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Les piles à combustible, dont le principe de fonctionnement est connu depuis le milieu du XIXème siècle, permettent de produire simultanément de l’électricité, de l’eau et de la chaleur à partir de combustibles et comburants tels que l’hydrogène et l’oxygène. À la fin des années cinquante, ces générateurs électrochimiques connaissent des perfectionnements majeurs, notamment grâce aux travaux de l’Anglais Francis T. Bacon, et sont utilisés aux États-Unis par la NASA (Aeronautics and Space Administration) au sein de ses programmes spatiaux. En France, des études sont mises en place au même moment dans des laboratoires publics et privés, tels que ceux d’Alsthom, de l’Institut français du pétrole et du CNRS (Centre national de la recherche scientifique), sous l’égide des Armées et de la DGRST (Délégation générale à la recherche scientifique et technique), organisme d’État chargé de la politique de la recherche. Jusqu’au début des années quatre-vingt, des millions de francs sont ainsi investis et des centaines de chercheurs, ingénieurs et techniciens sont mobilisés pour améliorer la technique, travailler à son adaptation aux automobiles électriques, aux trains, aux sous-marins, à la construction de centrales de production industrielle d’électricité ou encore à la fourniture de solutions militaires. Alors que de nos jours les piles à combustible apparaissent en France comme des options majeures pour la transition énergétique, c’est tout l’objet de cette thèse que de retracer, restituer et analyser cette partie de leur histoire grâce à une enquête de terrain fondée sur la récolte d’archives et la réalisation d’entretiens avec des acteurs ayant participé aux recherches. Nous mettrons tout d’abord au jour les conditions socio-historiques et les dynamiques structurelles qui font que les piles à combustible deviennent un thème d’intérêt en France à la fin des années cinquante. Nous montrerons ensuite comment les études sont organisées puis réorientées dans les années soixante et soixante-dix en fonction de l’évolution du collectif de pensée et du réseau social créés autour de la technique. Enfin, nous examinerons l’ensemble des raisons politiques, économiques, scientifiques et sociales pour lesquelles ces travaux sont presque tous abandonnés au début des années quatre-vingt. / Fuel cells, which operation principle is known since the middle of the 19th century, allow to produce electricy, water and heat simultaneously from fuels and combustives like hydrogen and oxygen. At the end of the 50s, these electrochemical generators are perfected, particularly thanks to the work of Francis T. Bacon in England, and are used in the USA by NASA (Aeronautics and Space Administration) for space programs. In France at the same period, private and public laboratories as Alsthom, the IFP (French Petroleum Institute) and the CNRS (French National Center for Scientific Research) start their own studies under the supervision of the Ministry of Defense and the DGRST (General Commission for for Scientific and Technical Research), a national institution in charge of scientific research policy. Until the beginning of the 80s, millions are thus invested and hundreds of researchers, engineers and technicians are mobilized to improve fuel cells, work on their adaptation to electrical cars, trains, submarines, on the construction of fuel cell power plants or specific military equipments. Now that in France fuel cells are considered as major options for energy transition, the objective of this dissertation paper is to analyze this period of their history thanks to a field investigation based on numerous archives and interviews with stakeholders who contributed to researches. We will first expose socio-historical conditions and structural dynamics which make fuel cells become a theme of national interest at the end of the 50s. We will then show how studies are organized and reoriented in the 60s and 70s according to the evolution of the thought collective and the social network created around fuel cells. Finally we will examine all political, economic, scientific and social reasons which led to drop almost all fuel cell researches in the country at the beginning of the 80s.

From 1960-4 the British government embarked on two large-scale space research programmes to develop satellite launchers. After first being cancelled as a military project in 1960, the Blue Streak missile was converted into the first stage of a British-led European collaborative project to build a three stage satellite launcher (through the European Launcher Development Organisation - ELDO). Born out of the Black Knight warhead re-entry testing vehicle, the independent Black Arrow project aimed to launch small satellites for scientific experimentation. With European collaborations, American scientific knowledge, and an Australian testing site, decisions affecting British space research had wide reaching diplomatic as well as domestic consequences. However, by 1973, both of these programmes had been cancelled. By examining the complex formation of British policy on these two space research projects, I will identify the alliances of actors involved focusing on understanding the role of civil servants, and the domestic, economic, and foreign policy priorities which directed their policy-making. This thesis seeks to address two contradictions raised by British policy on space research, and historical analysis of this period. Firstly, if we accept that Britain was not in decline in this period, the how can the history of two projects which is dominated by their cancellation be explained? Secondly, how British governments could reconcile their policy towards ELDO (threatening to withdraw almost yearly from 1966-73) with their stated aim to accede to the European Communities and their repeated rhetoric that the increased potential for scientific and technological collaboration was a key benefit of British accession? In order to address these contradictions I focus on decisions and decision-makers within government. By tracking policy arguments and options to their very beginnings I show throughout this thesis the way in which individuals frame, shape and direct policy. This thesis provides new insights into the foreign and domestic policy priorities of the four governments in this period by tracking the balance of priorities in policy making in two major space research projects. Close examination of ELDO and Black Arrow highlights that their cancellation is not a symbol of British decline, but instead represent active choices by decision-makers to engage in new areas of research. This supports the work of historians challenging the idea that Britain was in decline in this period, and suggests that cancelled projects should be re-examined.

Produits industriellement dès 1910, les duralumins (alliages Al-Cu-Mg) sont les premiers alliages d'aluminium à durcissement structural ayant permis le développement de l'aéronautique. Bien que les alliages Al-Zn-Cu de la famille 7xxx et les matériaux composites soient aujourd'hui majoritaires dans la construction des avions, ces alliages Al-Cu-Mg de la famille 2xxx restent un matériau de référence pour les structures aéronautiques. Cependant, même s'il est un produit industriel récent et largement utilisé, avec une grande production de documents écrits, il existe une perte d'informations liée à la politique d'archives appliquée par les industriels. Cette perte d'information touche particulièrement les données physico-chimiques des matériaux utilisés pour la construction des avions mais aussi l'explication des choix techniques des avionneurs. La rénovation du Breguet 765 Sahara n°504 64-PH aux Ailes Anciennes Toulouse est une opportunité d'étudier les duralumins aéronautiques de la fin des années 1950. Il est possible de récupérer les pièces déposées et remplacées avant qu'elles ne soient jetées et définitivement perdues avec les informations qu'elles contiennent. En comparant l'analyse en laboratoire de ces matériaux arrivés jusqu'à nous avec les documents d'archives et la documentation actuelle, il est possible d'entreprendre un retour sur expérience. Nous pouvons envisager de comparer ce qui a été réalisé avec ce qui a été initialement prévu lors de la conception de l'avion et de compléter les données connues de ces matériaux avec les techniques d'analyses métallurgiques actuelles. Ces alliages peuvent également constituer une première référence des duralumins aéronautiques des années 1950 et contribuer à l'étude de l'évolution sur de grandes échelles de temps des propriétés mécaniques par rapport aux valeurs minimum exigées du constructeur. / Industrially produced since 1910 and used for the construction of Breguet XIV in 1916, the duralumins (Al-Cu-Mg alloys) are the first age-hardening aluminum alloys that were at the origin of the aeronautics development. Although Al-Zn-Cu alloys of the 7xxx family and composite materials are more widely used today, these Al-Cu-Mg alloys of the 2xxx family remain a reference material for aircraft structures. However, although it is an industrial material, with a large production of written documents, the archiving policy applied by manufacturers causes a loss of information. There is thus a difficulty to retrieve pertinent chemical and physical data of material used in aircraft construction, but also to understand the choices made about the material and process used by the manufacturers. The renovation of the Breguet 765 Sahara n°504 64-PH by the association Ailes Anciennes Toulouse is an opportunity to study aeronautical duralumins of the late 1950s. It is possible to recover elements need to be replaced before they are permanently lost, with the information contained therein. By comparing laboratory analysis with archival and current literature, it is possible to give a feedback on these ancient materials. We can compare what was done with what was originally planned in the design of the aircraft and complete the known data of these materials with current metallurgical technical analysis. These alloys can also be a first reference for aeronautical duralumins of the 1950s and contribute to the study of the long-term evolution of mechanical properties compared to minimum values ??required by the manufacturer.

This study analyses the history of a large hydroelectric scheme – the Great Ruaha power project in Tanzania. The objective is to establish why and how this specific scheme came about, and as part of this to identify the key actors involved in the decision-making process, including the ideological contexts within which they acted. Although the Tanzanian actors and the World Bank (IBRD) are discussed, main focus is on the Swedish actors on project level.Kidatu, the first phase of the Great Ruaha power project (constructed between1970-1975), became the first large-scale hydropower station in Tanzania. As such, it paved the way for Tanzanian entrance into the Big Dam Era and significant changes within the Tanzanian landscape. As well as the dry river bed at Kidatu, and the small reservoir that precedes it, the Great Ruaha power project also involved the creation of a huge artificial lake, the Mtera reservoir. The Kidatu hydropower station was the first large undertaking within Swedish bilateral aid, and implied the takeover of control of hydropower construction in Tanzania by Swedish enterprises, replacing the enterprises of the former colonial power. A hydropower plant is a complex technoscientific artefact. The construction of a hydropower plant is preceded by a large number of technological choices, scientific prestudies and estimations of costs and revenues. A hydropower plant is also a complex social creation, and is as such filled with social actors engaged in conflicts, compromises and power structures. The decision to construct Kidatu hydropower station was a result of negotiations and activities within what is called “development assistance”. This brings in yet another dimension, the political one, involving export and import of technology, foreign capital, and foreign influence in decision-making processes, as well as ideas about how to bring development and progress to a people supposed to be living in “poverty and misery”. The study is divided into three main parts. The first part analyses the context of Swedish development assistance in the support to the construction of hydropower plants. This part discusses Swedish state-supported hydropower exploitation of indigenous people’s territory within Sweden’s borders in the 20th century and the background of Swedish development assistance, from the 1950s to the early 1960s. The second part analyses the event of Swedish development assistance entering Tanzania and the Great Ruaha power project, with the main focus being on the period 1965 – 1970. The third part is an analysis of the technoscientific basis for the decisions taken to implement the Great Ruaha hydropower scheme. Main focus is on the period 1969-1974, discussed against the backdrop of precolonial and colonial studies. While focus is on the 1960s and 1970s, in both part two and three events in the 1980s and 1990s are discussed. The study shows that although Sweden was not a colonial power in Tanzania, colonial imagery, and relations to the colonial era, as well as Sweden’s background of internal colonialisation, exerted an influence on the decision-making process and the actors involved in the Great Ruaha power project.The study is mainly based on archival sources, complemented with oral sources from Tanzania and Sweden. Recognizing the complexity of large-scale hydropower and the attempts to control watercourses that large scale hydropower necessitates, in the specific context of decolonisation and development assistance that the decision-making process behind the Great Ruaha hydropower scheme reveals, the analysis of the actors involved is based on feminist and postcolonial perspectives. / QC 20100825

Made available in DSpace on 2016-04-28T14:16:37Z (GMT). No. of bitstreams: 1 Edaival Mulatti.pdf: 1316493 bytes, checksum: 2ddebbfbb24364b182ea454f86c50397 (MD5) Previous issue date: 2008-10-23 / The Royal Institution, English organization founded at the end of the eighteenth century in London and existing in this day and age as an institution dedicated to research in the theory and dissemination of science, was born with the purposes of an institution of public character, depending on financial contributions. Within a conception of science, categorized by its founders as "useful science," the Royal Institution had as main goals, the diffusion of knowledge and application of science in the life of the population. For the present work, we studied up some of the social and political circumstances present in England at the end of the eighteenth century, and provided evidence to the understanding of the reasons that enabled the creation of that institution. Also, we tried to identify in the creation and consolidation of that institution, the role played by personalities of the time, as Joseph Banks, Benjamin Thompson, Thomas Young, Thomas Garnett and Humphry Davy. This work was based on the study of the following documents: "Proposals for forming by subscription, in the Metropolis of the British Empire, the Public Institution for diffusing the knowledge and facilitating the general introduction of useful mechanical inventions and improvements, and for teaching, by Philosophical Lectures and courses of Experiments, the application of science to the common purposes of life.", document-creation of the Royal Institution, authored by Benjamin Thompson and dated March 1799,"The discourse introductory to the Course of Lectures on Chemistry , Delivered in the Theatre of the Royal Institution, on the 21st of January, 1802," inaugural lecture of the Royal Institution Humphry Davy, and "The Bakerian Lecture, on some chemical Agencies of Electricity," lecture in which Davy presented the results of their research on electrolysis, made the Royal Institution and presented at the Royal Society on November 20 de1806. The focus of this work was in the study of the model for dissemination of knowledge established on the origins of the Royal Institution, as well as some of the changes that have made this model a strong point of support for the Royal Institution to be seen, at the beginning of the nineteenth century, as a major scientific institutions of England / The Royal Institution, organização inglesa fundada no final do século XVIII em Londres e existente nos dias de hoje como uma instituição voltada a pesquisas no campo teórico e divulgação da ciência, nasceu com os propósitos de uma instituição de caráter público, dependendo financeiramente de contribuições. Dentro de uma concepção de ciência, categorizada por seus fundadores como ciência útil , a Royal Institution tinha como principais objetivos, a difusão do conhecimento e aplicação da ciência na vida da população. Para o presente trabalho, estudou-se algumas das circunstâncias sociais e políticas presentes na Inglaterra no final do século dezoito, e que forneceram elementos para o entendimento dos motivos que propiciaram a criação de tal instituição. Procurou-se também identificar, na criação e consolidação dessa Instituição, o papel desempenhado por personalidades da época, como Joseph Banks, Benjamin Thompson, Thomas Young, Thomas Garnett e Humphry Davy. Esta dissertação baseou-se no estudo dos seguintes originais: Proposals for forming by subscription, in the Metropolis of the British Empire, a Public Institution for diffusing the knowledge and facilitating the general introduction of useful mechanical inventions and improvements, and for teaching, by courses of Philosophical Lectures and Experiments, the application of science to the common purposes of life , documento de criação da Royal Institution, de autoria de Benjamin Thompson e datado de março de 1799, A discourse introductory to a Course of Lectures on Chemistry, Delivered in the Theatre of the Royal Institution, on the 21st of January, 1802 , palestra inaugural de Humphry Davy na Royal Institution, e The Bakerian Lecture, on some chemical Agencies of Electricity , palestra na qual Davy apresentou os resultados de suas pesquisas sobre eletrólise, efetuadas na Royal Institution e apresentadas perante a Royal Society em 20 de novembro de1806. O ponto central desse trabalho situou-se no estudo do modelo de difusão do conhecimento formulado nas origens da Royal Institution, bem como em algumas de suas modificações que fizeram desse modelo um forte ponto de apoio para que a Royal Institution se projetasse, no início do século dezenove, como uma das principais instituições científicas da Inglaterra