This thesis focuses on the changed governance of the public sector and what it can entail for professional work in substance abuse treatment. The point of departure is one of these new forms of governing, namely ‘knowledge governance’, which refers to a policy-driven process for promoting the use of evidence-based practice.  The overall aim is to contribute to understanding and knowledge of the meaning and the conditions for knowledge governance in substance abuse treatment. The thesis studies how knowledge is interpreted by professionals and adapted to local practice in relation to organizational and professional conditions. The thesis also highlights the implications that   these conditions may have for knowledge development on a professional and organizational level. The empirical material comprises three studies. Study 1 included a document analysis and a literature review. The document analysis examines how knowledge governance is described in official documents, while the focus of the literature review is on the concept of knowledge management. In Studies 2 and 3 focus group interviews were conducted with professionals who participated in a specific project, and professionals who use structured interview methods in their work (Addiction Severity Index, ASI, or Documentation of clients, DOC). The theoretical perspectives used in the thesis are neo-institutional theory, professional theory and perspectives on workplace learning.   The results of Study 1 showed that knowledge governance embodies a steering of organizations, in comparison with knowledge management as a means for steering in organizations. The analyses from the focus group interviews demonstrate that knowledge governance becomes the subject of translations and edits to a local context. This process was affected by both organizational and professional conditions. The thesis is concluded with a discussion of the conditions that must be present if knowledge governance can lead to development of knowledge. The main result is that strategies must be tailored to each organization's specific condition and must be anchored throughout the organization.

Arctic rivers transport 31-42 Tg organic carbon (OC) each year to the Arctic Ocean, which is equal to 10% of the global riverine OC discharge. Since the Arctic Ocean only holds approximately 1% of the global ocean volume, the influence of terrestrially derived organic carbon (OCter) in the Arctic Ocean is relatively high. Despite the global importance of this region the behavior of the, by far largest fraction of the OCter, the dissolved organic carbon (DOC) in Arctic and sub-arctic estuaries is still a matter of debate. This thesis describes data originating from field cruises in Arctic and sub-arctic estuaries and coastal areas with the aim to improve the understanding of the fate of OCter in these areas, with specific focus on DOC. All presented studies indicate that DOCter and terrestrially derived particulate organic carbon (POCter) are subjected to substantial degradation in high-latitude estuaries, as shown by the non-conservative behavior of DOC in the East Siberian Arctic Shelf Seas (ESAS) (paper I) and the even more rapid degradation of POC in the same region (paper II). The removals of OCter in Arctic shelf seas were further supported by multiple isotope studies (paper III and IV), which showed that a use of 13C/12C in both OC and DIC, together with 34S/32S is a powerful tool to describe the sources and fate of OCter in estuaries and coastal seas. High-latitude estuaries play a key role in the coupling between terrestrial and marine carbon pools. In contrast to the general perception, this thesis shows that they are not only transportation areas for DOCter from rivers to the ocean, but are also active sites for transformation, degradation and sedimentation of DOCter, as well as for POCter. In a rapidly changing climate, the importance of these areas for the coupling between inorganic and organic carbon pools cannot be underestimated. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In press. Paper 2: Submitted. Paper 4: Manuscript.</p>

The trophic state of lakes is commonly defined by the concentration of nutrients in the water column. High nutrient concentrations generate high phytoplankton production, and lakes with low nutrient concentrations are considered low-productive. This simplified view of lake productivity ignores the fact that benthic primary producers and heterotrophic bacteria can be important basal producers in lake ecosystems. In this thesis I have studied clear-water and brown-water lakes with respect to primary production, respiration and bacterial production based on allochthonous organic carbon. These processes were quantified in pelagic and benthic habitats on temporal and spatial scales. I also calculated the net ecosystem production of the lakes, defined as the difference between gross primary production (GPP) and respiration (R). The net ecosystem production indicates whether a lake is net heterotrophic (GPP &lt; R), net autotrophic (GPP &gt; R) or in metabolic balance (GPP = R). Net heterotrophic lakes are sources of carbon dioxide (CO2) to the atmosphere since respiration in these lakes, by definition, is subsidized by an external organic carbon source. External organic carbon is transported to lakes from the terrestrial environment via inlets, and can serve as a carbon source for bacteria but it also limits light availability for primary producers by absorbing light. On a seasonal scale, four of the clear-water lakes studied in this thesis were dominated by primary production in the soft-bottom benthic habitat and by respiration in the pelagic habitat. Concentrations of dissolved organic carbon (DOC) were low in the lakes, but still high enough to cause the lakes to be net heterotrophic. However, the lakes were not low-productive due to the high production in the benthic habitat. One of the clear-water lakes was studied also during the winter and much of the respiration under ice was supported by the benthic primary production from the previous summer. This is in contrast to brown-water lakes where winter respiration is suggested to be supported by allochthonous organic carbon. By studying lakes in a DOC gradient (i.e. from clear-water to brown-water lakes) I could draw two major conclusions. The lakes became less productive since benthic primary production decreased with increasing light extinction, and the lakes became larger sources of CO2 to the atmosphere since pelagic respiration was subsidized by allochthonous organic carbon. Thus, lake carbon metabolism can have an important role in the global carbon cycle due to their processing of terrestrial organic carbon and to their possible feedback effects on the climate system.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-09-06T22:16:58Z No. of bitstreams: 1 DISSERTA??O FINAL - AP?S DEFESA ELCI.pdf: 2234862 bytes, checksum: 49c6a6cd6ce69b00744beb523841413e (MD5) / Made available in DSpace on 2016-09-06T22:16:58Z (GMT). No. of bitstreams: 1 DISSERTA??O FINAL - AP?S DEFESA ELCI.pdf: 2234862 bytes, checksum: 49c6a6cd6ce69b00744beb523841413e (MD5) Previous issue date: 2016-04-18 / This text, written during a research developed in the Graduate Program in Education at the UnivesidadeEstadual de Feira de Santana - Bahia, aims to understandthe contribution of the Teaching Internship for pedagogic training of teachers of Higher Educationthrough the representations of students of the Community Health Master. It was certified that the curricular component Teaching Internship is an important education environment of the future university professor, locus in which students of the Graduate Program strictosensuacquire some of the knowledge needed for teaching practice. However, it is worth noting that teaching learning extends throughout one?s whole career. To achieve the established objective, we conducted a descriptive qualitative research, which was based on principles of the Social Representations Theory ? SRT (MOSCOVICI, 2003a, 2003b; JODELET, 1989, 2001 e 2007). Regarding the production of data, it was held a documentary analysis(TRIVI?OS, 1987) of the regiment and of the pedagogic proposal of the Graduate Community Health Program at UEFS. It was also used semi structured interviews (MINAYO, 2006), which were carried out with 12 students from the Academic Master of the aforementioned Program. In order to analyze the data produced in the research some principles of Content Analysis(BARDIN, 2011) were used. In the discussion of the data produced five categories were identified, as follows: the first refers to the concept of teaching internship; in the second, the knowledge necessary for university teaching is discussed; in the third was verified which were the contributions of the internship to university teaching; in the fourth the process of the Teaching Internship experience was described and, finally, in the fifth category, where suggestions to improve the experience of Teaching Internship were presented by our contributors. The main conclusions of this research focus that the internship contributes to the preparation of graduate students for university teaching and for the development of teacher identity. Moreover, it contributes to this preparation for the acquisition of knowledge of the reality of university classroom, for the exchange of knowledge with the experienced teacher and, finally, for the perception of the master students on the human condition of the teaching profession and the humanization in the relationships that occur in the educational context.In addition to these contributions, our contributors address the need for the Community Health Program not prioritizing specific studies and research training at the expense of teacher training, given the complexity of teaching today, which requires special attention.Participants also emphasized the prevalence of the following difficulties during the Teaching Internship experience: the absence of an effective interaction between the Undergraduate and Graduate programs, structural and political problems that damaged the internship. In addition to this, the students had difficulties in understanding the importance of courses in their training, didactic and pedagogical difficulties of interns to conduct the courses and embarrassments of master students to assess and deal with the graduate students taking the course again after failing. Furthermore, our study confirmed the need to implement institutional policies for the formation of the university teacher, especially with beginning teachers who are in a period of adaptation and professional learning and also with experienced teachers to reflect on their teachingpractices continuously so they can update and innovate their practices. / Este texto dissertativo, elaborado durante uma investiga??o desenvolvida no Programa de P?s-Gradua??o em Educa??o da Universidade Estadual de Feira de Santana ? Bahia, tem por objetivo compreender, mediante as representa??es de estudantes do Mestrado de Sa?de Coletiva, a contribui??o do Est?gio Doc?ncia para a forma??o pedag?gica de professores da Educa??o Superior. Certificamos que o componente curricular Est?gio Doc?ncia ? um importante espa?o de forma??o do futuro docente universit?rio, l?cus em que os estudantes da P?s-Gradua??o stricto sensu apreendem alguns saberes necess?rios para a pr?tica docente, entretanto ? relevante destacar que a aprendizagem da doc?ncia se estende por toda sua carreira. Para alcan?armos o objetivo tra?ado, realizamos uma pesquisa do tipo qualitativa, de car?ter descritivo, que se fundamentou em princ?pios da Teoria das Representa??es Sociais ? TRS (MOSCOVICI, 2003a, 2003b; JODELET, 1989, 2001 e 2007). Para a produ??o dos dados, realizamos an?lise documental (TRIVI?OS, 1987) do regimento e da proposta pedag?gica do Programa de P?s-Gradua??o de Sa?de Coletiva da UEFS. Tamb?m utilizamos entrevistas semiestruturadas (MINAYO, 2006), que foram realizadas com 12 estudantes desse Mestrado Acad?mico. Para a an?lise dos dados produzidos na investiga??o, utilizamos alguns princ?pios da An?lise de Conte?dos (BARDIN, 2011). No debate dos dados produzidos, identificamos cinco categorias, a saber: a primeira refere-se ao conceito de est?gio doc?ncia; na segunda, dialogamos sobre os saberes necess?rios para a doc?ncia universit?ria; a terceira, verificamos quais a/s contribui??o/?es do est?gio para a doc?ncia universit?ria; na quarta, descrevemos o processo da experi?ncia do Est?gio Doc?ncia e, finalmente, a quinta categoria, onde apresentamos as sugest?es para a melhoria da experi?ncia do Est?gio Doc?ncia, representadas por nossos colaboradores. As principais conclus?es desta pesquisa enfocam que o est?gio contribui para a prepara??o dos p?s-graduandos para a doc?ncia universit?ria, para o desenvolvimento da identidade docente, para aquisi??o de conhecimentos da realidade da sala de aula universit?ria, para a troca de saberes com o professor experiente e, por fim, para a percep??o dos mestrandos sobre a condi??o humana do profissional docente e a humaniza??o nas rela??es que ocorrem no contexto educativo. Al?m dessas contribui??es, os colaboradores da pesquisa enfocam a necessidade de o Programa de Sa?de Coletiva dar ? forma??o do professor o mesmo status que os estudos espec?ficos e a forma??o do pesquisador possuem no curr?culo, tendo em vista a complexidade da doc?ncia na atualidade.Os participantes ressaltam ainda a preval?ncia das seguintes dificuldades durante a experi?ncia do Est?gio Doc?ncia: aus?ncia de uma intera??o efetiva entre a Gradua??o e a P?s-Gradua??o, problemas estruturais e pol?ticos que prejudicaram o est?gio, dificuldades dos graduandos em compreenderem a import?ncia das disciplinas em suas forma??es, dificuldade did?tico-pedag?gica dos estagi?rios ao conduzir as disciplinas e embara?os dos mestrandos ao avaliar e lidar com os graduandos repetentes. Ademais, o estudo confirmou a necessidade da implanta??o de pol?ticas institucionais voltadas para a forma??o do professor universit?rio, especialmente os iniciantes, que est?o em per?odo de adapta??o e aprendizagem da profiss?o e, tamb?m, dos professores experientes, para que reflitam sobre suas pr?ticas de ensino continuamente, no intuito de inov?-las.

Use of satellite imagery makes environmental monitoring easy and convenient with little of the logistics involved in planning sampling campaigns. Colored dissolved organic matter (CDOM) is an important component to track as a proxy for the large pool of dissolved organic carbon (DOC). In a world contending with the looming issue of global climate change, the ability to investigate the carbon cycle of inland to coastal environments allows for examination of the magnitude of carbon flowing through the system and potential changes over years. The Arctic region is a critical area for climate change impacts but is a difficult landscape for sampling implementation and is thus an excellent target for satellite monitoring. This thesis focuses on the North Slopes region of Alaska to take advantage of the Toolik Lake monitoring site. Landsat 8 imagery has the appropriate spatial, spectral, and temporal resolutions for use in inland water and coastal environments. There are numerous developed algorithms for CDOM estimations, but many algorithms are designed for specific regions. A special challenge in inland environments is the bottom reflectance contribution to the outgoing light signal. An algorithm designed specifically for optically-shallow water environments (SBOP) was tested against two algorithms designed for optically-deep water environments (QAA-CDOM, K05). The relationship between CDOM and DOC was also investigated and used as further validation for algorithm performance. The SBOP algorithm shows promise iv alongside QAA-CDOM at estimating CDOM absorption, but the number of validation point makes pinpointing one algorithm difficult. All algorithms performed well at estimating DOC concentrations.

Im Fokus der Untersuchungen steht das hydrologische Einzugsgebiet der oberen Wilzsch im Westerzgebirge. Veränderte Stoffausträge des bewaldeten und zum Teil vermoorten hydrologischen Einzugsgebietes führen zu erhöhten Stoffkonzentrationen im Hauptzufluss der Trinkwassertalsperre Weiterswiese (Carlsfeld). Seitens der Trinkwasseraufbereitung stellen insbesondere die gestiegenen Gehalte an gelösten organischen Kohlenstoffen (DOC) Mehraufwendungen dar. Im Zuge der Wiedervernässung der Moorflächen kommt es zu relevanten bodenchemischen Veränderungen, die im Abfluss messbar sind. Eine räumliche Betrachtung der Teileinzugsgebiete des hydrologischen Einzugsgebietes der oberen Wilzsch ermöglicht, das Abflussgebiet in verschiedene Herkunftsräume zu gliedern. Dieser raumbezogene Ansatz leistet einen wesentlichen Beitrag in der Herkunftsanalytik von Wässern, deren Fließwege durch Standorte unterschiedlicher Nutzung geprägt sind. Die Arbeit bedient sich hydrochemischen Analysen sowie multitraceranalytischen Verfahren. Die Analyse der stabilen Umweltisotope ²H und 18O am Wasser, 13C am DIC und DOC, 34S und 18O am Sulfat sowie 15N und 18O am Nitrat hilft bei der Identifizierung von Stoffquellen und Transformationsprozessen. Die Arbeit verfolgt das Ziel, den Beitrag der verschiedenen Stoffsysteme am gesamten Stoffaustrag des Vorfluters aufzuzeigen sowie die atmosphärische Grundlast an den Messstandorten nachzuweisen. Dazu wurden von Mai 2009 bis August 2010 fünf Beprobungskampagnen angelegt. Das Messdesign erstreckte sich auf 19 Standorte in ausgewählten Teileinzugsgebieten, die maßgeblichen Einfluss auf die Vorflut haben. Parallel dazu erfolgte die Untersuchung des Niederschlags an der Station Talsperre Weiterswiese. Erfasst wurden die Inhalte von Wässern verschiedener Moorgebiete, Moorwasserpegel unterschiedlich degradierter Moorbereiche, Gräben und Bodendrainagen im Fichtenforst, der Vorfluter Wilzsch und Kranizsch und des Grundwassers im Fichtenforst. Es kann festgehalten werden, dass je nach Lage bzw. Entfernung der Ursprungsgebiete der Anteil des DOC - Exports unterschiedlich stark ist. So sind die DOC - Austräge saisonal sehr verschieden. Im Ergebnis ist der hydrochemische Beitrag - im Besonderen DOC - der unterschiedlichen Stoffsysteme des hydrologischen Einzugsgebietes letztlich am finalen Pegel der Wilzsch messbar. Die vom Basisabfluss gesteuerten silikatischen Standorte im Fichtenforst leisten einen wesentlichen Anteil zum hydrochemischen Milieu der Vorfluter. Die im Untersuchungsgebiet eingeleiteten Renaturierungsmaßnahmen beeinflussen die Trinkwasserqualität in der Talsperre Carlsfeld nicht. Eine Abgrenzung der atmosphärischen Grundlast ist ebenfalls möglich, atmogen eingetragene Stoffe können an den Standorten ausgewiesen werden.

No description available.

[ES] Esta tesis doctoral abarca el desarrollo de algoritmos orientados a mejorar el sistema de control de emisiones en motores Diesel. Para este propósito, la inclusión en el vehículo de sensores embarcados como los de temperatura, los de NOx o el de NH3 permite realizar diagnóstico a bordo de los sistemas de post-tratamiento foco de este trabajo, los cuales son el DOC y el SCR. Así pues, el objetivo es el de satisfacer las normativas de diagnóstico a bordo para mantener las emisiones por debajo del umbral permitido por la normativa a lo largo del tiempo. Los tests experimentales, incluyendo las medidas con analizador de gases, permiten tener una visión más amplia de las especies en la línea de escape. Complementariamente, se utilizan unidades nuevas y envejecidas para tener el efecto experimental del envejecimiento en los catalizadores. De esta manera, se analiza el efecto de la temperatura, el gasto de escape, las concentraciones de las especies y el envejecimiento en el DOC y en el SCR, así como la evaluación de algunas de las medidas relevantes realizadas por los sensores. Las temperaturas tienen una influencia destacada en el funcionamiento de los catalizadores, por lo que se requiere la evaluación de las medidas de los sensores de temperatura, junto con el desarrollo de modelos de transmisión de calor, para alimentar las funciones a continuación desarrolladas. En este sentido, la medida lenta del sensor aguas arriba del DOC se mejora en condiciones transitorias mediante una técnica de fusión de la información basada en un filtro de Kalman. Luego, se presenta un modelo de transmisión de calor 1D y un modelo agrupado 0D, en los cuales se evalúan las entradas aguas arriba según el uso del modelo. Por otra parte, se presenta una técnica para estimar el incremento de temperatura debido a la oxidación de los pulsos de post-inyección en el DOC. Se proponen modelos para ambos DOC y SCR para estimar el efecto del envejecimiento en las emisiones, en los cuales el factor de envejecimiento es modelado como un parámetro sintonizable que permite variar desde estados nuevos a envejecidos. Por una parte, un modelo agrupado 0D es desarrollado para el DOC con el propósito de estimar el desliz de HC y CO, el cual es validado en un WLTC para después ser usado en simulación. Por otra parte, un modelo 1D y un modelo 0D se desarrollan para el SCR, los cuales se usan a continuación para alimentar la estrategia de diagnóstico y para simulación. Finalmente, las estrategias de diagnóstico se presentan para fallo total o retirada de DOC, así como para la estimación de la eficiencia en DOC y SCR. Por una parte, la primera estrategia se divide en pasiva y activa, en la que se usan post-inyecciones en la activa para excitar el sistema y confirmar el fallo total si es el caso. A continuación, la eficiencia del DOC se estima a través de una técnica indirecta en la que la temperatura de activación se detecta y se relaciona con el incremento de emisiones a través del modelo. Por otra parte, se desarrolla un observador para estimar el estado de envejecimiento del SCR, el cual está basado en un filtro de Kalman extendido. Sin embargo, para evitar asociar baja eficiencia del catalizador debido a pobre calidad de la urea inyectada, a envejecimiento del SCR, un indicador de la calidad de la urea se ejecuta en paralelo. / [CA] Esta tesi doctoral abasta el desenvolupament d'algoritmes orientats a millor el sistema de control d'emissions en motors Diesel. Per a este propòsit, la inclusió en el vehicle de sensor embarcats com els de temperatura, els de NOx o el d'NH3 permet realitzar el diagnòstic a bord dels sistemes de post-tractament focus d'este treball, els quals són el DOC i el SCR. Així doncs, l'objectiu és el de satisfer les normatives de diagnòstic a bord per a mantindre les emissions per baix de l'umbral permés per la normativa al llarg del temps. Els tests experimentals, incloent les mesures amb analitzador de gasos, permeten obtindre una visió més àmplia de les espècies en la línia d'escapament. Complementàriament, s'utilitzen unitats noves i envellides per tal de tindre l'efecte experimental de l'envelliment en els catalitzadors. D'aquesta manera, s'analitza l'efecte de la temperatura, la despesa d'escapament, les concentracions de les espècies i l'envelliment en el DOC i en el SCR, així com l'avaluació d'algunes mesures rellevants realitzades pels sensors. Les temperatures tenen una influència destacada en el funcionament dels catalitzadors, pel que es requerix l'avaluació de les mesures dels sensors de temperatura, junt amb el desenvolupament de models de transmissió de calor, per a alimentar les funcions a continuació desenvolupades. En este sentit, la mesura lenta del sensor a l'entrada del DOC es millora en condicions transitòries mitjançant una tècnica de fusió de la informació basada en un filtre de Kalman. Després, es presenta un model de transmissió de calor 1D i un model agrupat 0D, en els quals s'avaluen les entrades a l'entrada segons l'ús del model. Per altra banda, es presenta una tècnica per a estimar l'increment de temperatura degut a l'oxidació dels polsos de post-injecció en el DOC. Es proposen models per a DOC i SCR per a estimar l'efecte de l'envelliment en les emissions, en els quals es modela el factor d'envelliment com un paràmetre sintonitzable, que permet variar des d'estats nous a envellits. Per altra banda, un model agrupat 0D _es desenvolupat per al DOC amb el propòsit d'estimar la relliscada de HC i CO, el qual és validat en un WLTC per a després ser usat en simulació. Per altra banda, un model 1D i un model 0D es desenvolupen per al SCR, els quals s'usen a continuació per a alimentar l'estratègia de diagnòstic i per a simulació. Finalment, les estratègies de diagnòstic es presenten per a la fallada total o retirada del DOC, així com per a l'estimació de l'eficiència en DOC i SCR. Per altra banda, la primera estratègia es divideix en passiva i activa, en la que s'utilitzen post-injeccions en la activa per a excitar el sistema i confirmar la fallada total si es dona el cas. A continuació, l'eficiència del DOC s'estima a través d'una tècnica indirecta en la que la temperatura d'activació es detecta i es relaciona amb l'increment d'emissions a través del model. Per altra banda, es desenvolupa un observador per a estimar l'estat d'envelliment del SCR, el qual està basat en un filtre de Kalman extés. No obstant això, per a evitar associar baixa eficiència degut a pobre qualitat de l'urea injectada a l'envelliment del SCR, un indicador de la qualitat de l'urea s'executa en paral·lel. / [EN] This dissertation covers the development of algorithms oriented to improve the emission control system of Diesel engines. For this purpose, the inclusion of on-board sensors like temperature, NOx and NH3 sensors allows performing on-board diagnostics to the after-treatment systems focus of this work, which are the DOC and the SCR system. Then, the target is to meet on-board diagnostics regulations in order to keep emissions below a regulation threshold over time. Experimental tests, including gas analyzer measurements, allow having a wider view of the species in the exhaust line. Complementary, new and aged units are used in order to have the experimental effect of ageing on the catalysts. Then, the effect of temperature, exhaust mass flow, species concentrations and ageing is analyzed for DOC and SCR, in combination with the assessment of some relevant sensors measurements. As a result, the characteristics, opportunities and limitations extracted from experimental data are used as the basis for the development of models and diagnostics techniques. The assessment of temperature sensors measurements, along with the development of heat transfer models is required to feed temperature dependent functions. In this sense, the slow measurement of the DOC upstream temperature sensor is improved in transient conditions by means of a data fusion technique, based on a fast model and a Kalman filter. Then, a 1D and a 0D lumped heat transfer models are presented, in which the upstream inputs are assessed in relation to its use. On the other hand, a technique to estimate the temperature increase due to post-injection pulses oxidation is also presented. Both DOC and SCR models are proposed in order to estimate the effect of ageing on emissions, in which an ageing factor is modelled as a tunable parameter that allows varying from new to aged states. On the one hand, a 0D lumped model is developed for DOC in order to estimate the HC and CO species slip, which is validated in a WLTC and is then used for simulation. On the other hand, a 1D and a 0D models are developed for SCR, which are then used to feed the diagnostics strategy and for simulation. Finally, diagnostics strategies are presented for total failure or removal of DOC, as well as for efficiency estimation of DOC and SCR. On the one hand, the former strategy is separated into passive and active diagnostics, in which post-injections are used in active diagnostics in order to excite the system and confirm a total failure, in case. Then, the DOC efficiency estimation is done by means of an indirect technique in which the light-off temperature is detected and an emissions increase is related by means of the DOC ageing model. On the other hand, an observer to estimate the SCR ageing state is developed, which is based on an extended Kalman filter. However, in order to avoid associating low SCR efficiency to ageing, an indicator of the injected urea quality is developed to run in parallel. / Mora Pérez, J. (2018). Control-oriented modelling and diagnostics of diesel after-treatment catalysts [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/115937

Ces travaux de thèse ont pour vocation d'étudier des oxydes mixtes Ce1-x-yZrxPryO2-z afin de corréler composition chimique-structure avec les propriétés de réductibilité/mobilité ionique de l'oxygène associées aux performances catalytiques pour l'oxydation du CO et du propane, en conditions essence et Diesel. La connaissance de la quantité de terres rares au degré d'oxydation +4 a été déterminante. Notamment, plus le taux de Pr4+ est important, plus le composé est réductible et plus la mobilité de l'oxygène s'accroît. L'évaluation du coefficient de diffusion de l'oxygène D* a montré que sa valeur devenait élevée, rivalisant ainsi avec les meilleurs conducteurs ioniques de l'oxygène à basse température. Les échanges isotopiques de l'oxygène permettent de montrer que la vitesse d'échange croît quand le taux de Pr augmente. L'étude de la combustion du propane sur ces oxydes a montré qu'une bonne mobilité de l'oxygène permettait d'améliorer les performances catalytiques. Ainsi, l'oxyde de composition Ce0,45Zr0,1Pr0,45O2-x (CZP45) présente les meilleures propriétés pré-citées et l'activité catalytique la plus élevée. L'oxyde CZP45 a donc été imprégné de Pd afin d'être comparé à deux catalyseurs utilisés industriellement et à iso-teneur en Pd, dispersée sur ?-Al2O3 (Diesel) et Ce0,5Zr0,5O2-x (essence). En régime Diesel, Pd-CZP45, après une étape initiale de réduction, présente une meilleure activité catalytique à basse température que Pd-?-Al2O3 pour l'oxydation du propane. Nous avons expliqué ces excellentes performances par la présence de clusters de Pd2+/Pd° finement dispersés sur l'oxyde (CZP45) et par la capacité du catalyseur à adsorber et conduire l'oxygène / This work describes characterizations of Ce1-x-yZrxPryO2-z mixed oxides to link their chemical composition-structure with their reducibility/oxygen mobility. These latter properties were correlated with their catalytic activity for the oxidation of CO and propane, both in stoichiometric (gasoline) and lean-burn (Diesel) conditions. The determination of the quantity of rare earth at the +4 oxidation degree, especially for Pr4+, has been of paramount importance. Actually, the higher the Pr4+ rate, the more reducible is the oxide and the better is the oxygen mobility. The evaluation of the diffusion coefficient of the oxygen D* highlighted high values, similar to those of the best reported oxygen ionic conductors at low temperature. Isotopic exchanges showed that the oxygen exchange rate increases with the Pr loading in the oxide. The catalytic activity for propane combustion of these oxides increases with their oxygen mobility. Finally, CZP45 (Ce0,45Zr0,1Pr0,45O2-x) exhibits the best pre-quoted properties as well as the highest catalytic activity. Therefore, CZP45 has been impregnated with Pd. The activity of Pd-CZP45 catalyst was compared with two industrially catalysts containing the same Pd content supported either on ?-Al2O3 (Diesel) or Ce0,5Zr0,5O2-x (gasoline). In Diesel conditions, Pd-CZP45 shows a better low-temperature catalytic activity than Pd-?-Al2O3 for propane oxidation after an initial step of reduction. We have attributed these remarkable performances to the presence of Pd2+/Pd° clusters finely dispersed on the oxide CZP45 and to its ability to adsorb and conduct oxygen

This study investigated characteristics of algal organic matter (AOM) derived from four species (cyanobacteria Microcystis aeruginosa and Merismopedia tenuissima, diatom Fragilaria crotonensis and green alga Chlamydomonas geitleri) dominating phytoplanktonic populations in the reservoirs supplying drinking water treatment plants - the water reservoirs Švihov (the Želivka water treatment plant) and Josefův Důl (the Jizerské Mountains), Czech Republic. The four mentioned microorganisms were cultivated under laboratory conditions and the algal growth was quantified by a number of cells, chrorophyll-a and optical density. Production of AOM was evaluated by dissolved organic carbon concentration measurements, by specific UV absorbance, the amount of peptide/protein and non-peptide (carbohydrate) contents, water affinity and molecular weight (MW). AOM of all considered microorganisms are formed predominantly by hydrophilic substances with low values of specific UV absorbance (< 2 L/(m.mg)). Considerable portions of both types of AOM, i.e. extracellular and cellular organic matters are represented by substances with MW < 1 kDa or with MW > 100 kDa. However, the total amount and composition of AOM significantly depend on algal species and their growth. The obtained results imply that the knowledge of AOM...