Toward an anisotropic atom-atom model for the crystalline phases of the molecular S8 compound

We analize two anisotropic atom-atom models used to describe the crystalline alpha,beta and gamma phases of S8 crystals, the most stable compound of elemental sulfur in solid phases, at ambient pressure and T<=400 K. The calculations are performed via a series of classical molecular dynamics (MD) simulations, with flexible molecular models and using a constant pressure-constant temperature algorithm for the numerical simulations. All intramolecular modes that mix with lattice modes, and are therefore relevant on the onset of structural phase transitions, are taken into account. Comparisons with experimental data and previous results obtained with an isotropic atom-atom molecular model are also performed.Comment: Major changes, new simulations and figures added, revtex4, to appear in J. Chem. Phy

The impact of social pressure on tax compliance: A field experiment

We study the effect of social pressure on tax compliance, focusing on the compliance of shop sellers to the legal obligation of releasing tax receipts for each sale. We carry out a field experiment on bakeries in Italy, where a strong gap exists between the legal obligation and the actual behavior of sellers. Social pressure is manipulated by means of an explicit request for a receipt when not released. We employ an innovative approach to the identification of the treatment effect. We find that a single request for a receipt causes a 17 per cent rise in the probability of a receipt being released for a sale occurring shortly thereafter, causing on average more than two receipts to be released. We also find strong evidence of persistence in compliance decisions. (C) 2016 Elsevier Inc. All rights reserved

1D-Disordered Conductor with Loops Immersed in a Magnetic Field

We investigate the conductance of a 1-D disordered conducting loop with two contacts, immersed in a magnetic flux. We show the appearance in this model of the Al'tshuler-Aronov-Spivak behaviour. We also investigate the case of a chain of loops distributed with finite density: in this case we show that the interference effects due to the presence of the loops can lead to the delocalization of the wave function.Comment: 8 pages; LaTeX; IFUM 463/FT; to appear in Phys. Lett.

Taranto: a flickering landscape of illusory progress, vanished hope, and invisible beauty

The article investigates the difficult and controversial landscape of Taranto, a recently industrialised city of southern Italy, which in the last 70 years has undergone dramatic changes. We analyse what the landscape is in material, cultural, and symbolic terms, what it does, and what it means in and for Taranto. In particular, by analysing bibliographic, cartographic, and audiovisual sources, we trace the evolution of contemporary Taranto, indicating the main factors which enabled its material transformation during the second half of the twentieth century. Then, we reflect on how the landscape has been shaped in different times and at different scales through dominant narratives and counter-narratives. Finally, we identify specific elements of Taranto's landscape and their symbolic meaning. The study offers a paradigmatic case of a flickering landscape, modified by political forces and cultural constructs

Simulation of CO2 Capture by MEA Scrubbing with a Rate-Based Model

n/

Linear Theory of Electron-Plasma Waves at Arbitrary Collisionality

The dynamics of electron-plasma waves are described at arbitrary collisionality by considering the full Coulomb collision operator. The description is based on a Hermite-Laguerre decomposition of the velocity dependence of the electron distribution function. The damping rate, frequency, and eigenmode spectrum of electron-plasma waves are found as functions of the collision frequency and wavelength. A comparison is made between the collisionless Landau damping limit, the Lenard-Bernstein and Dougherty collision operators, and the electron-ion collision operator, finding large deviations in the damping rates and eigenmode spectra. A purely damped entropy mode, characteristic of a plasma where pitch-angle scattering effects are dominant with respect to collisionless effects, is shown to emerge numerically, and its dispersion relation is analytically derived. It is shown that such a mode is absent when simplified collision operators are used, and that like-particle collisions strongly influence the damping rate of the entropy mode.Comment: 23 pages, 10 figures, accepted for publication on Journal of Plasma Physic

Octonic Electrodynamics

In this paper we present eight-component values "octons", generating associative noncommutative algebra. It is shown that the electromagnetic field in a vacuum can be described by a generalized octonic equation, which leads both to the wave equations for potentials and fields and to the system of Maxwell's equations. The octonic algebra allows one to perform compact combined calculations simultaneously with scalars, vectors, pseudoscalars and pseudovectors. Examples of such calculations are demonstrated by deriving the relations for energy, momentum and Lorentz invariants of the electromagnetic field. The generalized octonic equation for electromagnetic field in a matter is formulated.Comment: 12 pages, 1 figur