The fabrication of P3HT nanopatterns (lamellae and fibres) within a few minutes, in standard laboratory\ud conditions (i.e., at room temperature and in air) and over areas as large as cm2, is reported. The\ud nanostructures are prepared using a wet-processing method. A satisfactory control over the pattern\ud topology (lamellae, hierarchically connected and parallel fibres, entangled but disconnected and quasiparallel\ud fibres, randomly oriented fibres) is obtained by simply changing one process parameter. UV-vis\ud spectroscopy and X-ray diffraction analyses carried out over the so-fabricated structures evidence a very\ud high degree of supramolecular organization of the polymeric chains. Such a degree of order is similar or\ud even better than that of P3HT samples treated with thermal or solvent annealing procedures

OBREC is the acronym that stands for Overtopping Breakwater for Energy Conversion. It is a multifunctional device aimed to produce energy from the waves, while keeping the harbour area protected from flooding. In this paper, the inclusions of a berm to reduce wave reflection, the shape of the sloping plate to maximise wave overtopping and the reservoir width and the crown wall shape to maximise wave energy capture while keeping the harbour safety were analysed to optimize the hydraulic and structural performances of the device. Several configurations were numerically investigated by means of a 2DV RANS-VOF code to extend the results already obtained during previous experimental campaigns. The wave reflection coefficient, the average wave overtopping flows and the wave loadings along the structure are computed, compared with existing formulae and discussed with reference to the OBREC prototype installed in the Port of Naples.

This contribution proposes a systematic analysis of the overtopping process at dikes, focused on the statistical description of the extreme flow characteristics across the dike crest. The specific objective of the analysis is the investigation of structures subjected to high run-up levels and low freeboards, under severe or extreme conditions that are likely to occur in the future due to climate change. The adopted methodology is based on the collection of new experimental and numerical tests of wave overtopping at smooth dikes at various crest levels. The reliability of the new data is checked in terms of average overtopping discharge and wave reflection coefficient, against consolidated predicting methods from the literature. An update and refitting of the existing formulae for the prediction of the extreme flow depths and velocities at the dike off-shore edge is proposed based on the experimental and numerical outcomes. The dynamics of the overtopping flow propagation along the dike crest under breaking and non-breaking waves, in emerged and submerged conditions, is investigated. Guidelines to update the state-of-the-art formulae for a more cautious estimation of the water depths and the velocities of propagation of the flow in the landward area are provided.

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