A micromechanics model for 3D elasticity and failure of woven-fibre composite materials

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The effect of ageing on the damage events in woven-fibre composite materials under different loading conditions

International audienc

Prediction of the elastic behaviour of hybrid and non-hybrid woven composites

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A micromechanics model for 3D elasticity and failure of woven-fibre composite materials

International audienceAn analytical model called MESOTEX (MEchanical Simulation Of TEXtile) is proposed in this paper with the objective of predicting 3D elastic and failure properties of several woven fibre composite materials. Based on the use of the classical thin laminate theory to the woven structure, the mesotex model is used to analyze plain-weave, satin-weave and twill-weave composites and their hybrid equivalents. Stiffness properties are computed and compared with test data and with the results of other micromechanical models. This correlation is followed by a parametric study in which the effect of strand waviness on the elastic properties is discussed for different woven-fibre composites. Moreover, this analytical model is extended in order to predict failure strength under tensile load in woven-fibre composite materials with a point-wise stiffness reduction technique

Unsupervised clustering for building a learning database of acoustic emission signals to identify damage mechanisms in unidirectional laminates

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Dissimilarity-based time–frequency distributions as features for epileptic EEG signal classification

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Recent applications of carbon-based nanomaterials in analytical chemistry: Critical review

The objective of this review is to provide a broad overview of the advantages and limitations of carbon-based nanomaterials with respect to analytical chemistry. Aiming to illustrate the impact of nanomaterials on the development of novel analytical applications, developments reported in the 2005-2010 period have been included and divided into sample preparation, separation, and detection. Within each section, fullerenes, carbon nanotubes, graphene, and composite materials will be addressed specifically. Although only briefly discussed, included is a section highlighting nanomaterials with interesting catalytic properties that can be used in the design of future devices for analytical chemistry.Fil: Scida, Karen. University of Texas; Estados UnidosFil: Stege, Patricia Wanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Haby, Gabrielle. University of Texas; Estados UnidosFil: Messina, Germán Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: García, Carlos D.. University of Texas; Estados Unido

Predicting mechanical properties of multiscale composites

The effect of carbon nanotube (CNT) integration in polymer matrixes (two-phase) and fibre reinforced composites (three-phase) was studied. Simulations for CNT/polymer composites (nanocomposites) and CNT/fibre/polymer composites (multiscale) were carried out by combining micromechanical theories applied to nanoscale and woven fibre micromechanic theories. The mechanical properties (Young's modulus, Poisson's ratio and shear modulus) of a multiscale composite were predicted. The relationships between the mechanical properties of nano- and multiscale composite systems for various CNT aspect ratios were studied. A comparison was made between a multiscale system with CNTs infused throughout and one with nanotubes excluded from the fabric tows. The mechanical properties of the composites improved with increased CNT loading. The influence of CNT aspect ratio on the mechanical properties was more pronounced in the nanocomposites than in the multiscale composites. Composites with CNTs in the fibre strands generated more desirable mechanical properties than those with no CNTs in the fibre strands.open0

DNA Detection Using Origami Paper Analytical Devices

We demonstrate the hybridization-induced fluorescence detection of DNA on an origami-based paper analytical device (<i>o</i>PAD). The paper substrate was patterned by wax printing and controlled heating to construct hydrophilic channels and hydrophobic barriers in a three-dimensional fashion. A competitive assay was developed where the analyte, a single-stranded DNA (ssDNA), and a quencher-labeled ssDNA competed for hybridization with a fluorophore-labeled ssDNA probe. Upon hybridization of the analyte with the fluorophore-labeled ssDNA, a linear response of fluorescence vs analyte concentration was observed with an extrapolated limit of detection <5 nM and a sensitivity relative standard deviation as low as 3%. The <i>o</i>PAD setup was also tested against OR/AND logic gates, proving to be successful in both detection systems