In-situ upgrading of oil using hydrogen donors is a new process. In particular, very little research has been conducted with respect to in-situ oil upgrading using hydrogen donor under in-situ combustion. Several papers describe the use of metal additives mixed with oil and their influence on oil properties such as viscosity and API gravity. The main objective of my research is to determine if a catalyst mixed with a hydrogen donor (tetralin) is going to affect the Jobo crude oil properties while undergoing in-situ combustion. Six runs were performed with Jobo crude oil (9-11ºAPI) from the Orinoco Belt in Venezuela. Four of the runs were successful. Two of them are base runs; the remaining ones are with tetralin with concentration of 5 wt% (of oil) and catalyst with concentration of 750 ppm. For all runs, the following were kept constant: the air injection rate (3 std. L/min) and production (combustion tube outlet) pressure, 300 psig. Concentration by weight of oil, water, and sand in the samples were approximately 4.8%, 4.2%, and 91% respectively. Oil viscosity at the end of combustion at 40oC decreased from 42.3 and 73.6 to 16.6 and 25.2; API gravity at the end of combustion increased from 18.4 and 16.8 to 20 and 18.8. Oil recovery is higher; combustion front velocity is faster in the case of additives, water production decreased. Since oil viscosity decreased and API gravity increased oil moves faster and consequently combustion time is lower.

In-situ upgrading of oil using hydrogen donors is a new process. In particular, very little research has been conducted with respect to in-situ oil upgrading using hydrogen donor under in-situ combustion. Several papers describe the use of metal additives mixed with oil and their influence on oil properties such as viscosity and API gravity. The main objective of my research is to determine if a catalyst mixed with a hydrogen donor (tetralin) is going to affect the Jobo crude oil properties while undergoing in-situ combustion. Six runs were performed with Jobo crude oil (9-11ºAPI) from the Orinoco Belt in Venezuela. Four of the runs were successful. Two of them are base runs; the remaining ones are with tetralin with concentration of 5 wt% (of oil) and catalyst with concentration of 750 ppm. For all runs, the following were kept constant: the air injection rate (3 std. L/min) and production (combustion tube outlet) pressure, 300 psig. Concentration by weight of oil, water, and sand in the samples were approximately 4.8%, 4.2%, and 91% respectively. Oil viscosity at the end of combustion at 40°C decreased from 42.3 and 73.6 to 16.6 and 25.2; API gravity at the end of combustion increased from 18.4 and 16.8 to 20 and 18.8. Oil recovery is higher; combustion front velocity is faster in the case of additives, water production decreased. Since oil viscosity decreased and API gravity increased oil moves faster and consequently combustion time is lower.

Transition metal oxynitrides are of growing interest for their use as electrocatalyst for nitrogen reduction reaction. The metals in the oxynitride used for catalytic process are stabilized in intermediate state for effective activation of nitrogen. Therefore, studying the interaction of metal oxynitrides films to ambient exposure is necessary. Here, sputter deposited vanadium oxynitride is compared to cobalt oxynitride using insitu Auger electron spectroscopy (AES), ex situ X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). After deposition in Ar/N2 environment, in situ AES spectra indicate that film is vanadium oxynitride despite oxygen is not the reactive gas. In contrast, in situ AES indicate film is pure cobalt nitride at the same base pressure and deposition condition (as vanadium). For ambient exposure, in situ AES indicate the incorporation of oxygen in the cobalt nitride film to form cobalt oxynitride. Ex situ XPS indicate both films get more oxidized but uniformly distributed as there is only slight difference in grazing and normal emission XPS. XRD and SEM also indicate how homogeneously distributed both films are. These finding confirms how important it is that transition metal centers are kept in intermediate oxidation state for the activation of nitrogen bond.

Over the last decade progress towards step-wise structural transformations in solid state chemistry has been made using metal hydride reductants. Alkali and alkali-earth metal hydrides can effectively reduce transition metal oxides resulting frequently in novel oxygen defect structures. This provides access to control over cation oxidation states and magnetic exchange pathways, and thus electronic and magnetic properties. The goal for this research was to investigate a representative system that could be used both for exploration of novel oxygen defect phases and for investigating the fundamental parameters governing successful solid state reductions. The systems chosen for investigation were Sr2-xCaxMnO4 (0<x<2) and Sr2-xBaxMnO4 (x< 0.04). Detailed analysis of metal hydride reactivity with Sr2MnO4 is presented in addition to proof of the solid state reduction mechanism. As a result a number of novel oxygen defect phases have been produced, Sr2MnO4-x (0<x<0.37). The potential for producing novel lithium doped Sr2MnO4-x phases using a reduction/insertion approach with LiH has also been identified. Lastly as a test of application for metal hydrides as reductants the ability to topotactically reduce ScVO4 has been investigated.

Over the last decade progress towards step-wise structural transformations in solid state chemistry has been made using metal hydride reductants. Alkali and alkali-earth metal hydrides can effectively reduce transition metal oxides resulting frequently in novel oxygen defect structures. This provides access to control over cation oxidation states and magnetic exchange pathways, and thus electronic and magnetic properties. The goal for this research was to investigate a representative system that could be used both for exploration of novel oxygen defect phases and for investigating the fundamental parameters governing successful solid state reductions. The systems chosen for investigation were Sr2-xCaxMnO4 (0<x<2) and Sr2-xBaxMnO4 (x< 0.04). Detailed analysis of metal hydride reactivity with Sr2MnO4 is presented in addition to proof of the solid state reduction mechanism. As a result a number of novel oxygen defect phases have been produced, Sr2MnO4-x (0<x<0.37). The potential for producing novel lithium doped Sr2MnO4-x phases using a reduction/insertion approach with LiH has also been identified. Lastly as a test of application for metal hydrides as reductants the ability to topotactically reduce ScVO4 has been investigated.

In the field of tyre technology, silica filled tyres are generally considered as a lower energy consumption product due to their lower rolling resistance characteristics. Additionally, they can offer excellent grip on the wet and snowy conditions which are more essential from the safety perspective. However, the proper dispersion of the silica in rubber compounds is one of the challenging tasks to engineers, physicist and chemist. In this thesis, a very controlled in-situ silica based solution styrene butadiene rubber composites were developed and intensively investigated by the synthesis of sol-gel silica in presence of polymer solution. It means the silica particles were allowed to grow in the presence of rubber in the reaction mixture. It was observed that the sizes of the synthesized silica particles are rather larger than standard precipitated commercial silica particles. In depth morphological investigation revealed that the obtained sol-gel silica particles appear in strong cluster form with primary particle size of 10 - 15 nm and final aggregated size of 200 to 400 nm. Nevertheless, the final mechanical performance and other rubber related properties of in-situ derived silica composites are better in many important aspects for technical applications as compared with commercial silica at a given loading of fillers. Owing to the presence of more active hydroxyl group on the surface of sol-gel silica, the effective coupling between silica and rubber has been established. Furthermore, the permanent trapped rubber chains inside the large aggregates of sol-gel silica particles enable the compounds to offer good mechanical reinforcement, higher resilience, and dynamic mechanical properties. The present work is a humble approach to pave an alternative novel way for silica-rubber composite preparation in order to minimize the problem of silica mixing with the rubbers. / Auf dem Gebiet der Reifentechnologie zeichnen sich Kieselsäure-(Silika)-gefüllte Reifen aufgrund ihres charakteristisch geringeren Rollwiderstands allgemein als ein Produkt mit geringerem Energieverbrauch aus. Darüber hinaus bieten sie ein hervorragendes Nasshaftvermögen, welches eine essentielle physikalische Kenngröße für die Fahrsicherheit darstellt. Allerdings stellt eine optimale Dispergierung der Silikafüllstoffs in Kautschukmischungen eine anspruchsvolle Aufgabe für Ingenieure, Physiker und Chemiker dar. Im Rahmen der vorliegenden Arbeit wurden Silika / Styrol-Butadien-Kautschuk-Verbundwerkstoffe mittels eines in-situ Sol-Gel-lösungsmittelbasierten Reaktionsverfahrens entwickelt. Diese Technologie beruht auf der Nukleierung von Kieselsäure-Partikeln in Gegenwart des Elastomers in einer Syntheselösung. Dabei wurde beobachtet, dass die Partikel der so synthetisierten Silika-Teilchen größer sind, als die eines kommerziellen Standard-Silika-Füllstoffs. Eine umfassende morphologische Untersuchung zeigt, dass die in-situ synthetisierten Silikapartikel sphärisch sind und eine Primärteilchengröße von 10 bis 15 nm aufweisen. Diese nanoskaligen Teilchen agglomerieren sich zu größeren sphärischen Clustern mit einer Größe von 200 bis 400 nm und weisen somit eine andere Morphologie auf, als die kommerziell erhältlichen Silika-Füllstoffe. Die statisch- und dynamisch-mechanischen Eigenschaften, sowie weitere elastomerbezogene Eigenschaften der in-situ synthetisierten Silika/Styrol-Butadien-Kautschuk-Verbundwerkstoffe, wie z.B. Rückprallelastizität, mechanisch induzierte Wärmeentwicklung und Spannung-Dehnungshysterese, zeigen verbesserte Werte im Vergleich zu Elastomermaterialien gefüllt mit kommerzieller Kieselsäure. Eine erhöhte Anzahl von Hydroxylgruppen auf der Oberfläche der in-situ synthetisierten Silikapartikel, verbunden mit permanenter Adsorption der Polymerketten des Elastomers auf der Teilchenoberfläche ermöglicht die Ausbildung eines Elastomerverbundes mit verbesserter mechanischer Verstärkung mit oder ohne Einsatz eines haftvermittelnden Silans, wie z.B. TESPT (Bis [3-(triethoxysilyl)propyl]-tetrasulfid). Die Wechselwirkungen zwischen Elastomer und Füllstoff, zwischen den Füllstoffpartikeln, sowie der Verstärkungsmechanismus des in-situ synthetisierten Füllstoffes wurden mittels dynamischmechanischer Analyse (Amplitudentests), Festkörper-NMR und energiedispersiver Röntgenspektroskopie umfassend analysiert. Der vorliegende Ansatz verdeutlicht, dass die in-situ Generierung des Füllstoffes im Elastomer ein vielversprechendes und alternatives Verfahren zur Herstellung von Elastomermaterialien mit verbesserter Silika-Dispergierung, sowie erhöhter Elastomer-Füllstoff-Wechselwirkung bietet.

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This Master thesis is written in the field of collaborative planning aiming to challenge the collaborative approach on it applicability, especially in the context of the Global South. As a case study it looks on the urban poor community participatory practice, the so called 're-blocking' in Cape Town – an example of insitu informal settlement upgrading. It questions not only to what extent re-blocking displays a successful approach of collaborative planing but also whether it can lead to more inclusive cities in South Africa. The field data was gained through qualitative semi-structured interviews, observations and an analysis of national housing policy documents. The findings evaluate re-blocking as a successful example of collaborative planning in the sense that local communities are truly involved in the process and have a lot of decision making power. Also, re- blocking can be replicable to other cities in South Africa. Yet it faces several risks in community mobilisation and communication and can only be operated on a small scale. Therefore, the thesis concludes that re-blocking itself may not lead to inclusive cities, however as an example of community participation it may change the mindset of the South African society and (local) government towards informal community inclusion.

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