There is a high content of calcium carbonate in mussel and oyster shells, which can be used in the formulation of medicine, in construction or as filler in polymer materials. This work has as its main objective to obtain calcium carbonate from mussel and oyster shells and used as filler in polypropylene compared their properties with polypropylene and commercial calcium carbonate composites. The shellfish was milling and heated at 500 °C for 2 hours. The powder obtained from shellfish were characterized by scanning electron microscopy (SEM), X-ray fluorescence, particle size distribution and abrasiveness and compared with commercial CaCO 3 and mixed with polypropylene. The thermal and mechanical properties of polypropylene with CaCO 3 obtained from oyster and mussel shells and with commercial CaCO 3 were analysed. The results showed that CaCO 3 can be obtained from oyster and mussel shell and is technically possible to replace the commercial CaCO 3 for that obtained from the shells of shellfish in polypropylene composites.

The 3-year prospective study using sensitive detection methods, reliable confirmation, and feedback from clinicians showed that CT has an extraordinarily high prevalence in Brazil, in fact the highest ever reported in the world. Although the long-term efficacy of treatment of CT has not been well documented, in view of the availability of reliable diagnostics, confirmation and monitoring, functional logistics, and networking for screening, the insidious nature of the sequelae and the very high prevalence of the disease, neonatal screening for CT should be considered an alternative to no screening at all.

Abstract. The increasing usage of new technologies implies changes for personality research. First, human behavior becomes measurable by digital data, and second, digital manifestations to some extent replace conventional behavior in the analog world. This offers the opportunity to investigate personality traits by means of digital footprints. In this context, the investigation of the personality trait sensation seeking attracted our attention as objective behavioral correlates have been missing so far. By collecting behavioral markers (e.g., communication or app usage) via Android smartphones, we examined whether self-reported sensation seeking scores can be reliably predicted. Overall, 260 subjects participated in our 30-day real-life data logging study. Using a machine learning approach, we evaluated cross-validated model fit based on how accurate sensation seeking scores can be predicted in unseen samples. Our findings highlight the potential of mobile sensing techniques in personality research and show exemplarily how prediction approaches can help to foster an increased understanding of human behavior.

In this work, the effect of TiO 2 addition over morphological and ultraviolet (UV) blocking properties of poly(lactic acid) (PLA) and poly(E-caprolactone) (PCL) blends was investigated. The micrographs showed a partially co-continuous structure in the PLA/PCL blend with 42/58 (wt %/wt %) and the TiO 2 nanoparticles addition leads to a structural phase inversion, i.e., continuous PCL and partially continuous PLA with a dispersed portion. TiO 2 nanoparticles were observed to be preferably localized at the interface of the two phases due to kinetic effects (large difference between the melting temperatures) and nanoparticle geometry (low aspect ratios). An adhesion improvement between the phases and morphological stability were observed with the addition of TiO 2 nanoparticles. This behavior indicates that the nanoparticles can act as compatibilizers due to their localization at the interface between the two phases. The UV light absorption and transmission percolation threshold occurred with 1.5% TiO 2 in the 42PLA/ 52PCL blend.

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Using the model of a cylinder-type heat source, the power loss owing to heat conduction in laser cutting and welding of metals is calculated analytically. The case of laser cutting is described by taking into account the influence of the generated cutting kerf using numerical calculations. Both the analytical and the numerical solution for the power loss deposited into the material are well described by approximative formulae. The theoretically predicted power loss into the cut workpiece is confirmed by measurements of the temperature rise within the metal sheet in laser cutting experiments.

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In this work, the relations between fracture surface roughness in mode I and the content of different carbon nanoparticles, graphene nanoplatelets (GNP) and carbon nanotubes (CNT) were systematically investigated. A block copolymer (BC) was also used to aid the dispersion process considering its role on fracture toughness. Both KIc and GIc were found to increase significantly with the addition of a BC along with carbon nanoparticles. Roughness measurements showed that the value of surface roughness (Ra) does not depend on the toughness, and decreases as the precrack distance increases. In the system with the greatest amount of graphene (0.5 wt%), the agglomerates impaired the material's tenacity and crack deflection with GNP delamination as the fracture mechanism. As for the CNT/epoxy nanocomposites with the BC, strong adhesion between matrix and nanotubes prevented debonding, so the CNTs break, rather than pulling out, after crack bridging, the so called sliding‐fracture mode failure. POLYM. COMPOS., 39:E2262–E2273, 2018. © 2017 Society of Plastics Engineers