Determination of alkali and alkaline earth elements in radioactive waste generated from reprocessing plant by liquid electrode plasma optical emission spectrometry

Yamamoto, Masahiko; Do, V. K.; Taguchi, Shigeo; Kuno, Takehiko; Takamura, Yuzuru*

Journal of Radioanalytical and Nuclear Chemistry, 327(1), p.433 - 444, 2021/01

https://doi.org/10.1007/s10967-020-07490-1

A simple, practical, and reliable analytical method for determination of Na, K, Ca, Sr, and Ba by liquid electrode plasma optical emission spectrometry is developed. Appropriate emission lines for quantification, interferences from co-existing elements, and effect of measurement conditions with cell damage have been investigated. The spike and recovery tests using actual sample have been performed for method validation, and negligible sample matrix effect has been observed. Consequently, the method is successfully applied to several radioactive wastes. The obtained data have been agreed well with data from computer calculation and inductively coupled plasma optical emission spectrometry within 10% difference.

Structure of active sites of Fe-N-C nano-catalysts for alkaline exchange membrane fuel cells

Kishi, Hirofumi*; Sakamoto, Tomokazu*; Asazawa, Koichiro*; Yamaguchi, Susumu*; Kato, Takeshi*; Zulevi, B.*; Serov, A.*; Artyushkova, K.*; Atanassov, P.*; Matsumura, Daiju; et al.

Nanomaterials (Internet), 8(12), p.965_1 - 965_13, 2018/12

https://doi.org/10.3390/nano8120965

Preparation of -LiVO from polyoxovanadate cluster Li[VO(CO)] as a high-performance cathode material and its reaction mechanism revealed by XAFS

Wang, H.*; Idobe, Jin*; Shimizu, Takeshi*; Matsumura, Daiju; Ina, Toshiaki*; Yoshikawa, Hirofumi*

Journal of Power Sources, 360, p.150 - 156, 2017/08

https://doi.org/10.1016/j.jpowsour.2017.06.011

Wetting induced oxidation of Pt-based nano catalysts revealed by high energy resolution X-ray absorption spectroscopy

Cui, Y.-T.*; Harada, Yoshihisa*; Niwa, Hideharu*; Hatanaka, Tatsuya*; Nakamura, Naoki*; Ando, Masaki*; Yoshida, Toshihiko*; Ishii, Kenji*; Matsumura, Daiju; Oji, Hiroshi*; et al.

Scientific Reports (Internet), 7(1), p.1482_1 - 1482_8, 2017/05

https://doi.org/10.1038/s41598-017-00639-1

Electrical conductivity increase of Al-doped ZnO films induced by high-energy-heavy ions

Sugai, Hiroyuki; Matsunami, Noriaki*; Fukuoka, Osamu*; Sataka, Masao; Kato, Teruo; Okayasu, Satoru; Shimura, Tetsuo*; Tazawa, Masato*

Nuclear Instruments and Methods in Physics Research B, 250(1-2), p.291 - 294, 2006/09

https://doi.org/10.1016/j.nimb.2006.04.126

We have investigated the effects on electrical properties of Al-doped ZnO (AZO) semiconductor films induced by high-energy heavy ion. The AZO films with c-axis on SiO glass substrate were prepared by a RF-sputter-deposition method at 400 C. Rutherford backscattering spectroscopy shows that the Al/Zn composition and the film thickness are 4 % and 0.3 m. We find that the conductivity monotonically increases from 1.510 to 810 S/cm with increasing the fluence up to 410/cm, as already been observed for 100 keV Ne irradiation. The fluence of 100 keV Ne at which the conductivity takes its maximum is 310/cm (7 dpa). The dpa of 100 MeV Xe at 410/cm is estimated as 0.008. Hence, the conductivity increase by 100 MeV Xe ion is ascribed to the electronic excitation effects.

Electrochemical behavior of actinides and actinide nitrides in LiCl-KCl eutectic melts

Shirai, Osamu*; Yamana, Hajimu*; Arai, Yasuo

Journal of Alloys and Compounds, 408-412, p.1267 - 1273, 2006/02

https://doi.org/10.1016/j.jallcom.2005.04.119

no abstracts in English

Rapid and quantitative electrolytic preparation and speciation of neptunium ions of various oxidation states using multi-step column electrodes

Aoyagi, Hisao*; Kitatsuji, Yoshihiro; Yoshida, Zenko; Kihara, Sorin*

Analytica Chimica Acta, 538(1-2), p.283 - 289, 2005/05

https://doi.org/10.1016/j.aca.2005.02.035

Redox behavior of Np(III), (IV), (V) and (VI) ions in aqueous perchloric, nitric and sulphuric acid solutions was elucidated by using column electrodes connected in series in a flow system. Using a glassy carbon fiber working electrode as the column electrode was found to be very useful for the investigation of current-potential relations of not only reversible redox processes such as Np(VI)/(V) or Np(IV)/(III) but also irreversible processes such as Np(V)/(IV) or Np(V)/(III), the latter not observed by conventional voltammetry which uses a glassy carbon or platinum electrode. Quantitative electrolysis could be executed even if the redox process was completely irreversible by the use of the column electrodes. By taking advantage of column electrode electrolysis, a novel method was developed for the rapid preparation of a neptunium species of a desired oxidation state, including unstable species. The multi-step column electrode system was demonstrated to be useful for the coulometric determination and speciation of Np(IV), (V) and (VI) in aqueous HNO solution as an example.

Trial fabrication of BeTi electrode for pebble production by rotating electrode method

Uda, Minoru*; Iwadachi, Takaharu*; Uchida, Munenori*; Nakamichi, Masaru*; Kawamura, Hiroshi

JAERI-Conf 2004-006, p.190 - 195, 2004/03

https://jopss.jaea.go.jp/pdfdata/JAERI-Conf-2004-006.pdf

no abstracts in English

Elemental development of beryllide electrode for pebble production by rotating electrode method

Uchida, Munenori*; Uda, Minoru*; Iwadachi, Takaharu*; Nakamichi, Masaru; Kawamura, Hiroshi

Journal of Nuclear Materials, 329-333(Part2), p.1342 - 1346, 2004/00

https://doi.org/10.1016/j.jnucmat.2004.04.195

In this paper, an elemental technology to fabricate beryllide rods by the vacuum casting was researched. Furnace material study to prevent the chemical reaction with beryllide and casting procedure study to cast durable ingot without any shrinkages and cracks were performed. From the results of the reactivity test of refractory material with BeTi, it was clear that the BeO crucible had less reactivity with melt and no contamination. From the results of casting tests with a MgO cylindrical mold in a vacuum chamber, it was revealed that the mold dimension was critical to minimize shrinkages and cracks. It was also found that the forced cooling by the MgO cylindrical sleeve with water-cooled copper mold on the bottom was efficient to improve the shrinkages and the cracks.

Evaluation of the characteristics of silicon carbide diodes using transient-IBIC technique

Oshima, Takeshi; Lee, K. K.; Onoda, Shinobu*; Kamiya, Tomihiro; Oikawa, Masakazu*; Laird, J. S.; Hirao, Toshio; Ito, Hisayoshi

Nuclear Instruments and Methods in Physics Research B, 210, p.201 - 205, 2003/09

https://doi.org/10.1016/S0168-583X(03)01070-X

Electrodes on SiC pn diode were studied uising Transient Ion Beam Induced Current system (TIBIC). pn junction of SiC diode was formed by phosphorus ion implantation at 800 C and subsequent annealing at 1800 C for 1 min in Ar. Electrodes of diode were fabricated (1) Al evaporation and sintering at 850 C or (2) one more Al evaporation after the process mentioned above. TIBIC measurement using 15 MeV-O and 12 MeV-Ni ion micro beam. As the result, non-uniformity for transient current from the electrodes of diode (1)was observed. As for diode (2), such non-uniformity was not observed. On the other hand, the value of collected charges was the same for both diodes. This indicates that the quality of pn junction is the almost same for both diodes. For current-voltage characteristics, both diodes showed a order of pA at reverse bias of 30 V and turn-on at forward bias of 2V which are ideal for SiC diode. Thus, we can conclude that we obtain the information on electrical characteristics of electrodes which is not obtained from normal current-voltage measurement.