Frustrierte Lewis-Paare (FLPs) bestehen aus einer Lewis-Säure und -Base, die an der gegenseitigen Neutralisierung gehindert werden und so erfolgreich zur Aktivierung kleiner Moleküle eingesetzt werden konnten. Als Elektronenpaarakzeptoren wurden bislang vorwiegend Borane erforscht. Aluminiumbasierte Systeme, insbesondere intramolekularer Art, sind trotz ihrer ausgeprägten Lewis-Acidität unterrepräsentiert. In der vorliegenden Dissertation wurde untersucht, welche Syntheserouten sich zur Darstellung intramolekularer Phosphor/Aluminium-FLPs mit großer räumlicher Trennung der Lewis-Funktionen eignen und welche Reaktivität diese aufweisen. An einem Xanthenrückgrat mit Diphenylphosphineinheit konnten durch Lithiierung und Metathese Dimesityl- und Bis(pentafluorphenyl)alaneinheiten eingeführt werden und die resultierenden P/Al-FLPs sind in der Lage, Tetrahydrofuran zu öffnen. Das perfluorierte Derivat wies dabei eine zehnfach höhere Geschwindigkeitskonstante der Ringöffnungsreaktion auf. Mittels quantenchemischer Rechnungen konnte dies auf die gesteigerte Lewis-Acidität des Aluminiumzentrums zurückgeführt werden. Durch den Zinn-Aluminium-Austausch eines trimethylstannylierten Xanthenvorläufers mit Methylaluminiumverbindungen konnten P/Al-FLPs aufgebaut werden, die durch ein weiteres Äquivalent des Alanpräkursors stabilisiert werden. Die Verbindungen sind imstande, Kohlenstoffdioxid zu aktivieren, wobei die CO2-Addukte der verschiedenen Derivate mit zunehmender Anzahl elektronegativer Substituenten an den Aluminiumzentren eine zunehmende thermodynamische Stabilisierung erfahren. Die neuartige Syntheseroute konnte auch zur Darstellung eines biphenylengebundenen P/Al-FLPs genutzt werden. In diesem Fall ist das Aluminiumzentrum durch die Wechselwirkung mit dem Phosphandonor ausreichend gesättigt, um die Isolierung der gespannten Verbindungen in monomerer Form zu ermöglichen. Dennoch weist das Alan eine hohe Lewis-Acidität auf und der FLP reagiert mit CO2 und Propadien. / Frustrated Lewis pairs (FLPs) consist of a Lewis acid and base, which are prevented from neutralising each other and in turn could be successfully used to activate small molecules. Boranes have been predominantly explored as electron pair acceptors. In contrast, aluminium-based systems, in particular intramolecular ones, are underrepresented despite their pronounced Lewis acidity. The aim of the present dissertation was to fathom which synthetic route is suitable for the preparation of intramolecular phosphorus/aluminium FLPs with large spatial separation of the Lewis functions and to investigate their reactivity. On a xanthene backbone bearing a diphenylphosphine moiety, dimesityl and bis(pentafluorophenyl)alane units could be introduced by lithiation and metathesis, and the resulting P/Al-FLPs are able to open tetrahydrofuran. The perfluorinated derivative exhibited a tenfold higher rate constant of the ring opening reaction. Using quantum chemical calculations, this could be attributed to the increased Lewis acidity of the aluminium centre. Using a tin-aluminum exchange on a trimethylstannylated xanthene precursor with methylaluminium compounds, P/Al-FLPs could be constructed, which are stabilised by another equivalent of the aluminium precursor. The compounds are capable of activating carbon dioxide, and the CO2 adducts of the various derivatives become increasingly stabilised as the number of electronegative substituents at the aluminium centres increases. The novel synthetic route could also be applied for the synthesis of a P/Al-FLP on the biphenylene linker. In this case, the aluminium centre is sufficiently saturated by an interaction with the phosphane donor to permit the isolation of the strained compounds in monomeric form. Nevertheless, the alane exhibits high Lewis acidity and the FLP reacts with CO2 and propadiene.

Das „Strongly Constrained and Appropriately Normed“ (SCAN) Austausch-Korrelations-Funktional gehört zur Familie der meta-GGA (generalized gradient approximation) Funktionale. Es gibt aber auch Nachteile Zum einen leiden SCAN Rechnungen oft unter numerischen Instabilitäten, wodurch sehr viele Iteration zum Erreichen von Selbst-Konsistenz benötigt werden. Zum anderen leidet SCAN unter dem von GGA Methoden bekannten Selbstwechselwirkung-Fehler. Im ersten Teil der Arbeit habe ich die numerischen Stabilitätsprobleme in SCAN Rechnungen im Rahmen der numerischen Realraum-Integrationsroutinen im Code FHI-aims untersucht. Diese Analyse zeigt, dass die genannte Probleme durch Anwendung von standardisierten Dichte-Mischalgorithmen für die kinetische Energiedichte abgemildert werden können. Dadurch wird auch in SCAN-Rechnungen eine schnelle und stabile Konvergenz zur selbstkonsistenten Lösung ermöglicht. Im zweiten Teil der Arbeit habe ich untersucht, in welchem Rahmen sich der Selbstwechselwirkung-Fehler in SCAN mittels des von Perdew und Zunger vorgeschlagenen Selbstinteraktionskorrekturalgorithmus (PZ-SIC) verringern lässt. Es wurden aber auch Optimierungen für die PZ-SIC Methode entwickelt. Inspiriert von den ursprünglichen Argumenten in der PZ-SIC-Methode und anderen lokalisierten Methoden, wird in dieser Arbeit eine neuartige Randbedingung (orbital density constraint) vorgeschlagen, die sicherstellt, dass die PZ-SIC Orbitale während des Selbstkonsistenzzyklus lokalisiert bleiben. Dies mildert die Anfangswertabhängigkeit deutlich ab und hilft dabei, in die korrekte selbst-konsistente Lösung mit minimaler Energie zu konvergieren, unabhängig davon ob reelle oder komplexe SIC Orbitale verwendet werden. Die in dieser Arbeit getägtigen Entwicklungen und Untersuchungen sind Wegbereiter dafür, in Zukunft mit SIC-SCAN Rechnungen deutlich genauere ab initio Rechnungen mit nur gering höherem Rechenaufwand durchführen zu können. / The state-of-the-art “Strongly Constrained and Appropriately Normed” (SCAN) functional pertains to the family of meta-generalized-gradient approximation (meta-GGA) exchange-correlation functionals. Nonetheless, SCAN suffers from some well-documented deficiencies. In the first part of this thesis, I revisited the known numerical instability problems of the SCAN functional in the context of the numerical, real-space integration framework used in the FHI-aims code. This analysis revealed that applying standard density-mixing algorithms to the kinetic energy density attenuates and largely cures these numerical issues. By this means, SCAN calculations converge towards the self-consistent solution as fast and as efficiently as lower-order GGA calculations. In the second part of the thesis, I investigated strategies to alleviate the self-interaction error in SCAN calculations by using the self-interaction correction algorithm proposed by Perdew and Zunger (PZ-SIC). Inspired by the original arguments in PZ-SIC and other localized methods, I introduced a mathematical constraint, i.e., the orbital density constraint, that forces the orbitals to retain their localization throughout the self-consistency cycle. In turn, this alleviates the multiple-solutions problem and facilitates the convergence towards the correct, lowest-energy solution both for complex and real SIC orbitals. The developments and investigations performed in this thesis pave the road towards a more wide-spread use of SIC-SCAN calculations in the future, allowing more accurate predictions within only moderate increases of computational cost.

Dies ist ein kurzer Überblick über Python-Projekte abseits von Einsatzmöglichkeiten im Beruf.:1. Einleitung 2. Python unterrichten 3. Mit Python promovieren 4. Mit Python chatten lassen 4.1. Implementation 4.2. Literaturwissenschaftlicher Hintergrund 5. Mit Python leben 6. Mit Python basteln Literatur

In dieser Dissertation werden die Repräsentationen von Kulturtransfer in zeitgenössischen britischen Romanen untersucht (Monica Ali: Brick Lane (2003), Nadeem Aslam: Maps For Lost Lovers (2004), Gautam Malkani: Londonstani (2007) und Maggie Gee: The White Family (2002)). Für die Analyse der Begegnungen und Kulturtransferprozesse werden narratologische Analysekategorien mit denen der Kulturtransferanalyse verknüpft. Neben den textimmanenten Aspekten werden außerdem die Produktions- und Rezeptionskontexte der Romane mitberücksichtigt. Dazu gehören u.a. auch das Buchmarketing und Buchumschlagdesign sowie Rezensionen und öffentliche Reaktionen auf die Romane. Mit diesem Instrumentarium werden z.B. folgende Fragen untersucht: Wie werden Begegnungen und Austauschprozesse repräsentiert und bewertet? Welche Gründe für Aneignung oder Abschottung werden formuliert? In diesem Kontext konzentriert sich die Arbeit auf die Repräsentation von Mediatorinnen und Mediatoren, Kontaktzonen und -situationen, Machtstrukturen sowie Selektions- und Ablehnungsprozesse. Außerdem wird untersucht, mit welchen ästhetischen Mitteln die Austauschprozesse gestaltet werden, beispielsweise durch die Untersuchung der Plotmuster und der Charakterisierungen auf Stereotype hin. und welche Effekte dies bewirkt. Die Analysen haben ergeben, dass Kulturtransfer als erstrebenswert bewertet wird. Gleichzeitig findet aber oft nur Assimilierung statt und kein reziproker Austausch auf Augenhöhe. Die ausgewählten Romane setzen sich vorwiegend mit Hindernissen des interkulturellen Austauschs auseinander. Besonders häufig werden in diesem Kontext Gründe wie mangelnde Bereitschaft, mangelnde Bildung und extremistische (religiöse) Ansichten der Einwandererfamilien angeführt. Die Romane verstetigen Stereotype, die dem Lesepublikum bereits aus vielen Massenmedien vertraut sind, u.a. durch entwicklungsresistente Charaktere, typisiert als ungebildete und unverbesserliche Migranten, die Parallelgesellschaften entwerfen. / This thesis analyses representations of cultural exchange in contemporary British novels in the context of migration and the British literary field. It offers a multilayered approach: the combination of cultural exchange theory and its categories with narratological tools do justice to the aesthetic side of the novels as well as their socio-political and historical contexts that are particularly relevant for novels dealing with migration. Cultural exchange theory analyses appropriation and transformation processes, i.e. how the concepts, cultural practices as well as representations change when they are transferred into a different cultural context. Furthermore, this thesis takes into consideration that all novels exist as material objects within a literary field that is affected by editors, marketing people, reviewers, and other agents. The results support the following theses: Contact and exchange are implicitly and explicitly depicted as something positive, with two of the novels emphasising the virtues of selective appropriation. However, the exchange processes mainly work in one direction only and contact between (British) Asian and (white) British characters is limited. The blame for this is often put on the immigrants and their families. The selected texts focus on obstacles and conflicts in exchange processes without offering solutions to the conflicts. In this context, religion or religious fervour along with a lack of education are most often depicted as the main obstacle for reciprocal cultural exchange. The aesthetic means employed are analysed as well as their effects, e.g. whether form and content reinforce each other or produce contradictions. Finally, the thesis shows which novels deconstruct and contradict existing stereotypes and which ones are complicit in reproducing them. Primary texts: Monica Ali’s Brick Lane (2003), Nadeem Aslam’s Maps for Lost Lovers (2004), Gautam Malkani’s Londonstani (2006) and Maggie Gee’s The White Family (2002).

In this work, low dimensional iron group clusters have been studied by application of high magnetic fields. The magnetization has been probed with an MPMS as function of temperature and field. The combination with pulse field measurements up to 52\,T allowed determination of the magnetic exchange coupling parameters, and to probing the effective spin of the ground state. The main focus was on tunable high-field/high-frequency (tHF) ESR in static fields < 17 T and pulse field ESR up to 36 T. This magnetic resonance method has been used for the characterization of the local magnetic properties: The detailed analysis of the field dependence of dedicated spin states allowed to determine the magnetic anisotropy and g-factors. The results were analyzed in the framework of the appropriate effective spin Hamiltonians in terms of magnetization fits and ESR spectrum simulations.

Betreute kulturelle Exkursionen sind ein fester Bestandteil von vielen Study-Abroad-Programme. Sie werden allgemein positiv bewertet und bieten viele Chancen für fremdsprachliches und landeskundliches Lernen, sowie als „Handlungsfeld“ für das Gelernte. Es fehlen jedoch wissenschaftliche Begründungen sowie empirische Untersuchungen, die den Lernwert von Exkursionen bei Study-Abroad-Programmen nachweisen. Deshalb wurden folgenden Leitfragen untersucht: Welche Lerneffekte können Exkursionen bei Study-Abroad-Programmen haben? Welche Lerneffekte haben Exkursionen tatsächlich bei Study-Abroad-Programmen? Ziel dieser Masterarbeit ist es, die Lerneffekte von Exkursionen im Rahmen eines Study-Abroad-Programms theoretisch und empirisch zu untersuchen. / Supervised cultural excursions are often included in the offerings of foreign language immersion study abroad programs. Such excursions have the potential to achieve a depth beyond sightseeing. Under certain conditions, excursions can foster linguistic and intercultural learning and skill acquisition in a setting that has advantages not only over the traditional classroom, but also over daily unsupervised immersion. These conclusions can be intuitively inferred, but have never been supported by empirical evidence. Therefore, the questions which guided this outcomes assessment research were: What are the potential learning effects of immersion program excursions? What are the actual learning effects of immersion program excursions? This thesis attempts to answer the first question with a literature review of immersion programs, their excursions, and holistic/action-based foreign language acquisition; and the second question with an empirical study of excursions offered by an immersion program in Germany.

No description available.

One of the unsolved problems of modern science is whether the pre-Columbian peoples of the New World developed completely independently of cultural influences from the Old World or if there was a trans-oceanic contact? A number of scientists agree that there are many – and often remarkable – similarities between the cultures of pre-Columbian America and those of the Mediterranean world. Nevertheless, there is no agreement, as yet, on how cultural diffusion can be differentiated from independent invention. Scientific analysis shows that scholarly positions are often strongly pre-formed from paradigms (scientific based assumptions), which tend to hinder consideration of solid scientific data offered by geo-biology and its trans-disciplinary examination of the subject under investigation here. An unambiguous answer to the question, what historical processes led to the emergence of the ancient American agriculture, hasn\''t been given. However, the archaeological discovery of crops with clear trans-oceanic origin, in addition to advances in molecular biology, increasingly support the hypothesis that humans from the distant past influenced each other across the oceans at a much earlier stage. The vegetation and zoo-geography indicate, by numerous examples that some species could only have spread through perhaps unintentional (passive) human transmission [1]. There are two very old crops found in the „New World‟, which contradict the paradigm of a completely independent origin for American agriculture. These are the African Bottle Gourd (Lagenaria siceraria L.) and the ancestral cotton species (Gossypium herbaceum L.) of the domesticated spin able sub-genus of tetraploid cotton. The historical spread of both types has been under discussion for decades, especially in respect of trans-oceanic human contact with the American continent. There has also been a debate in the \"Old World\" ever since the discovery of nicotine and cocaine in Egyptian mummies, centering around whether \"New World\" plants (or the ingredients) might have been transmitted in the reverse direction, back to the presumed start in centers of the Ancient World\''s oldest civilizations.

Advanced scanning magnetoresistive microscopy (SMRM) — a robust magnetic imaging and probing technique — is presented. It utilizes conventional recording heads of a hard disk drive as sensors. The spatial resolution of modern tunneling magnetoresistive sensors is nowadays comparable with more commonly used magnetic force microscopes. Important advantages of SMRM are the ability to detect pure magnetic signals directly proportional to the out-of-plane magnetic stray field, negligible sensor stray fields, and the ability to apply local bipolar magnetic field pulses up to 10 kOe with bandwidths from DC up to 1 GHz. The performance assessment of this method and corresponding best practices are discussed in the first section of this work. An application example of SMRM, the study on chemically ordered L10 FePt is presented in a second section. A constructed heater unit of SMRM opens the path to investigate temperature-dependent magnetic properties of the medium by recording and imaging at elevated temperatures. L10 FePt is one of the most promising materials to reach limits in storage density of future magnetic recording devices based on heat-assisted magnetic recording (HAMR). In order to be implemented in an actual recording scheme, the medium Curie temperature should be lowered. This will reduce the power requirements, and hence, wear and tear on a heat source — integrated plasmonic antenna. It is expected that the exchange coupling of FePt to thin Fe layers provides high saturation magnetization and elevated Curie temperature of the composite. The addition of Cu allows adjusting the magnetic properties such as perpendicular magnetic anisotropy, coercivity, saturation magnetization, and Curie temperature. This should lead to a lowering of the switching field of the hard magnetic FeCuPt layer and a reduction of thermally induced recording errors. In this regard, the influence of the Fe layer thickness on the switching behavior of the hard layer was investigated, revealing a strong reduction for Fe layer thicknesses larger than the exchange length of Fe. The recording performance of single-layer and bilayer structures was studied by SMRM roll-off curves and histogram methods at temperatures up to 180 °C In the last section of this work, SMRM advantages are demonstrated by various experiments on a two-dimensional magnetic vortex lattice. Magnetic vortex is a peculiar complex magnetization configuration which typically appears in a soft magnetic structured materials. It consists of two coupled sub-systems: the core, where magnetization vector points perpendicular to the structure plane, and the curling magnetization where magnetic flux is rotating in-plane. The unique properties of a magnetic vortex making it an object of a great research and technological interest for spintronic applications in sensorics or data storage. Manipulation of the vortex core as well as the rotation sense by applying a local field pulse is shown. A spatially resolved switching map reveals a significant "write window" where vortex cores can be addressed correctly. Moreover, the external in-plane magnet extension unit allow analyzing the magnetic vortex rotational sense which is extremely practical for magnetic coupling investigations of magnetic coupling phenomena.

The docotoral thesis titled 'Modeling the effects of Transient Stream Flow on Solute Dynamics in Stream Banks and Intra-meander Zones' investigates flow and solute dynamcis across surface water-groundwater interface under dynamic flow conditons through numerical simulations. The abstract of the thesis is as follows: Waters from various sources meet at the interface between streams and groundwater. Due to their different origins, these waters often have contrasting chemical signatures and therefore mixing of water at the interface may lead to significant changes in both surface and subsurface water quality. The riparian zone adjacent to the stream serves as transition region between groundwater and stream water, where complex water and solute mixing and transport processes occur. Predicting the direction and the magnitude of solute exchanges and the extent of transformations within the riparian zone is challenging due to the varying hydrologic and chemical conditions as well as heterogeneous morphological features which result in complex, three-dimensional flow patterns. The direction of water flow and solute transport in the riparian zone typically varies over time as a result of fluctuating stream water and groundwater levels. Particularly, increasing groundwater levels can mobilize solutes from the unsaturated zone which can be subsequently transported into the stream. Such complex, spatially and temporally varying processes are hard to capture with field observations alone and therefore modeling approaches are required to predict the system behavior as well as to understand the role of individual factors. In this thesis, we investigate the inter-connectivity of streamthe s and adjacent riparia zones in the context of water and solute exchanges both laterally for bank storage and longitudinally for hyporheic flow through meander bends. Using numerical modeling, the transient effect of stream flow events on solute transport and transformation within the initially unsaturated part of stream banks and meander bends have been simulated using a systematic set of hydrological, chemical and morphological scenarios. A two dimensional variably saturated media groundwater modeling set up was used to explore solute dynamics during bank flows. We simulated exchanges between stream and adjacent riparian zone driven by stream stage fluctuations during stream discharge events. To elucidate the effect of magnitude and duration of discharge events, we developed a number of single discharge event scenarios with systematically varying peak heights and event duration. The dominant solute layer was represented by applying high solute concentration in upper unsaturated riparian zone profile. Simulated results show that bank flows generated by high stream flow events can trigger solute mobilization in near stream riparian soils and subsequently export significant amounts of solutes into the stream. The timing and amount of solute export is linked to the shape of the discharge event. Higher peaks and increased duration significantly enhance solute export, however, peak height is found to be the dominant control for overall lateral mass export. The mobilized solutes are transported towards the stream in two stages (1) by return flow of stream water that was stored in the riparian zone during the event and (2) by vertical movement to the groundwater under gravity drainage from the unsaturated parts of the riparian zone, which lasts for significantly longer time (> 400 days) resulting in a theoretically long tailing of bank outflows and solute mass outfluxes. Our bank flow simulations demonstrate that strong stream discharge events are likely to mobilize and export significant quantity of solutes from near stream riparian zones into the stream. Furthermore, the impact of short-term stream discharge variations on solute exchange may sustain for long times after the flow event. Meanders are prominent morphological features of stream systems which exhibit unique hydrodynamics. The water surface elevation difference across the inner bank of a meander induces lateral hyporheic exchange flow through the intrameander region, leading to solute transport and reactions within intra-meander region. We examine the impact of different meander geometries on the intra-meander hyporheic flow field and solute mobilization under both steady-state and transient flow conditions. In order to explore the impact of meander morphology on intrameander flow, a number of theoretical meander shape scenarios, representing various meander evolution stages, ranging from a typical initial to advanced stage (near cut off ) meander were developed. Three dimensional steady-state numerical groundwater flow simulations including the unsaturated zone were performed for the intra-meander region for all meander scenarios. The meandering stream was implemented in the model by adjusting the top layers of the modeling domain to the streambed elevation. Residence times for the intra-meander region were computed by advective particle tracking across the inner bank of meander. Selected steady state cases were extended to transient flow simulations to evaluate the impact of stream discharge events on the temporal behavior of the water exchange and solute transport in the intra-meander region. Transient hydraulic heads obtained from the surface water model were applied as transient head boundary conditions to the streambed cells of the groundwater model. Similar to the bank storage case, a high concentration of solute (carbon source) representing the dominant solute layer in the riparian profile was added in the unsaturated zone to evaluate the effect of stream flow event on mobilization and transport from the unsaturated part of intrameander region. Additionally, potential chemical reactions of aerobic respiration by the entry of oxygen rich surface water into subsurface as well denitrification due to stream and groundwater borne nitrates were also simulated. The results indicate that intra-meander mean residence times ranging from 18 to 61 days are influenced by meander geometry, as well as the size of the intra-meander area. We found that, intra-meander hydraulic gradient is the major control of RTs. In general, larger intra-meander areas lead to longer flow paths and higher mean intra-meander residence times (MRTs), whereas increased meander sinuosity results in shorter MRTs. The vertical extent of hyporheic flow paths generally decreases with increasing sinuosity. Transient modeling of hyporheic flow through meanders reveals that large stream flow events mobilize solutes from the unsaturated portion of intra-meander region leading to consequent transport into the stream via hyporheic flow. Advective solute transport dominates during the flow event; however significant amount of carbon is also consumed by aerobic respiration and denitrification. These reactions continue after the flow events depending upon the availability of carbon source. The thesis demonstrates that bank flows and intra-meander hyporheic exchange flows trigger solute mobilization from the dominant solute source layers in the RZ. Stream flow events driven water table fluctuations in the stream bank and in the intra-meander region transport substantial amount of solutes from the unsaturated RZ into the stream and therefore have significant potential to alter stream water quality.:Declaration Abstract Zusammenfassung 1 General Introduction 1.1 Background and Motivation 1.2 Hydrology and Riparian zones 1.2.1 Transport processes driven by fluctuation in riparian water table depth 1.2.1.1 Upland control 1.2.1.2 Stream control 1.2.2 Biochemical Transformations within the Riparian Zone 1.3 Types and scales of stream-riparian exchange 1.3.1 Hyporheic Exchange 1.3.1.1 Small Scale Vertical HEF 1.3.1.2 Large Scale lateral HEF 1.3.2 Bank Storage 1.4 Methods for estimation of GW-SW exchanges 1.4.1 Field Methods 1.4.1.1 Direct measurement of water flux 1.4.1.2 Tracer based Methods 1.4.2 Modeling Methods 1.4.2.1 Transient storage models 1.4.2.2 Physically based models 1.5 Research gaps and need 1.6 Objectives of the research 1.7 Thesis Outline 2 Flow and Transport Dynamics during Bank Flows 2.1 Introduction 2.2 Methods 2.2.1 Concept and modeling setup 2.2.2 Numerical Model 2.2.3 Stream discharge events 2.2.4 Model results evaluation 2.3 Results and discussion 2.3.1 Response of water and solute exchange to stream discharge events 2.3.1.1 Water exchange time scales 2.3.1.2 Stream water solute concentration 2.3.2 Solute mobilization within the riparian zone 2.3.3 Influence of peak height and event duration on solute mass export towards the stream 2.3.4 Effects of event hydrograph shape on stream water solute concentration 2.3.5 Model limitations and future studies 2.4 Summary and Conclusions Appendix 2 3 Flow and Transport Dynamics within Intra-Meander Zone 3.1 Introduction 3.2 Methods 3.2.1 Meander Shape Scenarios 3.2.2 Surface Water Simulations 3.2.3 3D Groundwater Flow Simulations with Modeling code MIN3P 3.2.3.1 Steady Flow Simulations 3.2.3.2 Stream flow event and Solute Mobilization Set-up 3.2.4 Reactive Transport 3.3 Results and Discussion 3.3.1 Groundwater heads and flow paths in the saturated intrameander zone 3.3.1.1 Groundwater heads 3.3.1.2 Flow paths and isochrones 3.3.1.3 Vertical extent of flow paths 3.3.2 Intra-Meander Residence Time Distribution 3.3.3 Factors affecting intra-meander flow and residence times 3.3.3.1 intra-meander hydraulic gradient 3.3.3.2 Maximum penetration depth 3.3.3.3 Meander sinuosity 3.3.3.4 intra-meander area (A) 3.3.4 Influence of Discharge Event on intra-meander Flow and Solute Transport 3.3.4.1 Spatial distribution of groundwater head and solute concentration 3.3.4.2 Time scales of intra-meander groundwater heads and solute transport 3.3.4.3 Solute export during stream discharge event 3.3.5 Intra-meander reactive transport during stream discharge event 3.3.5.1 Impact of stream discharge on aerobic respiration and denitrification 3.3.5.2 DOC mass removal during stream discharge event 3.4 Summary and Conclusions Appendix 3 4 General Summary and Conclusions 4.1 Summary 4.2 Conclusions 4.2.1 Flow and Transport Dynamics in Near Stream Riparian Zone (Bank Flows) 4.2.2 Flow and Transport Dynamics within Intra-Meander Zone 4.3 Model Limitations and Future Studies Bibliography Acknowledgement