An alternative for the reutilization of polystyrene waste containers consisting in creating a hybrid material made of SiO2nanoparticles embedded in a matrix of recycled polystyrene (PSR) has been developed. Recycled polystyrene functionalized (PSRF) was used to influence the morphological and antifog properties by the sol-gel synthesis of nanohybrid silica. To this end, silica nanoparticles were produced from alkoxide precursors in the presence of recycled polystyrene. The functionalization of this polymeric matrix was with the purpose of uniting in situ carboxyl and silanol groups during the sol-gel process. In this way, opaque or transparent solid substrates can be obtained, with each of these endowed with optical conditions that depend on the amount of reactants employed to prepare each nanohybrid specimen. The nanohybrids were labelled as SiO2/PSR (HPSR) and SiO2/PSRF (HPSRF) and their properties were then compared to those of commercial polystyrene (PS). All the prepared samples were used for coating glass substrates. The hydrophobicity of the resultant coatings was determined through contact angle measurement. The nanohybrid materials were characterized by FT-IR and1H-NMR techniques. Additionally, TGA and SEM were employed to determine their thermal and textural properties.

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The evaluation of a fuzzy expert positioning servomechanism that was applied for controlling fuel flow in an experimental process is presented. Since the conventional control techniques are not sufficient to implement nonlinear control systems, a successful control technique based on human experience was used. A comparative study was made by both Fuzzy Logic Control (FLC) and Proportional Integral Derivative (PID) control algorithms. Fuzzy Logic and PID controllers were designed in Lab view program. The real-time position control which consists of a DC motor into a servomechanism was implemented by using a digital acquisition device (DAQ). The experimental results show that step response and semicircular trajectory on the position servomechanism for controlling fuel using FLC, had a better performance than those derived from PID control scheme.

The thermal control of loop reactor utilized to run hydrodynamic tests of microbical corrosion, where full control of the temperature is crucial, is presented. Since the accuracy of the temperature is critical along the pipe trajectory for the microbial culture, it must be controlled with an accuracy of  0.5°C, which is achieved by an implemented fuzzy-PID (Proportional Integral and Derivative) control algorithm, capable to provide the accuracy at the temperature range required. The system counts with an especially-designed software to program the desired temperature. Several tests were carried out at different temperatures and water volumes to characterize the rising time and thermal inertia presented by the system. As a result, the performance and power consumption were notability improved.

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