Microstructure and chemical composition of Roman orichalcum coins emitted after the monetary reform of Augustus (23 B.C.)

A collection of ancient Roman orichalcum coins, i.e., a copper-zinc alloy, minted under the reigns from Caesar to Domitianus, have been characterised using scanning electron microscopy (SEM-EDS) and electron microprobe analysis (EMPA). We studied, for the first time, coins emitted by Romans after the reforms of Augustus (23 B.C.) and Nero (63-64 A.D). These coins, consisting of asses, sestertii, dupondii and semisses, were analysed using non- and invasive analyses, aiming to explore microstructure, corrosive process and to acquire quantitative chemical analysis. The results revealed that the coins are characterized by porous external layers, which are affected by dezincification and decuprification processes. As pictured by the X-ray maps, the elemental distribution of Cu and Zn shows patterns of depletion that in some cases penetrate in deep up to 1 mm. The composition of the un-corroded nucleus is a Cu-Zn alloy containing up to 30% of Zn, typical of coins produced via cementation process

Site effects at the Campi Flegrei,preliminary results

The Campi Flegrei caldera is a complex structure with a high population density, located west of the city of Naples. In addition of being an active volcano it is characterized by a high seismic hazard due to both Appennines regional earthquakes and to local earthquakes occurring during the bradyseismic crises. These unrest phenomena are characterized by slow ground vertical movements, particularly active in the central part of the caldera, and by a high number of low-magnitude earthquakes. In this context, the determination of the site transfer functions of the area has a strong relevance for the Civil Defense aimed to determine the hazard of the area. We have calculated the site transfer function with different techniques (H/V and Generalized Inversion technique) and have collected data on the local geology with the aim of correlating the site transfer functions with lithology and topography. This analysis has been performed on three areas: the Astroni crater, the Camaldoli hill and the Agnano plain. A future development will be to extend this analysis to the whole Campi Flegrei area

Somma Vesuvius: the Volcano and the Observatory

The present guidebook was prepared for the fieldtrip during the Kick off meeting of the project titled “Strategies and tools for Real Time Earthquake RisK ReducTion” (REAKT). It reports information on the geology of the Somma-Vesuvius volcanic area and illustrates the sites visited during the field excursion. The guide mostly benefited of contributions coming from some previous guidebooks (Cioni et al., 1995; Orsi et al., 1998); it also includes some interesting results available in the main and most recent literature. The fieldtrip will be devoted to illustrating i) the major morphological and structural features of the Somma-Vesuvius volcano, and ii) the deposits of the eruptions and their impact on the territory. The trip will end with the tour of the Osservatorio Vesuviano edifice that preserves the memory of the oldest volcanological observatory in the world and hosts a museum and two scientific exibitions

Role of phase nanosegregation in the photoluminescence spectra of halide perovskites

The study of MAPbI3 phase transitions based on temperature-dependent optical spectroscopy has recently gained a huge attention. Photoluminescence (PL) investigations of the tetragonal-orthorhombic transition suggest that tetragonal nanodomains are present below the transition temperature and signatures associated with tetragonal segregations are observed. We have studied the impact of phase nanosegregation across the orthorhombic-tetragonal phase transition of MAPbI3 on the system's properties employing a tight binding (TB) approach. The particle swarm optimization has been used to obtain a consistent set of TB parameters, where the target properties of the system have been derived by first-principles calculations. The theoretical results have been compared with the measured PL spectra for a temperature range going from 10 to 100 K. Our model effectively captures the carriers' localization phenomenon induced by the presence of residual tetragonal nanodomains and demonstrates that the assumption of phase nanosegregation can explain the low-energy features in the PL spectra of MAPbI3

Comment on: ‘‘The dark nature of Somma-Vesuvius volcano:Evidence from the 3.5 ka BP Avellino eruption’’ by Milia A.Raspini A., Torrente M.M.,

We present here some criticism to the scientific content of the paper of Milia et al. [2007. The dark nature of Somma-Vesuvius volcano: evidence from the 3.5 ka B.P. Avellino eruption. Quaternary International, 173–174, 57–66] published in Quaternary International. Milia et al. (2007) interpreted seismic lines in the Gulf of Naples (southern Italy), and inferred the presence of deposits from a large debris avalanche which occurred just before the Avellino eruption of Somma-Vesuvius volcano. The authors supported their seismic profile interpretation with on-land stratigraphies and logs. However, we present here different on-land data that demonstrate the inconsistency of the occurrence of any debris avalanche before or after the Avellino eruption, and we provide also an alternative interpretation for the observed seismic facies offshore of Somma-Vesuvius

Caldera dei Campi Flegrei: potenzialità di un SIT per valutazioni di pericolosità vulcanica

La caldera dei Campi Flegrei è un’area vulcanica attiva, attualmente in stato di quiescenza dal 1538 d.C., soggetta ad un elevato rischio vulcanico per la presenza di numerosi centri abitati e per l’immediata vicinanza alla città di Napoli. Le due maggiori eruzioni esplosive dei Campi Flegrei risalgono a circa 39 ka e 15 ka ed hanno prodotto l’Ignimbrite Campana ed il Tufo Giallo Napoletano, i depositi più noti dell’area napoletana, distribuiti su aree vastissime. Al presente, il sistema magmatico risulta essere ancora attivo, come testimoniato dall’eruzione di Monte Nuovo nel 1538, dai recenti episodi bradisismici e dall’attività fumarolica e idrotermale. Al fine di rendere disponibile alla comunità scientifica ed agli enti preposti alla gestione delle emergenze un efficace strumento tecnologico, a supporto delle valutazioni di pericolosità vulcanica, è stato implementato un sistema informativo territoriale strutturato sulla base di un database in cui sono state raccolte e organizzate tutte le informazioni vulcanologiche e territoriali sull’area. In questo lavoro, attingendo al patrimonio informativo disponibile, sono state effettuate analisi di dettaglio finalizzate alla produzione di nuovi tematismi da utilizzare per la definizione degli scenari di evento, attraverso i quali simulare le conseguenze di un evento vulcanico, di caratteristiche prefissate, che si verifichi nell’area dei Campi Flegrei