The change of mechanical quality factor, Q_m as a function of the current density was measured by a electrical transient response in PbZrO₃ - PbTiO₃ - Pb(Mn_1/3Sb_2/3)O₃ piezoelectric ceramics which have different 3rd nonlinear piezoelectric coefficient,ξ_D31 values. For the measurements of Q_m and ξ_D31, the rectangular samples were driven at the fundamental resonance frequency of the length extensional 1/2 λ mode in the constant-current circuit. It was found that the Q_m decreases more clearly with the increase of the current density in the samples having larger ξ_D31.

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A piezo-electric material has the piezo-electric effect and a pyroelectric effect.Moreover, the shape memory alloy has a shape memory effect and the superelastic effect. We succeeded in film forming of the PZT thin film on the surface of the SMA wire, and created the device with these four effects this time.Development of a new compound functional device is possible by using these effects.

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The solid solution (Ba_1-2xBi_2x)(Ti_1-xCu_x)O₃(0≤x≤0.040) was prepared by conventional high temperature reaction. The Curie temperature Tc increased to 145C at the maximum of the c/a with x=0.020. We investigated ferroelectric and piezoelectric properties of the solid solution ceramics.

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We investigate the ferroelectric phase evolution in AgNbO3-KNbO3 solid solutions.In the Ag-rich region, strong ferroelectricity with Pr=25 uC/cm2 was observed in the solid solutions, in which two ferroelectric phases were detected.In the K-rich region, the solid solutions show similar ferroelectric transitions to those of pure KNbO3. A strain level of 0.05% and a d33 value of 46-64 pC/N were also observed for the ceramics samples.

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We report the temperature behaviors of dielectric response in solid solution between quantum ferroelectric (Ba0.767Ca0.233)TiO3(BCTO) and quantum paraelectric SrTiO3(STO). The substitution of BCTO with STO lowers the paraelectric-ferroelectric phase transition temperature as expected. However, in sharp contrast to pure BCTO, in which only tetragonal structure is stable in the ferroelectric phase, BCTO-STO solid solution shows new phase transitions in the ferroelectric phase.

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Sensing characteristics of amperometric NOx sensor using yttria-stabilized zirconia (YSZ) and LaSr-based perovskite-type oxide sensing-electrode (SE) was examined. La0.8Sr0.2MO3(M=Co, Mn, Ni, Fe) was synthesized by means of spray pyrolysis method. The response to NO2 of the sensor using La0.8Sr0.2MnO3-SE was larger than CO, C3H6, NH3 at 600 C in the presence of excess O2 (21%). The sensitivity was increased with increasing NO2 concentration in the examined range between 50 to 800 ppm.

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In order to achieve a high throughput exploration of sensor materials using surface plasmon resonance (SPR), the gas sensing property of a ZnO/Au/SiO2 chip with SPR and the enhancing effect of UV irradiation on the NO2-desorption rate from the ZnO surface were investigated. When the ZnO/Au/SiO2 chip was exposed to a high concentration of NO2 (1000 ppm), a larger peak shift in the SPR curve was observed as compared with that of low-concentration NO2 (10 ppm). From the X-ray photoelectron spectra for N 1s of the ZnO thin films exposed to 1000- and 10-ppm NO2, two chemisorption states were confirmed.

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We studied the relationship between the microstructure and oxygen diffusion in non-doped BaTiO3 ceramics by means of 2-dimensional isotope mapping. The non-doped BaTiO3 ceramics with mirror surface was pre-annealed in air and 3%H2-Ar, before the oxygen annealing. Oxygen isotope mapping was measured in the cross-section of samples, and the results indicated the effect of the atmosphere on the paths of oxygen. The sample pre-annealed in air, the oxygen tracer diffused at the grain boundary. On the contrast to this, in sample annealed in 3%H2-Ar, the grain boundary acted as the barrier of oxygen diffusion, reflecting the presence of the space charge layer at the grain boundary. The atmosphere in the pre-annealing is am important process to control the oxygen diffusion in non-doped BaTiO3.

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Synthesis of La-Co substituted M-type Ca ferrite were studied. Samples were prepared by polymerizable complex method. Phase identification and determination of lattice parameters were carried out by powder X-ray diffraction. Scanning Electron Microscope was utilized to investigate the microstructure of the polycrystalline ferrites. Magnetic properties were discussed by magnetization measurements by using a vibration sample magnetometer.

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AgCl-doped organosilsesquioxane-titania films were prepared by the sol-gel method. Irradiation of the films with a blue laser caused an increase in the absorption in the visible light region; the increased absorption reverted with heating at 100C when the Ti/Si molar ratio was more than 1.5. The cause of the absorption variation which was attributed to the formation and dissociation of Ag nanoparticles was confirmed by XRD. Upon two-beam interference exposure experiment using blue and red lasers, the maximum diffraction efficiency of the AgCl-doped films was about 1.5%, which revealed a potential for an application to future holographic materials.

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Germanate glasses doped with Mn ions were prepared by a melt-quenching method, and the site and luminescence properties of Mn²⁺ ion were investigated. In the germinate glasses containing of Li₂O and ZnO, the octahedrally coordinated Mn²⁺ ions were easily formed, and the red luminescence band due to the ⁴T₁→⁶A₁ transition appeared at the central wavelength of 610 nm. In particular, 75GeO₂-10M₂O-15ZnO glasses (M: Li, Na, and K) showed the strong red luminescence.

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Ag⁺-doped 70B₂O₃-30M₂O, 70B₂O₃-30M'O, and 70B₂O₃-15M₂O-15M'O glasses (M: Li, Na, and K, M': Ca, Sr, and Ba) were prepared by the melt-quenching method, and their fluorescence and excitation spectra were measured. The fluorescence band due to the 4d⁹5s¹→4d¹⁰ transition of Ag⁺ appeared in the UV region. In each glass system, the wavelength of the fluorescence red-shifted with increasing of the basicity of the host glass. Therefore, it was found that Ag⁺ ions were solved into the site of each glass system, and that the crystal field strengthened with increasing of the basicity of the host glass.

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(100-x)Ga₂O3-xZnO-yM_mO_n-0.1MnO powders (M_mO_n: additive, y = 0 or 1) were prepared by a solid-state reaction. Without any additives, 51Ga₂O₃-49ZnO-0.1MnO powder, which included a lot of the gallium-oxygen vacancy pair (V_O, V_Ga), showed the strongest green luminescence due to the ⁴T₁→⁶A₁ transition of Mn²⁺ ions. The intensity of the green luminescence was increased by the addition of oxides with low basicity, which had the ability to form an oxygen vacancy. Therefore, it was found that the green luminescence was closely related with the oxygen vacancies. In this study, 51Ga₂O₃-49ZnO-1B₂O₃-0.1MnO powder showed the strongest green luminescence.

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