Damage in textile composites is closely connected with the internal micro-and meso-geometry of the reinforcement, and reveals features, which are not present in the damage processes in classical laminates. This paper proposes a test sequence intended to characterise damage in textile composites -its initiation and development different scale levels: (1) Tensile tests on samples cut in characteristic directions of the textile reinforcement (machine, cross and bias), accompanied with acoustic emission (AE) registration and full-field strain measurement on the surface. The test produces stress-strain diagrams and identifies characteristic strain levels for post-mortem investigation: just after first damage e 1 ; well-developed damage e 2 ; just before the final fracture of the sample e 3 . Full-field strain measurement highlights the relation between strain concentrations (linked with the damage initiation) and the reinforcement structure. (2) Samples loaded up to e 1. . .3 are examined with CT and X-ray. This reveals the damage pattern and allows quantitative characterising of the damage development.(3) Optical and SEM examination of cross-sections through the damage sites, determined with X-ray, identifies local damage modes. The same strain levels are further used for setting up fatigue tests. The experimental protocol is applied for triaxial braided and quasi-UD composites.

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We report superconducting resistive transition characteristics for array͑s͒ of coupled 4 Å single wall carbon nanotubes embedded in aluminophosphate-five zeolite. The transition was observed to initiate at 15 K with a slow resistance decrease switching to a sharp, order of magnitude drop at ϳ7.5 K. The latter exhibits anisotropic magnetic field dependence, and the differential resistance versus current ͑voltage͒ measurements show a rich variety of details that are consistent with the establishment of coherence, in stages, as the temperature is lowered below 15 K. In particular, the resistance drop that starts at 7.5 K exhibits attributes that are consistent with the manifestations of a Berezinskii-Kosterlitz-Thouless transition that establishes quasi-long-range order in the plane transverse to the c axis of the aligned nanotubes.

On-chip integrated mode-division multiplexing (MDM) is an emerging technique for large-capacity data communications. In the past few years, while several configurations have been developed to realize on-chip MDM circuits, their practical applications are significantly hindered by the large footprint and inter-mode cross talk. Most importantly, the high-speed MDM signal transmission in an arbitrarily routed circuit is still absent. Herein, we demonstrate the MDM circuits based on digitized meta-structures which have extremely compact footprints. 112 Gbit/s signals encoded on each mode are arbitrarily routed through the circuits consisting of many sharp bends and compact crossings with a bit error rate under forward error correction limit. This will significantly improve the integration density and benefit various on-chip multimode optical systems.