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Yamaki, Tetsuya; Nuryanthi, N.*; Koshikawa, Hiroshi; Asano, Masaharu; Sawada, Shinichi; Hakoda, Teruyuki; Maekawa, Yasunari; Voss, K.-O.*; Severin, D.*; Seidl, T.*; et al.
Nuclear Instruments and Methods in Physics Research B, 314, p.77 - 81, 2013/11
Times Cited Count：3 Percentile：26.71(Instruments & Instrumentation)Ion-track membranes of poly(vinylidene fluoride) (PVDF), a type of fluoropolymer, could find wide applications due to its superior chemical and mechanical properties. In order to produce track-etched pores in PVDF films, we have independently employed much milder etching conditions without any oxidant additives in the alkaline etching solution. The goal of this work is to pursue the possibility of varying beam parameters and applying the effect of the etching pretreatment to control the pore size and shape. Ongoing in-situ/on-line analyses at the M-branch of the UNILAC would shed light on the detailed chemistry of not only ion-induced degradation but also the post-irradiation reactivity.
Yamaki, Tetsuya; Nuryanthi, N.*; Koshikawa, Hiroshi; Asano, Masaharu; Sawada, Shinichi; Hasegawa, Shin; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
Transactions of the Materials Research Society of Japan, 37(2), p.223 - 226, 2012/06
The aim of this study is to investigate the formation of the poly(vinylidene fluoride) (PVDF) track membranes in detail by electrolytic conductometry. A PVDF film was irradiated with a 450 MeV 
Xe or 2.2 GeV 
Au ion beam, and then the latent tracks were etched in a 9 mol dm
aqueous KOH solution at 80
C that had been poured into a conductometric cell. At the same time, the evolution of cylindrical nanopores was monitored by measuring the conductance through the membrane. The etching kinetics significantly depended on the deposited energy within each track, which is represented by the LET. Interestingly, applying a higher voltage to the cell promoted track etching up to the breakthrough probably because the electrophoretic migration of dissolved products occurred out of each pore.
Yamaki, Tetsuya; Nuryanthi, N.*; Koshikawa, Hiroshi; Asano, Masaharu; Sawada, Shinichi; Hasegawa, Shin; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
ECS Transactions, 35(24), p.1 - 12, 2011/05
Times Cited Count：7 Percentile：94.05(Electrochemistry)Our focus has been placed on ion track membranes of poly(vinylidene fluoride) (PVDF), a type of fluoropolymer, because of their superior chemical, mechanical and ferro-electric properties. The aim of this study is to investigate the formation of the PVDF track membranes in more detail by electrolytic conductometry. Interestingly, application of a higher voltage to the conductometry cell as well as irradiation with a higher-LET beam promoted track etching up to breakthrough probably because electrophoretic migration of dissolved products occurred out of each pore.
Nuryanthi, N.*; Yamaki, Tetsuya; Koshikawa, Hiroshi; Asano, Masaharu; Enomoto, Kazuyuki; Sawada, Shinichi; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
Denki Kagaku Oyobi Kogyo Butsuri Kagaku, 78(2), p.146 - 149, 2010/02
Times Cited Count：6 Percentile：13.71(Electrochemistry)Poly(vinylidene fluoride) (PVDF) membranes with conical and cylindrical nanopores were prepared in a controlled manner by the ion-track technique, which involved heavy ion beam irradiation and the subsequent alkaline etching. Etching behavior mainly depended on energy deposition of ion beams, and thus its depth distribution, estimated by theoretical simulation, was successfully applied to control the shapes and diameters of the etched pores. Scanning electron microscopy (SEM) and electrolytic conductometry then gave an insight into critical experimental parameters. Interestingly, applying a higher voltage to the conductometry cell promoted track etching up to breakthrough probably because electrophoretic migration of dissolved products occurred out of each pore.
Rohani, R.*; Yamaki, Tetsuya; Koshikawa, Hiroshi; Takahashi, Shuichi*; Hasegawa, Shin; Asano, Masaharu; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
Nuclear Instruments and Methods in Physics Research B, 267(3), p.554 - 559, 2009/08
Times Cited Count：14 Percentile：66.94(Instruments & Instrumentation)We investigated how pretreatment and high-LET beam irradiation affected the ion-track dissolution rate in poly(vinylidene fluoride) (PVDF) films by SEM observations and conductometric analysis in order to develop the preparation methodology of nano-sized ion-track membranes. PVDF thin films irradiated with four types of ion beams were exposed to a 9 M KOH aqueous solution after their storage in air at 120C. This heating treatment was found to enhance the etch rate in the latent track, both in the inner core and outer halo regions, without changing that in the bulk, probably due to the formation of parasitic oxidation products facilitating the introduction of the etching agent to improve the etchability. Additionally, the irradiation of heavier higher-LET ions, causing each track to more activated sites (like radicals), was preferable for achieving effective etching.
irradiated with high-energy ions by means of X-ray diffraction measurementIshikawa, Norito; Chimi, Yasuhiro; Michikami, Osamu*; Ota, Yasuyuki*; Ohara, Kota; Lang, M.*; Neumann, R.*
Nuclear Instruments and Methods in Physics Research B, 266(12-13), p.3033 - 3036, 2008/06
Times Cited Count：43 Percentile：92.4(Instruments & Instrumentation)Cerium dioxide films are irradiated with high-energy heavy ions with the energy range of 150 MeV to 2.7 GeV, and X-ray diffraction profile is examined. As a result, the data can be explained by creation of nanometer-size ion track with disordered lattice structure, and the ion track is oxygen deficient.
Yamaki, Tetsuya; Rohani, R.*; Koshikawa, Hiroshi; Takahashi, Shuichi; Hasegawa, Shin; Asano, Masaharu; Voss, K.-O.*; Neumann, R.*; Maekawa, Yasunari
Kobunshi Rombunshu, 65(3), p.273 - 276, 2008/03
Times Cited Count：3 Percentile：10.77(Polymer Science)Poly(vinylidene fluoride) thin films irradiated with four kinds of ion beams were exposed to a 9 M KOH aqueous solution after their storage in air for 30 or 90 days at different temperatures. According to the conductometry, the heating at 120ºC was found to enhance the etch rate in the latent track without changing that in the bulk, thereby enabling us to obtain very high etching sensitivity for the preparation of nano-sized through-pores. The formation of hydroperoxides during this pretreatment should facilitate the introduction of the etching agent to improve etchability. Additionally, the irradiation of higher-LET ions, causing each track to more activated sites (like radicals), was preferable to achieve high sensitivity of the etching.
-phenylene terephthalamide); Control of pore shape by irradiation with different ion beamsSuzuki, Yasuyuki; Yamaki, Tetsuya; Koshikawa, Hiroshi; Asano, Masaharu; Voss, K.-O.*; Neumann, R.*; Yoshida, Masaru
Nuclear Instruments and Methods in Physics Research B, 260(2), p.693 - 695, 2007/07
Times Cited Count：13 Percentile：66.15(Instruments & Instrumentation)The preparation of ion-track membranes of thermally stable poly(p-phenylene terephthalamide) was performed by ion beam irradiation followed by chemical etching with a sodium hypochlorite solution. Cylindrical pores were observed in the membrane irradiated with Au and 
U ions at an energy of 11.1 MeV/n. In contrast, funnel shape pores appeared in the membrane irradiated with 
Kr, 
Ru and Xe ion at energies of 6.2, 3.6 and 3.5 MeV/n, respectively. The Au and U ion irradiation was found to exhibit more than four times larger sensitivity to the track etching under the same etching conditions. Consequently, the pore shape can be controlled by the masses and energies of the irradiated ions, in close relation to the etching sensitivity of the track.
-phenylene terephthalamide)Yamaki, Tetsuya; Asano, Masaharu; Maekawa, Yasunari; Suzuki, Yasuyuki; Yoshida, Masaru; Neumann, R.*; Voss, K.-O.*
GSI Report 2007-1, P. 332, 2007/06
The preparation of ion-track membranes of thermally stable poly(-phenylene terephthalamide) (PPTA) was performed by ion beam irradiation followed by chemical etching with a sodium hypochlorite solution. Cylindrical pores were observed in the membrane irradiated with Au and U ions at an energy of 11.1 MeV/n. In contrast, funnel shape pores appeared in the membrane irradiated with Kr, Ru and Xe ion at energies of 6.2, 3.6 and 3.5 MeV/n, respectively. The effect of the ion velocity as well as of the LET in the damage creation might be manifested for the present etched tracks.
Lang, M.*; Hasenkamp, W.*; Ishikawa, Norito; Medvedev, N.*; Neumann, R.*; Papal
o, R.*; Trautmann, C.*; Voss, K.-O.*; Yamaki, Tetsuya
GSI Report 2007-1, P. 313, 2007/06
We report how the ion charge state affects the track morphology of phlogopite, a dark mica mineral. The phlogopite samples were irradiated with nickel-58 ions at three different accelerators (GSI, Tokai/JAEA, and Takasaki/JAEA). The charge state of the Ni beams from both the JAEA accelerators was non-equilibrium, whereas at GSI it was adjusted to the equilibrium by passing the ions through three Al-foils. After chemical etching in a hydrogen fluoride aqueous solution, the tracks from different charge states of +15 (388 MeV) and +23 (373 MeV) were inspected by scanning force microscopy. The significant difference in etch-pit size and shape indicates the direct influence of the charge state in the track morphology.
Yamaki, Tetsuya; Hiroki, Akihiro; Asano, Masaharu; Maekawa, Yasunari; Voss, K.-O.*; Neumann, R.*; Yoshida, Masaru
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 35, 2007/02
no abstracts in English
Fukuzumi, Masafumi*; Chimi, Yasuhiro; Ishikawa, Norito; Suzuki, Motohiro*; Takagaki, Masafumi*; Mizuki, Junichiro; Ono, Fumihisa*; Neumann, R.*; Iwase, Akihiro*
Nuclear Instruments and Methods in Physics Research B, 245(1), p.161 - 165, 2006/04
Times Cited Count：17 Percentile：74.61(Instruments & Instrumentation)We have performed swift heavy ion irradiations in Fe-50at.%Rh alloys at room temperature. Before and after the irradiations, the magnetic properties and the lattice structure are measured using Superconducting QUantum Interference Device (SQUID) and X-Ray Diffractometer (XRD), respectively. We have also performed X-ray Magnetic Circular Dichroism (XMCD) measurement near the Fe K-edge at the synchrotron radiation facility, SPring-8, to examine the irradiation-induced ferromagnetic state near the specimen surface. We have found that the swift heavy ion irradiations induce the ferromagnetic state in Fe-50at.%Rh alloy below the antiferromagnetism-ferromagnetism transition temperature of the unirradiated alloy and the lattice expasion by 0.3%. For the specimens irradiated with swift heavy ions, we observe the XMCD spectra correponding to ferromagnetisim, which depend on the mass of irradiating ions and/or irradiation fluence. Effects of energy loss through electronic excitation and elastic collisions on lattice and magnetic structures of Fe-Rh alloy are discussed.
Iwase, Akihiro; Hamatani, Yutaro*; Mukumoto, Yoshinori*; Ishikawa, Norito; Chimi, Yasuhiro; Kambara, Tadashi*; M
ller, C.*; Neumann, R.*; Ono, Fumihisa*
Nuclear Instruments and Methods in Physics Research B, 209(1-4), p.323 - 328, 2003/08
Times Cited Count：20 Percentile：77.2(Instruments & Instrumentation)Fe=Ni Invar alloy is irradiated with GeV Xe and U ions at room temperature. By the irradiation, the Curie temperature of the soecimens increases, which is correlated with the electronic stopping power. This phenomenon can be explained as due to the lattice expansion and/or the local increase in Ni concentration.
-scaling of lattice parameter change in high ion-velocity region (
2.6
10
cm/s) in ion-irradiated EuBaCu
O
Ishikawa, Norito; Iwase, Akihiro; Chimi, Yasuhiro; Michikami, Osamu*; Wakana, Hironori*; Hashimoto, Takeo*; Kambara, Tadashi*; Mller, C.*; Neumann, R.*
Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.278 - 282, 2002/06
Times Cited Count：8 Percentile：47.9(Instruments & Instrumentation)Swift heavy ions with wide energy range of 80MeV-3.84GeV have been irradiated to EuBaCuO oxide superconductors, and the lattice parameter change due to elecronic excitation has been measured. In the high ion-velocity region, the change in lattice parameter per unit fluence varies as the 4th power of the electronic stopping power. However, in the low-velocity region, the deviation from the 4th power dependence is observed. The results are analyzed by using the primary ionization rate, and it is found that the results support that the Coulomb explosion triggers the atomic displacements.
and NdM between 1-6 and 4°K; Neumann, H. H.*; Craig, R. S.*; N.Mstzouk*; W.E.Wallace*
Journal of Physics and Chemistry of Solids, 32, p.2788 - 2790, 1972/00
Times Cited Count：5no abstracts in English
, CeIn and PrIn at Temperatures Between 1
5 and 42KNasu, Shoichi; Van Diepen, A. M.*; Neumann, H. H.*; Craig, R. S.*
Journal of Physics and Chemistry of Solids, 32(12), p.2773 - 2777, 1971/00
Times Cited Count：28no abstracts in English
; Neumann, H. H.*; N.Mstzouk*; Craig, R. S.*; W.E.Wallace*
Journal of Physics and Chemistry of Solids, 32, p.2779 - 2783, 1971/00
Times Cited Count：42no abstracts in English
Yamaki, Tetsuya; Koshikawa, Hiroshi; Hasegawa, Shin; Asano, Masaharu; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
no journal, ,
Poly(vinylidene fluoride) (PVDF) thin films were irradiated with different kinds of ion beams and then exposed to a 9 M KOH aqueous solution. Based on the results of SEM observations and conductometric analyses, the heating at 120C was found to enhance the etch rate in the latent track without changing that in the non-irradiated part, thereby enabling us to obtain very high etching sensitivity for the preparation of nano-sized pores. The formation of oxidized species during this pretreatment should facilitate the introduction of the etching agent to improve etchability. Additionally, the irradiation with higher-mass ions was preferable to achieve high sensitivity of the etching.
Yamaki, Tetsuya; Nuryanthi, N.; Koshikawa, Hiroshi; Sawada, Shinichi; Hasegawa, Shin; Asano, Masaharu; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
no journal, ,
Although the ion-track technique has mainly been studied on a series of hydrocarbon polymers such as polycarbonate and polyethylene terephthalate, our focus has been placed on ion track membranes of poly(vinylidene fluoride) (PVDF), a type of fluoropolymers, because of superior chemical, mechanical and ferro-electric properties. In this study, PVDF membranes with conical and cylindrical nanopores were prepared in a controlled manner by the ion-track technique, which involved ion-beam irradiation and the subsequent alkaline etching. Etching behavior mainly depended on energy deposition of ion beams, and thus its depth distribution, estimated by theoretical simulation, was successfully applied to control the shapes and diameters of the etched pores.
Yamaki, Tetsuya; Nuryanthi, N.; Koshikawa, Hiroshi; Sawada, Shinichi; Hasegawa, Shin; Asano, Masaharu; Maekawa, Yasunari; Voss, K.-O.*; Trautmann, C.*; Neumann, R.*
no journal, ,
Poly(vinylidene fluoride) (PVDF) membranes with conical and cylindrical nanopores were prepared in a controlled manner by the ion-track technique, which involved heavy ion beam irradiation and subsequent alkaline etching. The etching behavior mainly depended on the energy deposition of the ion beams, and thus its depth distribution, estimated by theoretical simulation, was successfully applied to control the shapes and diameters of the etched pores. Scanning electron microscopy (SEM) and electrolytic conductometry provided an insight into the critical experimental parameters.
