Search results for "Beni culturali"

The use of gadolinium for ESR dosimetry

2010

The application of gadolinium to sensitize Electron Spin Resonance (ESR) dosimeters is reviewed. This nucleus is chosen because it has very good features in interacting with ionizing radiations. In particular, it has a very high capture cross section for thermal neutrons which favors the interactions of these particles within the detector; moreover, the charged secondary particles released after neutron interactions (mainly Auger and internal conversion electrons) are able to release their energy close the gadolinium site and, therefore, inside the sensitive volume of the detector. Consequently, the addition of gadolinium inside ESR dosimeters produces a significant enhancement of thermal n…

Indagini ESR su legni moderni e antichi.

2007

ESR spectroscopy for analyzing the spatial distribution of free radicals in ammonium tartrate

2013

Revisiting the role of top-down and bottom-up controls in stabilisation of nutrient-rich plankton communities

2019

Understanding the conditions for successful control of phytoplankton by zooplankton in eutrophic ecosystems is a highly important research area with a wide implementation of mathematical modelling. Theoretical models generally predict destabilisation of food webs in eutrophic environments with large-amplitude oscillations of population densities which would eventually result in species extinction. On the other hand, these theoretical predic- tions are often at odds with ecological observations demonstrating stable dynamics even for a high nutrient load. This apparent discrepancy is known in the literature as Rosen- zweig’s “paradox of enrichment”. Recent theoretical works emphasize a crucia…

Long-term ecology of investors in a financial market

2018

AbstractThe cornerstone of modern finance is the efficient market hypothesis. Under this hypothesis all information available about a financial asset is immediately incorporated into its price dynamics by fully rational investors. In contrast to this hypothesis many studies have pointed out behavioral biases in investors. Recently it has become possible to access databases that track the trading decisions of investors. Studies of such databases have shown that investors acting in a financial market are highly heterogeneous among them, and that heterogeneity is a common characteristic of many financial markets. The article describes an empirical study of the daily trading decisions of all Fi…

Econofisica: il contributo dei fisici allo studio dei sistemi economici

2005

Do firms share the same functional form of their growth rate distribution? A statistical test

2014

We introduce a new statistical test of the hypothesis that a balanced panel of firms have the same growth rate distribution or, more generally, that they share the same functional form of growth rate distribution. We applied the test to European Union and US publicly quoted manufacturing firms data, considering functional forms belonging to the Subbotin family of distributions. While our hypotheses are rejected for the vast majority of sets at the sector level, we cannot rejected them at the subsector level, indicating that homogenous panels of firms could be described by a common functional form of growth rate distribution.

Il Cielo in una Stanza

2021

Il testo, nato nell'ambito del progetto "Noi come voi, mission impossible?" patrocinato dall'Università degli Studi di Palermo, è un racconto illustrato concepito come una guida per accompagnare bambini e ragazzi nella visita dei tesori artistici della città. Al centro del percorso è la "stanza delle meraviglie", che è stata recentemente scoperta in un edificio ubicato fra il Palazzo dei Normanni e il mercato di Ballarò." La scommessa", scrive Giuseppe Zanniello, "è stata quella di ritenere che i bambini delle scuole primarie potessero migliorare la propria autostima riflettendo sui tesori artistici che sono fisicamente presenti accanto alla loro scuola e alle loro abitazioni, ma ai quali e…

New insight about the mural painting branches of Roman baths in Reggio Calabria

2023

The Roman baths in Reggio Calabria (Italy) provides many information regarding both engineering and technology for this type of buildings. A small treasure of three survived mural paintings enclose information about the artistic style and the ancient luxury of the baths. In order to get light on the executive technique and conservation state we performed the investigation of these paintings by following a non invasive approach composed of multispectral imaging and spectroscopic analysis. By so doing we determined the pigment palette and the distribution of some pigments allowing us to make some hypothesis about the executive technique and provide a basis for a future virtual restoration of …

Monte Carlo simulation of energy absorbed in phenolic ESR dosimeters added with gadolinium exposed to thermal, epithermal and fast neutrons

2017

Abstract In this work analyses of the energy released per unit mass in phenolic compound exposed to neutron beams were performed with the aim of predicting the increase in dose achievable by addition of gadolinium (Gd) inside the pellets. In particular, Monte Carlo (MC) simulations were carried out for IRGANOX® 1076 phenolic compound irradiated with neutron beams with different energy spectra at various depths inside a water phantom. The addition of gadolinium increases sensitivity of phenolic ESR (electron spin resonance) dosimeters to neutrons thanks to the high gadolinium cross section for neutron capture and to the large number of secondary particles (mainly Auger and internal conversio…