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Detailed transmission electron microscopy (TEM) investigations of the degree of delamination, crystallinity, microstructure, interface and surface structure, defects and chemical composition of nanosheets are reported. The effects of the present multiplex synthetic routine including ion exchange, intercalation and exfoliation processes are discussed.

Research describing the chemical valence of cerium ions incorporated in alpha-sialon is presented. In particular the electron energy loss spectra of cerium in different locations in the microstructure is examined.

Critical-current density ([J.sub.c]) is a parameter of primary importance for potential applications of high-temperature copper oxide superconductors. It is limited principally by the breakdown of zero-resistive current due to thermally activated flux flow at high temperatures and high magnetic fields. One promising method to overcome this limitation is to introduce efficient pinning centers into crystals that can suppress the flux flow. A marked increase in [J.sub.c] was observed in [Bi.sub.2][Sr.sub.2][CaCu.sub.2][O.sub.8+Δ (Bi-2212) single crystals doped with a large amount of Pb. By electron microscopy, characteristic microstructures were revealed that probably underlie the observed enhancement in [J.sub.c]: thin (10 to 50 nanometers), platelike domains having a modulation-free structure appeared with spacings of 50 to 100 nanometers along the b axis., High-temperature copper oxide superconductors (HTSCs) exhibit an unusual magnetic field-temperature (H-T) phase diagram that differs from that of conventional superconductors (1, 2). The major reason is the strongly two-dimensional (2D) [...]

Electron diffraction and transmission electron microscope analyses of BaTiO3 thin films on Pt/MgO substrates reveal the absence of other phase formations at the onset of epitaxial growth. An increase in rate of deposition converts the BaTiO3 islands on the Pt surface to a continuous layer, as revealed by atomic force microscopy. Enhancement of film thickness causes a variation in lattice parameters and dielectric properties. The thermodynamic theory accounts for the increase in dielectric constant with film thickness up to a value of 700.

The atomic layer growth of oxide thin films with perovskite-type structure by reactive evaporation was investigated using reflection high-energy electron diffraction. The results showed that the alternate supply of Ba or Sr and Ti on the growing surface allowed atomic layer growth to be achieved. In coevaporation, epitaxial growth was characterized by a unit-cell-by-unit-cell mode, with the surface of each unit cell terminated by a TiO2 layer.

Electrical resistivity, thermoelectric power, Hall coefficient and thermal conductivity have been used to analyze the thermoelectric and transport properties of CeBiPt and the nonmagnetic LaBiPt. It is concluded that CiBiPt is a semimetal with a small carrier concentration, with the mobility heavily depending on the temperature.

High resolution analytical electron microscopy was used to characterize a cubic Si3N4 phase/nanostructure.

Research was conducted to examine the precise structure of multiwalled boron nitride (BN) nanotubes using electron energy loss spectroscopy and high-resolution transmission electron microscopy. The nanotubes were generated from carbon nanotubes via the novel substitution chemical reaction. Results demonstrate that in contrast to the starting carbon nanotubes, which displayed a large number of shells, wide distribution of helicities and poor degree of graphitization, the resultant BN exhibited perfectly straight shapes, remarkable ordering of the graphene-like sheets and limited number of shells.