The possibility of ensuring the energy needed by a country is a fundamental requirement for the economic growth and social welfare of that country. The fulfillment of this need is particularly ...challenging for those countries that are characterized by a low level of energy self-sufficiency. The evaluation of energy security needs to consider different dimensions and is of the utmost importance as a benchmark to conceive and implement different policies. The assessment of the level of security should rely on science-based models that are able to track the rapidly evolving geopolitical scenarios, and to provide detailed information and quantitative indexes to policy decision makers. In this paper, an overarching methodology is outlined to evaluate energy security, in which its external and internal dimensions are considered and integrated: the security of the energy supply from abroad (external) and the security of national energy infrastructures (internal). Attention is then focused on the external dimension, and two indexes are defined, by means of a probabilistic approach, in terms of the expected value of supply and economic impacts. The methodology is then applied to the Italian case, considering different geopolitical scenarios, and conclusions are provided about the energy security of the country.
•Energy security involves several dimensions, including the geopolitical one.•Decision makers need tools for identifying criticalities and strategical options.•A methodology for quantitative energy supply risk assessment is proposed.•Risk scenarios and mitigation actions have been analysed in a case study.•Results show the role of corridor spatial dimension and of supply diversification.
The diffusion of smart energy systems at the local scale will lead to the implementation of innovative design, plans and applications mainly involving integrated energy infrastructures and ...distribution systems. In this framework, hydrogen will have the chance to play a major role but its penetration rate still represents a considerable uncertainty and needs to be investigated with special attention to show the real feasibility of a hydrogen economy advent.
The paper presents the results obtained analysing a set of scenarios applied to a comprehensive TIMES-based bottom-up energy model developed to describe and assess the energy systems of the single European countries and of macroareas of the rest of the world in an integrated approach. The modelling tool considers the hydrogen supply chain since its production stage (together with its storage and distribution) and evaluates – minimising the total system cost and over a mid-long time horizon – the penetration of the hydrogen-based end-use technologies.
The analysis shows that the residential and, above all, the transport sector may see a considerable diffusion of technologies supplied with hydrogen and especially for urban application, pushed by the upcoming stricter environmental constraints to the energy sector.
•Hydrogen role in local decarbonisation and in the global energy system is evaluated.•An integrated optimisation energy model has been used for scenario analyses.•Hydrogen for transportation and residential use has been specifically assessed.•A considerable share of the urban mobility can be satisfied with hydrogen buses.•Hydrogen cannot bring advantages in enhancing the EU security of energy supply.
This article gives an overall view of the mechanisms involved in the mesostructuring that takes place during the formation of surfactant‐templated inorganic materials by evaporation. Since such a ...method of preparation is well suited to fabricating thin films by dip coating, spin coating, casting, or spraying, it is of paramount interest to draw a general description of the processes occurring during the formation of self‐assembled hybrid organic/inorganic materials, taking into account all critical parameters. The following study is based on very recent works on the meso‐organization of thin silica films using tetraethylorthosilicate (TEOS) as the inorganic source and cetyltrimethylammonium bromide (CTAB) as the structuring agent, but we will show that the method can also be extended to other systems based on non‐silica oxides and block copolymer surfactants. We demonstrate that the organization depends mainly on the chemical composition of the film when it reaches the modulable steady state (MSS), where the inorganic framework is still flexible and the composition is stable after reaching an equilibrium in the diffusion of volatile species. This MSS state is generally attained seconds after the drying line, and the film's composition depends on various parameters: the relative vapor pressures in the environment, the evaporation conditions, and the chemical conditions in the initial solution. Diagrams of textures, in which the stabilized structures are controlled by local minima, are proposed to explain the complex phenomena associated with mesostructuring induced by evaporation.
An overall view of the mechanisms involved in the mesostructuring that takes place during the formation of surfactant‐templated inorganic materials by evaporation is presented. Diagrams of textures, in which the stabilized structures are controlled by local minima, are proposed to explain the complex phenomena associated with mesostructuring induced by evaporation (see Figure).
Nanocrystalline mesoporous N‐doped titania films have been prepared for the first time. The introduction of nitrogen into the anatase structure starts at 500 °C, with N bonding to titanium via oxygen ...substitution. Increasing the treatment temperature leads to the formation of TiN (TiN1–xOx) and N‐doped rutile showing mixed‐valence Ti states. Microstructural characterization shows that the ordered mesoporosity is maintained until 700 °C, where TiN (TiN1–xOx) begins to form. Optical characterization shows that the discrete introduction of N is able to shift the titania absorption edge. The photocatalytic tests give the best results under visible light excitation for the film nitrided at 500 °C. At this temperature the concentration of nitrogen in the structure is optimal since oxygen vacancies are still not important enough to promote the recombination of the photogenerated electrons and holes.
The introduction of nitrogen into titania at higher temperatures leads to the formation of TiN (TiN1–xOx), which results in nanocrystalline mesoporous N‐doped titania films (see figure). The structure of the films is investigated and their photocatalytic activity under visible‐light excitation is examined.
“Chimie douce” based strategies allow, through the deep knowledge of materials chemistry and processing, the birth of the molecular engineering of nanomaterials. This feature article will highlight ...some of the main research accomplishments we have performed during the last years. We describe successively the design and properties of: sol–gel derived hybrids, Nano Building Blocks (NBBs) based hybrid materials, nanostructured porous materials proceeds as thin films and ultra-thin films, aerosol processed mesoporous powders and finally hierarchically structured materials. The importance of the control of the hybrid interfaces via the use of modern tools as DOSY NMR, SAXS, WAXS, Ellipsometry that are very useful to evaluate in situ the hybrid interfaces and the self-assembly processes is emphasized. Some examples of the optical, photocatalytic, electrochemical and mechanical properties of the resulting inorganic or hybrid nanomaterials are also presented.
Ir Film Structural Properties for TES Application Ferrari Barusso, L.; Tugliani, S.; Fedkevych, M. ...
IEEE transactions on applied superconductivity,
08/2023, Letnik:
33, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Iridium films grown by pulsed laser deposition (PLD) show different critical temperatures ( T c ), which can be almost twice the T c of the bulk. This difference is related to the thickness and ...deposition conditions. To understand this effect, we grew different films with different configuration parameters: laser focusing, distance to the Ir target, and deposition time. We then measured the T c and analyzed the film with structural measurements by X-ray diffraction (XRD), looking at a possible correlation with the grain size of the film itself. The work was performed to determine the film growth conditions at which it is possible to obtain predetermination of T c with good accuracy using XRD pattern characteristics of Ir films.
Superconducting Transition Edge Sensors employed in X-ray astrophysics space missions were realized and fully characterized in the Low temperature detector laboratory at UniGe. Several samples of Ir ...and Ir/Au bilayer films were grown by pulsed laser deposition at different deposition rate, varying thickness and resulting variability in critical temperature (
T
c) was observed. In particular, we noticed two classes of films having discrete critical temperature (
T
c), one at about the critical temperature of the bulk Ir and one at around 1.6 times compared to the bulk. Structural characterization was made and interesting correlation between critical temperature (
T
c) and deposition conditions were found. Detailed X-Ray Diffraction investigations suggest a possible explanation of this effect with a clear correlation between microstrain value, grain size, and critical temperatures of the films. The study has been carried out to optimize the specified conditions to grow the film under which it is possible to accurately predict the critical temperature (
T
c) by analyzing the X-ray diffraction patterns of Ir/Au films.
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