Higher Institute on Territorial Systems for Innovation
PORTO Publications Open Repository TOrinoNot a member yet
91193 research outputs found
Sort by
Microstructural and electrical characterization of Mn-Co spinel protective coatings for solid oxide cell interconnects
No full textAqueous Solar Cells as Emerging Photovoltaics: Photoelectrochemical and Chemometric Investigation
No full textIn recent years, with the idea of creating efficient, safe, and low-cost dye-sensitized solar cells (DSSCs), the research moved the attention towards alternative solvent-based electrolytes. Above all, DSSCs with water-based electrolytes have been proposed as one of the possible solution, providing reduced costs, non-flammability and environmental compatibility. Recently, we demonstrated that stability issues can be properly addressed by choosing the appropriate dye. Moreover, the possibility of gelling the liquid solvent into a polymeric matrix can reduce the electrolyte leakage outside the device, increasing the long-term stability. In this contribution, the investigation on a series of iodine and cobalt-based 100% aqueous electrolytes is presented to improve the photoanode/electrolyte interface in the emerging solar energy converters. Thanks to our previous experience and to a multivariate approach (design of experiment, DoE), the effects of the change in redox mediator concentrations and in photoanode preparation on DSSCs performances have been evaluated. Finally, the gelation of the best aqueous electrolytes with bio-derived polymers has been performed. Photovoltaic performances and stabilities will be discussed by comparing liquid and gel electrolytes. In lab-scale solar cells interesting photovoltaic performances superior to 4% were achieved
Vacuum Induced Surface Freezing as an effective method for cycle optimization
No full textIn recent years, special attention has been given to freezing and its control. As a matter of fact, freezing suffers from the same challenges as primary and secondary drying, from performance in specific formulations to reproducibility and batch uniformity. These challenges are made further critical if we account for the fact that potential problems in freezing impact on the product behavior during both primary and secondary drying, on product morphology, as well as on intra-vial and vial-to-vial heterogeneity. Recent literature showed that the control of temperature at which nucleation occurs is beneficial to primary drying time, but also to batch uniformity [1]. In this study, we investigate how the control of nucleation temperature, and particularly the use of Vacuum Induced Surface Freezing (VISF), can effectively reduce the total cycle time, minimize batch heterogeneity, and improve intra-vial uniformity [3]. This last aspect is not secondary to the previous advantages as uncontrolled freezing can promote a non-uniform distribution of the active ingredient within the lyophilized product and potentially their aggregation/denaturation [4]. The impact of VISF on drying is here discussed referring to both primary and secondary drying
Polymer Electrolytes Prepared by Industrially Compatible Processes for Renewable Energy Storage in Sodium Batteries
No full textWith the fast development of renewable energy sources, such as wind and solar plant, large-scale and high energy storage system are becoming extremely important to realize the load leveling of these intermittent energies into the grid. The most promising technology for that are secondary batteries (rechargeable) because high energy conversion, simple design, flexibility, easy to maintain. In order to meet the low cost policy in the market, sodium based secondary batteries are the best deal actually. However, the currently technology of batteries use liquid electrolytes as ion transport media, and these liquid electrolytes are based on organic solvents that are toxic and volatile, and the use of these flammable liquids in batteries raises safety concerns. The most powerful solution on it is switch on all solid state material such as polymer films, ceramics, etc… Here, we offer an overview of our recent developments on polymer electrolytes for Sodium-ion batteries. Polymer electrolytes were prepared through different techniques, exploiting techniques very easily to applied on an industrial point of view, simple casting and UV-curing. All samples were thoroughly characterized in the physico-chemical and electrochemical viewpoint. They exhibited excellent ionic conductivity and wide electrochemical stability window, which ensure safe operation at ambient conditions. Electrochemical performances in lab-scale devices are presented, evaluated by means of cycling voltammetry and galvanostatic charge/discharge cycling exploiting different electrode materials (prepared by water-based procedures with green carboxymethylcellulose as binder). Work on Na-ion polymer batteries for moderate temperature application is at an early stage, only lab-scale cells were demonstrated so far. Nevertheless, with the appropriate choice and optimisation of electrode/electrolyte materials (and succesfull combination thereof), the intriguing characteristics of the newly developed SPEs here presented postulates the possibility of their effective implementation in safe, durable and high energy density secondary Na-based polymer devices conceived for green-grid storage and operating at ambient and/or sub-ambient temperatures
Variabilità intra e inter-soggetto della misura del livello di pressione sonora
No full textIl presente studio stima le variabilità del livello di pressione sonora (SPL) in un soggetto e in un gruppo di soggetti, dette rispettivamente variabilità intra- e inter-soggetto. 17 studenti hanno letto 2 brani e il segnale è stato acquisito da un fonometro, un microfono ad archetto e un analizzatore vocale. La variabilità è stata valutata per SPL medio, moda e equivalente in ogni dispositivo. La variabilità intra-soggetto massima ottenuta è di 2,0 dB, mentre quella inter-soggetto è di 5,3 dB
Potenziamento neurocognitivo e buona acustica a scuola per la prevenzione della dislessia
No full textIl progetto Io-Ascolto, sostenuto dalla Fondazione CRT dal 2015, vuole sperimentare un metodo di prevenzione della dislessia che sia integrato nella pratica didattica ancor prima che questo disturbo possa essere diagnosticato. Si basa sul potenziamento neurocognitivo per migliorare i pre-requisiti della lettura e la lettura stessa, e sull'effetto dell'acustica delle aule scolastiche sull'apprendimento della lettura in termini di chiarezza ed intelligibilità
