Taka–aki Hoshina

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Almost impurity and defect-free barium titanate (BaTiO<sub>3</sub>) nanoparticles with various sizes from 20 to 430 nm were prepared using 2-step thermal decomposition method. The nano-structures of these particles were analyzed using a synchrotron radiation X-ray diffraction (XRD). As a result, it was found that the BaTiO<sub>3</sub> nanoparticles had(More)
Barium titanate (BaTiO<sub>3</sub>) nanoparticles from 27 to 192 nm were prepared by the 2-step thermal decomposition method from barium titanyl oxalate nanoparticles. These particles were dispersed well into 1-propanol and dence BaTiO<sub>3</sub> nanoparticle sphere arrays without stress-field were prepared by the meniscus method. Temperature dependence of(More)
The size effect of BaTiO3 (BTO) is the most important issue to design the high-capacitance MLCCs in the next generation. In the size effect of BTO ceramics and powders, the maxima of the permittivity were observed at certain grain size and the particle size. The permittivity maximum in the ceramics was due to the domain wall contribution, while that in the(More)
The frequency variable microwave microscope was developed to evaluate the dielectric permittivity distribution for dielectrics. The dielectric permittivity and dielectric loss for multi-layer ceramics capacitor were estimated from their microwave reflection intensities at the minimum intensity points. The two dimensional dielectric permittivity image for(More)
Silver lithium niobate (Ag<sub>1-x</sub>Li<sub>x</sub>NbO<sub>3</sub> ALN) single crystals with Li contents of 10 and 12.5 mol% were successfully grown by a slow cooling method. The high-energy X-ray diffraction measurement revealed that the crystal structures of both ALN10 and ALN12.5 were assigned to the coexistence between orthorhombic Pc2<sub>1</sub>b(More)
Barium titanate (BaTiO<sub>3</sub>) nanocube particles below 20 nm were prepared by solvothermal method To prepare nanocubes, a selection of organic solvent and inorganic materials of Ba and Ti sources was most important. At the temperatures above 200degC, a nucleation and particle growth of BaTiO<sub>3</sub> nanoparticles led to a formation of the(More)
The limiting ionic conductivities for the alkali metal and halide ions in methanol are reported and compared with the Hubbard–Onsager (HO) dielectric friction theory based on the continuum model along the liquid–vapor coexsistence curve at temperatures –15°C t 240°C and the reduced densities 2.989 r 1.506. At r > 2.0, the ionic friction coefficients in(More)
A new measurement system of electro-optical (EO) effect and dielectric permittivity (¿r) was developed to investigate the correlation between electro-optic and dielectric properties of epitaxial barium strontium titanate, Ba1-¿Sr¿TiO3 (BST) thin films grown on SrTiO3 (STO) substrates. The refractive index (birefringence) and the permittivity were measured(More)
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