Orient-Occident dans la bande dessinée

Dans les études sur le discours géopolitique véhiculé par les médias (popular geopolitics), beaucoup de textes ont été analysés pour comprendre l’espace politique et les relations de pouvoir. En utilisant la même méthode, c’est-à-dire l’analyse de contenu (Rose, 2016), cet essai se concentrera sur des œuvres de bandes dessinées réalisées principalement par des auteurs musulmans, dont les mots et les images seront analysés pour mieux comprendre le milieu culturel et les différentes visions du monde : la dichotomie Occident-Orient, l’hybridation entre cultures et les problématiques d’une société multiculturelle telles que l’antisémitisme. Pour ce faire, deux types de bandes dessinées seront étudiés : d’abord, des autobiographies dans lesquelles la vie quotidienne au Moyen-Orient est présentée à la première personne et, ensuite, des histoires qui narrent les aventures de superhéros dont l’identité est très spécifique, notamment musulmane. Les objets analysés, à première vue, peuvent sembler des produits banals de divertissement. En réalité, ils fournissent des informations sur les caractéristiques de certaines régions intéressantes pour la géographie et décrivent des imaginaires précis. Ils offrent aussi bien une perception particulière de l’espace politique et du milieu par les protagonistes (que ce soient des individus ou des groupes) que le degré de participation ou de détachement de l’auteur par rapport à la réalité géographique relatée.In the essays about geopolitical discourse conveyed by the media (popular geopolitics) many texts have been analyzed to understand political space and power relations. Applying the same method, this article focuses on a set of comics mostly by Muslim authors, whose words and images are analyzed to better understand the cultural environment and the different worldviews of their authors: West-East dichotomy, the hybridization between cultures and the problems of multicultural societies such as antisemitism and islamophobia. In order to do this, two types of comics are used: first, autobiographies in which daily life in the Middle East is narrated in the first person and, secondly, adventures of superheroes with a Muslim identity. Apparently, comics may seem like ordinary entertainment products. On the contrary they also provide information on the characteristics of certain regions and denote precise geographical imaginaries. They also offer a particular perception of the political space as seen by the protagonists (whether individuals or groups) and the degree of participation or detachment of the author from the represented reality

Energy analysis of different municipal sewage sludge-derived biogas upgrading techniques

Biomass-derived energy sources are rising their importance since both public opinion and legislation are currently calling for a sustainable development. Biogas is an energy source which can come from municipal sewage sludge digestion thus coupling the advantages of being a renewable energy source and of allowing a smart waste reutilization. In order to fully exploit the biogas potential as vehicle fuel or natural gas substitute, biogas itself must be treated in order to obtain biomethane. Biogas upgrading, i.e., the treatment for CO2 removal, can be performed by several techniques, each one characterised by a different energy demand. Since no clear guidelines are given in literature for choosing among different biogas upgrading processes, this work presents a quantitative analysis, from an energy view point, of water scrubbing, MEA (monoethanolamine) scrubbing, and MDEA (methyldiethanolamine) scrubbing when applied to obtain biomethane from municipal sewage sludge-derived biogas. Heat and electrical power consumptions of each of the above mentioned processes have been obtained by means of process simulation with commercial packages (such as Aspen Plus®). The aim of the work is the energetic comparison among these different techniques. Such a comparison can help in assessing the impact of the biogas purification step on the energy balance of the whole biomethane production process

GW190521 as a dynamical capture of two nonspinning black holes

Gravitational waves from $\sim 90$ black holes binary systems have currently been detected by the LIGO and Virgo experiments, and their progenitors' properties inferred. This allowed the scientific community to draw conclusions on the formation channels of black holes in binaries, informing population models and -- at times -- defying our understanding of black hole astrophysics. The most challenging event detected so far is the short duration gravitational-wave transient GW190521. We analyze this signal under the hypothesis that it was generated by the merger of two nonspinning black holes on hyperbolic orbits. The best configuration matching the data corresponds to two black holes of source frame masses of $81^{+62}_{-25}M_\odot$ and $52^{+32}_{-32}M_\odot$ undergoing two encounters and then merging into an intermediate-mass black hole. We find that the hyperbolic merger hypothesis is favored with respect to a quasi-circular merger with precessing spins with Bayes' factors larger than 4300 to 1, although this number will be reduced by the currently uncertain prior odds. Our results suggest that GW190521 might be the first gravitational-wave detection from the dynamical capture of two stellar-mass nonspinning black holes.Comment: Version accepted for publicatio