Publications by authors named "Yasuhiro Yoneda"

Barium titanate (BaTiO) nanocubes with a narrow particle size distribution were synthesized using a three-step approach. First, a water-soluble Ti complex was synthesized using a hydrolysis method. Next, the titanium dioxide (TiO) raw material was synthesized via a hydrothermal method using various water-soluble titanium (Ti) complexes.

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Crystal growth of barium titanate (BaTiO) using a wet chemical reaction was investigated at various temperatures. BaTiO nanoparticles were obtained at an energy-efficient temperature of 80 °C. However, BaTiO nanocubes with a preferred size and shape could be synthesized using a solvothermal method at 200 °C via a reaction involving titanium tetraisopropoxide [(CH)CHO]Ti for nucleation and fine titanium oxide (TiO) nanoparticles for crystal growth.

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The determination of local atomic structure at nanoscale for inhomogeneous systems is challenging. The local arrangement of atoms needs to be studied to understand the local or short-range order structures for disordered materials with a lack of long-range order periodicity. Pair distribution function (PDF) analysis is a technique, that is used to study the short-range order structure of materials: this technique is based on the evaluation of local atomic arrangement using synchrotron and neutron sources.

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To stabilise ferroelectric-tetragonal phase of BaTiO, the double-doping of Bi and Mn up to 0.5 mol% was studied. Upon increasing the Bi content in BaTiO:Mn:Bi, the tetragonal crystal-lattice-constants a and c shrank and elongated, respectively, resulting in an enhancement of tetragonal anisotropy, and the temperature-range of the ferroelectric tetragonal phase expanded.

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The magnetic and dielectric properties of InFe2O4, InFeCuO4, and InGaCuO4 have been investigated. All these materials are isostructural with RFe2O4 (R = Y, Ho-Lu), which shows ferroelectricity due to iron-valence ordering. InFe2O4 exhibits ferrimagnetic ordering at T(C) approximately 242 K and a dielectric constant (epsilon) of approximately 10,000 at around room temperature.

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The purposes of this study are to construct a simple dioxin detection system using peptides that bind to dioxin, and to test the system on real environmental samples. In this method, dioxin and N-NBD-3-(3',4'-dichlorophenoxy)-1-propylamine (NBD-DCPPA) are competitively bound to the peptides synthesized on beads. The fluorescence intensity of the bead decreases with increasing dioxin concentration.

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