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Papers by Akihiko Kajinami

Lanthanoborate glasses ((La 2 O 3 ) x (B 2 O 3 ) 1−x glasses, where x = 0.22, 0.25, 0.28, 0.30) w... more Lanthanoborate glasses ((La 2 O 3 ) x (B 2 O 3 ) 1−x glasses, where x = 0.22, 0.25, 0.28, 0.30) were prepared by rapid-quenching method using twinroller apparatus. The composition dependence of the local structure in the lanthanoborate glasses was investigated by Raman spectroscopy, XAFS and XPS measurements. The XAFS measurements of La LIII-edge showed that the lanthanum ion is surrounded by nine oxygen atoms and that the La-O distance decreases with increasing of the La 2 O 3 content, which shows that the La-O interaction becomes stronger with increasing of the La 2 O 3 content. The corresponding result was obtained from XPS spectra for La 3d 3/2 and 3d 5/2 . The Raman spectra showed a band at ca. 761 cm −1 which is assigned to metaborate chain structure. It is found that the band decreases with increasing of La 2 O 3 content. The bands at 635, 835, and 925 cm −1 increase with increasing of La 2 O 3 content, which are assigned to small anionic units, such as metaborate ring, pyroborate, and orthoborate structure, respectively, which shows that the network structure in the glasses changes to small anionic units as the La 2 O 3 content increases.

$Research paper thumbnail of Pulsed Neutron Diffraction Study of Molten CsCl-NaCl-YCl3: Approaches from Fundamentals to Pyrochemical Reprocessing$

Gaune-Escard/Molten Salts Chemistry and Technology, 2014

ABSTRACT

Progress in Nuclear Energy, 2011

ABSTRACT A specified technique using X-ray from synchrotron sources was developed to contribute t... more ABSTRACT A specified technique using X-ray from synchrotron sources was developed to contribute the optimization of the condition of electrodeposition directly. For this purpose, the design of the confinement equipped with electrodes has been optimized. Some case studies such as an alloy formation of Ce with Ni have been examined in-situ under the X-ray irradiation. Still a lot of tasks remains to apply the real system of electrolyzer, by the combination of XAFS and imaging technique, redox reactions occurring inside the un-visible confinements would be well identified.

Solid State Ionics, 2002

The deposition process of iron oxyhydroxide (β-FeOOH) from aqueous solution system of FeOOH–NH4F·... more The deposition process of iron oxyhydroxide (β-FeOOH) from aqueous solution system of FeOOH–NH4F·HF (aq.) with H3BO3 by the liquid phase deposition (LPD) method has been investigated. The effect of initial concentration in the treatment solution and reaction time on microstructure and orientation of the deposited films were studied by means of scanning electron microscope (SEM), X-ray diffraction (XRD) and transmission electron microscope (TEM) observation. The films deposited were constructed by small particles having a crown-like and columnar structure, depending on the concentration range in the treatment solution. XRD measurements revealed that the deposited film preferred the specific direction normal to (211) plane and the dimension of the crystallites varied with the initial concentration of the solution. The deposition process and structure of the films appeared to be strongly affected by the hydrolysis reaction of Fe3+ ions coordinated by F− and/or partial OH− ions by adding boric acid.

Thin Solid Films, 2002

We have prepared polyacrylonitrile (PAN) thin films containing Au nanoparticles by heat treatment... more We have prepared polyacrylonitrile (PAN) thin films containing Au nanoparticles by heat treatment of AuyPAN stacking films. The effect of heat treatment on the microstructure of the composite films was investigated by means of transmittance electron microscopy (TEM), Fourier-transform infrared (FT-IR) and Raman spectroscopy. The Au nanoparticles initially deposited on the PAN film were found to be dispersed into the PAN layer by heat treatment at 200 8C, after which structural changes in the PAN matrix were observed, i.e. decomposition of methylene and nitrile groups into C_N conjugation. It was also found that heat treatment of the films at higher temperatures caused change of the PAN matrix into amorphous carbon. The mean size of the Au nanoparticles increased with increasing heat-treatment temperature. ᮊ

$Research paper thumbnail of The structural analysis of manganese borate glass by high-energy X-ray diffraction measurement$

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2003

Structure of manganese borate glasses (MnO) X (B 2 O 3 ) 1ÀX (X ¼ 0, 0.21, 0.30, 0.35, 0.44) were... more Structure of manganese borate glasses (MnO) X (B 2 O 3 ) 1ÀX (X ¼ 0, 0.21, 0.30, 0.35, 0.44) were investigated by highenergy X-ray diffraction (HEXRD) measurement at 61.5 keV. The composition dependence of the glass structure was discussed with the total correlation functions, T ðrÞ. It was found that the interatomic distance and coordination number of the B-O correlation increases with the increase of the manganese oxide content. The short-range structure of manganese was discussed from the laboratory XAFS measurement. It was found that the manganese ion has tetrahedral structure with oxygen atoms.

Journal of the American Ceramic Society, 2005

... Rev. B, 65, 144302 (2002). CrossRef. 15 R. Brenier, J. Mugnier, and E. Mirica, XPS Study of ... more ... Rev. B, 65, 144302 (2002). CrossRef. 15 R. Brenier, J. Mugnier, and E. Mirica, XPS Study of Amorphous Zirconium Oxide Films Prepared by SolGel,Appl. Sur. Sci., 143 [14] 8591 (1999). ... 36 AE Bohé, J. Andrade-Gamboa, DM Pasquevich, AJ Tolley, and JL Pelegrina ...

Journal of Materials Chemistry, 1997

Journal of Electroanalytical Chemistry, 2005

... by means of high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-... more ... by means of high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray (EDX) analysis with a nano-probe. ... substrate by means of ligand-exchange hydrolysis of a metal-fluoro complex and the F − consumption reaction with boric acid or aluminum ...

Journal of Colloid and Interface Science, 1993

$Research paper thumbnail of Local structure of molten LaCl3 analyzed by X-ray diffraction and La–LIII absorption-edge XAFS technique$