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Abstract: Two-dimensional, nonlinear and nonhydrostatic field-scale numerical simulations are used to examine the resuspension, dispersal and transport of mud-like sediment caused by the shoaling and breaking of long internal solitary waves on uniform slopes. The patterns of erosion and transport are both examined, in a series of test cases with varying conditions. Shoreward sediment movement is mainly within boluses, while seaward movement is within intermediate nepheloid layers. Several relationships between properties of the suspended sediment and control parameters are determined such as the horizontal extent of the nehpeloid layers, the total mass of resuspended sediment and the point of maximum bed erosion. The numerical results provide a plausible explanation for acoustic backscatter patterns observed during and after the shoaling of internal solitary wavetrains in a natural coastal environment. The results may be useful in the interpretation of some sedimentary structures, and suggest an effective mechanism for offshore dispersal of muddy sediments. [Copyright &y& Elsevier]

Misalignment angles in multifilament Bi2212 tapes have been studied by transport current density (Jc) measurements. Transversal misalignment angles depend on the filaments thickness due to the crystal growth along the Bi2212/silver interface. Therefore, the thinner the filaments, the higher the Jc.A dynamic thermal treatment improves grain alignment inside the tapes due to preferential crystal growth along the thermal gradient direction. Furthermore, melting in high magnetic field reduces the misalignment angle due to magnetic anisotropy effects. Therefore, good transport Jc performances can be expected for thicker multifilament Bi2212 tapes prepared using a combination of the dynamic process and melting in a high magnetic field. [Copyright &y& Elsevier]

Conductors cut from large YBCO and NdBCO single domain crystals, textured by the top seeding technique, are measured in transport current. For YBCO, the magnetic field angular dependence of critical current densities along the ab planes and along the c-axis is measured as a function of temperature. A special accent is put on measurements with a configuration of the field in the ab planes and the current along the c-axis for which vortex pinning is strongly influenced by twin planes. [Copyright &y& Elsevier]

Abstract Electrical properties of Ag films elaborated by Physical Vapor Deposition (PVD) process has been studied before and after corrosion exposure. We have shown that the minimum thickness of silver to resist to sulphurization atmosphere is one micron with an adherent coating. After a sulfurization time of 600 min, an electrical resistivity increase of only 10% is obtained for a film with 2 μm in thickness. This value is about 20% higher than the electrical resistivity of pure silver bulk material. For industrial applications of silver coatings, these results are relevant and demonstrate that PVD is an interesting process compared to the electrochemical ones for which silver thicknesses close to 5 μm are necessarily coated. Highlights • The minimum thickness of silver to resist to sulphurization atmosphere is one micron. The electrical resistivity increase is lower than 10% with an adherent coating behaviour. • After a sulfurization time of 600 min, the electrical resistivity remains lower than 0.022 μΩ m. • PVD process is as interesting and relevant as electrochemical ones for silver coatings. [ABSTRACT FROM AUTHOR]

A superconducting fault current limiter using YBCO single domains requires long elements cut along the ab-planes or along the c-axis. These elements have to be assembled in series in order to produce a limited fault current after the quench to the resistive state under the network voltage. The superconductor total length is much smaller with c-axis elements because their high resistivity after transition contributes to a very high electric field during the current limitation. The critical current density has to be decreased in order to be sure that the Joule effect related to the limiting current does not increase too much the material temperature before its interruption by a current breaker. The inhomogeneously oxygenated YBCO elements limit the current even if the only surface layer is superconducting and produce an electric field up to 5000 V/m. A homogeneous oxygenation without macrocrack is obtained when the thickness along the ab-planes is thin. Several elements have been tested by applying a 20 ms duration fault current in a liquid nitrogen bath at T=77 K and above. [Copyright &y& Elsevier]