89 research outputs found
Bandier (N.), Gilbert (F.), Micoud (A.), 1980, La Parole de la ville. Lyon, PUL
No full textBailly Antoine S.Bailly Antoine S. Bandier (N.), Gilbert (F.), Micoud (A.), 1980, La Parole de la ville. Lyon, PUL. In: L'Espace géographique, tome 12, n°4, 1983. p. 316
Le lieu comme figure exemplaire de l’ordre du territoire qui vient
No full textFrom two themes, that of the "local figure" and that of "utopia that takes place", the author considers the locus as it proceeds from an effort to make it original. Using two concrete examples, in the town and in the countryside, that use the figure of "etabli" (according to the meaning offered by the maoiste French movement), he investigates local "alternative" initiatives. Finally, he asserts it is possible to read it in the theoretic foundations of the legitimacy of new territories.À partir de deux motifs, celui de la « figure locale » et celui de « l’utopie qui a lieu », l’auteur saisit le lieu en tant qu’il procède d’un effort pour le construire comme inédit. S’appuyant sur deux exemples concrets qu’il lui a été donné d’étudier, à la ville et à la campagne, et qui tous les deux mobilisent la figure de l’ « établi », il soutient la thèse selon laquelle, dans les initiatives « locales » se donnant à voir comme alternatives, il serait possible de déceler les assises théoriques de la légitimité in statu nascendi des nouveaux territoires en gestation.Micoud André. Le lieu comme figure exemplaire de l’ordre du territoire qui vient. In: Communications, 87, 2010. Autour du lieu, sous la direction de Aline Brochot et Martin de la Soudière. pp. 109-119
Patrimonialiser le vivant
No full textIntrigued by the new requirements to "save the nature", "preserve the environment", "save the natural patrimony of humanity", or also to "maintain biodiversity", the author wonders where this new concern for patrimonializing the living comes from. As if it weren't a part of life to perpetuate itself by its own reproduction. The thesis he develops is that rather than a concern about the future of life, it truly is a symptom caused by the project of mastering it in the future. The patrimonializing of the living would then be a process isolating all factors by which life reproduces itself, to master it as a resource without any influence by the period in evolution or the environment.Face aux exigences nouvelles demandant de "conserver la nature", de "préserver l'environnement", de "sauvegarder le patrimoine naturel de l'humanité" ou encore de "maintenir la biodiversité", l'auteur se demande ce que signifie le souci actuel pour la perpétuation du vivant. Comme s'il n'était pas dans l'essence même de la vie, par sa transmission, que de se persévérer dans son être ? La thèse qu 'il propose consiste à soutenir que plus qu 'un souci sur l'avenir de la vie, il s 'agit d'un symptôme accompagnant le projet de sa maîtrise future. La patrimonialisation du vivant serait donc ce processus qui, pour en faire une ressource, isole les facteurs par lesquels la vie se perpétue pour fabriquer des êtres vivants à la fois hybrides quant au temps de l'évolution et dissociés de leur environnement.Micoud André. Patrimonialiser le vivant. In: Espaces Temps, 74-75, 2000. Transmettre aujourd'hui. Retour vers le futur, sous la direction de Philippe Dujardin, Patrick Garcia et Bénédicte Goussault. pp. 66-77
Redukce kyslíku v elektrolytu obsahujícím hydroxid a borohydrid sodný
No full textThe Principle of double layer on carbon electrode has been used for the design of new components, called electrochemical supercapatitors
Parution du bulletin n° 33 de la SFHSH
No full textPour l'histoire des sciences de l'homme Bulletin n° 33, été 2009. Editorial par D. Becquemont, J.-P. Bouilloud, D. Ottavi, M.-F. Piguet 3 TEXTES Recherches et réflexions La comptabilité morale : une véritable science des hommes criminels ?, B. Vanhulle 8 Pourquoi la technique n’est pas une science appliquée. Réflexions sur Canguilhem et Kapp, G. Chamayou 16 La sociologie comme science appliquée. Retour sur une expérience, Le cas du CRESAL, Saint-Etienne, 1958-2007, A. Micoud 24 Notes de lectu..
Impact of Transition Metals and Electrocatalyst Layer Thickness on the Pt-Based Cathodes of Proton Exchange Membrane Fuel Cells – Do Multimetallic Electrocatalysts Necessarily Yield an Improved Performance?
No full textThe interplay between i) cathodic electrocatalytic layer (EC layer) features of proton exchange membrane fuel cell (PEMFC), focusing on the oxygen reduction reaction (ORR) electrocatalyst (EC) and the Pt loading; and ii) the PEMFC performance and durability is evaluated. An innovative hierarchical “core–shell” carbon nitride multimetallic ORR electrocatalyst (“PtCuNi/C” H-EC) is compared with a conventional Pt/C benchmark. The various contributions to PEMFC performance at beginning of test (BOT) are isolated and correlated to the physicochemical features of the ORR EC and the cathodic EC layer. The PEMFC durability is investigated extensively via accelerated stress tests (ASTs) mimicking long-term operation. Particular attention is dedicated to determine how ageing affects: i) PEMFC cell voltage; and ii) the cathode electrochemically active surface area (ECSA). “Post-mortem” studies are carried out to probe how ageing influences the cathodic EC layer features, including: i) chemical composition; ii) elements distribution; iii) EC morphology; and iv) structure and crystal size of the Pt-based metal nanoparticles bearing the active sites. Integrating the experimental results allows to identify both the positive and the detrimental effects triggered by the introduction of transition metals (TMs) in the ORR EC on the factors modulating PEMFC performance and long-term operation
L’expérience récente des Comités de quartier à Saint-Étienne
No full textDéveloppés dans le double contexte, national, d’un discours consensuel sur le nécessaire renouveau de la démocratie locale et régional, d’une victoire d’une liste de gauche aux élections municipales, l’expérience des comités de quartier permet de tester, sur le cas de la ville de Saint-Étienne, le contenu et le rôle de ces nouvelles formes de groupement établis sur une base résidentielle. L’étude distingue trois types de comités définis principalement par les modes de rapport à la population qu’ils sont censés représenter ainsi que par leurs codes implicites de fonctionnement.En conclusion, les auteurs s’interrogent sur les modifications réelles introduites par l’existence de ces comités dans le système traditionnel de gestion-représentation des populations locales.Citizen groups have sprung up recently in the city of Saint-Etienne in a context that is characterized by two main features: (1) the new political will at the national level to stimulate local and regional democracy and (2) the victory of the left-wing parties in recent municipal elections. This article attempts to analyse the content and role of these new neighbourhood organizations. Three types of committees are defined in function of the types of relationships that they have worked out with the people that they are supposed to represent.The author examines the nature of the changes in traditional municipal politics that these groupes have been able to bring about.Desarrollados en un doble contexto, nacional, como un discurso consensual sobre la renovación necesaria de la democracia local, y regional, como una victoria de una lista de izquierda en las elecciones municipales, la experiencia de los comités de barrio permite evaluar, a partir del caso de la ciudad de Saint-Étienne, el contenido y el rol de estas nuevas formas de agrupación sobre una base residencial. el estudio distingue tres tipos de comités, definidos principalmente por los modos de relación a la población que buscan representar, así como por sus códigos implícitos de funcionamiento. Los autores se interrogan en conclusión sobre las modificaciones reales introducidas por la existencia de estos comités en el sistema tradicional de gestion-representación de las poblaciones locales
Engineering Proton Exchange Membrane Fuel Cell (PEMFC) catalysts and electrodes
No full textInternational audienceProton exchange membrane fuel cells (PEMFCs) now start to witness industrial deployment. However, the durability of the cathode catalyst and electrode must still be improved to meet the requirements of heavy-duty mobility. The cathode catalyst can be improved by using more corrosion-resistant carbon support, e.g. based on graphitized carbon black [1], and by protecting the Pt-based nanoparticles with a carbon cap [2].In the former case, the standard procedure to prepare PEMFC membrane electrode assemblies (MEA) (mixing the high surface area carbon black-supported platinum nanoparticles with appropriate ionomer in an ink, so to form the active layers of the cathode and anode after proper mixing and deposition [3, 4]) must be adapted in terms of ionomer-to-carbon ratio and ink mixing procedure [5]. In the latter one, engineering of the carbon cap requires a particular activation procedure [2]. In addition, the usual “randomly-organized” structure of the PEMFC MEA, optimized via decades of research [3, 4], can possibly be challenged by using more organized materials, compatible with fast mass-transport of reactant and products [6].All these aspects will be addressed in this contribution.Acknowledgements: The PEMFC95 project was funded by France's "Programme d’Investissements d’Avenir" operated by the French National Research Agency (grant ANR-22-PEHY-0005)References[1] L. Castanheira, W.O. Silva, F.H.B. Lima, A. Crisci, L. Dubau, F. Maillard, Carbon corrosion in proton-exchange membrane fuel cells: Effect of the carbon structure, the degradation protocol, and the gas atmosphere, ACS Catal., 5 (2015) 2184-2194.[2] Q. Labarde, A. Godoy, L. Dubau, F. Micoud, M. Chatenet, Carbon-capped PtNi catalysts for the oxygen reduction reaction in acidic environment: A durability study, Small Structures, (2024).[3] M.B. Sassin, Y. Garsany, B.D. Gould, K.E. Swider-Lyons, Fabrication Method for Laboratory-Scale High-Performance Membrane Electrode Assemblies for Fuel Cells, Anal. Chem., 89 (2017) 511-518.[4] S.S. Kocha, Principle of MEA preparation, in: W. Vielstich, A. Lamm, H.A. Gasteiger (Eds.) Handbook of Fuel Cells, Wiley, Chichester, 2003, pp. 538-565.[5] C. Lafforgue, P. Toudret, F. Micoud, M. Heitzmann, J.-F. Blachot, M. Chatenet, Manufacturing Of Graphitized Carbon-Supported Platinum Cathodes Of Proton Exchange Membrane Fuel Cell Using The Doctor Blade Process: Microstructure And Performance, J. Electrochem. Soc., (2024).[6] M. Tempelaere, M. Zimmermann, M. Chatenet, 3D-structured electrocatalysts for improved mass-transfer in proton-exchange membrane fuel cell cathodes, Current Opinion in Electrochemistry, 41 (2023) 101353
Engineering Proton Exchange Membrane Fuel Cell (PEMFC) catalysts and electrodes
No full textInternational audienceProton exchange membrane fuel cells (PEMFCs) now start to witness industrial deployment. However, the durability of the cathode catalyst and electrode must still be improved to meet the requirements of heavy-duty mobility. The cathode catalyst can be improved by using more corrosion-resistant carbon support, e.g. based on graphitized carbon black [1], and by protecting the Pt-based nanoparticles with a carbon cap [2].In the former case, the standard procedure to prepare PEMFC membrane electrode assemblies (MEA) (mixing the high surface area carbon black-supported platinum nanoparticles with appropriate ionomer in an ink, so to form the active layers of the cathode and anode after proper mixing and deposition [3, 4]) must be adapted in terms of ionomer-to-carbon ratio and ink mixing procedure [5]. In the latter one, engineering of the carbon cap requires a particular activation procedure [2]. In addition, the usual “randomly-organized” structure of the PEMFC MEA, optimized via decades of research [3, 4], can possibly be challenged by using more organized materials, compatible with fast mass-transport of reactant and products [6].All these aspects will be addressed in this contribution.Acknowledgements: The PEMFC95 project was funded by France's "Programme d’Investissements d’Avenir" operated by the French National Research Agency (grant ANR-22-PEHY-0005)References[1] L. Castanheira, W.O. Silva, F.H.B. Lima, A. Crisci, L. Dubau, F. Maillard, Carbon corrosion in proton-exchange membrane fuel cells: Effect of the carbon structure, the degradation protocol, and the gas atmosphere, ACS Catal., 5 (2015) 2184-2194.[2] Q. Labarde, A. Godoy, L. Dubau, F. Micoud, M. Chatenet, Carbon-capped PtNi catalysts for the oxygen reduction reaction in acidic environment: A durability study, Small Structures, (2024).[3] M.B. Sassin, Y. Garsany, B.D. Gould, K.E. Swider-Lyons, Fabrication Method for Laboratory-Scale High-Performance Membrane Electrode Assemblies for Fuel Cells, Anal. Chem., 89 (2017) 511-518.[4] S.S. Kocha, Principle of MEA preparation, in: W. Vielstich, A. Lamm, H.A. Gasteiger (Eds.) Handbook of Fuel Cells, Wiley, Chichester, 2003, pp. 538-565.[5] C. Lafforgue, P. Toudret, F. Micoud, M. Heitzmann, J.-F. Blachot, M. Chatenet, Manufacturing Of Graphitized Carbon-Supported Platinum Cathodes Of Proton Exchange Membrane Fuel Cell Using The Doctor Blade Process: Microstructure And Performance, J. Electrochem. Soc., (2024).[6] M. Tempelaere, M. Zimmermann, M. Chatenet, 3D-structured electrocatalysts for improved mass-transfer in proton-exchange membrane fuel cell cathodes, Current Opinion in Electrochemistry, 41 (2023) 101353
- …
