Procesos de configuración simbiótica entre pictogramas y tipografía

315 p.

Advanced Reaction Systems for Hydrogen Production

[EN] This PhD work started in March 2010 with the support of the University of the Basque Country (UPV/EHU) under the program named “Formación de Personal Investigador” at the Chemical and Environmental Engineering Department in the Faculty of Engineering of Bilbao. The major part of the Thesis work was carried out in the mentioned department, as a member of the Sustainable Process Engineering (SuPrEn) research group. In addition, this PhD Thesis includes the research work developed during a period of 6 months at the Institut für Mikrotechnik Mainz GmbH, IMM, in Germany. During the four years of the Thesis, conventional and microreactor systems were tested for several feedstocks renewable and non-renewable, gases and liquids through several reforming processes in order to produce hydrogen. For this purpose, new catalytic formulations which showed high activity, selectivity and stability were design. As a consequence, the PhD work performed allowed the publication of seven scientific articles in peer-reviewed journals. This PhD Thesis is divided into the following six chapters described below. The opportunity of this work is established on the basis of the transition period needed for moving from a petroleum based energy system to a renewable based new one. Consequently, the present global energy scenario was detailed in Chapter 1, and the role of hydrogen as a real alternative in the future energy system was justified based on several outlooks. Therefore, renewable and non-renewable hydrogen production routes were presented, explaining the corresponding benefits and drawbacks. Then, the raw materials used in this Thesis work were described and the most important issues regarding the processes and the characteristics of the catalytic formulations were explained. The introduction chapter finishes by introducing the concepts of decentralized production and process intensification with the use of microreactors. In addition, a small description of these innovative reaction systems and the benefits that entailed their use were also mentioned. In Chapter 2 the main objectives of this Thesis work are summarized. The development of advanced reaction systems for hydrogen rich mixtures production is the main objective. In addition, the use and comparison between two different reaction systems, (fixed bed reactor (FBR) and microreactor), the processing of renewable raw materials, the development of new, active, selective and stable catalytic formulations, and the optimization of the operating conditions were also established as additional partial objectives. Methane and natural gas (NG) steam reforming experimental results obtained when operated with microreactor and FBR systems are presented in Chapter 3. For these experiments nickel-based (Ni/Al2O3 and Ni/MgO) and noble metal-based (Pd/Al2O3 and Pt/Al2O3) catalysts were prepared by wet impregnation and their catalytic activity was measured at several temperatures, from 973 to 1073 K, different S/C ratios, from 1.0 to 2.0, and atmospheric pressure. The Weight Hourly Space Velocity (WHSV) was maintained constant in order to compare the catalytic activity in both reaction systems. The results obtained showed a better performance of the catalysts operating in microreactors. The Ni/MgO catalyst reached the highest hydrogen production yield at 1073 K and steam-to-carbon ratio (S/C) of 1.5 under Steam methane Reforming (SMR) conditions. In addition, this catalyst also showed good activity and stability under NG reforming at S/C=1.0 and 2.0. The Ni/Al2O3 catalyst also showed high activity and good stability and it was the catalyst reaching the highest methane conversion (72.9 %) and H2out/CH4in ratio (2.4) under SMR conditions at 1073 K and S/C=1.0. However, this catalyst suffered from deactivation when it was tested under NG reforming conditions. Regarding the activity measurements carried out with the noble metal-based catalysts in the microreactor systems, they suffered a very quick deactivation, probably because of the effects attributed to carbon deposition, which was detected by Scanning Electron Microscope (SEM). When the FBR was used no catalytic activity was measured with the catalysts under investigation, probably because they were operated at the same WHSV than the microreactors and these WHSVs were too high for FBR system. In Chapter 4 biogas reforming processes were studied. This chapter starts with an introduction explaining the properties of the biogas and the main production routes. Then, the experimental procedure carried out is detailed giving concrete information about the experimental set-up, defining the parameters measured, specifying the characteristics of the reactors used and describing the characterization techniques utilized. Each following section describes the results obtained from activity testing with the different catalysts prepared, which is subsequently summarized: Section 4.3: Biogas reforming processes using γ-Al2O3 based catalysts The activity results obtained by several Ni-based catalysts and a bimetallic Rh-Ni catalyst supported on magnesia or alumina modified with oxides like CeO2 and ZrO2 are presented in this section. In addition, an alumina-based commercial catalyst was tested in order to compare the activity results measured. Four different biogas reforming processes were studied using a FBR: dry reforming (DR), biogas steam reforming (BSR), biogas oxidative reforming (BOR) and tri-reforming (TR). For the BSR process different steam to carbon ratios (S/C) from 1.0 to 3.0, were tested. In the case of BOR process the oxygen-to-methane (O2/CH4) ratio was varied from 0.125 to 0.50. Finally, for TR processes different S/C ratios from 1.0 to 3.0, and O2/CH4 ratios of 0.25 and 0.50 were studied. Then, the catalysts which achieved high activity and stability were impregnated in a microreactor to explore the viability of process intensification. The operation with microreactors was carried out under the best experimental conditions measured in the FBR. In addition, the physicochemical characterization of the fresh and spent catalysts was carried out by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), N2 physisorption, H2 chemisorption, Temperature Programmed Reduction (TPR), SEM, X-ray Photoelectron Spectroscopy (XPS) and X-ray powder Diffraction (XRD). Operating with the FBR, conversions close to the ones predicted by thermodynamic calculations were obtained by most of the catalysts tested. The Rh-Ni/Ce-Al2O3 catalyst obtained the highest hydrogen production yield in DR. In BSR process, the Ni/Ce-Al2O3 catalyst achieved the best activity results operating at S/C=1.0. In the case of BOR process, the Ni/Ce-Zr-Al2O3 catalyst showed the highest reactants conversion values operating at O2/CH4=0.25. Finally, in the TR process the Rh-Ni/Ce-Al2O3 catalyst obtained the best results operating at S/C=1.0 and O2/CH4=0.25. Therefore, these three catalysts were selected to be coated onto microchannels in order to test its performance under BOR and TR processes conditions. Although the operation using microreactors was carried out under considerably higher WHSV, similar conversions and yields as the ones measured in FBR were measured. Furthermore, attending to other measurements like Turnover Frequency (TOF) and Hydrogen Productivity (PROD), the values calculated for the catalysts tested in microreactors were one order of magnitude higher. Thus, due to the low dispersion degree measured by H2-chemisorption, the Ni/Ce-Al2O3 catalyst reached the highest TOF and PROD values. Section 4.4: Biogas reforming processes using Zeolites L based catalysts In this section three type of L zeolites, with different morphology and size, were synthesized and used as catalyst support. Then, for each type of L zeolite three nickel monometallic and their homologous Rh-Ni bimetallic catalysts were prepared by the wetness impregnation method. These catalysts were tested using the FBR under DR process and different conditions of BSR (S/C ratio of 1.0 and 2.0), BOR (O2/CH4 ratio of 0.25 and 0.50) and TR processes (at S/C=1.0 and O2/CH4=0.25). The characterization of these catalysts was also carried out by using the same techniques mentioned in the previous section. Very high methane and carbon dioxide conversion values were measured for almost all the catalysts under investigation. The experimental results evidenced the better catalytic behavior of the bimetallic catalysts as compared to the monometallic ones. Comparing the catalysts behavior with regards to their morphology, for the BSR process the Disc catalysts were the most active ones at the lowest S/C ratio tested. On the contrary, the Cylindrical (30–60 nm) catalysts were more active under BOR conditions at O2/CH4=0.25 and TR processes. By the contrary, the Cylindrical (1–3 µm) catalysts showed the worst activity results for both processes. Section 4.5: Biogas reforming processes using Na+ and Cs+ doped Zeolites LTL based catalysts A method for the synthesis of Linde Type L (LTL) zeolite under microwave-assisted hydrothermal conditions and its behavior as a support for heterogeneously catalyzed hydrogen production is described in this section. Then, rhodium and nickel-based bimetallic catalysts were prepared in order to be tested by DR process and BOR process at O2/CH4=0.25. Moreover, the characterization of the catalysts under investigation was also carried out. Higher activities were achieved by the catalysts prepared from the non-doped zeolites, Rh-Ni/D and Rh-Ni/N, as compared to the ones supported on Na+ and Cs+ exchanged supports. However, the differences between them were not very significant. In addition, the Na+ and Cs+ incorporation affected mainly to the Disc catalysts. Comparing the results obtained by these catalysts with the ones studied in the section 4.4, in general worst results were achieved under DR conditions and almost the same results when operated under BOR conditions. In Chapter 5 the ethylene glycol (EG) as feed for syngas production by steam reforming (SR) and oxidative steam reforming (OSR) was studied by using microchannel reactors. The product composition was determined at a S/C of 4.0, reaction temperatures between 625°C and 725°C, atmospheric pressure and Volume Hourly Space Velocities (VHSV) between 100 and 300 NL/(gcath). This work was divided in two sections. The first one corresponds to the introduction of the main and most promising EG production routes. Then, the new experimental procedure is detailed and the information about the experimental set-up and the measured parameters is described. The characterization was carried out using the same techniques as for the previous chapter. Then, the next sections correspond to the catalytic activity and catalysts characterization results. Section 5.3: xRh-cm and xRh-np catalysts for ethylene glycol reforming Initially, catalysts with different rhodium loading, from 1.0 to 5.0 wt. %, and supported on α-Al2O3 were prepared by two different preparation methods (conventional impregnation and separate nanoparticle synthesis). Then, the catalysts were compared regarding their measured activity and selectivity, as well as the characterization results obtained before and after the activity tests carried out. The samples prepared by a conventional impregnation method showed generally higher activity compared to catalysts prepared from Rh nanoparticles. By-product formation of species such as acetaldehyde, ethane and ethylene was detected, regardless if oxygen was added to the feed or not. Among the catalysts tested, the 2.5Rh-cm catalyst was considered the best one. Section 5.4: 2.5Rh-cm catalyst support modification with CeO2 and La2O3 In this part of the Chapter 5, the catalyst showing the best performance in the previous section, the 2.5Rh-Al2O3 catalyst, was selected in order to be improved. Therefore, new Rh based catalysts were designed using α-Al2O3 and being modified this support with different contents of CeO2 or La2O3 oxides. All the catalysts containing additives showed complete conversion and selectivities close to the equilibrium in both SR and OSR processes. In addition, for these catalysts the concentrations measured for the C2H4, CH4, CH3CHO and C2H6 by-products were very low. Finally, the 2.5Rh-20Ce catalyst was selected according to its catalytic activity and characterization results in order to run a stability test, which lasted more than 115 hours under stable operation. The last chapter, Chapter 6, summarizes the main conclusions achieved throughout this Thesis work. Although very high reactant conversions and rich hydrogen mixtures were obtained using a fixed bed reaction system, the use of microreactors improves the key issues, heat and mass transfer limitations, through which the reforming reactions are intensified. Therefore, they seem to be a very interesting and promising alternative for process intensification and decentralized production for remote application.

Modelización de procesos hidrológicos y de contaminación por nitratos mediante dos códigos numéricos (SWAT y MOHID). Cuenca agrícola del río Alegría (País Vasco)

245 p.+ anexos

La frontera, borders an transborders. Reflections of the borderlands in Chicana Literature (early 20th-21st c.)

421 p.

Nos bastidores da criação da Comissão Nacional de Energia Nuclear: disputas políticas e interesses econômicos

O objetivo desta dissertação de mestrado é analisar o processo de criação e regulamentação da Comissão Nacional de Energia Nuclear (CNEN), desde o governo Juscelino Kubitschek (1956-1961) até sua efetiva regulamentação em 1962. A iniciativa inscreveu-se no conjunto de medidas visando dar solução à crise que atravessava o Conselho Nacional de Pesquisas (CNPq), e que levariam à instauração, na Câmara dos Deputados, em 1956, de Comissão Parlamentar de Inquérito para investigar o problema da energia atômica no país. Como sinônimo de desenvolvimento e progresso, a energia nuclear também seria incluída no Programa de Metas de JK. São investigadas as disputas políticas e os interesses econômicos que marcaram o processo de implantação da CNEN e o desenvolvimento de suas atividades na etapa inicial de seu funcionamento.

Procesos microevolutivos en poblaciones de Sudamérica

308 p.

Conexiones entre la pintura abstracta y la naturaleza: formas, procesos, funciones y estrategias. Análisis y desarrollo experimental

674 p.

Diseño y fabricación de un conjunto de estriberas y semimanillares para moto de competición.

[ES]El objeto del presente trabajo consiste en diseñar un conjunto de estriberas y semimanillares para una moto de competición, que cumplan con una serie de requerimientos geométricos y que garanticen las mejores prestaciones posibles en cuanto a competición, entre las que destacan la seguridad y comodidad del piloto. A continuación se procederá a elegir los procesos más adecuados para la fabricación de los mismos, teniendo en cuenta requisitos económicos y de calidad, para sacar al mercado un producto lo más competitivo posible. El estudio se basa principalmente en el análisis de diferentes alternativas que se pueden adoptar para obtener el diseño de los productos y posterior fabricación. Para ello se estudiarán los objetivos y condiciones que se deben cumplir. Cabe destacar que la idea de desarrollo de este proyecto surgió dentro de otro de mayor envergadura, la competición MotoStudent. MotoStudent es una competición internacional entre universidades de todo el mundo en la que los equipos de estudiantes se enfrentan al desafío de diseñar y desarrollar un prototipo de motocicleta de competición similar a la categoría mundialista de Moto3.

Sistemas económicos: variedades de capitalismo.Planificación en las Economías de la OCDE entre 1945 y 1973/Las Economías de Mercado con Planificación indicativa.

[ES] Este trabajo expone en qué consistió y qué importancia económica y organizativo-administrativa tuvo la denominada planificación indicativa, en los países de la OCDE, en el periodo 1945-1973. Si el empleo de la planificación indicativa es un rasgo común y relevante en casi todos estos países, durante ese periodo, esa institución por sí sola podría servir para establecer la existencia de una variedad diferenciada y significativa del sistema económico capitalista o de economía de mercado: las economías de mercado con planificación indicativa. Además se presentarán los motivos que explican el surgimiento y desaparición de esta institución en esos países y los resultados obtenidos.

La migración transnacional y los procesos de integración en las sociedades de destino. Una mirada a la población colombiana residente en la Comunidad Autónoma del País Vasco

411 p.

Optimización de procesos de recubrimiento para herramientas de corte. Tecnologías de recubrimiento, métodos de caracterización y optimización de las propiedades

249 p.

Del diseño a la programación de sistemas de control para la automatización de procesos industriales basados en PLC`s

Actualmente las mayoría de sistemas de automatización industrial utilizan los Autómatas Programables (PLC - Programmable Logic Controller) como sistemas de control y el diseño de dicho sistema se realiza mediante el lenguaje de modelado Grafcet. SFCEdit es un editor de Grafcet que permite el diseño de estos sistemas de control y la exportación de los mismos en un formato XML. Resumen Por otra parte tenemos la norma IEC 61131-3 que busca estandarizar los lenguajes de programación de los PLC de esta manera no se tendría que usar un lenguaje distinto por cada fabricante, y la organización PLCOpen rigiéndose por la norma ha creado un formato XML para cada lenguaje, en los cuales se basa el traductor. Resumen Habitualmente el paso del diseño a la programación se realiza de forma manual. La automatización de este proceso es el objetivo general del proyecto realizado. En esté se ha desarrollado una herramienta que permite realizar la traducción del diseño gráfico al estándar IEC 61131-3 considerando las particularidades de algunos fabricantes de PLCs como Beckhoff (TwinCAT) y TSX Micro (PL7Pro). Además la herramienta realiza la traducción al formato XML de PLCOpen. Resumen El traductor funciona recibiendo un fichero XML (exportado de SFCEdit) procesa su información y genera los ficheros en función de la compatibilidad que el usuario seleccione.

El desafío de exponer: procesos y retos museográficos

Il y a aussi des chapitres en français. There are also chapters in English. Cap. 1. El complicado arte de exponer. Iñaki Arrieta Urtizberea. Cap. 2. “Esta exposición no es para este museo”. Las salas permanentes del Museu Valencià d’Etnologia. Joan Segui. Cap. 3. Debunking, Decentralizing and Dissonance: Cultural Jamming @ Museum of Vancouver. Viviane Gosselin. Cap. 4. L’exposition des objets de cultures autochtones aujourd’hui, gain ou perte de sens? Le cas de l’exposition « C’est notre histoire... » au Musée de la civilisation de Québec. Daniel Arsenault et Nadine Desbiens. Cap. 5. El Born de Barcelona: exposiciones conmemorativas, límites, problemas y desafíos. Francesc Xavier Hernàndez Cardona. Cap. 6. Silencios y omisiones: narrando y exhibiendo la historia nacional. Magdalena Mieri. Cap. 7. Exhibiting the Commons. The Case of Tensta konsthall. Haizea Barcenilla Garcia. Cap. 8. Interactividad y patrimonio. Retos, tendencias y líneas de futuro. Núria Serrat Antolí.

Control de procesos aterogénicos

La aterosclerosis es una enfermedad inflamatoria crónica caracterizada por una acumulación anormal de lípidos en la íntima de las arterias de tamaño mediano y superior, la cual implica una oclusión progresiva de las mismas provocando la aparición de diferentes enfermedades cardiovasculares y en muchos de los casos, la muerte. Debido al aumento progresivo de estas enfermedades es necesario establecer nuevas estrategias terapéuticas, lo cual requiere un conocimiento más exhaustivo de los mecanismos moleculares implicados en las enfermedades cardiovasculares.

Política criminal e direito penal econômico: um estudo interdisciplinar dos crimes econômicos e tributários

Este trabalho toma como objeto o Direito Penal Econômico em perspectiva interdisciplinar, no contexto da Constituição da República e, portanto, do Estado Democrático de Direito. Os propósitos são os seguintes: Analisar os vínculos entre modelo sócio-econômico, política criminal e paradigma punitivo. Identificar perspectivas do Direito Penal Econômico, no cenário contemporâneo de sociedade de risco. Examinar pressupostos, vertentes e abordagem do Direito Penal Tributário, com enfoque na abordagem social do bem jurídico tributário, do delito fiscal, da lavagem de dinheiro, na esteira dos crimes do colarinho branco. Do ponto de vista metodológico, desenvolveu-se pesquisa descritiva, baseada no modelo crítico-dialético, apoiada no pressuposto de que a trajetória do Direito Penal e sua inserção na seara econômica e tributária acompanham as contradições e valores sócio-filosóficos dominantes na sociedade. Nesse passo, com base na doutrina, legislação e jurisprudência nacional e estrangeira, procede-se à releitura do Direito Penal Econômico, a partir da Constituição e do modelo de Estado Social, que admite a intervenção no domínio econômico, no intuito de promover a justiça social. Além disso, procede-se à análise de sistemas penais de diversos países, para verificar, no cenário da globalização econômica e da aproximação das questões relacionadas à delinquência econômica, como são enfrentados problemas relacionados à configuração, à persecução e a punição de tais delitos. A conclusão aponta para a necessidade de construção de uma Política Criminal do Direito Penal Econômico que tome em consideração variáveis relacionadas à Economia e aos Princípios do Direito Penal, de molde a promover ajustamento do sistema penal aos valores e princípios constitucionais, promovendo o equilíbrio entre interesses individuais e coletivos.