Territorial scenarios in Europe: Growth and disparities beyond the economic crisis

Up to the start of the present economic crisis (2008), Europe was characterized by a clear trend of convergence in the GDP level of European countries, which was able to counterbalance the opposite trend in intra-national disparities that took place in many countries – namely those with a more recent accession to the Union. The economic downturn of the last years, however, has brought this process of convergence to a halt, mainly as a consequence of the tight austerity policies imposed to many southern European countries. This evidence, recognized by the European Union in the last Cohesion Report (“the crisis has reversed the process of convergence of regional GDP per head and unemployment within the EU”) brought to the fore the relevance of macroeconomic policies in regional development. Therefore in this paper, with the help of a newly built macroeconomic and regional forecasting model (MASST), the future of regional convergence / divergence in the EU is explored through four scenarios: a baseline one, recognizing the clear break of the crisis and three exploratory scenarios, depicting in a consistent way three different “territorial” strategies: supporting large metropolises vs. cities of second and third rank, vs. peripheral and lagging regions. Interestingly enough, the “cities” scenario proves to be at the same time the most cohesive and the most expansionary, shedding some doubts on the traditional equity/efficiency trade-off through an intermediate strategy based on the exploitation of a diffused territorial capital. Overall, diverging regional processes are forecasted from now to 2030

Karst of Western Cuba: Observations, Geomorphology, and Diagenesis

In Cuba, we observed many karst features in a variety of hydrogeologic settings. These hy-drogeologic settings occur in close proximity only because of the complex tectonic history of the is-land. We observed caves within rocks ranging from Pleistocene to Jurassic, and representing a range of diagenetic ages from eogenetic to teloge-netic. Our observations are from the western one-third of the island of Cuba; however, we believe they are representative of hydrogeologic settings found throughout the island

eu regional policy effectiveness and the role of territorial capital

The present chapter reviews the recent studies of the group of regional and urban economics on the impact of the European Union regional policy on regional development. In particular, the focus of the research program is on the identification of the mechanisms through which the local territorial characteristics mediate the effect of public investments. Results show a strong relationship between the territorial capital of regions and the effectiveness of the EU regional policy. This evidence conveys relevant implications for policy makers. In particular, it suggests that regions should invest in those assets that are complementary to the ones which they already have, in order to build a balanced economic system

Resistenza alla corrosione atmosferica di acciai inossidabili di largo impiego

In questo lavoro è stato studiato il comportamento a corrosione atmosferica di due tipi di acciaio inossidabile (AISI 304 e AISI 316L). Più in dettaglio, è stata dedicata particolare attenzione alla relazione esistente tra la resistenza alla corrosione e la finitura superficiale. Diversi lamierini di dimensioni 10x15 cm, caratterizzati da due finiture superficiali standard (2B e BA) sono stati esposti ad atmosfere naturali di diversa aggressività, facendo uso di appropriati telai di esposizione. Sono stati eseguiti, inoltre, test di esposizione in nebbia salina e prove di polarizzazione anodica in NaCl 3,5 %, al fine di caratterizzare dal punto di vista elettrochimico i diversi materiali in esame. Dai risultati ottenuti si è potuto constatare che il tipo di finitura superficiale influenza marcatamente la resistenza alla corrosione atmosferica. In particolare, la corrosione delle leghe con finitura 2B pregiudica l’utilizzo in atmosfera di tali materiali laddove ha importanza il fattore estetico

STUDIO DELLA CORROSIONE INTERSTIZIALE DEGLI ACCIAI INOSSIDABILI AISI 316L, AISI 304L E AISI 444

Nel presente lavoro è stata studiata la suscettibilità alla corrosione interstiziale degli acciai inossidabili austenitici AISI 316L e 304L e dell’acciaio inossidabile ferritico AISI 444. Sono stati effettuati test di immersione a 40 °C in soluzione di FeCl3 1% in peso, utilizzando formatori artificiali d’interstizio (“crevice former”); sono stati poi eseguiti test elettrochimici di polarizzazione anodica a 80 °C in una soluzione contenente 1000 mg dm-3 di Cl-, sia in presenza che in assenza di formatori d’interstizio, al fine di determinare i potenziali di corrosione localizzata per crevice e per pitting. La sperimentazione è stata eseguita sia su campioni tal quali che su campioni sottoposti a trattamento di decapaggio-passivazione con una soluzione acida a base di HF e HNO3, per migliorarne la resistenza a corrosione. Dai risultati ottenuti è emerso un certo disaccordo tra i due tipi di prove. Infatti, dai test di immersione, l’acciaio AISI 444 è risultato il peggiore in termini di resistenza a corrosione per crevice, con addirittura un ulteriore peggioramento dopo il trattamento di passivazione. I risultati dei test elettrochimici hanno invece mostrato che questo acciaio presenta potenziali d’innesco della corrosione localizzata (sia per pitting che per crevice) più elevati rispetto a quelli degli altri acciai testati; inoltre, il potenziale d’innesco della corrosione localizzata dell’acciaio AISI 444 risulta incrementato dal trattamento di passivazione appositamente realizzato

Image resonance in the many-body density of states at a metal surface

The electronic properties of a semi-infinite metal surface without a bulk gap are studied by a formalism that is able to account for the continuous spectrum of the system. The density of states at the surface is calculated within the GW approximation of many-body perturbation theory. We demonstrate the presence of an unoccupied surface resonance peaked at the position of the first image state. The resonance encompasses the whole Rydberg series of image states and cannot be resolved into individual peaks. Its origin is the shift in spectral weight when many-body correlation effects are taken into account

Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials

Quantum ESPRESSO is an integrated suite of computer codes for electronic-structure calculations and materials modeling, based on density-functional theory, plane waves, and pseudopotentials (norm-conserving, ultrasoft, and projector-augmented wave). Quantum ESPRESSO stands for "opEn Source Package for Research in Electronic Structure, Simulation, and Optimization". It is freely available to researchers around the world under the terms of the GNU General Public License. Quantum ESPRESSO builds upon newly-restructured electronic-structure codes that have been developed and tested by some of the original authors of novel electronic-structure algorithms and applied in the last twenty years by some of the leading materials modeling groups worldwide. Innovation and efficiency are still its main focus, with special attention paid to massively-parallel architectures, and a great effort being devoted to user friendliness. Quantum ESPRESSO is evolving towards a distribution of independent and inter-operable codes in the spirit of an open-source project, where researchers active in the field of electronic-structure calculations are encouraged to participate in the project by contributing their own codes or by implementing their own ideas into existing codes.Comment: 36 pages, 5 figures, resubmitted to J.Phys.: Condens. Matte

Resonant Lifetime of Core-Excited Organic Adsorbates from First Principles

We investigate by first-principles simulations the resonant electron-transfer lifetime from the excited state of an organic adsorbate to a semiconductor surface, namely isonicotinic acid on rutile TiO$_2$(110). The molecule-substrate interaction is described using density functional theory, while the effect of a truly semi-infinite substrate is taken into account by Green's function techniques. Excitonic effects due to the presence of core-excited atoms in the molecule are shown to be instrumental to understand the electron-transfer times measured using the so-called core-hole-clock technique. In particular, for the isonicotinic acid on TiO$_2$(110), we find that the charge injection from the LUMO is quenched since this state lies within the substrate band gap. We compute the resonant charge-transfer times from LUMO+1 and LUMO+2, and systematically investigate the dependence of the elastic lifetimes of these states on the alignment among adsorbate and substrate states.Comment: 24 pages, 6 figures, to appear in Journal of Physical Chemistry

Complex Stoichiometry-Dependent Reordering of 3,4,9,10-Perylenetetracarboxylic Dianhydride on Ag(111) upon K Intercalation

Alkali metal atoms are frequently used for simple yet efficient n-type doping of organic semiconductors and as an ingredient of the recently discovered polycyclic aromatic hydrocarbon superconductors. However, the incorporation of dopants from the gas phase into molecular crystal structures needs to be controlled and well understood in order to optimize the electronic properties (charge carrier density and mobility) of the target material. Here, we report that potassium intercalation into the pristine 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) monolayer domains on a Ag(111) substrate induces distinct stoichiometry-dependent structural reordering processes, resulting in highly ordered and large KxPTCDA domains. The emerging structures are analyzed by low-temperature scanning tunneling microscopy, scanning tunneling hydrogen microscopy (ST[H]M), and low-energy electron diffraction as a function of the stoichiometry. The analysis of the measurements is corroborated by density functional theory calculations. These turn out to be essential for a correct interpretation of the experimental ST[H]M data. The epitaxy types for all intercalated stages are determined as point-on-line. The K atoms adsorb in the vicinity of the oxygen atoms of the PTCDA molecules, and their positions are determined with sub-\uc5ngstr\uf6m precision. This is a crucial prerequisite for the prospective assessment of the electronic properties of such composite films, as they depend rather sensitively on the mutual alignment between donor atoms and acceptor molecules. Our results demonstrate that only the combination of experimental and theoretical approaches allows for an unambiguous explanation of the pronounced reordering of KxPTCDA/Ag(111) upon changing the K content