Atlante degli allegati grafici alle schede d’ambito paesaggistico

L’Atlante degli allegati grafici alle schede d’ambito paesaggistico è uno strumento complementare agli elaborati del Piano Territoriale a valenza paesaggistica della Regione Friuli Venezia Giulia che, attraverso elaborazioni grafiche e apparati iconografici selezionati, consente una visualizzazione immediata dei caratteri molteplici del paesaggio regionale. Nelle tavole dell’Atlante le informazioni contenute nella prima sezione delle schede degli ambiti paesaggistici - Analisi del territorio ed individuazione di valori e fattori di rischio paesaggistico (art. 143, comma 1, lett. a), c), D. Lgs. 42/2004), sono associate a materiali iconografici e diagrammi che descrivono la morfologia dei luoghi. Le planimetrie schematiche di ciascun ambito consentono un’agevole localizzazione di questo all’interno del territorio regionale, e nel contempo evidenziano le relazioni che all’interno di quest’ultimo derivano dalla rete delle infrastrutture. Le sezioni diagrammatiche degli elementi notevoli del paesaggio, mediante simboli e didascalie, consentono di leggere nel dettaglio configurazioni specifiche, modificazioni del suolo e assetti insediativi. La cartografia storica, che comprende la Kriegskarte (redatta tra il 1798 ed il 1805) e la Carta Corografica del Litorale (risalente alla prima metà del XIX sec.), consente una lettura della morfologia e degli elementi caratterizzanti del paesaggio in una fase precedente alle grandi trasformazioni insediative del secolo scorso. I caratteri naturali, agricoli e insediativi sono documentati attraverso una selezione della documentazione fotografica predisposta dal personale del Servizio Tutela Beni Paesaggistici della Regione, integrata ove necessario da materiali originali. I valori e i fattori di rischio paesaggistico, anch’essi esplicitati nelle schede d’ambito, sono visualizzati mediante documentazione fotografica e localizzati graficamente sullo stralcio planimetrico dell’ortofoto

Characterization of FeOOH nanoparticles and amorphous silica matrix in an FeOOH-Sio 2 nanocomposite

A nanocomposite with an FeOOH/SiO2ratio equal to 17.7 wt% and the pertinent matrix, obtained by etching away the nanoparticles through reaction with hydrochloric acid, were investigated by XRD, TGA-DTA, heliostereopicnometry, BET, and TEM techniques. The study shows the presence in the nanocomposite of ferrihydrite nanoparticles phase with average dimensions around 4 nm. The FeOOH nanoparticles structure was analyzed by synchrotron X-ray diffraction data using the distribution difference curve method. The porous structure of the matrix resulting by etching away the nanoparticles differs significantly from that of a pureSiO2sample obtained by hydrolysis of TEOS under the same operative conditions followed in the nanocomposite preparation

Cross-Disciplinary Approaches to the Regeneration of Minor Historical Centers: The Case of Mogoro in Sardinia

In Italy, the regeneration of historic centers is a relevant issue in the theoretical debate and practice of urban planning, a discourse which usually adopts strictly constraining approaches and tools directed almost exclusively at the preservation of the traditional characters of historic build- ings, neglecting social and economic processes. In particular, the redevelopment of minor historic centers becomes a priority action for the revitalisation of marginal territories affected by the phe- nomena of depopulation and weakening of the socio-economic structure. The paper focuses on the regional context of Sardinia to investigate methods and criteria for the drafting of planning tools for the redevelopment of minor historic centers, enabling the definition and implementation of strate- gies in accordance with the objectives and guidelines of the Regional Landscape Plan. With a case study methodology applied to the historic center of Mogoro, the research discusses an innovative and interdisciplinary approach to the definition of flexible regulations to manage the urban regen- eration process

Redox Centers Evolution in Phospho-Olivine Type (LiFe0. 5Mn0. 5 PO4) Nanoplatelets with Uniform Cation Distribution

Accepted Version of the publication: Nano Lett. 2014, 14, 3, 1477–1483. Publication Date: February 24, 2014. https://doi.org/10.1021/nl4046697 © 2014 American Chemical Society. In phospho-olivine type structures with mixed cations (LiM1M2PO4), the octahedral M1 and M2 sites that dictate the degree of intersites order/disorder play a key role in determining their electrochemical redox potentials. In the case of LiFexMn1−xPO4, for example, in micrometer-sized particles synthesized via hydrothermal route, two separate redox centers corresponding to Fe2+/Fe3+ (3.5 V vs Li/Li+) and Mn2+/Mn3+ (4.1 V vs Li/Li+), due to the collective Mn−O−Fe interactions in the olivine lattice, are commonly observed in the electrochemical measurements. These two redox processes are directly reflected as two distinct peak potentials in cyclic voltammetry (CV) and equivalently as two voltage plateaus in their standard charge/discharge characteristics (in Li ion batteries). On the contrary, we observed a single broad peak in CV from LiFe0.5Mn0.5PO4 platelet-shaped (∼10 nm thick) nanocrystals that we are reporting in this work. Structural and compositional analysis showed that in these nanoplatelets the cations (Fe, Mn) are rather homogeneously distributed in the lattice, which is apparently the reason for a synergetic effect on the redox potentials, in contrast to LiFe0.5Mn0.5PO4 samples obtained via hydrothermal routes. After a typical carbon-coating process in a reducing atmosphere (Ar/H2), these LiFe0.5Mn0.5PO4 nanoplatelets undergo a rearrangement of their cations into Mn-rich and Fe-rich domains. Only after such cation rearrangement (via segregation) in the nanocrystals, the redox processes evolved at two distinct potentials, corresponding to the standard Fe2+/Fe3+ and Mn2+/Mn3+ redox centers. Our experimental findings provide new insight into mixed-cation olivine structures in which the degree of cations mixing in the olivine lattice directly influences the redox potentials, which in turn determine their charge/discharge characteristics

Role of acid-base equilibria in the size, shape, and phase control of cesium lead bromide nanocrystals

A binary ligand system composed of aliphatic carboxylic acids and primary amines of various chain lengths is commonly employed in diverse synthesis methods for CsPbBr3 nanocrystals (NCs). In this work, we have carried out a systematic study examining how the concentration of ligands (oleylamine and oleic acid) and the resulting acidity (or basicity) affects the hot injection synthesis of CsPbBr3 NCs. We devise a general synthesis scheme for cesium lead bromide NCs which allows control over size, size distribution, shape, and phase (CsPbBr3 or Cs4PbBr6) by combining key insights on the acid base interactions that rule this ligand system. Furthermore, our findings shed light upon the solubility of PbBr2 in this binary ligand system, and plausible mechanisms are suggested in order to understand the ligand-mediated phase control and structural stability of CsPbBr3 NCs

Coating evaporated MAPI thin films with organic molecules: improved stability at high temperature and implementation in high-efficiency solar cells

Methylammonium lead iodide (MAPI) has proven to be an exceptional light-absorber for single-junction thin-film solar cells. Nonetheless, degradation induced by environmental agents (air, moisture, heat) limits the stability of this hybrid perovskite. Here, we demonstrate that coating evaporated MAPI thin films with different hydrophobic molecules leads to a significant improvement in their stability. We especially investigated the degradation of MAPI and the subsequent formation of PbI2 at 150 °C by in situ XRD analysis and showed that this transformation is remarkably slowed down in films coated with trioctyl phosphine oxide and tridodecyl methylammonium iodide. This enhances the processability of such films, which is an important aspect for the fabrication of thin-film devices. Eventually, we demonstrate that such protected films can be implemented in single-junction n−i−p solar cells without any loss in the device efficiency

Extremely large extinction efficiency and field enhancement in terahertz resonant dipole nanoantennas

The distinctive ability of nanometallic structures to manipulate light at the nanoscale has recently promoted their use for a spectacular set of applications in a wide range of areas of research including artificial optical materials, nano-imaging, biosensing, and nonlinear optics. Here we transfer this concept to the terahertz spectral region, demonstrating a metal nanostructure in shape of a dipole nanoantenna, which can efficiently resonate at terahertz frequencies, showing an effective cross section >100 times larger than its geometrical area, and a field enhancement factor of ~280, confined on a lateral section of ~λ/1,000. These results lead to immediate applications in terahertz artificial materials exhibiting giant dichroism, suggest the use of dipole nanoantennas in nanostructure-based terahertz metamaterials, and pave the way for nanoantenna-enhanced terahertz few-molecule spectroscopy and localized terahertz nonlinear optics

Reversible Emission Tunability from 2D‐Layered Perovskites with Conjugated Organic Cations

The structural flexibility of 2D‐layered halide perovskites provides unprecedented opportunities for tuning their optical properties. For example, lattice distortions facilitate white emission that stems from self‐trapped excitons or defects, and organic cations and halides determine structural stability and emission range. Herein, the optical properties of a set of single‐layer thiophene‐based 2D lead bromide platelets are investigated. Blue‐ and white‐emitting materials based on the choice of thiophene cation and HBr concentration in the synthesis and reversible white to blue color switching by sequential washing and precursor exposure of the fabricated samples are obtained. The photophysical and structural studies indicate that the key to color switching is the formation and suppression of self‐trapped excitons by the supply and removal of cations and halides in acetone. The range of emission color from these materials is extended to red by efficient Mn doping that leads to an additional strong emission peak centered at 620 nm. The findings stimulate the development of color‐tunable and switchable light emitters based on a single material