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Abstract COVID-19 has dramatically affected financial markets, economies, and societies worldwide and exposed pre-existing inequalities in cities. This work aims to understand the inequalities in some cities worldwide, their reasons and circumstances, and impacts to drive lessons for future prevention, intervention, and post-catastrophe/ hazard plans such as COVID-19 that would raise resilience and decrease damages. Six major cities were included in the analysis and contrasted based on specific assessment criteria. The study included the impact of the pandemic on the economy and the government's responses global crisis. Additionally, newfound measures and technologies developed to control the hazard, including the community's response and cooperation to solving the issue were explored. The outcomes of this work shed a light on problems to be addressed in the future towards enhances the resilience of cities pre- and post- global crisis. Through the comparisons made in this paper, conclusions regarding the cities' successful combat against COVID-19 were drawn. According to the comparative analysis, it became apparent that poverty, culture, and governance are primary factors that control the success of states under emergency. Moreover, it is understood that technology is a significant factor in combating pandemics and health emergencies as large as COVID-19, especially for tracking and monitoring.

This study focuses on the design of a new Ti based multicomponent amorphous alloy for the development of biocompatible implant materials with enhanced hemocompatibility and cytocompatibility. While this class of amorphous alloys has shown its potential for biomedical implant applications, there are major concerns due to the presence of elements such as copper which can lead to cytotoxicity in the human body during long term implantation. Nevertheless, copper is indispensable in the development of an amorphous alloy. Thus, the objective of this work is to selectively remove copper from the surface of the Ti40Cu40Zr11Fe3Sn3Ag3 (at%) amorphous alloy using the dealloying technique and produce a patterned protective passivated surface rich in Ti and Zr oxides. Nitric acid (HNO3) has been found to be effective in depleting copper from the sample surface. Optimization of treatment parameters such as temperature (70 °C and room temperature) yielded drastic differences in the morphology of the samples studied using Field-Emission Scanning Electron Microscopy. The treated sample surface demonstrated good hemocompatibility and cytocompatibility with primary human osteoblast cells (HOb) and human osteosarcoma cell line (Saos-2). Additionally, the treated samples showed higher ability to produce reactive oxygen species with respect to pristine samples, which could be convenient for preserving the implant from bacterial contamination. These findings contribute to the advancement of producing copper-depleted nanostructured Ti based amorphous alloys for biomedical implant applications.

Outdoor bronze statues are constantly exposed to weather conditions and reactive compounds in the atmosphere that can interact with their surfaces. To avoid these interactions, a commonly used method is the application of coatings with corrosion inhibitors. However, a significant limitation of these inhibitors is their gradual loss over time. In this study, we aimed to improve the durability of 5-ethyl-1,3,4-thiadiazol-2-amine (AEDTA), the inhibitor chosen to formulate new acrylic coatings for outdoor bronzes. Methyl-β-cyclodextrin (Me-β-CD) was selected to host the inhibitor due to the capability of cyclodextrins to form complexes incorporating small organic molecules. The complexes of Me-β-CD and AEDTA were prepared and the inclusion of AEDTA was proved by Fourier-transform infrared spectroscopy, X-ray diffraction and nuclear magnetic resonance spectroscopy. Then, acrylic coatings were prepared at different concentrations of the Me-β-CD/AEDTA system. They were thermally aged and monitored every 24 h. To evaluate the volatilization of the corrosion inhibitor, solid phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) and thermal desorption-GC/MS (TD-GC/MS) analyses were performed during the first 72 h. The results were compared to those of pure AEDTA films and Incralac®. The outcomes showed that Me-β-CD/AEDTA complexes are promising candidates for developing coatings with improved stability and longer retention of AEDTA.

Magnetic vortices have been an interesting element in the past decades due to their flux-closure domain structures which can be stabilized at ground states in soft ferromagnetic microstructures. In this work, vortex states are shown to be nucleated and stabilized in Fe80Ga20 and Fe70Ga30 disks, which can be an upcoming candidate for applications in strain-induced electric field control of magnetic states owing to the high magnetostriction of the alloy. The magnetization reversal in the disks occurs by the formation of a vortex, double vortex or S-domain state. Micromagnetic simulations have been performed using the FeGa material parameters and the simulated magnetic states are in good agreement with the experimental results. The studies performed here can be essential for the use of FeGa alloy in low-power electronics.

Abstract Flexible materials have brought up a new era of application-based research in stretchable electronics and wearable devices in the last decade. Tuning of magnetic properties by changing the curvature of devices has significant impact in the new generation of sensor-based technologies. In this work, magnetostrictive FeGa thin films have been deposited on a flexible Kapton sheet to exploit the magneto-elastic coupling effect and modify the magnetic properties of the sample. The FeGa alloy has high magnetostriction constant and high tensile strength making its properties susceptible to external stress. Tensile or compressive strain generated by the convex or concave states influence the uniaxial magnetic anisotropy of the system. Low temperature measurements show a hard magnetic behavior and the presence of exchange-bias effect after field cooling to 2 K. The results obtained in this study prove essential for the development of flexible electronics.

Artificial magnetoelectric materials possess huge potential to be utilized in the development of energy efficient spintronic devices. In the past decade, the search for a good ferromagnetic/ferroelectric combination having the ability to create high magnetoelectric coupling, created new insights and also new challenges. In this report, the magnetoelectric effect is studied in the FeGa/PMN-PT(001) multiferroic heterostructures in the presence of electric fields via strain-mediated effects. The formation of magnetic anisotropy in FeGa is observed after changing the polarization of PMN-PT to out-of-plane orientations. The magnetic domain structures forming during the magnetization reversal were studied in compressive, tensile and remanent strained states. The changes in the magnetic properties were reversible after each cycling of the electric field polarity, hence creating a non-volatile system. The control of magnetization switching sustained by an ON–OFF electric field makes our multiferroic heterostructure suitable for application in low-power magnetoelectric based memory applications.

In this review, we compared nine different chemical compositions and several heat treatments applied on quenching and partitioning steels investigated in the literature. All of these parameters were correlated to the reported mechanical properties (e.g., yield, tensile strength, elongation and toughness). Sustainability and a circular economy approach for applications in the automotive sector were also considered, providing hints for lightweighting in the car industry and the next possible steps to improve the decarbonization of the steel industry.

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Dense and mesoporous FePd nanowires (NWs) with 45 to 60 at.% Pd content were successfully fabricated by template- and micelle-assisted pulsed potentiostatic electrodeposition using nanoporous anodic alumina and polycarbonate templates of varying pore sizes. An FePd electrolyte was utilized for obtaining dense NWs while a block copolymer, P-123, was added to this electrolyte as the micelle-forming surfactant to produce mesoporous NWs. The structural and magnetic properties of the NWs were investigated by electron microscopy, X-ray diffraction, and vibrating sample magnetometry. The as-prepared NWs were single phase with a face-centered cubic structure exhibiting 3.1 µm to 7.1 µm of length. Mesoporous NWs revealed a core-shell structure where the porosity was only witnessed in the internal volume of the NW while the outer surface remained non-porous. Magnetic measurements revealed that the samples displayed a soft ferromagnetic behavior that depended on the shape anisotropy and the interwire dipolar interactions. The mesoporous core and dense shell structure of the NWs were seen to be slightly affecting the magnetic properties. Moreover, mesoporous NWs performed excellently as SERS substrates for the detection of 4,4′-bipyridine, showing a low detection limit of 10−12 M. The signal enhancement can be attributed to the mesoporous morphology as well as the close proximity of the embedded NWs being conducive to localized surface plasmon resonance.

The connection of multidisciplinary and versatile techniques capable of depositing and modeling thin films in multistep complex fabrication processes offers different perspectives and additional degrees of freedom in the realization of patterned magnetic materials whose peculiar physical properties meet the specific needs of several applications. In this work, a fast and cost-effective dealloying process is combined with a fast, low-cost, scalable electroless deposition technique to realize hybrid magnetic heterostructures. The gold nanoporous surface obtained by the dealloying of an Au40Si20Cu28Ag7Pd5 ribbon is used as a nanostructured substrate for the electrodeposition of cobalt. In the first steps of the deposition, the Co atoms fill the gold pores and arrange themselves into a patterned thin film with harder magnetic properties; then they continue their growth into an upper layer with softer magnetic properties. The structural characterization of the hybrid magnetic heterostructures is performed using an X-ray diffraction technique and energy-dispersive X-ray spectroscopy, while the morphology of the samples as a function of the electrodeposition time is characterized by images taken in top and cross-section view using scanning electron microscopy. Then, the structural and morphologic features are correlated with the room-temperature magnetic properties deduced from an alternating-gradient magnetometer’s measurements of the hysteresis loop and first order reversal curves.

Fe and Pd thin film samples have been fabricated in a rapid fashion utilizing the versatile technique of dynamic hydrogen bubble template (DHBT) method via potentiostatic electrodeposition over a copper substrate. The morphology of the samples is dendritic, with the composition being directly proportional to the deposition time. All the samples have been tested as SERS substrates for the detection of Rhodamine 6G (R6G) dye. The samples perform very well, with the best performance shown by the Pd samples. The lowest detectable R6G concentration was found to be 10−6 M (479 μgL−1) by one of the Pd samples with the deposition time of 180 s. The highest enhancement of signals noticed in this sample can be attributed to its morphology, which is more nanostructured compared to other samples, which is extremely conducive to the phenomenon of localized surface plasmon resonance (LSPR). Overall, these samples are cheaper, easy to prepare with a rapid fabrication method, and show appreciable SERS performance.

Sputtering and electrodeposition are among the most widespread techniques for metallic thin film deposition. Since these techniques operate under different principles, the resulting films typically show different microstructures even when the chemical composition is kept fixed. In this work, films of Fe70Pd30 were produced in a thickness range between 30 and 600 nm, using both electrodeposition and sputtering. The electrodeposited films were deposited under potentiostatic regime from an ammonia sulfosalicylic acid-based aqueous solution. Meanwhile, the sputtered films were deposited from a composite target in radio frequency regime. Both approaches were proven to yield high quality and homogenous films. However, their crystallographic structure was different. Although all films were polycrystalline and Fe and Pd formed a solid solution with a body-centered cubic structure, a palladium hydride phase was additionally detected in the electrodeposited films. The occurrence of this phase induced internal stress in the films, thereby influencing their magnetic properties. In particular, the thickest electrodeposited Fe70Pd30 films showed out-of-plane magnetic anisotropy, whereas the magnetization easy axis lied in the film plane for all the sputtered films. The domain pattern of the electrodeposited films was investigated by magnetic force microscopy. Finally, nanoindentation studies highlighted the high quality of both the sputtered and electrodeposited films, the former exhibiting higher reduced Young’s modulus and Berkovich hardness values.

The research described in this article concerns the issue of accessibility with a focus on the walkability in a city that is under reconstruction, such as the city of L'Aquila struck by a destructive earthquake in 2009. The reconstruction is determining a new urban layout in which there is a chaotic overlap of flows of the movements of vehicles and people, quite exceptional with respect to the configuration of an ordinary city. For example, the flows of heavy vehicles and work machines, linked to building reconstruction, and which also generate strong noise pollution and therefore a new soundscape, increase considerably. It is a city in which the return to the residences mixes with large building sites, in which urban transformations are very fast and must be governed through appropriate urban design instruments. The main aim of this research is to define a strategy to realize a method able to calculate at the same time an overlapping indexes in order to classify streets according to how friendly they are for the pedestrian and bike. This theme is approached to a methodological level and is related to the interacting theme of urban design and new centralities. The tool used for this integration is the Strategic Urban Project, which the research experience has found to be more effective and with greater performance than the more traditional Land Use Planning. The design approach and methodology is to integrate urban design techniques with spatial planning techniques, in order to obtain a higher performance of pedestrian networks.

In this study, nanoporous gold (NPG) was synthesized by free corrosion dealloying of an amorphous precursor, Au20Cu48Ag7Pd5Si20 (at. %), in a mixture of nitric and hydrofluoric acid, starting from amorphous melt-spun ribbons. NPG revealed a 3D nanoporous structure composed of pores and multigrain ligaments of an average size of 60 nm. NPG was further anodized in oxalic acid at 8 V vs. Ag/AgCl reference electrode to obtain a bimodal morphology composed of ligaments disrupted in finer features. Both NPG and anodized samples (A-NPG) were found to be mechanically stable to bending and active for surface-enhanced Raman scattering (SERS). SERS activity of samples was investigated using 4,4′-bipyridine as a probe molecule. A detection limit of 10−16 M was found for both samples, but in A-NPG, the signal was strongly enhanced. The extremely high enhancement obtained for A-NPG is attributed both to the small size of ligaments and crystals of which they are made, as well as to the nanometric features resulting from anodization treatment. Such a microstructure showed homogenous SERS response in terms of average enhancement all across the surface, as demonstrated by mapping measurements. Furthermore, NPG and A-NPG were tested as electrodes for electrocatalytic applications, showing good properties. The engineering steps from the amorphous precursor to A-NPG led us to obtain a high-sensing platform, with extremely low detection limit and intrinsic properties, that might significantly contribute to the cutting-edge technology of the future.

In this work, Fe–X (X = Cu, Pd) submicron-scale structures were electrodeposited onto pre-patterned substrates prepared by e-beam lithography. The FeCu and FePd (with reduced Pd content) systems were investigated as attractive candidates for a variety of potential applications in magnetic data storage and biomedicine. Confined growth in the restricted cavities resulted in a nanoscale grain size leading to well-defined geometries with sharp edges and corners and an average height of up to 215 nm. Specifically, nine 100 μm × 100 μm arrays of three geometries (cylindrical, rectangular and cruciform) in three different sizes were created. In addition, the total deposition time ranged from 3.5 s (FeCu) to 200 s (FePd), i.e. much faster than by traditional physical vapor deposition approaches and was performed at ambient conditions. Magnetic force microscopy for the cylindrical and cruciform structures revealed virtually no contrast at zero field, suggesting magnetic curling effects (instead of coherent rotation) during magnetization reversal. These curling effects result in low values of remanent magnetization, which is advantageous in minimizing dipolar interactions between the structures either when they are deposited onto the substrate or eventually dispersed in a liquid (e.g. in biomedical applications, as drug delivery carriers, where particle agglomeration is undesirable).

Advances in nanofabrication techniques are undoubtedly needed to obtain nanostructured magnetic materials with physical and chemical properties matching the pressing and relentless technological demands of sensors. Solid-state dewetting is known to be a low-cost and “top-down” nanofabrication technique able to induce a controlled morphological transformation of a continuous thin film into an ordered nanoparticle array. Here, magnetic Fe70Pd30 thin film with 30 nm thickness is deposited by the co-sputtering technique on a monocrystalline (MgO) or amorphous (Si3N4) substrate and, subsequently, annealed to promote the dewetting process. The different substrate properties are able to tune the activation thermal energy of the dewetting process, which can be tuned by depositing on substrates with different microstructures. In this way, it is possible to tailor the final morphology of FePd nanoparticles as observed by advanced microscopy techniques (SEM and AFM). The average size and height of the nanoparticles are in the ranges 150–300 nm and 150–200 nm, respectively. Moreover, the induced spatial confinement of magnetic materials in almost-spherical nanoparticles strongly affects the magnetic properties as observed by in-plane and out-of-plane hysteresis loops. Magnetization reversal in dewetted FePd nanoparticles is mainly characterized by a rotational mechanism leading to a slower approach to saturation and smaller value of the magnetic susceptibility than the as-deposited thin film.

This paper aims at addressing the exploitation of solid-state carriers for hydrogen storage, with attention paid both to the technical aspects, through a wide review of the available integrated systems, and to the social aspects, through a preliminary overview of the connected impacts from a gender perspective. As for the technical perspective, carriers to be used for solid-state hydrogen storage for various applications can be classified into two classes: metal and complex hydrides. Related crystal structures and corresponding hydrogen sorption properties are reviewed and discussed. Fundamentals of thermodynamics of hydrogen sorption evidence the key role of the enthalpy of reaction, which determines the operating conditions (i.e., temperatures and pressures). In addition, it rules the heat to be removed from the tank during hydrogen absorption and to be delivered to the tank during hydrogen desorption. Suitable values for the enthalpy of hydrogen sorption reaction for operating conditions close to ambient (i.e., room temperature and 1–10 bar of hydrogen) are close to 30 kJ·molH2−1. The kinetics of the hydrogen sorption reaction is strongly related to the microstructure and to the morphology (i.e., loose powder or pellets) of the carriers. Usually, the kinetics of the hydrogen sorption reaction is rather fast, and the thermal management of the tank is the rate-determining step of the processes. As for the social perspective, the paper arguments that, as it occurs with the exploitation of other renewable innovative technologies, a wide consideration of the social factors connected to these processes is needed to reach a twofold objective: To assess the extent to which a specific innovation might produce positive or negative impacts in the recipient socioeconomic system and, from a sociotechnical perspective, to explore the potential role of the social components and dynamics in fostering the diffusion of the innovation itself. Within the social domain, attention has been paid to address the underexplored relationship between the gender perspective and the enhancement of hydrogen-related energy storage systems. This relationship is taken into account both in terms of the role of women in triggering the exploitation of hydrogen-based storage playing as experimenter and promoter, and in terms of the intertwined impact of this innovation in their current conditions, at work, and in daily life.

Characterized by a large surface area to volume ratio, nanostructured metal oxides possess unique chemical and physical properties with applications in electronics, catalysis, sensors, etc. In this study, Mo3Al8, an intermetallic compound, has been used as a precursor to obtain nanostructured molybdenum oxides. It was prepared into ribbons by arc-melting and melt-spinning techniques. Single and double-step free corrosion of the as-quenched material have been studied in 1 M KOH, 1 M HF and 1.25 M FeCl3 at room temperature. In both cases, nanostructured molybdenum oxides were obtained on a surface layer a few microns thick. Two of the as-prepared samples were tested for their electrocatalytic capability for hydrogen evolution reaction (HER) in 0.5 M H2SO4 giving low onset potential (−50 mV, −45 mV), small Tafel slopes (92 mV dec−1, 9 mV dec−1) and high exchange current densities (0.08 mA cm−2, 0.35 mA cm−2 respectively). The proposed nanostructured molybdenum oxides are cost-effective and sustainable due to the cheap and abundant starting material used and the simple synthetic route, paving the way for their possible application as HER electrocatalysts.

FePd alloys in the thin film form represent a multipurpose and versatile material with relevant chemical and physical properties studied in different research fields. Moreover, the ability to manipulate and fine-tune the film surface with nanometric scale precision represents a degree of freedom useful to adapt these thin film properties to the demands of different desired applications. In this manuscript, Fe70Pd30 (at. %) thin films are prepared with a thickness of 50 and 200 nm by means of the widely used co-sputtering deposition technique. Subsequently, selective removal of the iron element from the alloy and the consequent surface diffusion of the palladium was induced by a dealloying treatment under free corrosion conditions in hydrochloric acid. The size and shape of the grains of the as-deposited thin films determine the dissolution rate of the iron element with a direct consequence not only on the surface morphology and the stoichiometry of the alloy but also on the wetting and magnetic properties of the sample. X-ray diffraction, Scanning Electron Microscopy (SEM) images, contact angle and magnetic measurements have been performed to provide a thorough characterisation of the fundamental properties of these nanostructured bimetallic thin films.

The University of Turin embossed emblem even now in use had been rediscovered in 1925. Its origin dates back to 1615 in a wax seal kept in the State Archive of Turin. Since then it has been drawn in different style on official records, diplomas, stamps and academic bulletins. By means of pictures the paper illustrates the history of this emblem from 17th century to 20th century and the symbolic elements which are figured on it (an eagle looking at the sun, a bull, three books and three small marks on each of them). The authors show a new philological interpretation of the Turin University seal which is based not only on the previously mentioned records, but also on the thin, small silver plate emblem recently acquired by the University Historical Archive and on the results of chemical and micromorphological analysis of this find.

Nanoscale magnetic materials are the basis of emerging technologies to develop novel magnetoelectronic devices. Self-assembly of polystyrene nanospheres is here used to generate 2D hexagonal dot arrays on Fe50Pd50 thin films. This simple technique allows a wide-area patterning of a magnetic thin film. The role of disorder on functional magnetic properties with respect to conventional lithographic techniques is studied. Structural and magnetic characteristics have been investigated in arrays having different geometry (i.e. dot diameters, inter-dot distances and thickness). The interplay among microstructure and magnetization reversal is discussed. Magnetic measurements reveal a vortex domain configuration in all as-prepared films. The original domain structure changes drastically upon thermal annealing performed to promote the transformation of disordered A1 phase into the ordered, tetragonal L10 phase. First-order reversal magnetization curves have been measured to rule out the role of magnetic interaction among crystalline phases characterized by different magnetic coercivity.

In this paper, hydrogen coupled with fuel cells and lithium-ion batteries are considered as alternative energy storage methods. Their application on a stationary system (i.e., energy storage for a family house) and a mobile system (i.e., an unmanned aerial vehicle) will be investigated. The stationary systems, designed for off-grid applications, were sized for photovoltaic energy production in the area of Turin, Italy, to provide daily energy of 10.25 kWh. The mobile systems, to be used for high crane inspection, were sized to have a flying range of 120 min, one being equipped with a Li-ion battery and the other with a proton-exchange membrane fuel cell. The systems were compared from an economical point of view and a life cycle assessment was performed to identify the main contributors to the environmental impact. From a commercial point of view, the fuel cell and the electrolyzer, being niche products, result in being more expensive with respect to the Li-ion batteries. On the other hand, the life cycle assessment (LCA) results show the lower burdens of both technologies.

An emergence of the disaster resilience concept broadens the idea of urban risk management and, at the same time, enhances a theoretical aspect in a way in which we can develop our cities without making it more vulnerable to natural disasters. Nevertheless, this theoretical plausibility is hardly translated into a practical implication for urban planning, as the concept of resilience remain limited to some scholars’ debate. One of substantial factors that limit the understanding of people about disaster risk an resilience is a lack of risk awareness and risk preparedness, which can be solved by restructuring social learning process that enable a process of mutual learning between experts and the public. This study, therefore, focuses on providing insights into the difficulties of disaster risk communication we face, and how gaming simulation can be taken as a communication technique in enhancing social learning, which is regarded as a fundamental step of disaster risk management prior the mitigation process takes place. The study argues that the gaming simulation can facilitate planners in acquiring risk information from the community, conceiving the multitude of complex urban physical and socio-economic components, and conceptualizing innovative solutions to cope with disaster risks mutually with the public.