Monoclinic distortion, polarization rotation and piezoelectricity in the ferroelectric NaBiTiO.

The relationship between crystal structure and physical properties in the ferroelectric NaBiTiO (NBT) has been of interest for the last two decades. Originally, the average structure was held to be of rhombohedral (3) symmetry with a fixed polarization direction. This has undergone a series of revisions, however, based on high-resolution X-ray diffraction, total neutron scattering, and optical and electron microscopy.

Unexpectedly high piezoelectricity of Sm-doped lead zirconate titanate in the Curie point region.

Large piezoelectric coefficients in polycrystalline lead zirconate titanate (PZT) are traditionally achieved through compositional design using a combination of chemical substitution with a donor dopant and adjustment of the zirconium to titanium compositional ratio to meet the morphotropic phase boundary (MPB). In this work, a different route to large piezoelectricity is demonstrated. Results reveal unexpectedly high piezoelectric coefficients at elevated temperatures and compositions far from the MPB.

Topology and temperature dependence of the diffuse X-ray scattering in NaBiTiO ferroelectric single crystals.

The results of high-resolution measurements of the diffuse X-ray scattering produced by a perovskite-based NaBiTiO ferroelectric single crystal between 40 and 620 K are reported. The study was designed as an attempt to resolve numerous controversies regarding the average structure of NaBiTiO, such as the mechanism of the phase transitions between the tetragonal, 4, and rhombohedral | monoclinic, 3 | , space groups and the correlation between structural changes and macroscopic physical properties. The starting point was to search for any transformations of structural disorder in the temperature range of thermal depoling (420-480 K), where the average structure is known to remain unchanged.

An investigation of Zr doping in NaBiTi2O6 perovskite by direct hydrothermal synthesis.

The direct crystallisation of perovskites NaBi(Ti(1-x)Zrx)(2)O(6) with x = 0, 0.01, 0.05 and 0.

Assessment of copper corrosion from frameless copper IUDs after long-term in utero residence.

Objective: To assess the site-specific corrosive behavior of the frameless intrauterine device (IUD) following long-term exposure to the uterine environment.

Study Design: A qualitative and morphological study using X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Results: Three GyneFix® IUDs that were in site up to 150 months were examined.