Solution impregnations, pulltrusion and film stacking are widely used methods to prepare thermoplastic composite materials. Extruders are used to melt the polymer and to incorporate fibers into the polymer in order to modify physical properties. In this article, the compounding of colloidal silica nanoparticles filled polyamide-6 (PA-6) is achieved using a twin-screw extruder, which has a significant market share due to its low cost and easy maintenance. The experiments were performed at 250 rpm and the bulk throughput was 6 kg h À1 with a pump pressure of 30 bars. The composites were characterized with nuclear magnetic resonance (NMR), wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). As determined by WAXD, the PA-6 showed higher amounts of c-phase when compared to other synthesis methods such as in situ polymerization. TEM pictures showed that the silica particles aggregated nevertheless, upon addition of 14% (w/w) silica the E-modulus increased from 2.7 to 3.9 GPa indicating that an effective mechanical coupling with the polymer was achieved. The behavior, illustrated with dynamic mechanical analysis (DMA) curves, indicated that in general when a filled system is compared to unfilled material, the values of the moduli (E 0 and E 00 ) increased and tan d decreased. Determination of molecular mass distribution of the samples by means of size exclusion chromatography (SEC) coupled to a refractive index (RI), viscosity (DV) and light scattering (LS) detector revealed that the addition of silica did not decrease the average molecular weight of the polymer matrix, which is of importance for composite applications.

A fundamental problem for disabled or elderly people is to manage their homes while carrying out an almost normal life, which implies using and interacting with a number of home devices. Recent studies in smart homes have proposed methods to use a laser pointer for interacting with home devices, which represents a more user-friendly and less expensive home device control environment. However, detecting the laser spot on the original non-filtered images, using standard and non-expensive cameras, and considering real home environments with varying conditions, is currently an open problem.This paper proposes a hybrid technique, where a classic technique used in image detection processes, such as Template Matching, has been combined with a Fuzzy Rule

Simple engineering correlations and a linear jet breakup model are used to estimate the orders of magnitude of characteristic times of the various processes involved in the supercritical antisolvent method (SAS) of particle formation. The characteristic times of jet breakup, mass transfer, and nucleation are studied under typical conditions of pressure and temperature in the two-phase regime for a mixture of carbon dioxide and ethanol. The results of the calculations suggest that the jet breakup phenomenon is much faster than the mass transfer process. This difference in the characteristic times indicates that only a small amount of the supercritical fluid has had time to diffuse into the liquid jet stream by the time the breakup takes place. The characteristic nucleation times can vary appreciably with process conditions (e.g., supersaturation) and the specific properties of the mixture where precipitation occurs (e.g., liquid−solid interfacial tension). On the basis of the present calculations, two different regimes can be anticipated:  a diffusion-limited regime leading to a precipitation front and a nucleation-limited, well-mixed regime.

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