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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
591

Altération de la physiologie des poissons exposés à des hydrocarbures aromatiques polycycliques (HAP) : comportement et reproduction / Long term physiological disruptions in fish after exposure to polycyclic aromatic hydrocarbons (PAHs) : behavior and reproduction

Vignet, Caroline 11 February 2014 (has links)
Les hydrocarbures aromatiques polycycliques (HAP) sont des polluants organiques persistants qui sont présents en mélange complexe dans l’environnement et notamment dans les milieux aquatiques. Ils s’adsorbent sur les particules en suspension, s’accumulent dans les sédiments et dans les premiers maillons de la chaîne trophique. L’objectif de cette étude était de mesurer les effets à long terme d’une contamination par des HAP chez un modèle de vertébrés : le poisson zèbre. Dans un premier temps, des embryons ont été exposés pendant les 4 premiers jours de leur développement sur du sédiment naturel enrobé de 3 HAP individuel (phénanthrène, pyrène et benzo[a]pyrène) puis transférés et élevés en eau propre. Dans un deuxième temps, des poissons ont été exposés par voie alimentaire tout au long du cycle de vie et dès le premier repas à 3 fractions de HAP à doses environnementales enrobées sur les aliments : une fraction pyrolytique (PY) extraite d’un sédiment échantillonné dans la Seine et deux fractions pétrogéniques (un fuel lourd (HO) provenant de l’Erika et un pétrole brut type Arabian light (LO)). Les effets à long terme sur la croissance, la survie, la reproduction et le comportement ont été évalués à différents âges. Ces effets ont pu être observés à plusieurs échelles, i.e. de la molécule, aux tissus et organes puis à l’échelle de l’individu. Globalement, chez les poissons contaminés, la croissance est ralentie, la survie larvaire diminuée chez les HO, la fonction reproduction est altérée fortement à la fois au niveau hormonal, tissulaire et phénotypique ainsi que les réponses comportementales léthargiques ou hyper-réactives selon les cas. L’exposition par voie sédimentaire a révélé des effets visibles lorsque les individus atteignaient 6 mois soulignant l’existence d’effets tardifs, notamment sur les réponses comportementales, d’une exposition très précoce y compris chez la descendance. Quant à l’exposition par voie alimentaire, elle a montré une gradation des effets. Toutes fonctions confondues, les résultats obtenus permettent d'établir une hiérarchie dans la toxicité des fractions étudiées : PY < LO ≈ HO. L'approche multi-échelle utilisée dans ce travail a permis, en partant d'informations acquises au niveau moléculaire, tissulaire et individuel, d'aboutir à une compréhension intégrée des conséquences qu'une exposition à des HAP peut avoir sur l'aptitude à la survie des poissons dans leur milieu naturel ainsi qu'à leur capacité à participer au renouvellement des générations futures. / Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants (POPs) which are found in complex mixtures in the environment including aquatic ecosystems. They adsorb on particles, accumulate in sediment and in the first link of the food web. The aim of this study was to measure long term effects of PAHs contamination on a vertebrate model : the zebrafish. In a first study, embryos were exposed on natural sediment spiked with 3 individual PAH (phenanthrene, pyrene and benzo[a]pyrene) during the first four days of their development. In a second study, to evaluate the consequences of long-term chronic exposure to PAHs, zebrafish were exposed, from their first meal (5 days post fertilisation) until they became reproducing adults, to diets spiked with three PAHs fractions at environmentally relevant concentrations (0.3X, 1X and 3X; with the 1X concentration being in the range of 4.6-6.7 μg.g-1 for total quantified PAHs). The fractions used were representative of PAHs of pyrolytic (PY) origin or of two different oils of differing compositions (a heavy fuel (HO) and a light crude oil (LO)). Long term effects on growth, survival, reproduction and behavior were evaluated at different ages. Effects were observed at molecule, tissue, organ and individual scales. In general, for contaminated fish, growth was reduced, larval survival decreased in HO, and reproduction was strongly impaired at hormonal, tissue and phenotypic levels, and behavioral responses were lethargic or hyperactive depending on fractions and stages. Sediment exposure still revealed visible effects when fish were 6 month old. These results hereby showed significant late effects, especially in behavioral responses after an early exposure, including in larvae issued from contaminated fish. In spiked diets contaminated fish, we observed a gradation of effects. Combining all functions, we established of hierarchy in toxicity in the studied fractions: PY < LO ≈ HO. Finally, our results gathered at a multiscale from molecule, to tissue and individuals, indicate that PAH mixtures of different compositions, representative of situations encountered in the wild, can promote lethal and sublethal effects which are likely to be detrimental for fish survival and recruitment into future generations.
592

Step-growth polymerization of perfluoro-vinyl ether, -cycloalkenes, and -acyclic alkenes with bisphenols containing variable polycyclic aromatic cores

Mukeba, Karl Mpumbwa 13 May 2022 (has links) (PDF)
This dissertation reports the synthesis and characterization of semi-fluorinated polymers derived from the polymerization of bisphenols with fluoroalkenes. A series of diverse bisphenols were chosen from popular commercial bisphenols and new polycyclic aromatic hydrocarbon (PAH) derived bisphenols requiring synthesis. Step-growth condensation polymerization of bisphenols with three different fluoroalkene types was performed while probing polymerization conditions and the structure/properties relationship of the resulting fluoropolymers. The fluoroalkene monomers were chosen from bis(trifluorovinyloxy)biphenyl (TFVE), perfluorocyclohexene (PFCH), and perfluoro acyclic monomers, namely, perfluoro(4-methyl-2-pentene) and 1-perfluoroheptene to undergo this chemistry. This work is divided into four parts based on the polymerization methodology. The first section focuses on the development of a new class of fluorinated arylene vinylene ether (FAVE) and their chain extended polymers prepared via base-catalyzed step-growth polymerization of PAH bisphenols with the TFVE monomer. These reactions afforded polymers containing controlled terminal and enchained fluoroalkenylenes for latent reactivity such as post polymerization functionalization, chain extension, and/or crosslinking. In general, these PAH cores resulted in polymers with improved thermal properties The second portion describes the investigation of step-growth addition/elimination polymerizations of PAH bisphenols and PFCH to prepare a new class of fluoropolymers containing alternating rigid PAH linkages and enchained PFCH vinylene ether moieties in the backbone. The third section covers the preparation and characterization of semi-fluorinated poly(aryl ether sulfone)s by nucleophilic addition/elimination reactions of PFCH with sulfone bisphenols. From commercially bisphenols combined with PAH bisphenols, we introduced the industrially valuable and property enhancing diaryl sulfone unit in a series of semi-fluorinated copolymers. This modular approach greatly expands access to partially fluorinated aryl ether sulfone polymers intended for high performance applications in optoelectronics, separation/purification membranes, and composites. Finally, in the fourth section, a new class of semifluorinated polymers was synthesized via nucleophilic addition/elimination reactions of acyclic perfluoroalkenes with bisphenols. In particular, environmental concerns for biopersistent and highly regulated perfluorooctanoic acid (PFOA) is the driver for using perfluoroheptene, which is derived cleanly by the decarboxylation of these pollutants in one step. This provided a new class of semi-fluorinated materials with promising properties including thermal stable, processability, and transparent film formation.
593

Degradation of Chlorinated Hydrocarbons in Groundwater Passing Through the Treatment Wetland at Wright-Patterson Air Force Base: Analysis of Results Collected During 2001-'06

Therrien, Annamarie F. January 2012 (has links)
No description available.
594

The IM-9 cell line: a model for evaluating TCDD-induced modulation of the polymorphic human hs1,2 enhancer within the 3' immunoglobulin heavy chain regulatory region

Chambers-Turner, Ruth C. 26 March 2010 (has links)
No description available.
595

Prediction of Retention Indices and Response Factors of Oxygenates for GC-FID by Multilinear Regression

Kretzschmar, Nils, Seifert, Markus, Busse, Oliver, Weigand, Jan J. 11 June 2024 (has links)
The replacement of fossil carbon sources with green bio-oils promotes the importance of several hundred oxygenated hydrocarbons, which substantially increases the analytical effort in catalysis research. A multilinear regression is performed to correlate retention indices (RIs) and response factors (RFs) with structural properties. The model includes a variety of possible products formed during the hydrodeoxygenation of bio-oils with good accuracy (RRF2 0.921 and RRI2 0.975). The GC parameters are related to the detailed hydrocarbon analysis (DHA) method, which is commonly used for non-oxygenated hydrocarbons. The RIs are determined from a paraffin standard (C5–C15), and the RFs are calculated with ethanol and 1,3,5-trimethylbenzene as internal standards. The method presented here can, therefore, be used together with the DHA method and be expanded further. In addition to the multilinear regression, an increment system has been developed for aromatic oxygenates, which further improves the prediction accuracy of the response factors with respect to the molecular constitution (R2 0.958). Both predictive models are designed exclusively on structural factors to ensure effortless application. All experimental RIs and RFs are determined under identical conditions. Moreover, a folded Plackett–Burman screening design demonstrates the general applicability of the datasets independent of method- or device-specific parameters.
596

Seismic structure, gas hydrate, and slumping studies on the Northern Cascadia margin using multiple migration and full waveform inversion of OBS and MCS data

Yelisetti, Subbarao 05 November 2014 (has links)
The primary focus of this thesis is to examine the detailed seismic structure of the northern Cascadia margin, including the Cascadia basin, the deformation front and the continental shelf. The results of this study are contributing towards understanding sediment deformation and tectonics on this margin. They also have important implications for exploration of hydrocarbons (oil and gas) and natural hazards (submarine landslides, earthquakes, tsunamis, and climate change). The first part of this thesis focuses on the role of gas hydrate in slope failure observed from multibeam bathymetry data on a frontal ridge near the deformation front off Vancouver Island margin using active-source ocean bottom seismometer (OBS) data collected in 2010. Volume estimates (∼ 0.33 km^3) of the slides observed on this margin indicate that these are capable of generating large (∼ 1 − 2 m) tsunamis. Velocity models from travel time inversion of wide angle reflections and refractions recorded on OBSs and vertical incidence single channel seismic (SCS) data were used to estimate gas hydrate concentrations using effective medium modeling. Results indicate a shallow high velocity hydrate layer with a velocity of 2.0 − 2.1 km/s that corresponds to a hydrate concentration of 40% at a depth of 100 m, and a bottom simulating reflector (BSR) at a depth of 265 − 275 m beneath the seafloor (mbsf). These are comparable to drilling results on an adjacent frontal ridge. Margin perpendicular normal faults that extend down to BSR depth were also observed on SCS and bathymetric data, two of which coincide with the sidewalls of the slump indicating that the lateral extent of the slump is controlled by these faults. Analysis of bathymetric data indicates, for the first time, that the glide plane occurs at the same depth as the shallow high velocity layer (100±10 mbsf). In contrast, the glide plane coincides with the depth of the BSR on an adjacent frontal ridge. In either case, our results suggest that the contrast in sediments strengthened by hydrates and overlying or underlying sediments where there is no hydrate is what causing the slope failure on this margin. The second part of this dissertation focuses on obtaining the detailed structure of the Cascadia basin and frontal ridge region using mirror imaging of few widely spaced OBS data. Using only a small airgun source (120 cu. in.), our results indicate structures that were previously not observed on the northern Cascadia margin. Specifically, OBS migration results show dual-vergence structure, which could be related to horizontal compression associated with subduction and low basal shear stress resulting from over-pressure. Understanding the physical and mechanical properties of the basal layer has important implications for understanding earthquakes on this margin. The OBS migrated image also clearly shows the continuity of reflectors which enabled the identification of thrust faults, and also shows the top of the igneous oceanic crust at 5−6 km beneath the seafloor, which were not possible to identify in single-channel and low-fold multi-channel seismic (MCS) data. The last part of this thesis focuses on obtaining detailed seismic structure of the Vancouver Island continental shelf from MCS data using frequency domain viscoacoustic full waveform inversion, which is first of its kind on this margin. Anelastic velocity and attenuation models, derived in this study to subseafloor depths of ∼ 2 km, are useful in understanding the deformation within the Tofino basin sediments, the nature of basement structures and their relationship with underlying accreted terranes such as the Crescent and the Pacific Rim terranes. Specifically, our results indicate a low-velocity zone (LVZ) with a contrast of 200 m/s within the Tofino basin sediment section at a depth 600 − 1000 mbsf over a lateral distance of 10 km. This LVZ is associated with high attenuation values (0.015 − 0.02) and could be a result of over pressured sediments or lithology changes associated with a high porosity layer in this potential hydrocarbon environment. Shallow high velocities of 4 − 5 km/s are observed in the mid-shelf region at depths > 1.5 km, which is interpreted as the shallowest occurrence of the Eocene volcanic Crescent terrane. The sediment velocities sharply increase about 10 km west of Vancouver Island, which probably corresponds to the underlying transition to the Mesozoic marine sedimentary Pacific Rim terrane. High attenuation values of 0.03 − 0.06 are observed at depths > 1 km, which probably corresponds to increased clay content and the presence of mineralized fluids. / Graduate / 0373 / 0372 / 0605 / subbarao@uvic.ca
597

A design of experiments approach for engineering carbon metabolism in the yeast Saccharomyces cerevisiae

Brown, Steven Richard January 2016 (has links)
The proven ability to ferment Saccharomyces cerevisiae on a large scale presents an attractive target for producing chemicals and fuels from sustainable sources. Efficient and predominant carbon flux through to ethanol is a significant engineering issue in the development of this yeast as a multi-product cell chassis used in biorefineries. In order to evaluate diversion of carbon flux away from ethanol, combinatorial deletions were investigated in genes encoding the six isozymes of alcohol dehydrogenase (ADH), which catalyse the terminal step in ethanol production. The scarless, dominant and counter- selectable amdSYM gene deletion method was optimised for generation of a combinatorial ADH knockout library in an industrially relevant strain of S. cerevisiae. Current understanding of the individual ADH genes fails to fully evaluate genotype-by-genotype and genotype-by-environment interactions: rather, further research of such a complex biological process requires a multivariate mathematical modelling approach. Application of such an approach using the Design of Experiments (DoE) methodology is appraised here as essential for detailed empirical evaluation of complex systems. DoE provided empirical evidence that in S. cerevisiae: i) the ADH2 gene is not associated with producing ethanol under anaerobic culture conditions in combination with 25 g l-1 glucose substrate concentrations; ii) ADH4 is associated with increased ethanol production when the cell is confronted with a zinc-limited [1 μM] environment; and iii) ADH5 is linked with the production of ethanol, predominantly at pH 4.5. A successful metabolic engineering strategy is detailed which increases the product portfolio of S. cerevisiae, currently used for large-scale production of bioethanol. Heterologous expression of the cytochrome P450 fatty acid peroxygenase from Jeotgalicoccus sp., OleTJE, fused to the RhFRED reductase from Rhodococcus sp. NCIMB 978 converted free fatty acid precursors to C13, C15 and C17 alkenes (3.81 ng μl-1 total alkene concentration).
598

Poröse Koordinationspolymere mit Linkern auf Basis Polycyclischer Aromatischer Kohlenwasserstoffe / Porous Coordination Polymers with Linkers Based on Polycyclic Aromatic Hydrocarbons (An Aromatic Leipzig Potpourri)

Zaake-Hertling, Haldor 21 September 2016 (has links) (PDF)
Zusammenfassung In der vorliegenden Promotionsschrift werden Strategien zur Erzeugung von Linkermolekülen beschrieben, die geeignet sind, um als Bauelemente für sogenannte \"Metal-Organic rameworks\" (MOF) eingesetzt zu werden. Diese Stoffe bestehen aus einem organischen \"Linker\"-Teil, welcher die Metalleinheiten (\"Sekundäre Baueinheit\", SBU) miteinander verbindet, und dadurch die Entstehung von dreidimensionalen porösen Netzwerken ermöglicht. Dieses Projekt wurde an der Universität Leipzig in der Arbeitsgruppe von Prof. Dr. rer. nat. Dr. h.c. Evamarie Hey-Hawkins am Institut für Anorganische Chemie durchgeführt. Seit den frühen neunziger Jahren genießen MOFs großes Interesse aufgrund ihrer besonderen Eigenschaften als Festkörper mit wohldefinierter und permanenter Porosität. In der Einleitung dieser Promotionsschrift werden das Anwendungspotential oder bereits existierende Anwendungen für MOFs und verwandte poröse Feststoffe näher beschrieben. Mögliche Anwendungsgebiete sind unter anderem Gasspeicherung, Trennverfahren, zur Katalyse, in der Medizin und für Detektoren in der analytischen Chemie. Die Auswahl der organischen Baueinheiten für die Synthese von MOFs richtet sich nach Kriterien wie z.B. thermischer Stabilität, Geometrie der koordinierenden Einheiten, Rigidität des Linkermoleküls. Weiterhin können potentielle sekundäre Effekte berücksichtigt werden, z.B. Eignung für katalytische Prozesse, Ladungspufferung oder Lichtsammelvermögen. Alle Linker enthalten aromatische Einheiten; es werden Anthracen, Binaphthyl (verkörpert durch chirale BINAPO-Einheiten), Biphenyl, Pyren und Perylen als Mittelstück des Linkers eingesetzt. Die Promotionsschrift beleuchtet auch in einem Streifblick die Geschichte, das Vorkommen, mögliche Anwendungen und Giftigkeit von Molekülen mit polycyclischen aromatischen Kohlenwasserstoffgruppen. Die Synthese der Linker wurde mittels der folgenden Route realisiert: Bromierung der aromatischen Bestandteile und Anfügen von Endstücken (\"capper\") - welche die koordinierenden Einheiten enthalten - durch die Suzuki-Miyaura-Kupplung. Die Syntheserouten für den bromierten aromatischen Mittelteil des Linkers, die Boronsäuren und die vollständigen Linker, werden im experimentellen Teil beschrieben, und die erhaltenen Linker werden charakterisiert. Für den anorganischen Teil des MOF wurden außerdem ausgewählte komplexe Einheiten erzeugt, die als Startmaterialien für den sogenannten \"controlled SBU approach\" (CSA) dienen. Bei dieser Methode wird eine Baueinheit erzeugt, die der gewünschten eigentlichen Baueinheit im fertiggestellten MOF ähnlich ist und dann als Präkursor in der Synthese eingesetzt wird. Verschiedene Ansätze zur Erzeugung von MOFs wurden ausgeführt: Langsame Diffusion in Flüssigkeiten oder Gelen und vor allem Tempern der organischen und anorganischen Baueinheiten oder Startmaterialien in einem Lösungsmittel, teilweise unter solvothermalen Bedingungen. Mehrere Polymere wurden in einer zur Röntgenstrukturbestimmung geeigneten kristallinen Form erhalten. Die Strukturen werden in der vorliegenden Arbeit präsentiert und diskutiert. Ein Ausblick auf weiterführende Untersuchungen an diesen Verbindungen wird ebenfalls gegeben. / Abstract This thesis describes approaches to obtain linker molecules that are suitable to build a so-called \"metal-organic framework\", MOF (or porous coordination polymer, PCP). These materials consist of an organic linker part that connects the metal units, \"secondary building units\" (SBU), with each other to form threedimensional, hollow networks. This project was performed at the University of Leipzig in the multinational workgroup of Prof. Dr. rer. nat. Dr. h.c. Evamarie Hey-Hawkins, at the Faculty for Inorganic Chemistry. These MOF materials have gained a lot of interest since the early 1990s for their special properties as solid materials with a well-defined, permanent porosity. The introductory part of this thesis elaborates potential or already current usage of MOF materials and related porous solids, such as gas storage, separation processes, catalysis, medical use and use in analytic detection. The choice of organic building blocks for the synthesis of MOFs followed certain criteria, such as thermal stability, geometry of coordinating units, rigidity of the linker molecule, and potential secondary effects such as suitability for catalytic purposes, charge buffering or light harvesting. All linkers feature aromatic units, and among the cores are moieties like anthracene, binaphthyl (represented by the chiral BINAP), biphenyl, pyrene and perylene. A glance is thrown on the history, occurrence, possible use and potential toxicity of molecules with polycyclic aromatic hydrocarbon moieties. Synthesis of the linkers is implemented by use of brominations of the aromatic core units and attaching capper units - carrying the coordinating units - by means of Suzuki-Miyaura-coupling. The synthesis routes to these molecules, brominated aromatic core, boronic acids and finished linkers, are described in the experimental part. The obtained linkers are characterised and described. Furthermore, selected complex units for the inorganic part of a potential MOF were created as starting materials for a so-called \"controlled SBU approach\" (CSA); wherein a building block, very similar to the desired unit in the final framework, is prepared and then used as a precursor in the synthesis. Various attempts at the generation of MOFs were conducted: Slow diffusion in liquids or gels, and, especially, reactions by tempering the organic and inorganic building blocks or starting materials in a solvent - partially also under solvothermal conditions. Several polymers were obtained in crystalline form, suitable for structure determination by X-ray crystallography. These structures are presented and discussed in this work, as well as the further research on these solids and the results being achieved.
599

Poröse Koordinationspolymere mit Linkern auf Basis Polycyclischer Aromatischer Kohlenwasserstoffe: Ein aromatisches Leipziger Allerlei

Zaake-Hertling, Haldor 22 June 2016 (has links)
Zusammenfassung In der vorliegenden Promotionsschrift werden Strategien zur Erzeugung von Linkermolekülen beschrieben, die geeignet sind, um als Bauelemente für sogenannte \"Metal-Organic rameworks\" (MOF) eingesetzt zu werden. Diese Stoffe bestehen aus einem organischen \"Linker\"-Teil, welcher die Metalleinheiten (\"Sekundäre Baueinheit\", SBU) miteinander verbindet, und dadurch die Entstehung von dreidimensionalen porösen Netzwerken ermöglicht. Dieses Projekt wurde an der Universität Leipzig in der Arbeitsgruppe von Prof. Dr. rer. nat. Dr. h.c. Evamarie Hey-Hawkins am Institut für Anorganische Chemie durchgeführt. Seit den frühen neunziger Jahren genießen MOFs großes Interesse aufgrund ihrer besonderen Eigenschaften als Festkörper mit wohldefinierter und permanenter Porosität. In der Einleitung dieser Promotionsschrift werden das Anwendungspotential oder bereits existierende Anwendungen für MOFs und verwandte poröse Feststoffe näher beschrieben. Mögliche Anwendungsgebiete sind unter anderem Gasspeicherung, Trennverfahren, zur Katalyse, in der Medizin und für Detektoren in der analytischen Chemie. Die Auswahl der organischen Baueinheiten für die Synthese von MOFs richtet sich nach Kriterien wie z.B. thermischer Stabilität, Geometrie der koordinierenden Einheiten, Rigidität des Linkermoleküls. Weiterhin können potentielle sekundäre Effekte berücksichtigt werden, z.B. Eignung für katalytische Prozesse, Ladungspufferung oder Lichtsammelvermögen. Alle Linker enthalten aromatische Einheiten; es werden Anthracen, Binaphthyl (verkörpert durch chirale BINAPO-Einheiten), Biphenyl, Pyren und Perylen als Mittelstück des Linkers eingesetzt. Die Promotionsschrift beleuchtet auch in einem Streifblick die Geschichte, das Vorkommen, mögliche Anwendungen und Giftigkeit von Molekülen mit polycyclischen aromatischen Kohlenwasserstoffgruppen. Die Synthese der Linker wurde mittels der folgenden Route realisiert: Bromierung der aromatischen Bestandteile und Anfügen von Endstücken (\"capper\") - welche die koordinierenden Einheiten enthalten - durch die Suzuki-Miyaura-Kupplung. Die Syntheserouten für den bromierten aromatischen Mittelteil des Linkers, die Boronsäuren und die vollständigen Linker, werden im experimentellen Teil beschrieben, und die erhaltenen Linker werden charakterisiert. Für den anorganischen Teil des MOF wurden außerdem ausgewählte komplexe Einheiten erzeugt, die als Startmaterialien für den sogenannten \"controlled SBU approach\" (CSA) dienen. Bei dieser Methode wird eine Baueinheit erzeugt, die der gewünschten eigentlichen Baueinheit im fertiggestellten MOF ähnlich ist und dann als Präkursor in der Synthese eingesetzt wird. Verschiedene Ansätze zur Erzeugung von MOFs wurden ausgeführt: Langsame Diffusion in Flüssigkeiten oder Gelen und vor allem Tempern der organischen und anorganischen Baueinheiten oder Startmaterialien in einem Lösungsmittel, teilweise unter solvothermalen Bedingungen. Mehrere Polymere wurden in einer zur Röntgenstrukturbestimmung geeigneten kristallinen Form erhalten. Die Strukturen werden in der vorliegenden Arbeit präsentiert und diskutiert. Ein Ausblick auf weiterführende Untersuchungen an diesen Verbindungen wird ebenfalls gegeben.:(s. PDF ab S. 9 (PDF-Seite)) 1 Vorwort S. 1 2 Polycyclische aromatische Kohlenwasserstoffe S. 2 3 Poröse Festkörpermaterialien S. 20 4 Auswahl / Design der Linkermoleküle S. 50 5 Experimenteller Teil S. 65 6 Diskussion der Ergebnisse S. 194 7 Danksagung S. 293 8 Literaturverzeichnis S. 299 9 Anhang (X-Ray, NMR, DTA-TG, UV-Vis) S. 328 / Abstract This thesis describes approaches to obtain linker molecules that are suitable to build a so-called \"metal-organic framework\", MOF (or porous coordination polymer, PCP). These materials consist of an organic linker part that connects the metal units, \"secondary building units\" (SBU), with each other to form threedimensional, hollow networks. This project was performed at the University of Leipzig in the multinational workgroup of Prof. Dr. rer. nat. Dr. h.c. Evamarie Hey-Hawkins, at the Faculty for Inorganic Chemistry. These MOF materials have gained a lot of interest since the early 1990s for their special properties as solid materials with a well-defined, permanent porosity. The introductory part of this thesis elaborates potential or already current usage of MOF materials and related porous solids, such as gas storage, separation processes, catalysis, medical use and use in analytic detection. The choice of organic building blocks for the synthesis of MOFs followed certain criteria, such as thermal stability, geometry of coordinating units, rigidity of the linker molecule, and potential secondary effects such as suitability for catalytic purposes, charge buffering or light harvesting. All linkers feature aromatic units, and among the cores are moieties like anthracene, binaphthyl (represented by the chiral BINAP), biphenyl, pyrene and perylene. A glance is thrown on the history, occurrence, possible use and potential toxicity of molecules with polycyclic aromatic hydrocarbon moieties. Synthesis of the linkers is implemented by use of brominations of the aromatic core units and attaching capper units - carrying the coordinating units - by means of Suzuki-Miyaura-coupling. The synthesis routes to these molecules, brominated aromatic core, boronic acids and finished linkers, are described in the experimental part. The obtained linkers are characterised and described. Furthermore, selected complex units for the inorganic part of a potential MOF were created as starting materials for a so-called \"controlled SBU approach\" (CSA); wherein a building block, very similar to the desired unit in the final framework, is prepared and then used as a precursor in the synthesis. Various attempts at the generation of MOFs were conducted: Slow diffusion in liquids or gels, and, especially, reactions by tempering the organic and inorganic building blocks or starting materials in a solvent - partially also under solvothermal conditions. Several polymers were obtained in crystalline form, suitable for structure determination by X-ray crystallography. These structures are presented and discussed in this work, as well as the further research on these solids and the results being achieved.:(s. PDF ab S. 9 (PDF-Seite)) 1 Vorwort S. 1 2 Polycyclische aromatische Kohlenwasserstoffe S. 2 3 Poröse Festkörpermaterialien S. 20 4 Auswahl / Design der Linkermoleküle S. 50 5 Experimenteller Teil S. 65 6 Diskussion der Ergebnisse S. 194 7 Danksagung S. 293 8 Literaturverzeichnis S. 299 9 Anhang (X-Ray, NMR, DTA-TG, UV-Vis) S. 328

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