Refine your search:     
Report No.
 - 
Search Results: Records 1-15 displayed on this page of 15
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

High-temperature X-ray imaging study of simulated high-level waste glass melt

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*

Denki Kagaku Oyobi Kogyo Butsuri Kagaku, 81(7), p.543 - 546, 2013/07

 Times Cited Count:6 Percentile:18.03(Electrochemistry)

The molten state of simulated high-level waste glass and the behavior of ruthenium element in the melt were investigated by using synchrotron radiation based X-ray imaging technique. Melting, generating and moving of bubbles, condensation and sedimentation of ruthenium element were observed dynamically in continuous 12-bit gray-scale images from the CCD camera. X-ray intensity was obtained easily by digitizing gray-scale values in the image. The existence of ruthenium element is emphasized as a black color in the CCD image at X-ray energy higher than the Ru K-absorption edge. Position sensitive imaging X-ray absorption fine structure (XAFS) measurement was also performed to clarify the chemical state of ruthenium element in the melt.

Journal Articles

High-temperature X-ray imaging study of simulated high-level waste glass melt

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*

Proceedings of 4th Asian Conference on Molten Salt Chemistry and Technology & 44th Symposium on Molten Salt Chemistry, Japan, p.47 - 52, 2012/09

The molten state of the simulated high-level waste glass and the behavior of ruthenium element in the melt were investigated by using synchrotron radiation based X-ray imaging technique. Melting, generating and moving of bubbles, condensation and sedimentation of ruthenium element were observed dynamically in continuous 12-bit gray-scale images from the CCD camera. The existence of ruthenium in the X-ray CCD image was emphasized over the energy of Ru K-absorption edge. X-ray intensity was obtained easily by digitalizing gray-scale values in the image. Position sensitive imaging X-ray absorption fine structure (XAFS) measurement was performed to clarify the chemical state of ruthenium element in the melt.

Journal Articles

Synchrotron radiation-based X-ray imaging study of ruthenium in simulated high-level waste glass

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Shiwaku, Hideaki; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*

Nihon Genshiryoku Gakkai Wabun Rombunshi, 11(2), p.127 - 132, 2012/06

Distribution and the chemical state of Ru element in the simulated high-level waste glass were examined by using the synchrotron radiation based X-ray imaging technique. In this technique, a direct X-ray CCD camera is used in place of an ion chamber. Position sensitive X-ray absorption spectra were obtained by analyzing gray scale in images of the X-ray CCD camera. At first, we measured a test sample containing RuO$$_2$$ and Ru metal powder. We successfully obtained information on the Ru distribution in the sample. In addition, the chemical state (oxide or metal ?) of each small Ru-rich spot was evaluated by the corresponding position sensitive XAFS spectrum. The imaging XAFS technique was applied to some simulated high-level waste glass samples. The Ru distribution of the glass sample and their chemical state were confirmed by image analyses. It can be seen that Ru element scattered in the glass sample exists as oxide RuO$$_2$$.

Journal Articles

Quantum beam technology; Nanostructured proton-conductive membranes prepared by swift heavy ion irradiation for fuel cell applications

Yamaki, Tetsuya; Kobayashi, Misaki*; Asano, Masaharu; Nomura, Kumiko*; Takagi, Shigeharu*; Maekawa, Yasunari; Yoshida, Masaru*

Proceedings of Sadoway 60 Symposium, p.114 - 120, 2010/06

My presentation deals with the application of high-energy heavy ion beams from the cyclotron accelerator of Takasaki Ion Accelerators for Advanced Radiation Application (TIARA), JAEA. Our strategic focus is centered on using nano-scale controllability of the ion-beam processing; the membrane preparation involves (1) the irradiation of commercially-available base polymer films with hundreds of MeV ions, (2) graft polymerization of vinyl monomers into electronically-excited parts along the ion trajectory, called latent tracks, and (3) sulfonation of the graft polymers. Interestingly, the resulting membranes exhibited anisotropic proton transport, i.e., higher conductivity in the thickness direction. According to microscopic observations, this is probably because the columnar electrolyte phase extended, with a width of tens-to-hundreds nanometers, through the membrane.

Oral presentation

Development of polymer electrolyte membranes by ion-beam irradiation technique for fuel cell applications

Yamaki, Tetsuya; Kobayashi, Misaki*; Asano, Masaharu; Yoshida, Masaru; Nomura, Kumiko*; Takagi, Shigeharu*; Maekawa, Yasunari

no journal, , 

Fluoropolymer films were bombarded with swift heavy ions to produce an activated zone along the incident axis. The chemically active species generated in this so-called ion track were used to initiate the grafting of styrene, and the subsequent sulfonation of the graft chains provided the electrolyte membranes with anisotropic proton conductivity in the thickness direction. These membranes were found to have sufficient mechanical strength as well as highly conductive pathways with a cylindroidal shape of tens-to-hundreds nanometer size.

Oral presentation

Development of nanostructure-controlled fuel-cell membranes by ion irradiation technique

Kobayashi, Misaki*; Yamaki, Tetsuya; Nomura, Kumiko*; Takagi, Shigeharu*; Asano, Masaharu; Yoshida, Masaru; Maekawa, Yasunari

no journal, , 

To realize mass commercialization of fuel cell, many kinds of properties, such as high proton conductivity, low water swelling and high mechanical strength, are required for a polymer electrolyte membrane. Utilizing nano-scale controllability of an ion beam is our strategic way for the preparation of fuel-cell electrolyte membranes. The preparation of membranes involve (1) the irradiation of heavy ions with different masses and energies; (2) the grafting of styrene into electronically-excited region along the ion trajectory called the latent track; (3) sulfonation of the graft chains. According to the FE-SEM and TEM observations, the proton conductive electrolyte part appeared to extend through the membrane thickness with dimensions of tens-to-hundreds nanometers, which agreed with the calculated latent track diameter. Correlations between membrane properties, such as proton conductivity and nanostructure were investigated.

Oral presentation

Development of nano-structure controlled polymer electrolyte fuel-cell membranes by high-energy heavy ion irradiation

Yamaki, Tetsuya; Asano, Masaharu; Kobayashi, Misaki*; Nomura, Kumiko*; Takagi, Shigeharu*; Maekawa, Yasunari; Yoshida, Masaru

no journal, , 

In order to develop proton-conductive membranes for PEFCs, we have been using high-energy heavy ion beams from the cyclotron accelerator of TIARA. Our strategic focus is centered on using nano-scale controllability of the ion-beam processing; the membrane preparation involves (1) the irradiation of commercially-available base polymer films with MeV ions, (2) graft polymerization of vinyl monomers into electronically-excited parts along the ion trajectory, called latent tracks, and (3) sulfonation of the graft polymers. Interestingly, the resulting membranes exhibited anisotropic proton transport, i.e., higher conductivity in the thickness direction. According to microscopic observations, this is probably because the columnar electrolyte phase extended, with a width of tens-to-hundreds nanometers, through the membrane. Other excellent membrane properties, e.g., sufficient mechanical strength, high dimensional stability, and low gas permeability should be due to such a controlled structure.

Oral presentation

Development of fuel-cell polymer electrolyte membranes by ion track technology

Yamaki, Tetsuya; Asano, Masaharu; Kobayashi, Misaki*; Nomura, Kumiko*; Takagi, Shigeharu*; Maekawa, Yasunari; Yoshida, Masaru

no journal, , 

We have been using high-energy heavy ion beams from the cyclotron accelerator of Takasaki Ion Accelerators for Advanced Radiation Application (TIARA), JAEA to develop proton-conductive membranes for PEFCs. Our strategic focus is centered on using nano-scale controllability of the ion-beam processing; the membrane preparation involves (1) the irradiation of commercially-available base polymer films with MeV ions, (2) graft polymerization of vinyl monomers into electronically-excited parts along the ion trajectory, called latent tracks, and (3) sulfonation of the graft polymers. Interestingly, the resulting membranes exhibited anisotropic proton transport, i.e., higher conductivity in the thickness direction. According to microscopic observations, this is probably because the columnar electrolyte phase extended, with a width of tens-to-hundreds nanometers, through the membrane. Other excellent membrane properties, e.g., sufficient mechanical strength, high dimensional stability, and low gas permeability should be due to such a controlled structure.

Oral presentation

Chemical state analysis of metals in imitative glasses by using Imaging XAFS technique

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Minato, Kazuo; Shiwaku, Hideaki; Komamine, Satoshi*; Fukui, Toshiki*; Nitani, Hiroaki*; Nomura, Masaharu*

no journal, , 

Chemical state analysis of Ru element scattered in an imitative glass matrix was performed by using the Imaging XAFS technique. Information on distribution of Ru element in the matrix was obtained from contrast values of CCD images before and after the Ru K-absorption edge. It is confirmed that the feature of the distributed element can be examined by getting XAFS spectra from the contrast information. We can get two kinds of XAFS spectra corresponding to Ru metal and oxide separately in the Imaging XAFS analysis.

Oral presentation

Development of nano-structure controlled polymer electrolyte fuel-cell membranes by high-energy heavy ion irradiation

Yamaki, Tetsuya; Kobayashi, Misaki*; Asano, Masaharu; Nomura, Kumiko*; Takagi, Shigeharu*; Maekawa, Yasunari; Yoshida, Masaru*

no journal, , 

Our presentation deals with the application of high-energy heavy ion beams to the preparation of nano-structure controlled electrolyte membranes. The membrane preparation involves (1) irradiation of commercially-available base polymer films with 100 MeV $$^{16}$$O, 400 MeV $$^{56}$$Fe, or 450 MeV $$^{129}$$Xe, (2) graft polymerization of vinyl monomers into latent tracks, and (3) sulfonation of the graft polymers. The resulting membranes exhibited anisotropic proton transport, i.e., higher conductivity in the through-plane direction. According to microscopic observations, this is probably because the nearly columnar electrolyte phase with a width of tens-to-hundreds nanometers extended through the membrane. Interestingly, our ion irradiation technique would be able to control the nano-structure of proton-conducting pathways in the membranes. Other excellent membrane properties should also be due to such a controlled structure.

Oral presentation

Synchrotron radiation based X-ray imaging study of simulated high-level waste glass

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Minato, Kazuo; Shiwaku, Hideaki; Yaita, Tsuyoshi; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; et al.

no journal, , 

Distribution and the chemical state of Ru element in the simulated high-level waste glass were examined by using the synchrotron radiation based X-ray imaging technique. In this technique, a direct X-ray CCD camera is used in place of an ion chamber. Position sensitive X-ray absorption spectra were obtained by analyzing gray scale in images of the X-ray CCD camera. It can be seen that Ru element scattered in the glass sample exists as oxide RuO$$_2$$.

Oral presentation

Development of nano-structure controlled polymer electrolyte fuel-cell membranes by high-energy heavy-ion irradiation; Study of their proton conductivity

Yamaki, Tetsuya; Kobayashi, Misaki*; Asano, Masaharu; Nomura, Kumiko*; Takagi, Shigeharu*; Maekawa, Yasunari; Yoshida, Masaru*

no journal, , 

This study deals with the application of high-energy heavy ion beams from the cyclotron accelerator of Takasaki Ion Accelerators for Advanced Radiation Application (TIARA), JAEA. Our strategic focus is centered on using nano-scale controllability of the ion-beam processing; the membrane preparation involves (1) the irradiation of commercially-available base polymer films with hundreds of MeV ions, (2) graft polymerization of vinyl monomers into electronically-excited parts along the ion trajectory, called latent tracks, and (3) sulfonation of the graft polymers. The resulting membranes exhibited anisotropic proton transport, i.e., higher conductivity in the thickness direction. The through-plane proton conductivity, which is a more direct measurement of the membrane's conductivity and is of interest in an operating fuel cell, was comparable to that of a Nafion112 membrane at the same ion exchange capacity level.

Oral presentation

Synchrotron radiation based imaging XAFS analysis of simulated high-level waste glass

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*

no journal, , 

Distribution and the chemical state of fission product elements like Zr, Mo and Ru in the simulated high-level waste glass were examined by using the synchrotron radiation based X-ray imaging technique. We used the high resolution imaging system and the high-speed CCD camera for imaging XAFS measurement of the glass sample at molten state. Position sensitive X-ray absorption spectra were obtained by analyzing gray scale in images of the CCD camera.

Oral presentation

Chemical analysis of simulated high-level waste glass by using imaging XAFS technique

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*

no journal, , 

The high level liquid waste (HLLW) generated in the reprocessing of spent nuclear fuels is disposed of as vitrified waste mixed with borosilicate glass. Chemical state of noble metals like Ru in simulated glasses was investigated by using the synchrotron based X-ray imaging analysis in the present work. The X-ray imaging measurement was performed at the NW10A of PF-AR and the BL-27B of PF, KEK. The imaging system is composed of the beam monitor (AA40 and AA50) and the CCD camera (high-speed type C9300-221 and high resolution type C11440-10C). X-ray absorption fine structure (XAFS) spetcra of Ru K-edge for very small area were obtained from the imaging intensity data. It can be seen by comparing with standard materials that Ru in the small area exists as RuO$$_2$$.

Oral presentation

Observation of Ru in high-temperature molten simulated glass by X-ray imaging

Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Kawashima, Hidenori*; Komamine, Satoshi*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*

no journal, , 

The molten state of simulated high-level waste glass and the behavior of ruthenium element in the melt were investigated by using synchrotron radiation based X-ray imaging technique. Melting, generating and moving of bubbles, condensation and sedimentation of ruthenium element were observed dynamically in continuous 12-bit gray-scale images from the CCD camera. The imaging XAFS results of our experiment clearly show that the ruthenium in the high temperature glass melt exists as oxide.

15 (Records 1-15 displayed on this page)
  • 1