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Fabrication of high Tc ceramic superconductors by an oxide melting method in place of a conventional sintering method has been attempted. Using three different processes, i.e., melt drawing, melt spinning, or preform-wire melting, it is demonstrated that the Ba2YCu3O7-δ type superconductors can successfully be fabricated into a desired geometry such as wire and ribbon. Tc’s for R=0 were about 92 K. The density of the melt-processed compound was measured to be as high as 6.2 g/cm3, or ∼98% of the theoretical density 6.3 g/cm3 as compared to the value of 80–85% density for sintered samples. The increased density is likely to be responsible for the noted improvements in fracture resistance and in the Jc value of the melt-processed compound. [ABSTRACT FROM AUTHOR]

Describes the levitation of a magnet over a Type II superconductor. Superconductors used in the study; Mathematical models of the magnetic sphere and superconducting plane; Discussion on the results of the study.

We show that the superconducting YBa2Cu3O7 phase is highly sensitive to water and water vapor. This is probably due to the presence of nonequilibrium Cu3+ ions in this compound. In particular, the YBa2Cu3O7 phase decomposes in water to CuO, Ba(OH)2 and Y2BaCuO5 and evolves oxygen. Samples with a reduced oxygen content, e.g., YBa2Cu3O6.0, also decompose in an aqueous ambient. The superconductivity of YBa2Cu3O7 samples is greatly degraded by the interaction with water and humid air. This effect should not preclude practical application of these materials since it should be possible to protect them with coatings of metal, glass, or plastic. [ABSTRACT FROM AUTHOR]

The development of an optically transparent yet electrically conductive material made with a composite structure having preferentially arranged conductive paths is described. The medium contains many vertically aligned but laterally isolated chains of ferromagnetic spheres dispersed in a sheet of transparent polymer. The sheet material transmits more than 90 percent of the incident light and is highly conductive only in the thickness direction. When suitably modified, the material exhibits on-off electrical switchability at a certain threshold pressure. These characteristics confer potential usefulness for visual communication devices such as write pads or touch-sensitive screens.

This report describes an inguinal lymphocele following thighplasty. Lymphoceles are caused by a continuing leak of lymph from transected lymphatic ducts. They usually appear several weeks following surgery and can be identified by characteristic physical findings and laboratory tests present in predisposing clinical situations. The size and location of a lymphocele will determine the treatment required. In this particular case, the infected lymphocele was incised and drained and it healed secondarily.