Instruments and Methods in Physics Research B, 314, p.47 - 50, 2013/11

 Percentile:100(Instruments & Instrumentation)

Journal Articles

Fabrication of micro-prominences on PTFE surface using proton beam writing

Kitamura, Akane; Sato, Takahiro; Koka, Masashi; Kobayashi, Tomohiro*; Kamiya, Tomihiro

Nuclear Instruments and Methods in Physics Research B, 306, p.288 - 291, 2013/07

 Times Cited Count:3 Percentile:62.81(Instruments & Instrumentation)

Journal Articles

Microfabrication on Teflon surface by MeV-proton-microbeam and keV-nitrogen-ion-beam irradiation

Kitamura, Akane; Sato, Takahiro; Koka, Masashi; Kobayashi, Tomohiro*; Kamiya, Tomihiro

Nuclear Instruments and Methods in Physics Research B, 307, p.610 - 613, 2013/07

 Times Cited Count:5 Percentile:46.51(Instruments & Instrumentation)

Journal Articles

Morphological change of self-organized protrusions of fluoropolymer surface by ion beam irradiation

Kitamura, Akane; Kobayashi, Tomohiro*; Sato, Takahiro; Koka, Masashi; Kamiya, Tomihiro; Suzuki, Akihiro*; Terai, Takayuki*

Nuclear Instruments and Methods in Physics Research B, 307, p.614 - 617, 2013/07

 Times Cited Count:4 Percentile:53.77(Instruments & Instrumentation)

Journal Articles

A New microfabrication technique of fluoropolymer was developed, using ion beam

Kitamura, Akane; Sato, Takahiro; Koka, Masashi; Kobayashi, Tomohiro*; Kamiya, Tomihiro

Hoshasen To Sangyo, (134), p.37 - 40, 2013/06

no abstracts in English

Journal Articles

Use of Gafchromic films to measure the transverse intensity distribution of a large-area ion beam

Yuri, Yosuke; Ishizaka, Tomohisa; Yuyama, Takahiro; Ishibori, Ikuo; Okumura, Susumu; Kitamura, Akane; Yamaki, Tetsuya; Sawada, Shinichi

Proceedings of 1st International Beam Instrumentation Conference (IBIC 2012) (Internet), p.531 - 533, 2013/06

Journal Articles

Fabrication of micropatterns on teflon by proton beam writing and nitrogen ion beam irradiation

Kitamura, Akane; Sato, Takahiro; Koka, Masashi; Kamiya, Tomihiro; Kobayashi, Tomohiro*

Transactions of the Materials Research Society of Japan, 38(1), p.101 - 104, 2013/03

72 (Records 1-20 displayed on this page)