Il carsharing come modalità di trasporto alternativa: una proposta di metodologia di indagine empirica

In molte città italiane è stato introdotto o si ipotizza di introdurre il carsharing (CS). In questo saggio proponiamo una possibile metodologia, consistente nella raccolta di dati sulla scelta modale tramite un questionario, da amministrare preferibilmente di persona, testata nel Friuli Venezia Giulia. Tale metodologia può rispondere a domande importanti sia per gli amministratori sia per i gestori dei servizi di CS quali: quale è la domanda potenziale di CS, chi saranno gli utenti più probabili, come varia la domanda potenziale al variare delle tariffe a cui il CS è proposto, quale tipo di modalità di funzionamento del CS (round-trip, one-way station based, one-way free-floating) è più adatta agli utenti potenziali, quale tipo di automobile è preferito (a benzina, elettrico), qual è la disponibilità a pagare per le automobili elettriche, e quali modalità di trasporto sostituirebbe il CS. Il saggio illustra il questionario ed i risultati descrittivi ed econometrici ottenuti nella indagine pilota effettuata nel Friuli Venezia Giulia

A Quadratic Model with Nonpolynomial Terms for Remote Colorimetric Calibration of 3D Laser Scanner Data Based on Piecewise Cubic Hermite Polynomials

The processing of intensity data from terrestrial laser scanners has attracted considerable attention in recent years. Accurate calibrated intensity could give added value for laser scanning campaigns, for example, in producing faithful 3D colour models of real targets and classifying easier and more reliable automatic tools. In cultural heritage area, the purely geometric information provided by the vast majority of currently available scanners is not enough for most applications, where indeed accurate colorimetric data is needed. This paper presents a remote calibration method for self-registered RGB colour data provided by a 3D tristimulus laser scanner prototype. Such distinguishing colour information opens new scenarios and problems for remote colorimetry. Using piecewise cubic Hermite polynomials, a quadratic model with nonpolynomial terms for reducing inaccuracies occurring in remote colour measurement is implemented. Colorimetric data recorded by the prototype on certified diffusive targets is processed for generating a remote Lambertian model used for assessing the accuracy of the proposed algorithm. Results concerning laser scanner digitizations of artworks are reported to confirm the effectiveness of the method

In situ investigation of the mechanochemically promoted Pd–Ce interaction under stoichiometric methane oxidation conditions

The optimization of the supported Pd phase for CH4 activation on Pd/CeO2 catalysts has been a matter of great interest in the recent literature, aiming at the design of efficient methane abatement catalysts for Natural Gas fueled Vehicles (NGVs). Under lean conditions, a mixed Pd0 /PdO combination has been indicated as exhibiting the best performance, while controversial results have been reported under stoichiometric conditions depending on the support oxide, where either Al2O3 or zeolite-based supports are usually considered. Here, by means of synchrotron-based in situ NAP-XPS and XRD measurements, we follow the evolution of Pd species on Pd/CeO2 samples prepared by dry mechanochemical synthesis (M) under stoichiometric CH4 oxidation feed, unravelling a stable Pd0 /Pd2+ arrangement in a close to 1 : 1 ratio as the most active palladium state for CH4 activation when excess oxygen is not available, in contrast to what was reported for Pd/alumina materials, where metallic Pd0 nanoparticles showed the highest activity. The combination of NAP-XPS analysis and activity test results highlights the promotional effect of the Pd–Ce interaction, resulting in enhanced oxygen transfer and improved activity and stability of the Pd/CeO2 catalyst prepared by a novel mechanochemical approach even under low O2 content, large excess of water vapor (10 vol%) and high temperature exposure (4700 1C)

Identification of highly selective surface pathways for methane dry reforming using mechanochemical synthesis of Pd-CeO2

The methane dry reforming (DRM) reaction mechanism was explored via mechanochemically prepared Pd/CeO2 catalysts (PdAcCeO2M), which yield unique Pd–Ce interfaces, where PdAcCeO2M has a distinct reaction mechanism and higher reactivity for DRM relative to traditionally synthesized impregnated Pd/CeO2 (PdCeO2IW). In situ characterization and density functional theory calculations revealed that the enhanced chemistry of PdAcCeO2M can be attributed to the presence of a carbon-modified Pd0 and Ce4+/3+ surface arrangement, where distinct Pd–CO intermediate species and strong Pd–CeO2 interactions are activated and sustained exclusively under reaction conditions. This unique arrangement leads to highly selective and distinct surface reaction pathways that prefer the direct oxidation of CHx to CO, identified on PdAcCeO2M using isotope labeled diffuse reflectance infrared Fourier transform spectroscopy and highlighting linear Pd–CO species bound on metallic and C-modified Pd, leading to adsorbed HCOO [1595 cm–1] species as key DRM intermediates, stemming from associative CO2 reduction. The milled materials contrast strikingly with surface processes observed on IW samples (PdCeO2IW) where the competing reverse water gas shift reaction predominates.Peer ReviewedPostprint (published version

Investigation of the evolution of Pd-Pt supported on ceria for dry and wet methane oxidation

Efficiently treating methane emissions in transportation remains a challenge. Here, we investigate palladium and platinum mono- and bimetallic ceria-supported catalysts synthesized by mechanical milling and by traditional impregnation for methane total oxidation under dry and wet conditions, reproducing those present in the exhaust of natural gas vehicles. By applying a toolkit of in situ synchrotron techniques (X-ray diffraction, X-ray absorption and ambient pressure photoelectron spectroscopies), together with transmission electron microscopy, we show that the synthesis method greatly influences the interaction and structure at the nanoscale. Our results reveal that the components of milled catalysts have a higher ability to transform metallic Pd into Pd oxide species strongly interacting with the support, and achieve a modulated PdO/Pd ratio than traditionally-synthesized catalysts. We demonstrate that the unique structures attained by milling are key for the catalytic activity and correlate with higher methane conversion and longer stability in the wet feed.Peer ReviewedPostprint (published version

Simulating the Diffusion of Residential Rooftop Photovoltaic, Battery Storage Systems and Electric Cars in Italy. An Exploratory Study Combining a Discrete Choice and Agent-Based Modelling Approach

Rooftop solar photovoltaic (PV) systems could significantly contribute to renewable energy production and reduce domestic energy costs. In Italy, as in other countries, the current incentives generate a modest annual increase after the generous fiscal incentives that kick-started the PV market in the 2008–2013 period. Several factors are, however, at play that can speed up the installation process, such as the improvements in PV technology at declining prices, the increased availability of battery-storage (BS) systems, the growing use of electric appliances, the uptake of electric cars, and the increased environmental awareness. We integrate two research methodologies, discrete choice modeling and agent-based modeling, to understand how these factors will influence households’ decisions regarding PV and BS installations and how agents interact in their socioeconomic environment. We predict that in Italy, given the preference structure of homeowners, the continuing decline in costs, and the social interaction, 40–45% of homeowners will have PV or PV and BS installed by 2030, thanks to the existing investment tax credit policy

Pd/CeO2 catalysts prepared by solvent-free mechanochemical route for methane abatement in natural gas fueled vehicles

The increasing diffusion of alternative mobility solutions, ranging from electric technologies to natural gas fueled vehicles (NGVs), has led to a progressive life-cycle analysis approach of their environmental impact in terms of greenhouse gases (GHGs) emissions. This new approach prompted a careful design of the NGVs catalytic aftertreatment system in order to minimize the catalytic converter carbon footprint as well as the unburned methane emissions at tailpipe. Here, a series of Pd/CeO2 methane oxidation catalysts were prepared by an environmentally friendly solvent-free method and compared to the commercial wet-synthesized state-of-the-art catalysts. Their application in NGVs aftertreatment systems was evaluated by testing powder catalysts and coated monolith cores for CH4 oxidation and steam reforming, which are the main methane abatement reactions occurring in a three-way catalyst (TWC) under lean and rich conditions, respectively. Pd/CeO2 catalysts prepared by mechanochemical synthesis initially displayed superior activity compared to their counterpart obtained by conventional wet impregnation, especially under lean oxidation conditions, but appeared less resistant to the industrial aging process after core washcoating. Lambda sweep experiments carried out under full gas composition proved that, despite needing further optimization in the washcoating and aging processes, the developed mild milling synthesis procedure is a viable way for the production of Pd/CeO2 based catalysts for natural gas TWCs.Peer ReviewedPostprint (author's final draft

Vehicle-to-ski: A V2G optimization-based cost and environmental analysis for a ski resort

Ski resorts are becoming perfect demonstrations for the integration of renewable sources. Moreover, the ever-growing global fleet of electric cars (EV) and the increase of battery capacities allow the vehicles to be used for purposes other than driving. This paper aims to study the implementation of a vehicle-to-grid (V2G) application and the development of an MPC-based energy management system (EMS) within a ski resort in the Trentino-Alto Adige Italian region. Using real data for load and production power estimation, the study analyses the economic and environmental impact in three different scenarios by considering the resort’s future trends. The results show that photovoltaic power generation has a significant impact on both cost and environmental aspects, leading to a reduction in total expenditure and CO2 of about 7%. However, assuming an increasing number of charging stations, the exploitation of V2G technology for energy arbitrage does not lead to significant total cost and CO2 reductions (~2%) for the future scenarios. Conversely, self-consumption improves (~100%) using different charging strategies. Despite this, a sensitivity analysis on PV production and a joint increase in EVs and energy price gap leads to a significant reduction in total costs of up to 7.7% and 15.2%, respectively

Outstanding Methane Oxidation Performance of Palladium-Embedded Ceria Catalysts Prepared by a One-Step Dry Ball-Milling Method

By carefully mixing Pd metal nanoparticles with CeO2 polycrystalline powder under dry conditions, an unpredicted arrangement of the Pd-O-Ce interface is obtained in which an amorphous shell containing palladium species dissolved in ceria is covering a core of CeO2 particles. The robust contact that is generated at the nanoscale, along with mechanical forces generated during mixing, promotes the redox exchange between Pd and CeO2 and creates highly reactive and stable sites constituted by PdOx embedded into CeO2 surface layers. This specific arrangement outperforms conventional Pd/CeO2 reference catalysts in methane oxidation by lowering light-off temperature by more than 50°C and boosting the reaction rate. The origin of the outstanding activity is traced to the structural properties of the interface, modified at the nanoscale by mechanochemical interaction.Postprint (author's final draft