[ES] El etileno representa uno de los pilares de la industria química actual como parte de los denominados "productos químicos básicos". Los procesos de recuperación y valorización de etileno actuales están basados en fuentes de carbono de origen fósil y son operados a gran escala, por lo que tienen asociado un elevado coste energético y contribuyen significativamente a la emisión de gases de efecto invernadero. La preocupación actual por avanzar hacia la descarbonización de la industria química ha impulsado el diseño de procesos químicos más sostenibles. En este contexto, el diseño de nuevos procesos catalíticos (tándem), con alta economía atómica y operando a condiciones de operación más suaves, supone una alternativa de gran interés. La presente tesis doctoral se centra en el desarrollo de procesos catalíticos alternativos para la conversión de (bio-)etileno en productos de alto valor añadido, como el propileno o los compuestos oxigenados C3. En primer lugar, se ha estudiado el efecto de emplear diferentes soportes basados en óxidos metálicos en catalizadores de Rh de dispersión atómica para la hidroformilación de etileno en fase gas para producir propanal. Entre los materiales estudiados con diferente grado de reducibilidad superficial, el catalizador Rh1/SnO2 mostró el mejor rendimiento, con altos valores de actividad y con una selectividad a hidroformilación prácticamente total, a unas condiciones de operación muy suaves (P=20 bar, T=383 K). El comportamiento extraordinario de este material se ha atribuido a la capacidad de formar vacantes de oxígeno superficiales, lo que facilita la formación de especies de Rh de alta flexibilidad de coordinación y con propiedades electrónicas que se asemejan a de los catalizadores moleculares en disolución empleados industrialmente. A continuación, se estudió el uso de catalizadores bimetálicos Ag-Pt para la hidrogenación selectiva de aldehídos en presencia de olefinas. Para la composición óptima del catalizador (<4 at% Pt), se descubrió que las especies de Pt estaban altamente dispersas sobre la matriz de Ag, posiblemente en forma de las denominadas "aleaciones de átomos aislados". Dicho catalizador se combinó junto al catalizador de hidroformilación altamente selectivo Rh1/SnO2 en un proceso de hidroformilación reductiva, que permitió la conversión directa de etileno a 1-propanol con selectividad prácticamente total (98%) a conversiones de etileno >50%. Por último, se estudió la conversión de etileno a propileno mediante procesos tándem de dimerización-metátesis. Para ello, se estudiaron métodos de calentamiento específico y termometría selectiva combinando técnicas de calentamiento por inducción y termometría por luminiscencia. Dichos métodos resultaron adecuados para solventar las incompatibilidades de temperatura inherentes a los procesos de catálisis tándem del estado del arte y desbloquear, de esta manera, rendimientos inaccesibles para procesos operados mediante calentamiento convencional. / [CA] L'etilè representa un dels pilars de la indústria química actual com a part dels denominats "productes químics bàsics". Els processos de recuperació i valorització d'etilé actuals estan basats en fonts de carboni d'origen fòssil i són operats a gran escala, per la qual cosa tenen associat un elevat cost energètic i contribueixen significativament a l'emissió de gasos d'efecte d'hivernacle. La preocupació actual per avançar cap a la descarbonització de la indústria química requereix el disseny de processos químics més sostenibles. En este context, el disseny de nous processos catalítics (tàndem), amb alta economia atòmica i operant a condicions d'operació més suaus, suposa una alternativa de gran interés. La present tesi doctoral se centra en el desenvolupament de processos catalítics alternatius per a la conversió de (bio-)etilè en productes d'alt valor afegit, com el propilé o els compostos oxigenats C3. En primer lloc, s'ha estudiat l'efecte d'utilitzar diferents suports basats en òxids metàllics en catalitzadors de Rh de dispersió atòmica per a la *hidroformilación d'etilè en fase gas per a produir probresca. Entre els materials estudiats amb diferent grau de reducibilidad superficial, el catalitzador Rh1/SnO2 va mostrar el millor rendiment, amb alts valors d'activitat i amb una selectivitat a hidroformilació pràcticament total, a unes condicions d'operació molt suaus (P=20 bar, T=383 K). El comportament extraordinari d'este material s'ha atribuït a la capacitat de formar vacants d'oxigen superficials, la qual cosa facilita la formació d'espècies de Rh d'alta flexibilitat de coordinació i amb propietats electròniques que s'assemblen a dels catalitzadors moleculars en dissolució utilitzats industrialment. A continuació, es va a estudiar l'ús de catalitzadors bimetàl·lics Ag-Pt per a la hidrogenació selectiva d'aldehids en presència d'olefines. Per a la composició òptima del catalitzador (<4 at% Pt), es va descobrir que les espècies de Pt estaven altament disperses sobre la matriu de Ag, possiblement en forma dels denominats "aliatges d'àtoms aïllats". Aquest catalitzador es va a combinar al costat del catalitzador de hidroformilació altament selectiu Rh1/SnO2 en un procés de hidroformilació reductiva, que va permetre la conversió directa d'etilè a 1-propanol amb selectivitat pràcticament total (98%) a conversions d'etilé >50%. Finalment, es va a estudiar la conversió d'etilè a propilè mitjançant processos tàndem de dimerització-metàtesi. Per a això, es van a estudiar mètodes de calfament específic i termometria selectiva combinant tècniques de calfament per inducció i termometria per luminescència. Aquests mètodes van a resultar adequats per a solucionar les incompatibilitats de temperatura inherents als processos de catàlisis tàndem de l'estat de l'art i desbloquejar, d'esta manera, rendiments inaccessibles per a processos operats mitjançant calfament convencional. / [EN] Ethylene constitutes one of the pillars of the current chemical industry as part of the so-called "commodity chemicals". Current ethylene recovery and valorization technologies are based on fossil-based carbon feedstocks operated at the large scale, which are very energy-intense and contribute to important greenhouse gas emissions. The current concern on progressing towards a defossilized chemical industry calls for the design of more sustainable chemical processes. In this regard, the design of novel (tandem-) catalytic processes, with high atom economy at milder operation conditions, is desired. In this thesis, the conversion of (bio-)ethylene into high-added value chemicals such as propylene and C3 oxygenates via alternative catalytic processes is addressed. Firstly, metal oxide support effects have been explored in Rh single-atom catalysts for gas-phase ethylene hydroformylation to propanal. By exploring a series of materials with different surface reducibility, a Rh1/SnO2 catalyst showed to deliver the best performance, with high Rh-specific activity and essentially full selectivity to hydroformylation under very mild operation conditions (P=20 bar, T=383 K). The unconventional performance of this material has been ascribed to the capacity of forming surface oxygen vacancies on the SnO2 support, which triggers the formation of Rh species that resemble the electronic and coordination flexibility properties of Rh centers in benchmark molecular complexes operating in solution. Next, bimetallic Ag-Pt catalysts were explored, computationally and experimentally, for the selective hydrogenation of aldehydes in the presence of olefins under the same set of mild operation conditions. For the optimal catalyst formulation (<4 at% Pt), Pt species were highly dispersed within the Ag matrix, possibly forming a so-called "single-atom alloy". This catalyst was integrated with the fully selective hydroformylation Rh1/SnO2 catalyst in a reductive hydroformylation process, which unlocked the direct conversion of ethylene to 1-propanol with almost full selectivity (98%) at ethylene conversion >50%. Finally, the direct conversion of ethylene into propylene via tandem dimerization-metathesis has been explored. Catalyst-specific heating and thermometry methods, combining induction heating and remote luminescence thermometry, proved suitable to alleviate temperature incompatibilities inherent to state-of-the-art tandem catalytic processes and unlock catalytic performances inaccessible to conventionally heated conversion processes. / I would like to thank the Spanish Ministry of Science, Innovation and Universities (MCIU) for my FPU grant (FPU17/04701) and the European Research Council (ERC) under the Horizon 2020 research and innovation program (ERC-CoG-TANDEng; grant agreement 864195), which have made possible the realization of this thesis. I would like to thank the Institute of Chemical Technology (ITQ) and the Spanish Research Council (CSIC) for giving me access to the infrastructure I have used for my PhD work. I would like also to thank the Institute of Materials Science of Madrid (ICMM) and the Massachusetts Institute of Technology (MIT) for giving me access to their facilities during my short stays. Thanks also to the ALBA synchrotron and, particularly, to the CLÆSS beamline for making possible the access to synchrotron experiments granting us with several beamtimes. Finally I would like to thank the Chemical and Nuclear Engineering department (DIQN) of the Polytechnic University of Valencia (UPV), for hosting me as a teaching assistant during these years / García Farpón, M. (2024). Tandem Catalytic Processes for Selective Ethylene Valorization into C3 Chemicals [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/203261

Food waste in agricultural production is a key topic in sustainability studies. The goal of this study was to look at the structural elements that contribute to food waste of fruits and vegetables and provide solutions to solve the multifaceted problem based on what the role of distributors is in that matter. The study was founded on the philosophy of sustainability and justice, and it used a qualitative technique that included interviews with farmers and stakeholders from France. The findings indicate that economic profitability, environmental effect, social fairness, and policy governance are all interrelated causes of food waste in agricultural supply chains. Organizations may utilize these insights to create strategies for minimizing food waste, encouraging responsible consumption, production, and valorization, and creating more fair and sustainable agricultural systems.

La cellulose, bio-polymère composé d’unités glucose, est un composé largement disponible au sein de la biomasse lignocellulosique. Sa dépolymérisation sélective en synthons se heurte cependant à sa forte résistance aux transformations chimiques du fait de sa structure semi-cristalline. L’objectif de la thèse est d’étudier la transformation de la cellulose par catalyse hétérogène. Il a été montré qu’une dépolymérisation partielle de la cellulose en milieu aqueux était promue par les protons issus de l’autoprotolyse de l’eau à 190°C. L’ajout d’un catalyseur solide ayant une acidité de BrØnsted forte dans le milieu réactionnel s’est révélé peu influent sur la conversion de la cellulose. En revanche, la présence de catalyseurs solides possédant une acidité de Lewis forte augmente significativement la conversion de la cellulose en formant sélectivement de l’acide lactique. Cette orientation sélective de la réaction est attribuée à l’aptitude des sites acides de Lewis à coordiner les oligosaccharides solubilisés. L’ajout d’une fonction métallique (Pt) sur un acide de Lewis solide augmente aussi significativement la conversion de la cellulose, en produisant sélectivement de l’acétol et du propylène glycol. La fonction métallique, sous atmosphère d’hydrogène, ne se limite pas à l’hydrogénation des produits finaux mais pourrait aussi intervenir dans des étapes de transfert d’hydrures et de génération de protons. Une conversion efficace de la cellulose résulte ainsi d’une action combinée des protons issus du milieu aqueux générant des oligosaccharides et des sites actifs des catalyseurs hétérogènes bifonctionnels métal-acide. / Cellulose, a biopolymer composed of glucose units, is an abundant and renewable resource. Its selective depolymerisation into building blocks is difficult due to its strong resistance to chemical reactions ascribed to its semi-crystalline structure. The aim of the thesis is to study the transformation of cellulose by heterogeneous catalysis. It has been shown that a partial cellulose depolymerisation in aqueous media was promoted by the hydroxonium ions generated in situ by water autoprotolysis at 190°C. The presence of a solid BrØnsted acid in the reaction media neither improved the cellulose conversion nor led to a particular selectivity into a valuable product. By contrast, solid Lewis acids were capable of significantly improving the cellulose conversion but also of favoring the formation of lactic acid in high yield. It is proposed that the solid Lewis sites intervene via coordination of oligosaccharides, issued from cellulose depolymerisation initiated by hydroxonium ions from water. The addition of a metallic phase such as Pt° on a solid Lewis acid support has also led to remarkable performances in term of extent of cellulose conversion and selectivity towards acetol and propylene glycol. The metallic bi-functionnal catalyst, under hydrogen atmosphere, not only leads to hydrogenated products but could also intervene into hydrides transfer elementary steps. An efficient cellulose conversion is the result of a combined action of hydroxonium ions provided by the hot water media with active sites of the bifunctionnal heterogeneous catalysts.

Made available in DSpace on 2016-08-10T10:50:45Z (GMT). No. of bitstreams: 1 Claudia Gomide Guimaraes.pdf: 20307041 bytes, checksum: 57713fb6685c1bedb76814b9c6e368b8 (MD5) Previous issue date: 2010-01-14 / In the last decades, the discussion of the environmental problems became a thematic one obligatory in the daily city dweller. The green areas became the principal icons of defense of the environment due to your degradation and for the small space that is destined them in the urban centers. The evolution of the urban park on these last two centuries accompanied the changes urbanísticas of the cities, they are like this, an important testimony of the values social, economical and cultural of the urban space. In the several speeches on the city, specifically on the urban parks, in your great majority, a consent was built expresses for the attributed positive values the those public spaces. Though, sees more closely, that consent doesn't seem to match with the multiple realities that involve the parks. The population can show in a different way in relation to the presence of the parks in your neighborhood. Besides, it is possible that they can act in the valorization or depreciating of your entornos. It is observed that there are ambivalences in relation to the urban parks and that those link directly with the place where you/they are proposed. To show those dualities and those paradoxes between central areas and outlying areas with relationship to the presence of parks was the challenges of this research wor. / Nas últimas décadas, a discussão dos problemas ambientais tornou-se uma temática obrigatória no cotidiano citadino. As áreas verdes tornaram-se os principais ícones de defesa do meio ambiente em decorrência de sua degradação e pelo exíguo espaço que lhes é destinado nos centros urbanos. A evolução do parque urbano nestes dois últimos séculos acompanhou as mudanças urbanísticas das cidades, são assim, um testemunho importante dos valores sociais, econômicos e culturais do espaço urbano. Nos vários discursos sobre a cidade, especificamente sobre os parques urbanos, em sua grande maioria, construiu-se um consenso expresso pelos valores positivos atribuídos a esses espaços públicos. Todavia, visto mais de perto, esse consenso não parece condizer com as múltiplas realidades que envolvem os parques. A população pode manifestar-se de forma distinta em relação à presença dos parques em sua vizinhança. Além disso, é possível que eles possam atuar na valorização ou desvalorizando de seus entornos. Observa-se que há ambivalências em relação aos parques urbanos e que essas relacionam-se diretamente com a localidade onde são propostos. Mostrar essas dualidades e esses paradoxos entre áreas centrais e áreas periféricas com relação à presença de parques foi os desafios deste trabalho de pesquisa.

La valorisation de chaleur fatale industrielle en flux gazeux à haute température peut bénéficier de technologies de stockage thermique thermocline, fonctionnant sur la base d’un matériau de stockage céramique et d’un caloporteur gazeux (air). La diversité des gisements de chaleur fatale et des débouchés potentiels met en évidence la nécessité d’un procédé de stockage versatile et robuste. Ce travail de thèse consiste à accompagner le développement de l’entreprise Eco-Tech Ceram, dont les deux activités sont le développement d’une unité de stockage thermique, et le développement de matériaux céramiques issus de sous-produits industriels destinés à une utilisation dans de telles unités. Concernant l’axe stockage, il s’agit de réaliser une validation expérimentale du concept EcoStock via des essais sur des pilotes représentatifs, notamment concernant la sensibilité des performances au débit de décharge, et à la nature de la ressource thermique disponible en charge (débits et températures d’entrées variables).Concernant l’axe matériau, il s’agit de développer une céramique frittée issue de mâchefer d’incinérateur, et destinée à une utilisation en tant que matériau de garnissage dans un système thermocline à lit en vrac, via une approche expérimentale, dans une démarche d’écologie industrielle et avec l’objectif de diminuer autant que possible les coûts de production et les impacts environnementaux, en calquant les méthodes d’élaboration sur celles des céramiques de batiment (briques et tuiles) dont les capacités industrielles sont pré-existantes. r. / The recovery and valorization of high-temperature gaseous waste heat streams can benefit from the development of thermocline thermal energy storage, based on the use of a ceramic material as a solid filler and gases (including air) as heat transfer fluid. The wide diversity of waste heat streams implies developping a versatile and robust system, able to operate in such various conditions.This thesis aims at supporting the development of the company Eco-Tech Ceram, which focuses on developing a compact thermocline air/ceramic thermal storage unit (named EcoStock), and developing ceramics produced from industrial inorganic byproducts, designed to be used as thermal energy storage material. Regarding the « thermal storage » topic, this thesis is focused on the experimental validation of the EcoStock concept, through experimental campaigns on a representative pilot-scale system, especially regarding the influence of operating conditions over performances, and the sensitiviy of the system’s efficiency when discharged at different power level, or charged with low-quality heat streams (varying mass flow rate and inlet temperature during charging phase). Regarding the « ceramic » topic, this thesis is focused on developing a sintered ceramic based on municipal waste incinerator bottom ashes compatible with high temperature thermocline system, with an experimental approach, taking in consideration industrial potential of such ceramics by making industrial mass production of such material realistic, using already widely available industrial processes from the bricks and tiles industries.Keywords: thermal storage, thermocline, experimental validation, waste heat, high temperature, sintered ceramics, incinerator bottom ash valorization.

Pendant plusieurs siècles, le Yémen n’a pas porté d’intérêt institutionnel à ses archives, étant isolé du monde extérieur à cause de l’occupation ottomane au nord du pays et de l’occupation britannique au sud. Depuis la révolution de 1962, le besoin de disposer d’archives bien organisées et accessibles est apparu et la création du Centre National des Archives en 1991 a permis d’améliorer considérablement la situation. L’objectif de cette thèse est d’étudier l’intérêt que l’État yéménite a porté au patrimoine archivistique. Elle rappelle l’histoire et le développement de l’archivage dans les ministères et les institutions gouvernementales yéménites depuis la révolution de 1962 jusqu’à aujourd’hui. Elle présente la création des Archives nationales, avec l’aide de partenaires internationaux notamment l’UNESCO et l’ICA, la direction des archives de France et les Archives nationales de Tunisie. Elle explore aussi la façon dont les nouvelles technologies appliquées aux archives permettent aux chercheurs et aux citoyens d’y accéder. Elle présente l’organisation des archives courantes et intermédiaires dans les institutions qui s’est imposée comme un concept et une pratique depuis la création du Centre National des Archives. C’est autour de ses activités et de ses applications qu’ont été élaborées l’observation, l’enquête, la réflexion et certaines propositions. Les problématiques de la thèse s’articulent autour de cinq points : - L’histoire et l’organisation administrative du Yémen- La tradition archivistique au Yémen avant la réunification de 1990- Les origines et le développement du Centre national des archives (CNA)- Les missions, le fonctionnement et l’évaluation du CNA (de 1994 à aujourd’hui)- La fonction archives chez les producteurs (institutions gouvernementales)Les événements survenus au Yémen depuis 2011 ont malheureusement remis en cause toutes ces avancées. Ils ont tari les principales sources de financement de l’État et détruit une partie des fonds et des bâtiments, entraînant une paralysie complète du CNA. / For centuries, Yemeni institutions have not shown particular interest in their archives. The country was isolated from the outside world by British colonization in the South and the Ottoman occupation in the North. After the 1962 revolution, however, the need for organized and accessible archives has developed. This led to the creation in 1991 of the National Archives Centre (CNA). The Centre has improved the situation.This thesis aims at studying the interest shown by the Yemeni State in archival heritage. It starts with the history and the development of archives management in the ministries and governmental institutions of Yemen from the 1962 revolution to the current situation.It sheds light on the creation of the National Archives in Yemen and its international partnership with such institutions as UNESCO, ICA, French Directorate of Archives and Tunisian National Archives. It investigates the way new technologies are implemented in order to enable researchers and citizens to access to archives in a country such as Yemen. Moreover, it sheds light on the records management inside the Yemeni institutions. This practical has been commonly implemented since the creation of the National Archives Centre. This Centre has been the focus of this research. Suggestions are given for the development of its activities.Therefore, this thesis main topics are:- the history and administrative organization of Yemen ;- the archival practice and legacy in Yemen until the country’s reunification in 1990 ;- the origins and subsequent development of the National Archives Centre (CNA) ;- the CNA’s goals, functioning and assessment of its activities from 1994 up to nowadays ;- the archival functions in the producing governmental institutions.Events unfolding in Yemen since 2011 have challenged all these advances. The war did not only exhaust State’s funding. Warlike operations have also destroyed holdings and buildings, bringing the CNA to complete paralysis. This dissertation is concluded by an assessment of the archives current situation in Yemen. / ملخصلعدة قرون، لم يكن لدى اليمن أي مؤسسة أرشيفية، لأنها معزولة عن العالم الخارجي بسبب الاحتلال في شمال البلاد والاحتلال البريطاني في الجنوب. منذ ثورة 1962 ظهرت الحاجة إلى أرشيفات منظمة تنظيماً جيداً وسهل الوصول إليها، وقد أدى إنشاء المركز الوطني للوثائق (المركز الوطني للأرشيف) عام 1991 إلى تحسين الوضع إلى حد كبير.الهدف من هذه الرسالة هو دراسة اهتمام الدولة اليمنية للتراث الوثائقي والأرشيفي، وتشير الرسالة إلى تاريخ وتطور التوثيق والارشفة في الوزارات والمؤسسات الحكومية اليمنية منذ الثورة من عام 1962 وحتى اليوم. وكذلك تقدم إنشاء المركز الوطني للوثائق بمساعدة الشركاء الدوليين بما في ذلك اليونسكو والمجلس الدولي للأرشيف، إدارة الارشيف الفرنسي والأرشيف الوطني التونسي. وتدرس مدى تطبيق التكنولوجيا الجديدة على الارشيفات التي تمكن الباحثين والموطنين من الوصول إليها. وتعرض تنظيم الارشيف الجاري والوسيط في الوزارات والمؤسسات الحكومية التي ظهرت كمفهوم وممارسة منذ إنشاء المركز الوطني للوثائق. وحول نشاطاتها وتطبيقاتها التي وضعت للمراقبة والمسوحات الوثائقية والرؤية وبعض المقترحات لتنظيم الارشيف الجاري والوسيط. وتستند مشاكل ألأطروحة حول خمس نقاط : - التاريخ التنظيمي للإدارة ونشأت الارشيف في اليمن.- التقاليد الأرشيفية في اليمن قبل الوحدة عام 1990.- تأسيس وتطوير المركز الوطني للوثائق (cna).- مهام ونشاطات وتقييم المركز الوطني للوثائق (من 1994 إلى اليوم).- وظيفة الأرشيف لدى المنتجين للوثائق (المؤسسات الحكومية).وللأسف بأن الاحداث التي وقعت في اليمن منذ عام 2011 غيرت كل هذه التطورات في مجال الارشيف. لهذا جفت وقلت المصادر التمويل الحكومية وكذلك تدمير جزء من مبنى المركز وجزء من الرصيد الوثائقي فروع المركز بعدن وحضرموت وبعض ارشيفات الجهات والوزارات الحكومية، مما أدى الى شلل كامل للمركز الوطني للوثائق.الكلمات المفتاحية اليمن – الأرشيف – محفوظات – إدارة السجلات - تثمين - تشريعات الارشيف – تشريع المحفوظات - لوائح الارشيف - الارشيف العسكري – الأرشيف الجاري – الأرشيف الوسيط – الأرشيف التاريخي - المحفوظات الجارية - المحفوظات الوسيطة - المحفوظات التاريخية - - المركز الوطني للوثائق.

Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-09-26T18:46:21Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Ana Paula de Melo.pdf: 10485650 bytes, checksum: d1025152839f3e81b7418f9f33104bb2 (MD5) / Made available in DSpace on 2018-09-26T18:46:21Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Ana Paula de Melo.pdf: 10485650 bytes, checksum: d1025152839f3e81b7418f9f33104bb2 (MD5) Previous issue date: 2018-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta dissertação possui como tema as políticas de valorização docente, as quais envolvem, de maneira geral, a formação, as condições de trabalho, a carreira e a remuneração. Neste trabalho procuramos desvelar as particularidades escondidas no processo da formação inicial de professores. Assim, buscamos responder ao seguinte questionamento: quais os condicionantes sociais para a escolha da profissão docente tendo em vista o acesso e a permanência nas licenciaturas da Universidade Estadual de Ponta Grossa (UEPG)? Para tanto, objetivamos analisar os principais determinantes que levam os estudantes a escolher a profissão docente e suas influências nas condições de acesso e permanência nas licenciaturas da UEPG. Na busca por atender ao nosso objetivo, referenciamo-nos no aporte teórico metodológico marxista, o materialismo histórico-dialético. O instrumento de coleta de dados utilizado foi o questionário com 67 questões de múltipla escolha aplicado aos alunos das turmas dos quartos anos das licenciaturas da UEPG, em 2017, sendo pesquisados os cursos de licenciatura em Artes visuais, Ciências Biológicas, Educação Física, Física, Geografia, História, Letras Português/Inglês, Matemática, Música, Pedagogia e Química. Foram contemplados, no questionário, os aspectos socioeconômicos, institucionais, familiares e pessoais dos licenciandos. Em 2018, realizamos entrevistas semiestruturadas com seis egressos oriundos das licenciaturas em que aplicamos o questionário, com a intenção de aprofundar algumas questões desse instrumento. De acordo com as informações obtidas, a maioria dos licenciandos é trabalhador, oriundo da educação básica pública, com renda mensal familiar de até três salários mínimos, já pensou em desistir ou trancar o curso, sente a necessidade de auxílio estudantil, principalmente em relação ao transporte e à alimentação. Dessa maneira, consideramos que a organização precária do trabalho, na sociedade capitalista, gera, por sua vez, uma precarização na formação do trabalhador. Por isso, entendemos que a escolha pela docência e o acesso à educação superior são condicionados, principalmente, pela necessidade de trabalhar, e a permanência só é possível devido à conciliação do trabalho com a graduação. Dessa forma, o mesmo elemento – trabalho– que possibilita a permanência do estudante, pode desqualificar a sua formação e levá-lo à evasão. Por isso, ser trabalhador, cursar uma licenciatura e se formar professor, é um ato de resignação e resistência ao capital. Resignação porque a opção pelo magistério e o acesso ao curso superior se dão de acordo com as possibilidades oferecidas pelo capital. Resistência porque ser trabalhador, com condições socioeconômicas desfavoráveis e, ao mesmo tempo, ser estudante, é ir contra a perspectiva de que os trabalhadores devem trabalhar somente para reproduzir sua força de trabalho. Pretendemos contribuir com o estudo realizado, dentro das possibilidades oferecidas na busca pela emancipação política, por meio do conhecimento da realidade que perpassa a formação inicial dos professores da UEPG, de maneira a auxiliar na transformação dessa realidade, com políticas que atendam às demandas apresentadas neste trabalho. Porém, sem perder de vista que somente por meio da emancipação humana é que poderemos, verdadeiramente, libertar-nos dos entraves impostos pelo capital, nos mais diversos aspectos da vida humana. / This dissertation’s main theme is teacher’s valorization policies, which involve primarily teachers training, work conditions, career and remuneration. Along the text, we seek to unveil the hidden specificities in the initial teachers training process. Therefore, we aim to answer the following question: which are the social conditioners for the teacher’s career choice, in view of the access and permanence in the graduations within teacher preparation program at the State University of Ponta Grossa (UEPG)? On that account, we objectively analyze the main determinants that guide the students to choose the teaching career and their influences in the access and permanence conditions in these graduations. In the path to reach our aim, we look for the Marxist methodologic theory, the dialectical and historical materialism. To collect data, we applied a 67 objective questions questionnaire to the students of the senior year (4th) of 2017 in the following courses: Visual Arts, Biological Sciences, Physical Education, Physics, Geography, History, English Language and its Literature, Mathematics, Music, Pedagogy and Chemistry. In the questionnaire the socio-economical, institutional, familiar and personal aspects were taken into account. In 2018, semi-structured interviews were held within six university egresses from the same courses the questionnaire was applied, aiming to depth some aspects of this collecting tool. According to the data, most of the students are working people, from the public system of elementary education and high school, with family income until three Brazilian minimum wage, have had thoughts of giving up their graduation and felt/feel the need of student assistance, mostly related to transport and feeding. Thus, considering that the work precarious organization in the capitalist society in its turn creates the precariousness in the workers training/preparing programs. Hence, we understand that the teacher career choice and the graduation access are conditioned mostly by the need to work. The permanence is only possible due to the conciliation of work and graduation. That being the case working is the element for both allowing the student to stay in their course and disqualify its development, as well as the reason for them to leave. Therefore, working, studying and becoming a teacher is a resignation and resistant act towards the capital. Resistant because being a working person within unwealthy socio-economical conditions as well as a student goes against the perspective that working people should only work to reproduce the workforce. With this research, we pretend to contribute within the political emancipation through the knowledge of the reality that follows the initial teacher preparation program at UEPG, as so we can change this reality with policies that meet the demands here presented. Yet, not having out of sight that only by human emancipation we truly can free ourselves from the barriers imposed by the capital in all the different aspects of life.

La meta de esta tesis es impulsar las tendencias de desarrollo de la industria química que promueven la sostenibilidad de la misma. El objetivo es un control integrado de la contaminación que permita reducir las emisiones a fin de promover las actividades de producción sostenibles.En este sentido, el tratamiento de efluentes industriales con fluoruros consiste en una precipitación química. Sin embargo, el proceso genera elevadas cantidades de lodos con elevada humedad y bajo riqueza en fluoruro cálcico, por lo que su reutilización en la fabricación de HF no es viable técnica y económicamente.En esta tesis se presenta la recuperación de fluoruros de aguas industriales fluoradas mediante cristalización en un reactor de lecho fluidizado. Las principales ventajas de esta tecnología respecto del tratamiento convencional son la no generación de lodos, la reducción de residuos y la recuperación de fluoruro para su posterior valorización. / The aim of this thesis is to support the trends of the chemical industry development that promote sustainability. The goal is an integrated pollution control to reduce the emissions in order to promote sustainable production activities.In this sense, the common methods for fluoride removal from industrial wastewater involve chemical precipitation. The process generates large amounts of a water rich sludge requiring disposal with increasing costs. Due to the high water content and the low quality of the sludge, reuse of fluoride is not an economical option. The removal of fluoride in a fluidized bed reactor by crystallization has been presented in this thesis as an alternative to the chemical precipitation. When it is compared with the conventional precipitation process, the major advantage of this new clean technology is the elimination of sludge formation, the materials recovery and the reduction of solid waste.

In settings such as hotels, bars and boutiques, things like cars, sodas, clothes, and cities, are fueled with the symbolic capital of graffiti. The purpose of this ethnographic study is to understand how graffiti writers, through marketing, increase the value of their work, as well as that of other products, and how this commercialization affects the meaning of graffiti.  Utilizing a perspective of social constructionism, the analysis shows how actors and social fields that are constructed as incongruous (e.g., art galleries and graffiti culture), are at the same time being mixed together to create something new, and thus create value. This study shows how practices that are considered marginal, or deviant, at the same time generate value within the general economy. Deploying an abductive approach, and building on ample empirical material, this study shows that the narrative of graffiti as something illegal is one of the main traits that enables graffiti writers to exchange subcultural capital for economic. The results show that previous research, investigating graffiti from a dichotomous perspective of either art or vandalism, do not give a satisfactory understanding of this diverse subculture.   The empirical material consists of 30 participant observations in public events, in Sweden during the autumn of 2014, where graffiti is turned into a commodity embodied with subcultural capital. Moreover, four in-depth interviews were executed with graffiti writers who have sold their competence and art for purposes of marketing, and one group interview with three of their customers. Further, several documents were collected and analyzed.

Les fumées à basse température (<120-150 °C) sortant des procédés industriels pourraient être récupérées pour la production d'électricité et constituent un moyen efficace de réduction de la consommation d'énergie primaire et des émissions de dioxyde de carbone. Cependant, des barrières techniques tels que la faible efficacité de conversion, la nécessité d'une grande zone de transfert de chaleur, et la présence de substances chimiques corrosives liées à une forte teneur en humidité lors du fonctionnement en environnement sévère entravent leur application plus large. Cette thèse porte particulièrement sur les secteurs industriels les plus énergivores rencontrant actuellement des difficultés à récupérer l'énergie des sources de chaleur à basse température dans des environnements hostiles. Des cycles thermodynamiques existants basés sur le Cycle de Rankine Organique (ORC) sont adaptés et optimisés pour ce niveau de température. Deux méthodes de récupération de chaleur classiques sont étudiées plus particulièrement : les déshumidifications à contact direct et indirect. Des méthodes de conception optimisées pour les échangeurs de chaleur sont élaborées et validées expérimentalement. Pour la déshumidification à contact indirect, des matériaux à revêtement anticorrosifs sont proposés et testés. Pour la déshumidification à contact direct, les effets du type et de la géométrie des garnissages sur les performances hydrauliques sont étudiés. Des cycles thermodynamiques innovants basés sur la technologie de déshydratation liquide sont proposés. Un cycle de régénération amélioré (IRC) est développé. Comparé aux technologies de récupération de chaleur classiques, l'IRC proposé améliore à la fois la puissance nette et le taux de détente de la turbine en prévenant par ailleurs les problèmes de corrosion. / Low-temperature waste-gas heat sources (< 120-150°C) exiting several industrial processes could be recovered for electricity production and constitute an effective mean to reduce primary energy consumption and carbon dioxide emissions. However, technical barriers such as low conversion efficiency, large needed heat transfer area, and the presence of chemically corrosive substances associated with high moisture content when operating in harsh environment impede their wider application. This thesis focuses on particularly energy-hungry industrial sectors characterized by presently unsolved challenges in terms of environmentally hostile low-temperature heat sources. Existing thermodynamic cycles based on Organic Rankine Cycle (ORC) are adapted and optimized for this temperature level. Two conventional heat recovery methods are studied more particularly: indirect and direct contact dehumidification. Optimized design methods for heat exchangers are elaborated and experimentally validated. For the indirect contact dehumidification, advanced anti-corrosion coated materials are proposed and laboratory tested. For the direct contact dehumidification, the effects of packing material and geometry on the corresponding hydraulic performances are underlined. Innovative thermodynamic cycles based on the liquid desiccant technology are investigated. An improved regeneration cycle (IRC) is developed. Compared to the conventional heat recovery technologies, the proposed “IRC” improves both net power and turbine expansion ratio besides preventing faced corrosions problems.