[structure: see text] New dicyanovinyl-substituted 1-(alkyl)aryl-2-(2'-thienyl)pyrroles 2 were synthesized and characterized. The solvatochromic behavior of the synthesized compounds was investigated. All the derivatives showed reversible oxidation and reduction on the CV time scale. The hyperpolarizabilities (beta) of compounds 2 were measured using hyper-Rayleigh scattering. The results are among the highest beta values reported for donor-acceptor-substituted thienylpyrroles.

The aim of this paper is to present an automatic yarn hairiness parameterization method based on optical sensors. Hairiness measurements are performed using a coherent signal processing technique for higher resolution. Using this optical technique together with electronic instrumentation and custom developed software, it is possible to quantify all traditional hairiness parameters (i.e. hairiness (H), its coefficient of variation (CVH) and standard deviation (sH)) used in the textile industry, as well as determine several others, such as mean deviation coefficient (U), deviation rate (DR) and its integral (IDR).The overall goal of the current project is to develop an integrated automatic yarn system characterization: evenness analysis determination using capacitive sensors, hairiness analysis using coherent optics technique and finally, image processing for yarn production characteristics.

The piezoresistive response of epoxy/vapor-grown carbon nanofiber composites prepared by four different dispersion methods achieving different dispersion levels has been investigated. The composite response was measured as a function of carbon nanofiber loading for the different dispersion methods. Strain sensing by variation of the electrical resistance was tested through four-point bending experiments, and the dependence of the gauge factor as a function of the deformation and velocity of deformation was calculated as well as the stability of the electrical response. The composites demonstrated an appropriate response for being used as a piezoresistive sensor. Specific findings were that the intrinsic piezoresistive response was only effective around the percolation threshold and that good cluster dispersion was more appropriate for a good piezoresistive response than a uniform dispersion of individual nanofibers. The application limits of these materials for sensor applications are also addressed.

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In this work, epoxy composites reinforced with vapor‐grown carbon nanofibers were prepared by a simple dispersion method and studied in order to identify the main conduction mechanism. The samples show high electrical conductivity values. The results indicate that a good cluster distribution seems to be more important than the fillers dispersion in order to achieve high conductivity values. Interparticle tunneling has been identified as the main mechanism responsible for the observed behavior.