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The development of high-performance membrane materials for non-aqueous redox flow batteries (NAqRFBs) could unlock a milestone towards widespread commercialization of the technology. Understanding of transport phenomena through membrane materials requires diagnostic tools able to monitor the concentrations of redox active species. While membrane characterization in aqueous media focused the attention of the scientific community, dedicated efforts for non-aqueous electrolytes remain poorly developed. Here, we develop new methodologies to assess critical membrane properties, namely ion exchange capacity and species transport, applied to NAqRFBs. In the first part, we introduce a method based on 19F-NMR to quantify ion exchange capacity of membranes with hydrophobic anions commonly used in non-aqueous systems (e.g., PF6 − and BF4 −). We find a partial utilization of the ion exchange capacity compared to the values reported using traditional aqueous chemistry ions, possibly limiting the performance of NAqRFB systems. In the second part, we study mass transport with a microelectrode placed on the electrolyte tank. We determine TEMPO crossover rates through membranes by using simple calibration curves that relate steady-state currents at the microelectrode with redox active species concentration. Finally, we show the limitations of this approach in concentrated electrolyte systems, which are more representative of industrial flow battery operation.

Wolf Feuerhahn et Olivier Orain : Merci beaucoup a tous deux d’avoir accepte de repondre a nos questions. Vous avez developpe depuis le debut des annees 2000 d’importants programmes de recherche sociologique sur les institutions, les acteurs et les pratiques de la traduction. Votre interet ne portait pas seulement sur les traductions litteraires, mais, et c’est ce point qui nous interesse, la traduction des sciences humaines et sociales (SHS). Pourriez-vous tout d’abord nous rappeler l’intent...

Redox flow batteries (RFBs) are emerging as viable options for grid-scale energy storage, but their elevated costs hamper commercialization. Enhancing the porous carbon electrode performance to improve power density and reduce system costs is an effective strategy toward widespread deployment; however, the porous carbon electrode must satisfy multiple contradictory roles, including providing high surface area, low pressure drop, and facile mass transport, thus motivating electrode engineering efforts. In this work, we systematically explore the non-solvent induced phase separation (NIPS) technique as a platform to synthesize a family of distinct microstructures for use in RFBs. Flow cell studies in commercially relevant redox pairs (i.e., Fe2+/3+, V2+/3+, and V4+/5+) are performed, revealing diverse performance profiles, synthesis-structure-performance relationships, and opportunities for high-power electrode materials. We anticipate that, with further refinement and customization, NIPS electrodes can broadly benefit electrode engineering efforts for electrochemical energy storage and conversion applications.

Spatial and temporal gradients in reactant concentration, influenced by local microstructure and surface properties, govern the performance and durability of various advanced electrochemical systems. The cell and stack performance is typically assessed using traditional electrochemical diagnostics (e.g. polarization curves, electrochemical impedance spectroscopy) and the influence of materials is macroscopically evaluated based on empirical comparison of novel materials with the current state-of-the-art. While this is a valid approach to identify promising candidates, valuable information is lost due to the difficulty of identifying performance-limiting factors. Operando imaging of electrochemical systems, in tandem with complementary electrochemical diagnostics, has been instrumental in the development of advanced polymer electrolyte fuel cells1,2 and, more recently, lithium-ion batteries3,4. Over the past few years, several groups have developed novel imaging and spectroscopic techniques for operando characterization of redox flow batteries, which is the focus of this work. Wong et al. employed fluorescence microscopy and particle velocimetry to image concentration and velocity distributions near the electrode-flow field interface5. Tanaka et al. visualized flow distribution in redox flow batteries with infrared thermography6. Zhao et al. employed in-situ nuclear magnetic resonance to track reaction mechanisms occurring within the electrolyte7. Finally, several groups recently employed X-ray tomographic microscopy to visualize gas pockets within the liquid electrolyte imbibed porous electrode8–10. While these methods have provided important insights, an approach that enables quantitative mapping of species concentrations, in a non-invasive fashion and within an operating cell, has remained elusive. In this presentation, I will discuss our recent efforts to develop neutron radiography as an operando characterization method for non-aqueous redox flow batteries. We leverage the high attenuation of organic materials (i.e., high hydrogen content) in solution and, combined with isotopic labelling, we perform subtractive neutron imaging to quantify the concentration of active species and supporting electrolytes. To demonstrate the potential of this diagnostic tool, we characterize active species concentration distribution within a redox flow cell in a single electrolyte configuration with a non-aqueous electrolyte containing a TEMPO/TEMPO+ redox couple and study the influence of electrode microstructure, membrane type (e.g. porous or dense), and flow field design. To resolve the concentration profiles across the different layers, we employ the in-plane imaging configuration11 and correlate these concentration profiles to cell performance via polarization measurements under different operating conditions. In the final part of the talk, I will discuss our latest experimental campaign in which we investigated the use of energy-selective neutron radiography to deconvolute concentrations of active species and supporting electrodes during operation. References 1 P. Boillat, E. H. Lehmann, P. Trtik and M. Cochet, Curr. Opin. Electrochem., , DOI:https://doi.org/10.1016/j.coelec.2017.07.012. 2 J. Eller, T. Rosén, F. Marone, M. Stampanoni, A. Wokaun and F. N. Büchi, J. Electrochem. Soc., 2011, 158, B963. 3 B. Michalak, H. Sommer, D. Mannes, A. Kaestner, T. Brezesinski and J. Janek, Sci. Rep., 2015, 5, 15627. 4 D. P. Finegan, M. Scheel, J. B. Robinson, B. Tjaden, I. Hunt, T. J. Mason, J. Millichamp, M. Di Michiel, G. J. Offer, G. Hinds, D. J. L. Brett and P. R. Shearing, Nat. Commun., 2015, 6, 6924. 5 A. A. Wong, M. J. Aziz and S. Rubinstein, ECS Trans. , 2017, 77, 153–161. 6 H. Tanaka, Y. Miyafuji, J. Fukushima, T. Tayama, T. Sugita, M. Takezawa and T. Muta, J. Energy Storage, 2018, 19, 67–72. 7 E. W. Zhao, T. Liu, E. Jónsson, J. Lee, I. Temprano, R. B. Jethwa, A. Wang, H. Smith, J. Carretero-González, Q. Song and C. P. Grey, Nature, 2020, 579, 224–228. 8 R. Jervis, L. D. Brown, T. P. Neville, J. Millichamp, D. P. Finegan, T. M. M. Heenan, D. J. L. Brett and P. R. Shearing, J. Phys. D. Appl. Phys., , DOI:10.1088/0022-3727/49/43/434002. 9 F. Tariq, J. Rubio-Garcia, V. Yufit, A. Bertei, B. K. Chakrabarti, A. Kucernak and N. Brandon, Sustain. Energy Fuels, 2018, 2, 2068–2080. 10 K. Köble, L. Eifert, N. Bevilacqua, K. F. Fahy, A. Bazylak and R. Zeis, J. Power Sources, , DOI:10.1016/j.jpowsour.2021.229660. 11 P. Boillat, D. Kramer, B. C. Seyfang, G. Frei, E. Lehmann, G. G. Scherer, A. Wokaun, Y. Ichikawa, Y. Tasaki and K. Shinohara, Electrochem. commun., 2008, 10, 546–550.

Porous carbonaceous electrodes are performance-defining components in redox flow batteries (RFBs), where their properties impact the efficiency, cost, and durability of the system. The overarching challenge is to simultaneously fulfill multiple seemingly contradictory requirements-i.e., high surface area, low pressure drop, and facile mass transport-without sacrificing scalability or manufacturability. Here, non-solvent induced phase separation (NIPS) is proposed as a versatile method to synthesize tunable porous structures suitable for use as RFB electrodes. The variation of the relative concentration of scaffold-forming polyacrylonitrile to pore-forming poly(vinylpyrrolidone) is demonstrated to result in electrodes with distinct microstructure and porosity. Tomographic microscopy, porosimetry, and spectroscopy are used to characterize the 3D structure and surface chemistry. Flow cell studies with two common redox species (i.e., all-vanadium and Fe2+/3+ ) reveal that the novel electrodes can outperform traditional carbon fiber electrodes. It is posited that the bimodal porous structure, with interconnected large (>50 µm) macrovoids in the through-plane direction and smaller (

Redox flow batteries (RFBs) hold promise for efficiently storing and delivering electricity at the grid-scale, offering opportunities to complement and ultimately supplant fossil fuels with sustainable, but variable, energy sources.[1] However, widespread deployment of RFBs is hindered by their prohibitive cost, which depends, at least in part, on reactor performance. Thus, improving cell performance characteristics by targeting critical system components is an effective strategy towards realizing an energy infrastructure powered by renewable resources. In particular, porous carbon electrodes are vital components of RFBs, simultaneously fulfilling multiple crucial roles.[2] The electrode provides surface area for redox reactions to occur, distributes the electrolyte, determines the pressure drop, and cushions the cell during compression; thus, electrode properties are directly coupled with the RFB electrochemical and fluid dynamic performance. However, the commercial materials utilized in advanced flow batteries – typically papers, cloths, or felts – possess low surface area (~0.1 – 10 m2 g-1), poor aqueous wettability, and suboptimal surface chemistry, motivating efforts into electrode engineering. Current approaches for improving the electrode largely focus on post-process modification of pre-existing fiber-bed substrates which, although effective, may ultimately be incremental, as achievable properties are limited by the underlying material. While findings from prior art have furthered knowledge about the role of electrode interfacial chemistry and microstructure in cell performance, greater paradigm shifts may be necessary to unlock transformative advances and to enable chemistry-specific electrode design. In this talk, I will present three concurrent efforts towards rationally designing electrodes with property sets favorable for RFBs. First, I describe a method of refining the interfacial properties of commercial carbon electrodes through conformal deposition of conductive polymers with nanometric thicknesses, analyzing potential benefits of these coatings towards enhanced performance of iron-based redox couples.[3,4] Second, I discuss a strategy to produce sustainably sourced, elementally diverse, and high surface area electrocatalysts derived from biomass.[5] Findings from this work are coupled with modeling efforts to guide the effective utilization of high surface area electrocatalysts. Lastly, I outline a scalable, bottom-up synthetic method for producing tunable electrode microstructures that achieve pore network configurations inaccessible to classic fibrous electrodes. The fabricated scaffolds offer compelling opportunities as platforms for microstructure-function studies and potentially as performance materials.[6,7] While the focus of these efforts is RFBs, the methods, implications, and techniques for these concepts may ultimately be applicable to a diverse portfolio of convection-driven electrochemical systems that benefit from engineered transport layers. Acknowledgements This work was supported as part of the Joint Center for Energy Storage Research, an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences. CTW acknowledges additional funding from the National Science Foundation Graduate Research Fellowship Program under Grant No. 1122374. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation. References: [1] Dunn et al., Science 2011, 334, 928. [2] Kim et al., J. Mater. Chem. A 2015, 3, 16913. [3] Heydari Gharahcheshmeh & Wan et al., Adv. Mater. Interfaces 2020, 2000855. [4] Gleason, Brushett, Wan, Forner-Cuenca, Heydari Gharahcheshmeh, Ashraf Gandomi, 2020, Provisional Patent U.S. Serial No. 63/050,361 [5] Wan & López Barreiro et al., ACS Sustainable Chem. Eng. 2020, acssuschemeng.0c02427. [6] Forner-Cuenca, Wan, Jacquemond, & Brushett, 2020, Provisional Patent U.S. Serial No. 62/976,601 [7] Wan & Jacquemond et al., Adv. Mat., 2021, in revision

International audience; Translation theory has always been intimately connected to practice. For centuries, it was mostly elaborated by translators and was always prescriptive, that is, aiming at defining the conditions for "good" translating. Actually, while it would be tempting to take the emergence of "descriptive translation studies"-to mention Gideon Toury's (1995) most celebrated contribution to the field-as the birthmark of the study of translation as an autonomous discipline, one could argue that translation studies remain till now dependent on prescription in many ways, as remarks Lawrence Venuti (2000: 4). We find within the field of translation studies a much larger proportion of active translators than, say, the proportion of creative writers within the field of literary studies. All this points to the dependent, subaltern status of the translated text, and-without delving further into the philosophical and ethical implications of this question-provides me with a good starting point. I would like for this contribution to be a reflection on the link between theory and practice in translation, based on my own, three-decade long experience as a translator, a translation editor, and a scholar in translation studies. It has been a very particular experience, because it relies on translation to and from Arabic, and one that has often led me to elaborate a discourse on translation opposite to the mainstream one, whether in France (or, more generally, in the "global North") or in the Arab world. In order to explain this, I shall have to dwell on my personal trajectory in some detail, and I will do so not out of self-indulgence, but rather as a way of understanding, through a self socio-analysis of sorts, the objective conditions that made this trajectory possible. While doing so, I hope that I will provide the reader with some useful insights on the recent history of the French Orientalist academic field and French-Arab cultural relations as well.

Through the example of the Arabic translations of Pierre Bourdieu, this article analyses the conditions of the introduction and reception of a sociological thought of French origin in the contemporary Arab intellectual field and, more generally, those of the international circulation of ideas in a postcolonial context. The diachronic analysis reveals the interpenetration of logics of import and export, the differences between intellectual and academic national traditions in various Arab countries, as well as the difficult conditions through which modern works of social sciences are published and circulated in the Arab world. Hence, the general economy of these translations is characterized as selective, didactic and militant, while a foreignizing and at times literalist translational norm – notwithstanding the diversity of the translators’ terminological choices, given the absence of a normative framework – dominates their poetics. The author concludes with an analysis of the Arab translator’s habitus, ch...

À travers l’exemple des traductions arabes de Pierre Bourdieu, cet article propose une analyse des conditions de l’introduction et de la réception d’une pensée sociologique de source française dans le champ intellectuel arabe contemporain et, plus généralement, des conditions de la circulation internationale des idées en contexte postcolonial. L’analyse diachronique révèle l’interpénétration des logiques d’importation et d’exportation, les écarts entre les traditions intellectuelles et académiques nationales dans différents pays arabes (Maroc, Liban, Syrie, Egypte), aussi bien que les conditions (matérielles et symboliques) difficiles de l’édition et de la circulation des ouvrages de sciences humaines et sociales dans l’espace arabe. D’où une économie générale de ces traductions caractérisée comme sélective, didactique et militante, et une poétique dominée par une norme traductionnelle dépaysante, voire littéraliste, au-delà de la diversité des choix terminologiques opérés par les traducteurs en l’absence de cadre normatif. L’auteur analyse en conclusion l’habitus du traducteur arabe, caractérisé par une « souffrance de position » spécifique. Une bibliographie des traductions arabes de Pierre Bourdieu est fournie en annexe.

The present bibliography is intended to cover published material dealing with translation in and of the Middle East from a historical and theoretical perspective, with priority given to works dealing with literature, and written in English. As such the titles range from specific case studies of texts and translators, to studies of broader historical and institutional translation movements in the region, to theoretical reflections on the relationship between translation, identity, nation-building and (post)colonial transactions. While Arabic and Turkish are the most heavily represented languages, with their strong histories of state-sponsored translation initiatives, much less work has been done in Persian, Urdu, Hebrew and Kurdish. The topic itself is a relatively new one in relation to the languages, histories and literatures of the Middle East and the titles below – all published within the last twenty years – offer an overview of work done and hopefully point to future research paths.

This article analyzes the translation policies set up in the Arab World since the end of the Second World War, focusing first on the modern Arab discourse on translation, mainly through the example of the 3rd Arab Human Development Report (2003). The Report, based on antiquated and incomplete data, deems the current Arabic translation movement strikingly weak and calls for “an ambitious and integrated Arab strategy” in the field of translation. The article goes on to analyze the programmes carried out by foreign cultural missions active in the region and then examines the indigenous programmes set up by Arab states and institutions. Focusing on the emergence of two discrete moments in local translation policy, the study demonstrates how these indigenous translation programmes were articulated around two complementary logics: a humanistic one, where the aim was to translate into Arabic the ‘masterpieces of world literature and thought’, and a developmentalist one that proposed to make the most rece...

Dans le pantheon de la Renaissance (nahda) arabe, la figure de Ğurgī Zaydān (desormais, plus simplement, Jurji Zaydan) est longtemps restee au second plan. L’histoire litteraire juge avec quelque condescendance ses nombreux romans historiques, et l’histoire intellectuelle n’est guere plus indulgente vis-a-vis du reste de son œuvre. « Jacques Berque, par exemple, n’avait que mepris pour le ‘cosmopolitisme emplume d’arabisme’ » de Jurji Zaydan, rappelle Anne-Laure Dupont (desormais A.-L.D.) dan...

En prelude aux textes des ecrivains de ce dossier, une presentation litteraire, historique et sociale de l’Egypte moderne, de Naguib Mahfouz aux toutes nouvelles generations.

Resume Enfin on est arrives au bar du centre-ville, pleins d’humanite et d’egratignures eparses.

Depuis l'intervention, le 7 janvier 1992, d'une délégation de membres d'al-Azhar (la plus haute autorité sunnite, NDLR) à la Foire internationale du livre du Caire pour faire retirer de la vente plusieurs ouvrages, les polémiques autour de la censure se sont multipliées en Égypte. Cette récurrence du débat n'est pourtant pas liée à une évolution notable de la situation : le durcissement de la confrontation entre le pouvoir et l'opposition islamiste ne s'est pas traduit, pour l'instant, par un...

Je livre ici à l'état d'hypothèses, de réflexions assez générales, ce qui pourrait être le programme d'une recherche qui reste à faire. Mon point de départ est qu'on ne peut comprendre ce qui se passe dans la traduction de l'arabe au français ou du français à l'arabe sans mettre ces deux mouvements en parallèle. Mise en parallèle qui, à ma connaissance, n'a jamais été faite. Il faut donc, avant de s'engager sur ce terrain, tenter de comprendre pourquoi il est en friche. Misère de la traductio...

En guise d'introduction, quelques mots sur les titres : de cette communication, et du colloque dont elle est tiree. Quand, il y a quelques semaines, ma collegue Amal Farid m'a demande le titre de mon intervention pour l'inserer dans le programme du colloque, je lui ai indique : « L'edition d'ouvrages traduits du francais en Egypte : un point de vue exterieur ». Puis, tandis que je preparais mon texte, il m'est apparu que mon point de vue, plutot qu'exterieur (en tant qu'emanant d'un etranger)...

En observant la scene litteraire egyptienne dans les annees quatre-vingt-dix, on est frappe par des evolutions apparemment contradictoires : la recrudescence notable des affaires de censure, qui tend a developper chez les ecrivains une mentalite d’assieges, contraste avec l’impression que l’on a, a lire leur production, d’une liberte plus grande qu’elle ne l’a jamais ete dans le siecle qui vient de s’achever. Cet ecart entre l’etat reel de la liberte d’expression – dans l’ecrit a visee litter...

L’etude comparee des flux de traduction du francais vers l’arabe et, a l’inverse, de l’arabe vers le francais, offre une illustration assez exemplaire de l’echange culturel inegal entre une langue centrale ou dominante (le francais) et une langue peripherique ou dominee (l’arabe). Il peut sembler paradoxal de classer l’arabe dans les langues peripheriques. Langue maternelle de plus de 200 millions de personnes et seconde langue d’au moins 100 autres millions (ce qui la classe au 5e ou au 6e r.

Tradução de: Paulo Daniel Farah.A social linguistic and geopolitical study of the Arabic language from its formation to the present day passing through arab renaissance (nahdah), the arabism, the arabization, the linguistic homogenization/standardization, the translation fluxes and the cultural interchange.

Perhaps the only consensus Egyptian poets and critics can reach today--given the different orientations and generations present--is the description of the poetic field in terms of a crisis. The article does not attempt to analyze the dimensions of such a crisis; rather it attempts to map the varied trends in poetic activity in contemporary Egypt. Inasmuch as the struggle in this arena revolves around what deserves to be called poetry most studies, if not all, whether written by poets or critics tend to concentrate on a specific poetic current, dismissing the rest. This article approaches various poetic currents from the perspective of literary sociology, thus it follows in its categorizations the most widely recognized criterion, namely that of form. It sets out to delineate the reasons behind the ongoing popularity of traditional metrical (`amudi) poetry, then moves on to draw the outlines of the critically dominant trends in free verse and finally the efforts of the generations of the 1970s and after to go beyond them. A short history of dialectical (`amiyya) poetry is also traced as a parallel, often neglected, to that of poetry in the literary idiom (fusha). ********** En 1953, la Revue du Caire publiait un numero special intitule "Cinquante ans de litterature egyptienne," introduit par un article d'Ahmed Amin (1878-1954), grande figure intellectuelle de l'entre-deux-guerres, ou il dressait un bilan de l'evolution de la production nationale dans les divers genres litteraires. A. Amin ecrivait: Quant a la poesie, disons qu'elle a suivi les traces de la poesie ancienne dans sa metrique et ses rimes et tres souvent dans ses sujets: cette poesie s'arrete a Chawki et Hafez. Aujourd'hui, une certaine perplexite regne: la poesie des anciens n'est plus au gout du peuple, et aucune renovation ne vient s'y substituer. [...] En Egypte et dans le monde arabe se developpe un mouvement parmi la jeunesse pour former une poesie nouvelle traitant de sujets nouveaux [...] ou nous avons ete devances par les Europeens. On se debarrasse aussi de la rime et de la metrique traditionnelle des anciens. Mais on observe que les gens cultives des nations arabes ont accueilli ce genre de vers avec une sorte d'indifference, parce que leur oreille musicale ne s'y est pas encore accoutumee. Ils ont senti que ce genre de poesie ne jaillissait pas de son propre milieu et ne s'harmonisait pas avec leur propre gout; la question reste confuse et on ne sait trop comment elle evoluera. Mais la prose est solide et stable parce qu'elle a su s'adapter a la situation presente [...]. C'est pourquoi nous avions raison de dire que la prose arabe est tres proche de la prose occidentale dans ses differents genres. Elle ne s'immobilise pas, mais se conforme a l'evolution des sciences et des cultures et aura, a ce qu'il semble, un avenir brillant. (1) Ce texte quasi cinquantenaire resume a merveille les situations respectives de la poesie et de la prose de fiction arabes. Empruntee a l'etranger, la fiction romanesque n'a pas connu de mise en cause radicale de ses canons esthetiques, mais plutot une serie d'amenagements visant a l'acclimater a la culture d'emprunt, qui ont permis son "enracinement" (ta'sil); a l'inverse, la tradition poetique arabe, minee par les assauts des avant-gardes successives tout au long du siecle, ne leur a pas moins oppose une considerable force d'inertie, de sorte qu'aujourd'hui le champ poetique apparait, selon la metaphore du poete libanais `Abduh Wazin, comme une "terre devastee"--amusant detournement du Waste Land de T. S. Eliot, que la mouvance de la revue Shi`r erigea en parangon de la modernite poetique avant de s'eriger elle-meme en "pionniere" de la modernite poetique arabe. (2) Deux grandes manifestations organisees recemment au Caire par le Conseil superieur de la Culture ont donne la mesure de ce contraste entre champ romanesque et champ poetique arabes: le Festival de la creation poetique (23-27 novembre 1996), bruissant de polemiques et d'excommunications reciproques, avec ses soirees poetiques ou de nombreux poetes invites preferaient ne pas se montrer plutot que de lire leurs textes avant ou apres tel ou tel de leurs collegues, etc. …

International audience; Literary studies only escaped from the nationalistic paradigm about twenty years ago. This nationalist paradigm dominated literature after the Enlightenment replaced a universal literary culture with a national one. For a long time, only comparative literature tried to find links between national literary traditions, not always very successfully. In the last two decades, the dominance of this nationalist paradigm became challenged by translation studies and postcolonial studies. While the first has stressed exchanges between literary traditions, the second has followed the emergence of a new literary space on a world scale, including not only the old colonial centers, but also the numerous peripheries. By substituting the concept of "Arabic literary space" for the notion of "Arabic literature", and thus including in it translations, one can reconfigure literary studies and tackle them more systematically. The concept covers not only translations from and to Arabic, but also works written by Arabs in other languages such as English or French, as well as the writings that introduce into Arabic literature themes and elements derived from other languages, whether colonial languages like English or French, or minority languages in the Arab world (Berber, Tuareg, Nubian, Kurdish, etc.). A final category could be the translation into Arabic ("bringing home") of works written in other languages by Arab authors. The article deals with Egypt, but its approach could be extended to the entire Arab world.