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Previous high-resolution electron microscopy (HREM) observations of the carbon nanotubes have led to a "Russian doll" structural model that is based on hollow concentric cylinders capped at both ends. The structures of the carbon nanotubes and particles were characterized here by bulk physical and chemical property measurements. The individual nanostructure is as compressible as graphite in the c axis, and such nanostructures can be intercalated with potassium and rubidium, leading to a saturation composition of "MC(8)." These results are counter to expectations that are based on a Russian doll structure. HREM after intercalation with potassium and deintercalation indicates that individual nanoparticles are a "paper-mache" of smaller graphite layers. Direct current magnetization and electron spin resonance measurements indicate that the electronic properties of the nanostructures are distinctly different from those of graphite. Although the nanostructures have distinct morphologies and electronic properties, they are highly defective and have a local structure similar to turbostratic graphite.

Epitaxial ferroelectric SrRuO3/Pb(Zr0.52Ti0.48)O3/SrRuO3 heterostructures have been fabricated employing isotropic metallic oxide electrodes on (100) SrTiO3 and (100) Si with an yttria stabilized zirconia buffer layer. The structures have been grown in situ by 90° off-axis sputtering, which allows the growth of uniform stoichiometric films over large areas with excellent step coverage. X-ray diffraction, Rutherford backscattering spectroscopy, and cross-sectional transmission electron microscopy reveal high crystalline quality and coherent interfaces. They exhibit superior fatigue characteristics over those made with metal electrodes, showing little degradation over 1010 cycles, with a large remnant polarization.

Sr2Ir04 and Sr2Ru04 are both K,NiF4-structure oxides. Sr2Ir04 is a weakly ferromagnetic insulator and Sr2Ru04 a paramagnetic metal. The Sr2Irl Ru"04 solid solution displays surprising physical properties. On the substitution of Ru to Sr2Ir04, the Ru first exhibits its expected S =1 local magnetic moment, but at a critical Ru concentration of x =-0.7 the local moment disappears, the apparent density of states at E+ increases, and an insulator-to-metal transition occurs. These changes in physical properties are accompanied by a change in the crystallographic cell parameters.

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