Thesis (Ph. D.)--University of Texas at Dallas, 2007. / Includes vita. Includes bibliographical references (leaves 78-80)

La thèse commence le 1er octobre 2012. IL s'agit pour cette première année de thèse de synthétiser différents complexes de coordination a base du Ruthénium, Fer, Manganèse et de Cobalt à ligands polypyridinique. Ces complexes seront ensuite assemblés par lien covalent. Nous proposons d'utiliser entre autre les techniques d'electrochimie pour induire ces couplages. On cherchera aussi a immobiliser les assemblages sur surface. La principale difficulté attendue dans cette etape du travail concerne la fonctionalisation dissymétrique des ligands pour l'obtention de triade. / This thesis deals with the synthesis and characterization of inorganic triads for photoinduced charge separation. A range of photosensitizers will be studied, and the effect of the donor and acceptor will be assesed as well. These systems will be studied in solution and immobalized on surfaces. Cette thèse traite de la synthèse et la caractérisation des triades inorganiques pour la séparation de charge photoinduite. Une gamme de photosensibilisateurs seront étudiées, et l'effet du donneur et accepteur sera ainsi étudié. Ces systèmes seront étudiés en solution et immobalizes sur les surfaces.

La carbonylation du méthanol pour fabriquer de l'acide acétique est probablement l'un des procédés de catalyse homogène les plus utilisés par l'industrie chimique. La production d'acide acétique atteint aujourd'hui plus de 8 millions de tonnes par an et celui‐ci est majoritairement utilisé comme point de départ de la production de monomère d'acétate de vinyle, d'anhydride acétique ou dans la purification d'acide téréphtlique. La demande mondiale en acide acétique, qui admet une croissance annuelle régulière de 2,4 % a conduit de nombreux laboratoires, publics comme privés, à développer un procédé qui soit peu gourmand en énergie (basse pression et basse température) ainsi que sélectif. En 1960, la compagnie BASF a mis au point un procédé utilisant à 680 bar du cobalt en présence d'un promoteur iodé comme catalyseur, qui a été supplanté peu de temps après par un système utilisant le complexe de rhodium [RhI2(CO)2] comme catalyseur, développé par la compagnie Monsanto. La société Celanese a nettement amélioré ce dernier procédé en ajoutant de grandes quantités d'iodure de lithium (Lil), abaissant ainsi la teneur en eau nécessare de 14% à 4% . Cette réduction significative de la teneur en eau a conduit à un gain d'énergie considérable utilisée pour la séparation de l'eau et de l'acide acétique. En 1996, la compgnie BP Chemical a proposé un nouveau procédé à basse teneur en eau basé sur un catalyseur d'iridium en présence d'un complexe du ruthénium comme co‐catalyseur, connu sous le nom de procédé Cativa®. Nous analysons dans ce mémoire l'effet positif du complexe du rhodium [RhI(CO)2]2 sur l'étape déterminante du cycle catalytique de l'iridium qui intervient dans la carbonylation du méthanol en acide acétique. Des analyses en RMN sous pression de monoxyde de carbone nous apportent des informations tant sur le rôle de l'eau que celui du sel Lil sur l'étape d'élimination réductrice, étape ultime du cycle catalytique du rhodium. Une étude cinétique, effectuée en spectrométrie infra‐rouge, nous permet de mettre en avant l'importance que joue l'anion acétate sur cette dernière étape et de proposer l'utilisation d'un co‐catalyseur organométallique, évitant ainsi l'ajout d'iodure de lithium dans le procédé Celanese à basse teneur en eau.

Abstract Human motor performance and motor skills are essential aspects of various daily activities, and their importance is especially great in traffic, sports and unexpected situations. There is evidence that physically active subjects have better performance in some motor tasks (e.g. reaction time) than less active ones, and a few longitudinal intervention studies have shown that training improves certain aspects of motor performance, but there are also contradictory results. Despite the difficulty of improving motor performance, many physiotherapy programs and treatments are expected to do precisely that. However, the previous literature contains little information on these issues. The aim of the present doctoral project was to examine human motor performance (reaction time, speed of movement, tapping speed and coordination) and the effects of some of the most commonly used physiotherapy treatments on it in normal healthy volunteers. In addition, the reliability of the motor performance measurements performed with the HPM/BEP system is presented. Study I was a cross-sectional study of the population of Oulu, where 200 healthy randomly selected subjects (100 men and 100 women aged 21–70 years) were stratified by gender and by ten-year age group into ten groups. The test battery consisted of six motor performance tests for both hands and feet. The studies II, III and V were non-controlled intervention studies, and study IV was a cross-over intervention study. The participants in the studies were healthy, voluntary staff members (n = 14–30) of the Oulu University Hospital, and the interventions between the measurements consisted of strapping of the ankle and wrist joints (study II), hot and cold pack treatments of the hand (study III), one-hour hand strength training session (study IV) and a ten -week hand strength training program (study V). The results showed that motor performance was poorer in the older age groups in both genders. The average speed of movement and tapping speed values were higher for men than for women, but there were no gender differences in the coordination tests or the hand reaction time tests. All values (except the hand reaction times) were better for the dominant than the nondominant side. The strapping of the ankle and wrist joints decreased some aspects of the motor performance and muscle strength of these joints in healthy subjects. The hot pack treatment of healthy subjects caused only minor changes in the motor performance of the treated area, while the cold pack treatment decreased almost all of the measured aspects, and these changes were especially notable in fine motor movements. A one-hour hand strength training session decreased acutely muscle strength and EMG activity, but muscle fatigue had no effects on the motor performance functions of the hand. It seems that the feeling of incompetence to perform speed and accurate movements with fatigued muscles is mainly a subjective feeling, and that the real effect of muscle fatigue on motor performance is less than generally expected. A ten-week hand strength training period increased muscle strength and EMG activity in the trained muscles. There was also a suggestion that even non-task-specific training may improve some aspects of the motor performance of the hand, and an increase in the activation of motor units during muscle contraction may improve motor performance in some motor tasks. In addition, the results indicated that the HPM / BEP system is a potentially useful tool for studying motor performance, and the reliability of the system is acceptable.

The object of this analysis of the Southern African Development Coordination Conference (SADCC) was to examine the interaction between the states which comprise the organisation in terms of regional and international factors which either facilitated or constrained the pursuit of the organisation's economic goals. To this end a theoretical orientation which would place the organisation in context of regional and international political and economic interaction was necessary. International regime theory was used to place the organisation in an international context, and at the same time provided a theoretical dimension which could be used to analyse empirical evidence on the SADCC organisation's functioning. The application of regime theory clearly highlighted the fact that SADCC's economic goals are constrained by the degree to which all of the SADCC states are integrated on the economic level with western market economy and furthermore , by the fact that these links are reinforced for seven of the nine SADCC states by their economic dependence on South Africa. The above conclusion showed that in terms of the perpetuation of the SADCC organisation as an economic regime, according to the regime theory outlined in Chapter One, the goals of SADCC did not create a firm basis for economic cooperation in the long term. The future of the SADCC organisation in it's present form will depend on how long the racial policies of South Africa continue, for the analysis makes clear that the organisation has much more political than economic coherency. The use of a regime framework showed that in terms of the SADCC states individual economic positions, the historical and structural links between South Africa, the majority of the SADCC states and the West will continue indefinitely due to the strength of the structural economic links between the Southern African region and the western market economy. Thus the analysis proves, within the parameters of international regime theory, the lack of economic coherency within the SADCC organisation's goals, and the strength of the economic ties between the Southern African region and the West.

M.Sc. (Chemistry) / Please refer to full text to view abstract

The structures of four compounds representing each of the organic (natural product), inorganic and organometallic classes of compounds have been determined by single-crystal X-ray diffraction, and the methods employed in solution of the structures have been discussed briefly. For all four structures, the intensity data were collected on a single-crystal diffractometer with [formula omitted] radiation and a scintillation counter. The structure of the alkaloid, daphmacrine methiodide (acetone solvate), was determined from heavy-atom Patterson and Fourier syntheses, and refined by block-diagonal least-squares methods to a final R value of 0.089 for 1834 observed reflections. The absolute configuration was determined by the anomalous dispersion method. The molecule consists of two cage-structures which are linked by a chain of two carbon atoms, and the bond lengths and valency angles do not differ from normal values. 2 4-, For both exo-tricyclo [formula omitted] silver nitrate and silver nitrate itself, the silver ion was determined from Patterson syntheses to be lying in a pseudo-special position, so that the resulting electron-density maps exhibited pseudo-symmetry. A trial-and-error method based on detailed study of the shape of the Ag-Ag Patterson peaks was adopted to find the exact location of the silver ions, and from the resulting electron-density maps the true light atom peaks could be discerned from their images. The refinement was carried out by full-matrix least-squares, and the final R for the complex of silver nitrate was 0.105 and for silver nitrate was 0.067. The structure of the complex consists of thick layers perpendicular to the a crystallographic axis, and separated by ½ a. The silver ion is coordinated roughly tetrahedrally to the double bond of the hydrocarbon (in the exo-position, [formula omitted]), and to three nitrate groups [formula omitted]. The layers are held together by van der Waals forces. The silver nitrate structure consists of layers of silver ions parallel to the b crystallographic axis, and separated by ½ b, with the nitrate groups bridging the gap between layers. Previously observed inequalities in the N—O distances have been removed, all three bond lengths in the nitrate ion being 1.26 (l)Ǻ. The anisotropic thermal motion has been described. The N,N-dimethyl(ferrocenylmethyl)ammonium tetrachlorozincate hydrate structure contains seven heavy atoms, and it was not possible to resolve the Patterson peaks because of the overlap. A direct sign-determining procedure was employed to locate the heavy atoms, and the light atoms were located from resulting electron-density maps. The structure was refined to a final R value of 0.068 for 2012 observed reflections. The mean bond distances are Fe-C = 2. 04Ǻ and C-C (cyclopentadienyl rings) = 1.43Ǻ. Groups of four cations, two anions and two water molecules (two formula units), are linked around centres of symmetry by N-H...Cl (3.11Ǻ), N-H...0 (2.76Ǻ) and 0-H...Cl (3.05, 3.17Ǻ) hydrogen bonds. / Science, Faculty of / Chemistry, Department of / Graduate

Abstract: The choice ofsuitable ligand platforms is crucial to organometallic coordination chemistry and homogeneous catalysis. Among the various ligand platforms available, pincer ligands offer a convenient route to manipulate the properties of the resulting complexes. The pincer chemistry of rhodium has attracted attention for over 40 years, and Rh complexes are dominated by Rh(I) and Rh(III) low-spin states, thus they are more predictable than other paramagnetic species. Compared to other pincer ligand platforms, pyridine-based pincer complexes are particularly attractive as they exhibit diverse reactivities. Our group realized a new class of the PN3 (P) pincer system, with altered the unique catalytic performances, thermodynamic and kinetic properties due to their pseudo-dearomatized nature. In Chapter 2, selective carbonylation of benzene to benzaldehyde using a phosphorus nitrogen PN3P Rh(I) complex was realized. The PN3P Rh pincer chloride complex cPePN3PRhCl was capable of activating C−H bond of benzene to give the phenyl complex cPePN3PRh(C6H5) using KN(SiMe3)2 as a base. Furthermore, the benzoyl complex cPePN3PRh(CO)(C6H5) was obtained by treating a benzene solution of cPePN3PRh(C6H5) with CO gas. In dilute HCl, a high yield of 90% benzaldehyde was formed with regeneration of the cPePN3PRhCl. This is the first example of selective carbonylation of benzene into benzaldehyde accomplished by directly inserting CO without irradiation. In Chapter 3, the ligand-centered reactivity of a pseudo-dearomatized PN3P *rhodium complex towards molecular oxygen wasrealized. For the dearomatized rhodium carbonyl complex (tBuPN3P*RhCO), one of the C−H bonds of the pseudo-dearomatized pyridine ring was oxidized by O2 to create an α, β-unsaturated carbonyl functionality. Moreover, the resulting metal complex with the post-modified PN3P ligand could react with thiophenol and 4-methylaniline to afford the corresponding oxidative Michael addition products. In Chapter 4, to further explore the ligand-centered reactivity of tBuPN3P *RhCO, a series of second-generation diimine-amido PN3P-pincer carbonyl complexes were synthesized by reaction of tBuPN3P*RhCO and various alkyl/benzyl halides via a post-modification strategy, and these complexes were well characterized by NMR, HRMS, FT-IR, and single crystal diffraction. Moreover, a plausible mechanism for the formation of 2nd -generation PN3P complexes was proposed

Cette thèse est consacrée à la synthèse et à la caractérisation physique de nouveaux polymères de coordination bidimensionnels (2D) possédant un ordre magnétique et/ou une conductivité électrique à haute température. La présence simultanée de ces deux propriétés au sein d'un même matériau représente un formidable défi pour la synthèse de matériaux multifonctionnels utilisables dans le traitement et le stockage des données de nouvelles générations. Notre approche pour synthétiser de tels systèmes implique l'utilisation du ligand pontant organique redox-actif pyrazine, et de métaux de transition réducteurs. Le chapitre I présente quelques aspects généraux sur la chimie redox, la délocalisation des charges et la valence mixte qui sont essentiels à la compréhension des résultats expérimentaux. Les différentes approches de synthèse de polymères de coordination conducteurs et magnétiques sont également décrites. Le chapitre II donne un aperçu général des concepts fondamentaux concernant la conductivité électrique, le magnétisme et la spectroscopie d'absorption des rayons X. Le chapitre III analyse la synthèse et la caractérisation physique du composé CrCl2(pyrazine)2 présentant à la fois un ordre magnétique et une conductivité électrique. Les chapitres IV et V sont consacrés à l'étude de nouveaux composés MX2(pyrazine)2 en faisant varier M (Ti, V) et X (OSO2CH3, Br et I). L’objectif est de déterminer l’effet de la nature du centre métallique et du ligand axial sur les propriétés magnétiques et électriques. Enfin, le chapitre VI illustre comment la chimie redox post-synthétique peut entraîner une augmentation impressionnante de la température de l'ordre magnétique dans les matériaux 2D à base de pyrazine. / This thesis is devoted to the synthesis and physical characterization of new two-dimensional (2D) coordination polymers that present high-temperature magnetic order and/or electrical conductivity. The simultaneous implementation of these two properties within a single material represents a formidable challenge in the synthesis of multifunctional materials for next-generation data processing and storage. Our approach to synthesize such systems involves the use of the redox-active organic bridging ligand, pyrazine, and reducing transition metals. Chapter I presents some general aspects of redox-activity, charge delocalization and mixed-valency that are crucial for the understanding of the experimental results. The different approaches for the synthesis of conducting and magnetic coordination polymers are also described. Chapter II provides a general view on the fundamental concepts regarding electrical conductivity, magnetism and X-ray absorption spectroscopy. Chapter III deals with the synthesis and extensive physical characterization of the coordination solid CrCl2(pyrazine)2, which exhibits both magnetic order and electrical conductivity. Chapters IV and V are devoted to the study of the effect of the anionic co-ligands and metal centers, respectively, in the family of MX2(pyrazine)2 (M = Cr, Ti, V and X = OSO2CH3, Br and I) coordination solids. Finally, Chapter VI illustrates how post-synthetic redox chemistry can result in an impressive enhancement of the magnetic order temperature in 2D layered pyrazine-based materials.

Sustainability has consolidated as a global paradigm. Consequently, different sectors have adopted its principles to develop better practices for the environment and society. Within the transportation field, carsharing has emerged as a potential solution to reduce congestion and carbon emissions.  In Stockholm, one of the world’s leading cities on the sustainability agenda, carsharing has been growing steadily, with more companies participating in the market and more users adopting it. Likewise, the local administration conceives it as a tool that could contribute to sustainability. However, the private and the public sector assert that carsharing is far from its potential. The conditions established by the local government could be a factor that explains this situation.  Accordingly, this thesis aims to analyze Stockholm’s policy and administrative framework for carsharing, with a focus on its coordination and implementation. This was made by conducting interviews with public officers and carsharing companies and by analyzing Stockholm’s policy and administrative documents related to carsharing through the lens of policy integration and coordination. The illustrative example of charging stations and its implications for carsharing is used to analyze policy coherence, and to reveal the implementation divergences between the private carsharing sector and local public authorities.