De l’ombre à la lumière : la marginalité ambiguë des périphéries urbaines

L’objectif de cet article est de réfléchir aux périphéries des ethnologues urbains à travers l’analyse et la prise en compte des contextes urbains locaux dans la production des savoirs. J’envisage de questionner les périphéries des ethnologues urbains ; tout d’abord du point de vue terminologique, en tentant de mettre en évidence toute l’ambiguïté, dans le temps et dans l’espace, que recouvre l’usage des notions comme celles de marge, de centre et périphérie ; dans un second temps, à partir des questionnements méthodologiques, en évoquant, à travers un tour de France entrepris par les membres de l’association AnthropoVilles, la diversité des travaux in situ des ethnologues urbains ; enfin, par une réflexion empirique, fondée sur mon dernier terrain ethnographique, dans le Nord-Pas-de-Calais

Thermal Expansion in 3d-Metal Prussian Blue Analogs - A Survey Study

We present a comprehensive study of the structural properties and the thermal expansion behavior of 17 different Prussian Blue Analogs (PBAs) with compositions MII3[(M')III(CN)6]2.nH2O and MII2[FeII(CN)6].nH2O, where MII = Mn, Fe, Co, Ni, Cu and Zn, (M')III = Co, Fe and n is the number of water molecules, which range from 5 to 18 for these compounds. The PBAs were synthesized via standard chemical precipitation methods, and temperature-dependent X-ray diffraction studies were performed in the temperature range between -150oC (123 K) and room-temperature. The vast majority of the studied PBAs were found to crystallize in cubic structures of space groups, and . The temperature dependence of the lattice parameters was taken to compute an average coefficient of linear thermal expansion in the studied temperature range. Of the 17 compounds, 9 display negative values for the average coefficient of linear thermal expansion, which can be as large as 39.7 x 10-6 K-1 for Co3[Co(CN)6]2.12H2O. All of the MII3[CoIII(CN)6]2.nH2O compounds show negative thermal expansion behavior, which correlates with the Irving-Williams series for metal complex stability. The thermal expansion behavior for the PBAs of the MII3[FeIII(CN)6]2.nH2O family are found to switch between positive (for M = Mn, Co, Ni) and negative (M = Cu, Zn) behavior, depending on the choice of the metal cation (M). On the other hand, all of the MII2[FeII(CN)6].nH2O compounds show positive thermal expansion behavior.Comment: Submitted, 32 pages, 3 tables, 10 figure

Les artistes de Belleville : valeur et faire-valoir d’un quartier de Paris à leurs dépens ?

Recent studies have highlighted the role of artists in the social and urban evolution of certain neighbourhood of big cities : artists are often considered to be the instigators or even the main actors of the renewal of these areas which were previously mostly working-class districts.Artists deciding to move to Belleville, a former working-class area in north-east Paris, have progressively changed the face of the neighbourhood. Architecturally they have participated in the renovation of numerous run down industrial buildings, sometimes with the help of local associations and then the local government. Economically, artists established in the former boutiques of artisans have sometimes led to the transformation of the commercial landscape of certain streets in the neighbourhood. Finally, from a sociological point of view, the presence of artists has promoted the district through artistic attractions and the organisation of cultural events, thus contributing to the transformation of the local fabric and encouraging a new wealthier population to settle in the area. This local role, promoted by the numerous artistic associations in Belleville, is also supported by the municipality of Paris as it seeks an additional way to put the finishing touches to its policy of urban renewal in the working class neighbourhoods. The artistic associations have been instrumental in both the urban and social renewal ; nevertheless they are often forgotten in artistic and cultural politics. The artists of Belleville therefore wonder what is at stake in this new urban role which calls into question their status as creators and their artistic identity. The aim of this paper is to clarify the implications of being an artist in Belleville nowadays and the ways in which they have participated, actively or passively, in the evolution and transformation of the neighbourhood