The effect of heavy tars (toluene and naphthalene) on the electrochemical performance of an anode-supported SOFC running on bio-syngas

The effect of heavy tar compounds on the performance of a Ni-YSZ anode supported solid oxide fuel cell was investigated. Both toluene and naphthalene were chosen as model compounds and tested separately with a simulated bio-syngas. Notably, the effect of naphthalene is almost negligible with pure H2 feed to the SOFC, whereas a severe degradation is observed when using a bio-syngas with an H2:CO = 1. The tar compound showed to have a remarkable effect on the inhibition of the WGS shift-reaction, possibly also on the CO direct electro-oxidation at the three-phase-boundary. An interaction through adsorption of naphthalene on nickel catalytic and electrocatalytic active sites is a plausible explanation for observed degradation and strong performance loss. Different sites seem to be involved for H2 and CO electro-oxidation and also with regard to catalytic water gas shift reaction. Finally, heavy tars (C>=10) must be regarded as a poison more than a fuel for SOFC applications, contrarily to lighter compounds such benzene or toluene that can directly reformed within the anode electrode. The presence of naphthalene strongly increases the risk of anode re-oxidation in a syngas stream as CO conversion to H2 is inhibited and also CH4 conversion is blocked

P.Herc. 817 and the Augustan Ideology

P.Herc. 817 provides us with the remnants of an anonymous and anepigraphic poem about the capture of Egypt by Octavian in 30 B.C. In the last years, the surviving fragments have been interpreted as containing a critical text against Augustus. However, a correct reading of the text and, especially, a contextualization of the poem in relation to the motives related with the Augustan ideology, allows to truly understand the author's point of view and his positioning towards the princeps. The author depicts the virtues of Octavian and of his soldiers, characterized positively in terms of fides, potentia, etc. Octavian restrains his soldiers from plundering the city of Pelousios, so that his clementia connects him to Julius Caesar directly

Smart Gas Network with Linepack Managing to Increase Biomethane Injection at the Distribution Level

The current situation in Europe calls for the need of urgent measures to find sustainable alternatives to its outer dependence on natural gas. Biomethane injection into the existing gas infrastructure is a fundamental opportunity to be promoted that, however, causes increasing complexities in the management of natural gas grids. At the gas distribution level, the lack of a monitoring system and suitable software for the simulation, management, and verification of gas networks may act as barriers to a widespread diffusion of a biomethane production and injection chain. A transient fluid-dynamic model of the gas network is developed to perform estimations of the natural gas grid capacity in situations of production-consumption mismatch, taking into account the linepack as a gas buffer stock. The model is applied to the gas distribution network of a small urban-rural area. The aim is to assess the role of the linepack in determining the gas network receiving capacity and to test smart management of pressure set-points and injection flow rate to minimize biomethane curtailment. Results show that biomethane unacceptability can be reduced to 10% instead of 27% (obtained when following the DSOs state-of-the-art current procedures), thus highlighting the importance of the implementation of transient simulation software but also underlining the need for smarter control systems, actuators, and data management platforms for a transition to smart digital gas grids

Ovidio al Quirinale

Discussione della mostra Ovidio. Amori, miti e altre storie, curata da Francesca Ghedini e del contributo di Piero Boitani, Storie del divenire: Ovidio e le metamorfosi

La dea e la Bilancia. Elementi di datazione per la Ciris pseudovirgiliana

The paper deals with the complex problem of the datation of the Ciris attributed to Virgil. After a short presentation of the text, the analysis focuses on the astronomical similitude at the end of the poem (vv. 533-537), followed by the struggle between the ciris and the sea-eagle (vv. 538-541=Verg. georg. 1.406-409). A circumstantial reading of the similitude in its astronomical details gives important clues for dating the poem. The author, in fact, does not speak only of the apparent sunset of Scorpion and Orion constellations, but he also mentions at v. 534 a double constellation (duplici... sidere), that is the constellation of Scorpion and of Libra. This constellation was ‘created’ at Rome in the first century AD, as the astronomical and literary sources clearly show. The connection established between the Libra and the horoscope of Augustus made the constellation the seat of Princeps’ catasterism, as already alluded by Virgil (Georg. I 32-35) and showed by a series of literary and iconographic sources. The author of the Ciris clearly knows this tradition: we can therefore assume as terminus post quem for his poem the 31 BC (the same as for the prologue of Georgics). In addition to that, the analysis of verses 87-88 may offer a further clue. The adjective Palaepahia indicates precisely ‘ancient Paphos’: perhaps we have here another encomiastic allusion, since Augustus restored Aphrodite’s temple after the earthquake of 15 BC. As a result, we could not assign in any case the Ciris to the young Virgil

Rostagni, Augusto

Vita, opere e influenza di Augusto Rostagn

Biographie, Werk und Rezeption des Cornelius Gallus: Ein neues Gesamtbild

In this article, the author offers a complete portrait of c. cornelius gallus as a statesman and poet. all testimonia about his life and works are presented and discussed critically. Certain neglected testimonies have been taken into consideration in addition to the standard profiles. the bibliography has been updated. due to the contradictory nature of the sources, preference has been given to pieces of information provided by direct sources such as inscriptions and papyri in terms of reliability. Furthermore, the iconography is listed exhaustively. Finally, the reception the of gallus' works and figure in late antiquity and the medieval forgeries are examined

Parrasio allo Studium Urbis: la praefatio alle silvae di Stazio

In this article the author provides a critical edition, with commentary, of the praefatio to Publius Papinius Statius’ silvae composed by the humanist Aulus Ianus Parrhasius. The text, which is preserved in ms. V D 15 of the Biblioteca Nazionale Vittorio Emanuele III, Naples, dates from the period of Parrhasius’s second stay in Rome (1514-1518). It provides information about the scholars connected with Pomponius Letus and illuminates both Statius’ reception in the Renaissance and teaching practices in the first half of the 16th century

A Statistical Assessment of Blending Hydrogen into Gas Networks

The deployment of low-carbon hydrogen in gas grids comes with strategic benefits in terms of energy system integration and decarbonization. However, hydrogen thermophysical properties substantially differ from natural gas and pose concerns of technical and regulatory nature. The present study investigates the blending of hydrogen into distribution gas networks, focusing on the steady-state fluid dynamic response of the grids and gas quality compliance issues at increasing hydrogen admixture levels. Two blending strategies are analyzed, the first of which involves the supply of NG–H2 blends at the city gate, while the latter addresses the injection of pure hydrogen in internal grid locations. In contrast with traditional case-specific analyses, results are derived from simulations executed over a large number (i.e., one thousand) of synthetic models of gas networks. The responses of the grids are therefore analyzed in a statistical fashion. The results highlight that lower probabilities of violating fluid dynamic and quality restrictions are obtained when hydrogen injection occurs close to or in correspondence with the system city gate. When pure hydrogen is injected in internal grid locations, even very low volumes (1% vol of the total) may determine gas quality violations, while fluid dynamic issues arise only in rare cases of significant hydrogen injection volumes (30% vol of the total)