Reduced Order Modeling of Composite Laminates Through Solid-Shell Coupling

<div><p>ABSTRACT: Composite laminates display a complex mechanical behavior due to their microstructure, with a through-thickness variation of the displacement and stress fields that depends on the fiber orientation in each layer. Aiming to develop reduced-order numerical models mimicking the real response of composite structures, we investigated the capability and accuracy of finite element analyses coupling layered shell and solid kinematics. This study represents the first step of a work with the goal of accurately matching stress evolution in regions close to possible impact locations, where delamination is expected to take place, with reduced computational costs. Close to such locations, a 3-D modeling is adopted, whereas in the remainder of the structure, a less computationally demanding shell modeling is chosen. To test the coupled approach, results of numerical simulations are presented for a quasi-statically loaded cross-ply orthotropic plate, either simply supported or fully clamped along its boundary.</p></div

Electrical Double Layer-Induced Ion Surface Accumulation for Ultrasensitive Refractive Index Sensing with Nanostructured Porous Silicon Interferometers

Herein, we provide the first experimental evidence on the use of electrical double layer (EDL)-induced accumulation of charged ions (using both Na⁺ and K⁺ ions in water as the model) onto a negatively charged nanostructured surface (e.g., thermally growth SiO₂)Ion Surface Accumulation, ISAas a means of improving performance of nanostructured porous silicon (PSi) interferometers for optical refractometric applications. Nanostructured PSi interferometers are very promising optical platforms for refractive index sensing due to PSi huge specific surface (hundreds of m² per gram) and low preparation cost (less than $0.01 per 8 in. silicon wafer), though they have shown poor resolution (<i>R</i>) and detection limit (DL) (on the order of 10^–4–10^–5 RIU) compared to other plasmonic and photonic platforms (<i>R</i> and DL on the order of 10^–7–10^–8 RIU). This can be ascribed to both low sensitivity and high noise floor of PSi interferometers when bulk refractive index variation of the solution infiltrating the nanopores either approaches or is below 10^–4 RIU. Electrical double layer-induced ion surface accumulation (EDL-ISA) on oxidized PSi interferometers allows the interferometer output signal (spectral interferogram) to be impressively amplified at bulk refractive index variation below 10^–4 RIU, increasing, in turn, sensitivity up to 2 orders of magnitude and allowing reliable measurement of refractive index variations to be carried out with both DL and R of 10^–7 RIU. This represents a 250-fold-improvement (at least) with respect to the state-of-the-art literature on PSi refractometers and pushes PSi interferometer performance to that of state-of-the-art ultrasensitive photonics/plasmonics refractive index platforms

Shum et al 3D usat genotypes

Microsatellite data previously genotyped by Stefansson et al Heredity (2009) 102, 514–524

Dryad_Rhodopsin_Sebastes_mentella_Peter_Shum_Genbank_KR818563–KR818700

Rhodopsin sequences of North Atlantic Sebastes mentell

Dryad_mtDNA_Sebastes_Peter_Shum_Genbank_KP988027–KP988288

Mitochondrial control region of North Atlantic Sebastes (S. viviparus, S. fasciatus, S. norvegicus, S. mentella

14lociDRYAD

The datafile is in GENEPOP format. It comprises genotype scores for 14 Crassostrea gigas-specific microsatellite loci. Locus names are listed at the beginning of the file under the title line, the first 7 loci are EST linked loci, the last 7 are anonymous loci. The first column under the loci names indicates the 6 population (WONE, WTWO, WTHR, AQON, AQTW, BONE) and their individuals. The genotypes for each individual and loci are in the columns 2 – 15. Missing genotypes are coded as "000". Allele scores for each locus are concatenated into six digits, with the first three letters representing allele "A", and the second three letters representing allele "B"

Cnufar_santer_Genepop

Microsatellites - Genepop format file of C. nufar. Three populations coded as follows: PE-Park Edward, RB-Richards Bay, PR-Park Ryni

Flexible Polydimethyl­siloxane Foams Decorated with Multiwalled Carbon Nanotubes Enable Unprecedented Detection of Ultralow Strain and Pressure Coupled with a Large Working Range

Low-cost piezoresistive strain/pressure sensors with large working range, at the same time able to reliably detect ultralow strain (≤0.1%) and pressure (≤1 Pa), are one of the challenges that have still to be overcome for flexible piezoresistive materials toward personalized health-monitoring applications. In this work, we report on unprecedented, simultaneous detection of ultrasmall strain (0.1%, i.e., 10 μm displacement over 10 mm) and subtle pressure (20 Pa, i.e., a force of only 2 mN over an area of 1 cm²) in compression mode, coupled with a large working range (i.e., up to 60% for strain6 mm in displacementand 50 kPa for pressure) using piezoresistive, flexible three-dimensional (3D) macroporous polydimethyl­siloxane (pPDMS) foams decorated with pristine multiwalled carbon nanotubes (CNTs). pPDMS/CNT foams with pore size up to 500 μm (i.e., twice the size of those of commonly used foams, at least) and porosity of 77%, decorated with a nanostructured surface network of CNTs at densities ranging from 7.5 to 37 mg/cm³ are prepared using a low-cost and scalable process, through replica molding of sacrificial sugar templates and subsequent drop-casting of CNT ink. A thorough characterization shows that piezoresistive properties of the foams can be finely tuned by controlling the CNT density and reach an optimum at a CNT density of 25 mg/cm³, for which a maximum change of the material resistivity (e.g., ρ₀/ρ₅₀ = 4 at 50% strain) is achieved under compression. Further static and dynamic characterization of the pPDMS/CNT foams with 25 mg/cm³ of CNTs highlights that detection limits for strain and pressure are 0.03% (3 μm displacement over 10 mm) and 6 Pa (0.6 mN over an area of 1 cm²), respectively; moreover, good stability and limited hysteresis are apparent by cycling the foams with 255 compression–release cycles over the strain range of 0–60%, at different strain rates up to 10 mm/min. Our results on piezoresistive, flexible pPDMS/CNT foams pave the way toward breakthrough applications for personalized health care, though not limited to these, which have not been fully addressed to date with flexible strain/stress sensors

Saurata_Alleles_Dryad

Microsatellites' allele

Cpuniceus_slinger_Genepop

Microsatellites - Genepop format file of C. puniceus. Three populations coded as follows: PE-Port Edward, PR-Park Rynie, RB-Richards Ba