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An overview on metal ions detection in water exploiting polymer optical fiber (POF) sensors is presented. A simple and highly sensitive plasmonic sensor in POFs has been functionalized by different specific self-assembled monolayer (SAM) receptors to achieve the specific detection of several metal ions in water. In particular, the detection of uranyl, copper(II), and iron(III) ions is reported here. The developed optical fiber sensors have been demonstrated to be effective for determining these metal ions in water solutions in µM ranges, even lower in the case of uranyl ion (tens of nM).

In this work, we present a chemical extrinsic optical fiber sensor, based on a novel micro-pattern of silver nanoparticles, produced by InkJet printing on a polyethylene terephthalate (PET) substrate, covered by a molecularly imprinted polymer (MIP) film. The optical-chemical sensor chip is monitored via two plastic optical fibers (POFs) connected with a light source and a spectrometer. In particular, the pattern is formed by parallel lines arranged in orthogonal position with respect to the direction of the input light. As a proof of concept, we have deposited on the sensor surface an MIP receptor layer specific for furfural (2-FAL). The preliminary experimental results have shown a limit of detection (LOD) relative to 2-FAL equal to 0.05 ppm, demonstrating the goodness and feasibility in biochemical applications of the proposed sensing approach.

L’Autorizzazione Integrata Ambientale (AIA) è il provvedimento che autorizza l’esercizio di un impianto o parte di esso, in cui si svolgono attività che potrebbero causare significativi impatti ambientali. Con l’AIA le imprese possono uniformarsi ai principi di IPPC che sta per Integrated Pollution Prevention and Control, individuando soluzioni tecniche, impiantistiche ed economiche, per una corretta gestione delle possibili forme di inquinamento. Per raggiungere elevati livelli di protezione dell’ambiente bisogna adottare le Migliori Tecniche Disponibili, in inglese Best Available Technology (BAT). Ad oggi in Italia non è ancora presente un metodo di studio delle migliori tecnologie disponibili, ma una diversa situazione si ha nel Regno Unito dove viene il software H1. Lo scopo del presente lavoro è individuare una metodologia di studio delle BAT per un impianto di trattamento della Frazione Organica dei Rifiuti Solidi Urbani (FORSU) e scarti ligneo-cellulosici per la produzione di biometano situato in Italia, applicando per lo stesso il software inglese.

We are living in the age of the wide internet network, where we first connected contents, then people and now objects. Today, objects and people are constantly entering data into the large network. This is marking two new interesting lines of research: (a) turning "big data" into increasingly useful information; (b) ensuring a "secure" network to protect "sensitive" data. Both lines of research, however, seem to forget a key aspect in this increasingly "unstable" world: the position of the person. Any "secure" computer system and any creation act required to transform data into information, in fact, will always be carried out by people. Therefore, the question we are asking ourselves in this short study is: Is the new focus of the stain and network system the centrality of a person?

For the detection of chemical agents in different environments, the combination of plastic optical fibers (POFs) and molecularly imprinted polymers (MIPs) receptors has been tested as a way to obtain low cost, highly selective and sensitive optical chemical sensors based on plasmonic resonance. In this work, a novel type of optical chemical sensor able to detect the binding reactions occurring between the MIP and analyte has been designed, fabricated and applied for the selective detection of dibenzyl disulfide (DBDS) in transformer oil. This analyte is important in the control of transformer oil, since it is responsible for the corrosive properties of the oil. The new optical sensor platform is based on two plastic optical fibers that work as segmented waveguides coupled through a polymer molecularly imprinted for the analyte. The prepolymeric MIP solution was deposited by drop coating in a trench milled between the two fibers. The experimental results indicated that this new sensor can be useful for the determination of DBDS in transformer oil and it paves the way to a new approach in the optical fiber sensors for MIPs.

Optimization of planar waveguides for fluorescence biosensing is presented in this paper. In particular, the authors show that optical (refractive index) and geometrical parameters have a strong influence on the efficiency of excitation and collection of fluorescent signals. Numerical analyses show that a single-mode slab waveguide, operating at its fundamental transverse magnetic mode and near its cutoff point, results in an efficient fluorescence excitation when employed as evanescent wave biosensor. A high-refractive index contrast is demonstrated to be the key parameter for an efficient fluorescence collection. Other geometries that are an alternative to the classical slab waveguide may result in an improvement of the fluorescence excitation and collection efficiencies.