Following the objectives set by COP26 and the milestones established by the European Union (EU) in the world of mobility, more and more road freight companies are starting an evolution process. ...Transport sector represents still the 30% of CO 2 emission and in 2020 the heavy truck sector emissions reaches significant values: 1776 MtCO 2 . To face this problem and meets the requirements proposed by EU several companies begin to study the adoptable solutions for decarbonization. Therefore, they proposed several options to reduce emissions and increase efficiency in particular road electrification and platooning. Therefore, this work wants to analyze these technologies on the market, and then it tries to apply them in a real case, verifying if the electrical infrastructure requirements are respected in different scenarios. Finally, several considerations on the model and on the market are observed, in order to provide realistic expectations for the future.
The aim of this work is to analyze the possibility to introduce the Vehicle to Grid (V2G) technology in a Local Public Transport (LPT) bus service in the city of Milan in Italy. The research in ...focused on the bus fleet of ATM - Azienda Trasporti Milanesi - the public company that manages collective transport in the city of Milan. This work is enhanced by the rolling stock renewal campaign in course, providing an interesting future scenario, where mobility service is fully integrated with energy distribution service. The feasibility analysis is divided into two parts. The first one concerns an energy assessment comparing the energy demand and the energy available from the stationary buses in two depots managed by ATM. The second financial evaluation involves an estimate of the costs and revenues associated with energy trading during V2G service of the two depots. The analysis represents a valuable input to support the decision-making process related to the implementation of the V2G service by the transport and energy distribution companies.
An antireflection coating (ARC) for silicon devices operating at 10 μm has been designed, fabricated and validated. The ARC is based on ZnS and Al2O3 and is deposited at room temperature. Both single ...and double side ARCs are considered, demonstrating a transmission enhancement respectively of 66% and 89% with respect to an uncoated silicon device.
Flat top formation in self-assisted GaAs nanowires Somaschini, Claudio; Fedorov, Alexey; Bietti, Sergio ...
2015 1st Workshop on Nanotechnology in Instrumentation and Measurement (NANOFIM),
2015-Jul.
Conference Proceeding
We identified the growth conditions which lead to the formation of a flat top facet in GaAs nanowires, grown by the self-assisted method in molecular beam epitaxy. Low arsenic overpressure, ...intermediate temperature and relatively long annealing time are needed to transform the Ga droplets present at the top of the nanowires into a flat GaAs segment. This result opens the possibility to realize atomically sharp heterointerfaces in this type of semiconductor nanowires.
The incubation time preceding nucleation and growth of surface nanostructures is interesting from a fundamental viewpoint but also of practical relevance as it determines statistical properties of ...nanostructure ensembles such as size homogeneity. Using in situ reflection high-energy electron diffraction, we accurately deduce the incubation times for Ga-assisted GaAs nanowires grown on unpatterned Si(111) substrates by molecular beam epitaxy under different conditions. We develop a nucleation model that explains and fits very well the data. We find that, for a given temperature and Ga flux, the incubation time always increases with decreasing As flux and becomes infinite at a certain minimum flux, which is larger for higher temperature. For given As and Ga fluxes, the incubation time always increases with temperature and rapidly tends to infinity above 640 {\deg}C under typical conditions. The strong temperature dependence of the incubation time is reflected in a similar variation of the nanowire number density with temperature. Our analysis provides understanding and guidance for choosing appropriate growth conditions that avoid unnecessary material consumption, long nucleation delays, and highly inhomogeneous ensembles of nanowires. On a more general ground, the existence of a minimum flux and maximum temperature for growing surface nanostructures should be a general phenomenon pertaining for a wide range of material-substrate combinations.
We present a unified model of compound semiconductor growth based on kinetic Monte Carlo simulations in tandem with new experimental results that can describe and predict the mechanisms for the ...formation of various types of nanostructures observed during droplet epitaxy. The crucial features of the model include the explicit and independent representation of atoms with different species and the ability to treat solid and liquid phases independently. Using this model, we examine nanostructural evolution in droplet epitaxy. The model faithfully captures several of the experimentally observed structures, including compact islands and nanorings. Moreover, simulations show the presence of Ga/GaAs core-shell structures that we validate experimentally. A fully analytical model of droplet epitaxy that explains the relationship between growth conditions and the resulting nanostructures is presented, yielding key insight into the mechanisms of droplet epitaxy.
What makes three dimensional semiconductor
quantum nanostructures so attractive is the possibility to
tune their electronic properties by careful design of their
size and composition. These ...parameters set the
confinement potential of electrons and holes, thus
determining the electronic and optical properties of the
nanostructure. An often overlooked parameter, which has
an even more relevant effect on the electronic properties
of the nanostructure, is shape. Gaining a strong control
over the electronic properties via shape tuning is the key
to access subtle electronic design possibilities. The Pulsed
Dropled Epitaxy is an innovative growth method for the
fabrication of quantum nanostructures with highly
designable shapes and complex morphologies. With
Pulsed Dropled Epitaxy it is possible to combine different
nanostructures, namely quantum dots, quantum rings
and quantum disks, with tunable sizes and densities, into
a single multi‐function nanostructure, thus allowing an
unprecedented control over electronic properties.
Despite elevated serum uric acid (eSUA) has been identified as independent risk factor for cardiovascular diseases, its prognostic value in the setting of ST-segment elevation myocardial infarction ...(STEMI) is still controversial. Although the mechanisms of this possible relationship are unsettled it has been suggested that eSUA could trigger the inflammatory response. This study sought to investigate the association between eSUA with short- and long-term mortality and with inflammatory response in patients with STEMI treated with primary percutaneous coronary intervention (pPCI).
Blood samples were collected on admission and at 24 and 48 h after pPCI: the inflammatory biomarkers C-reactive protein (CRP), neutrophil count and neutrophil to lymphocytes ratio (NLR) were considered. Baseline eSUA was defined as ≥6.8 mg/dl. Cumulative 30-days and 1-year mortalities were estimated using the Kaplan-Meyer analysis. Multivariable analyses were performed by Cox proportional hazard models.
In the 2369 patients with STEMI considered, 30-day mortality was 5.8% among patients with eSUA and 2% among patient with normal SUA level (p < 0.001); 1-year mortality was 8.5% vs 4%, respectively (p < 0.001). At multivariable analyses eSUA was an independent predictor of 30-day mortality (HR 1.196, 95%CI 1.006–1.321, p = 0.042) and 1-year mortality (HR 1.178, 95%CI 1.052–1.320, p = 0.005). eSUA patients presented higher values in on admission CRP (p < 0.001) and in neutrophil count and NLR at 24 h (respectively, p = 0.020 and p < 0.001) and at 48 h (p = 0.018 and p < 0.001) compared to patients with normal SUA levels.
Elevated serum uric acid is associated with higher short- and long-term mortality and with a greater inflammatory response after reperfusion in patients with STEMI treated with primary PCI.
•Patients with STEMI and elevated SUA have a greater inflammatory response after pPCI.•Elevated SUA is independently associated with short and long-term mortality after pPCI.•There is a threshold effect for SUA levels (≥6.7 mg/dl) on mortality after STEMI.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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