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Present a study which investigated the intermediate phases produced in the growth of Bi[sub2]Sr[sub2]Ca[sub2]Cu[sub3]O[sub10+δ]. Details of the experimental techniques used; Factors which dominate the initial X-ray spectrum of the starting pellet.

Examines several aspects of decomposition of BiPb(2223) under a variety of conditions. X-ray data for the starting powder illustrating the identification of all of the major peaks as BiPb peaks; Discussion on the decomposition of BiPb(2223).

Presents information on a study which investigated crystallization of a bismuth compound as a function of the partial pressure oxygen using in situ high temperature x-ray measurements, in order to determine the phases that form and the kinetics of growth. Methods; Results; Discussion.

Studies the strain tolerance of doctor blade tapes of a high-temperature superconductor to determine the suitability of these materials for magnet conductors. Method of the study; Results and discussion; Conclusion.

Discusses a study which examined strain tolerance of Bi[sub2]Sr[sub2]Ca[sub1]Cu[sub2]O[sub8-8]/Ag composites at fields up to 20 T and bending strains up to 2.6% in order to determine the factors that control the critical current density. Idea in using silver to provide regions of plastic flow; Conductors that are easy to fabricate; Role of grain boundaries and silver barriers in the weak-link problem.

Presents a study that utilized transport currents in a cross strip superconducting-normal metal-superconducting (SNS) Josephson junction to bias the current-voltage characteristics of the junction. Features of SNS junctions; Approximation of the current-voltage characteristics of SNS junctions.

Measurements of 10 GHz microwave surface resistance, R[sub s], of dense MgB[sub 2] wire and pellet are reported. Significant improvements are observed in the wire with reduction of porosity. The data lie substantially above the theoretical estimates for a pure Bardeen-Cooper-Schrieffer s-wave superconductor. However, the R[sub s] (20 K) of the wire is an order of magnitude lower than that of polycrystal YBa[sub 2]Cu[sub 3]O[sub 6.95] and matches with single-crystal YBa[sub 2]Cu[sub 3]O[sub 6.95]. The results show promise for the use of MgB[sub 2] in microwave applications. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A pressure cell has been designed to study the magnetostrictive properties of a material as a function of both pressure and magnetic field. For changes in length on the order of 2000 ppm, it is necessary to have a substantial compliance in the pressure cell to retain a constant stress over the length of travel. [ABSTRACT FROM AUTHOR]

The conversion of long slender filaments of Bi-based high-temperature superconductors from the amorphous to the crystalline phase has been studied in order to determine the suitability of these fibers for use in a multifilamentary magnet conductor. For very fine filaments, coarsening may be a problem, so special emphasis was placed on the optimum values of time and temperature used for recrystallization. Amorphous fibers approximately 1 μm in diameter can be crystallized to form granular filaments about 0.2 μm thick (in the c direction) and 3 to 4 μm wide. The c axis generally grows perpendicular to the long axis of the fiber. [ABSTRACT FROM AUTHOR]

Procedures have been developed for the preparation of long slender fibers of Bi-Sr-Ca-Cu-O using a gas jet to shape and freeze the material. The fibers emerge in amorphous form and are converted to the Bi[sub 2]Sr[sub 2]Ca[sub 1]Ca[sub 2]O[sub x] phase by subsequent heat treatment. Magnetization and scanning electron microscopy studies show the material to be a very fine grained bulk superconductor with intragranular critical currents of 7 × l0[sup 6] A/cm² at 5 K and 1.8 T. [ABSTRACT FROM AUTHOR]

A study of the motion of quantized vortices in cylindrical superconducting thin films was undertaken to determine the feasibility of constructing a magnetic shield in which the trapped transverse magnetic flux could be systematically swept out. The idea is to induce vortex-antivortex annihilation along one side of the cylinder under the influence of the Lorentz force using a transport current parallel to the axis of the cylinder. It is found that for a granular aluminum film approximately 1500 Å thick, there is a narrow temperature window near the critical temperature in which the vortices and antivortices can indeed be swept to one side and the internal field significantly reduced. [ABSTRACT FROM AUTHOR]