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Electric vehicles still account for a small share of the total amount of cars on the road. One of the major issues preventing a larger uptake is their higher upfront cost compared to petrol cars. We aim to address this issue by investigating a module-based product-family approach to take full advantage of economy-of-scale strategies, reducing research, development, and production costs of electric vehicles. This paper instantiates a concurrent design optimization framework, whereby different vehicle types share multiple modular powertrain components, whose size is jointly optimized to minimize the overall operational costs instead of being individually tailored. In particular, we focus on sizing battery and electric motors for a family of vehicles equipped with in-wheel motors. First, we identify a convex model of the powertrain, capturing the impact of modules' sizing and multiplicity on the mechanical power demand and the energy consumption of the vehicles. Second, we frame the concurrent powertrain design and operation problem as a second-order conic program that can be efficiently solved with global optimality guarantees. Finally, we showcase our framework for a family of three different vehicles: a city car, a compact car, and an SUV. Our results show that concurrently optimizing shared components increases the operational costs by 3.2% compared to individually tailoring them to each vehicle, a value that could be largely overshadowed by the benefits stemming from using the same components for the entire product family.

Silver nanoparticles synthesized using laser ablation synthesis in isopropanol, in absence of additional capping agents, were found to be stable with respect to both aggregation and silver oxidation over several months. The rationale for this extreme stability of metal nanoparticles suspended in organic solvents was challenging. On the basis of theoretical considerations and basic experiments it is proposed that the stabilization of silver nanoparticles involves the formation of an organic coating generated by the interaction of isopropanol molecules with the pulsed, high-energy laser beam. This coating prevents, on the one hand, any chemical reaction on colloidal nanoparticles (e.g. silver oxidation); on the other hand, the presence of the organic shell with a nature akin to that of the organic solvent led to weaker Van der Walls interactions between approaching nanoparticles enabling a larger stability than for naked metallic nanoparticles.

Nanocomposites based on polyethylene oxide and silver nanoparticles (AgNPs) were developed as new active antimicrobial and antibiofilm coatings. Silver colloids were synthesized by nanosecond-pulsed laser ablation synthesis in solution using an organic solvent to ensure a long-term stability of nanocolloids and a good solubility in polymeric solution. AgNPs were incorporated in a biodegradable polymer matrix for the preparation of composite films. The coatings’ surface chemical composition (assessed by X-ray photoelectron spectroscopy) was correlated with the ion release.

Silver nanoparticles (AgNPs) are well-known for their antimicrobial effects and several groups are proposing them as active agents to fight antimicrobial resistance. A wide variety of methods is available for nanoparticle synthesis, affording a broad spectrum of chemical and physical properties. In this work, we report on AgNPs produced by laser ablation synthesis in solution (LASiS), discussing the major features of this approach. Laser ablation synthesis is one of the best candidates, as compared to wet-chemical syntheses, for preparing Ag nano-antimicrobials. In fact, this method allows the preparation of stable Ag colloids in pure solvents without using either capping and stabilizing agents or reductants. LASiS produces AgNPs, which can be more suitable for medical and food-related applications where it is important to use non-toxic chemicals and materials for humans. In addition, laser ablation allows for achieving nanoparticles with different properties according to experimental laser parameters, thus influencing antibacterial mechanisms. However, the concentration obtained by laser-generated AgNP colloids is often low, and it is hard to implement them on an industrial scale. To obtain interesting concentrations for final applications, it is necessary to exploit high-energy lasers, which are quite expensive. In this review, we discuss the pros and cons of the use of laser ablation synthesis for the production of Ag antimicrobial colloids, taking into account applications in the food packaging field.

In this work, nanocomposites based on polyethylene oxide (PEO) and copper nanoparticles (CuNPs) for food packaging application were developed as new active packaging for fresh foodstuffs. Copper colloids were synthesized by femtosecond-pulsed laser ablation synthesis in solution (LASiS) using an organic environment, to ensure a good solubility of nanocolloids in polymeric solution. CuNPs were incorporated in a biodegradable polymer matrix for the preparation of composite films. Besides a deep morphological and spectroscopic characterization, bioactive ions release over time from composite thin films was studied by atomic absorption spectroscopy. Finally, in vivo tests on fresh-cut fruit were carried out to assess the effects of these nanocomposite systems on product quality. CuNPs-PEO composites were found effective to prevent quality decay of fruit salad. In particular, the active films allowed better preserving color and texture of fruit that remained acceptable for 3–4 days more than the control sample.