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In this study, Ba0.6Sr0.4Ti1-xMnxO3 ceramics were fabricated by a novel ball milling technique followed by spin-coating to produce thin-film resistive memories. Measurements were made using field emission scanning electron microscopes, atomic force microscopes, X-ray diffractometers, and precision power meters to observe, analyze, and calculate surface microstructures, roughness, crystalline phases, half-height widths, and memory characteristics. Firstly, the effect of different sintering methods with different substitution ratios of Mn4+ for Ti4+ was studied. The surface microstructural changes of the films prepared by the one-time sintering method were compared with those of the solid-state reaction method, and the effects of substituting a small amount of Ti4+ with Mn4+ on the physical properties were analyzed. Finally, the optimal parameters obtained in the first part of the experiment were used for the fabrication of the thin-film resistive memory devices. The voltage and current characteristics, continuous operation times, conduction mechanisms, activation energies, and hopping distances of two types of thin-film resistive memory devices, BST and BSTM, were measured and studied under different compliance currents.

In 1995, a combined ocean-bottom-seismometric (OBS) and multichannel seismic (MCS) survey with strong air-gun shots was carried out in the southernmost Ryukyu subduction zone. A crustal velocity structure constructed from the layer-stripping Monte Carlo inversion of three OBS/MCS profiles and the associated density models inverted from gravity data in the SW end of the Ryukyu arc-trench system are presented. Parallel to the arc in the southernmost Ryukyu subduction system, the OBS/MCS profiles show sedimentary layers of the Hoping, Nanao and East-Nanao forearc basins from west to east, warping of the arc basement and buckling of the subducted slab beneath the Hoping basement rise. The arc-parallel variation of the crustal structure may result from increasing lateral compression westward due to oblique subduction of the Philippine Sea plate and collision with the Luzon arc near the northwestern edge of the forearc region. Northward subduction and arc-parallel compression of the slab also have generated thrust faulting along the subduction interface and strike-slip faulting within the subducted slab, respectively. On 2002 March 31, an earthquake with a moment magnitude of 6.84 was induced by buckling of the subducted slab and strongly affected cities within an epicentral distance of 100 km. The velocity-interface models, the density models and the focal mechanisms presented in this paper therefore suggest that earthquakes induced by slab buckling or arc-parallel compression have been stronger but less frequent than those generated by northward subduction in the Ryukyu seismogenic zone off Taiwan. [ABSTRACT FROM AUTHOR]