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1
Fondement, Valentin. "Conception d'une sonde diagraphique neutronique dans le cadre de l'exploration et de l'exploitation minière de l'uranium." Electronic Thesis or Diss., Université Grenoble Alpes, 2023. http://www.theses.fr/2023GRALY076.
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Cette thèse s’inscrit dans le cadre d’une collaboration entre le CEA et ORANO Mining avec pour objectif de développer une nouvelle sonde diagraphique basée sur l’interrogation neutronique active, dans le cadre de l’exploration et de l’exploitation de l’uranium dont une part importante de la production provient aujourd’hui de mines utilisant la lixiviation in situ. L’extraction chimique du minerai s’effectue directement dans le sol, sur plusieurs centaines de mètres, par injection et collection de solutions chimiques. Pour évaluer la rentabilité du puits, il est non seulement nécessaire de connaitre la quantité d’uranium disponible, mais aussi la perméabilité du milieu géologique. Cette dernière est déterminée en mesurant la « porosité hydrogène », à savoir la fraction volumique de la roche occupée par de l’eau, à l’aide de sondes qui émettent puis mesurent des neutrons ayant diffusé sur les noyaux d’hydrogène. L’uranium, et plus précisément son isotope 235, est aussi mesurable à l’aide de sondes équipées d’un générateur de neutrons pulsé. Ces travaux de recherche ont abouti à la conception d’une sonde permettant de réaliser ces deux mesures avec un unique compteur proportionnel à hélium 3 entouré de polyéthylène et blindé avec du cadmium. Des impulsions de neutrons de durée 50 µs sont émises par le générateur toutes les 5 ms (à 200 Hz). Puis, au cours des 800 µs qui suivent l’arrêt de chaque tir, on mesure les neutrons diffusés dans la formation qui ne sont pas thermalisés entièrement et peuvent encore franchir le blindage en cadmium. On obtient un comptage inversement proportionnel à la quantité d’hydrogène présente dans l’environnement. Sur les millisecondes qui suivent, les neutrons thermiques encore présents dans la roche font fissionner des noyaux d’235U, ce qui émet en moyenne 2.5 neutrons prompts par fission. Une partie de ces derniers sont mesurés par le bloc de détection, tandis que les neutrons du générateur, devenus thermiques 800 µs après l’arrêt du tir, ne peuvent plus franchir le blindage en cadmium. Grace à cette double discrimination, temporelle et énergétique, on peut mesurer le signal des neutrons prompts de fission qui est proportionnel à la concentration en uranium. Le flux de neutrons thermiques interrogateurs étant absorbé par l’hydrogène présent dans l’environnement, on utilise la porosité hydrogène mesurée pour corriger le signal des neutrons prompts de fission. Après avoir étudié par simulation Monte-Carlo les grandeurs affectant les performances de ces deux mesures (diamètre de forage, décentrage de la sonde, épaisseur et matériau de tubage, gangue de boue, lithologie), nous avons validé expérimentalement leur faisabilité en laboratoire. Tout d’abord, plusieurs chaines d’acquisition ont été testées pour pouvoir mesurer des taux de comptage instantanés de l’ordre de 106 s-1, pendant et juste après chaque tir du générateur de neutrons. D’autre part, une sonde maquette de laboratoire a été réalisée et testée dans un fût d’étalonnage rempli de 1.6 t de sable de Fontainebleau, spécialement conçu pour ces essais. Un bon accord entre l’expérience et les simulations a permis de valider la mesure de teneur en uranium et d’appréhender de nouveaux phénomènes, notamment l’activation de l’oxygène 17 responsable d’un bruit d’un fond actif significatif dans les formations siliceuses saturées en eau. La qualification des méthodes de calcul du signal et du bruit a été menée à bien, ce qui a permis d’estimer les performances prévues en situation réelle, notamment des limites de détection entre 10 et 200 ppm en 3 min de mesure pour des porosité hydrogènes respectives de 0 et 40%This PhD in the frame of CEA - ORANO Mining collaboration, aims to develop a new logging tool, based on neutron active interrogation, in the scope of uranium exploration and exploitation. A large amount of its production comes from In situ recovery mines, by leaching chemically the ore in the ground over hundreds of meters. It is mandatory to determine the amount of uranium available, but also the permeability of the sand, to evaluate the profitability. This geological quantity can be assessed from the measurement of the porosity hydrogen that is the volume fraction of water in the rock formation. It is possible to measure this one by using neutron probes. Uranium, and especially its 235 isotope, can also be measured with that kind of logging tools, if they rely on a pulsed neutron generator. This research leads to a new probe design that allows performing the both measurements with a unique cadmium-shielded-helium 3-proportional counter. The generator emits a 50 µs neutron burst every 5 ms (at 200 Hz). In the 800 µs after the salvo we can measure the not-fully-thermalised neutrons, thanks to the cadmium shield acting like a filter. The obtained count is inversely proportional to the hydrogen, and water, environment content. Over the following milliseconds, thermal neutrons of the rock formation will lead to 235U nuclei fissions, which emit in average 2.5 prompt fission neutrons. A chunk of these neutrons is emitted toward our counter, as the neutrons from the generator, fully thermalized after 800 µs, cannot cross the cadmium. Thanks to that double energy-time discrimination, it is possible to measure the prompt fission neutron signal contribution, which is proportional to the uranium concentration. As thermal neutrons are absorbed by the hydrogen content in the environment, we can use the porosity hydrogen measurement to correct the prompt fission neutrons signal from its effect. Furthermore, a parametric study has been conducting, using the Monte-Carlo simulation code MCNP 6.1, to compare the quantities that affect the measurements performances (e.g. diameter, standoff, casing thickness, casing, mudcake thickness, lithology). Finally, the new measurement methods feasibility has been validated through two experimental campaigns: in one hand, the capability of the electronics to handle input count rates in the 106 s-1 yield, during and right after a pulse of the neutron D-T generator. In the other hand, a laboratory model of the neutron probe has been built and tested in a dedicated calibration drum, filled with 1.6 t Fontainebleau sand. An agreement between experiment and computer simulations has been found, which validates the uranium concentration measurement and allows the understanding of the main components of the active background. This study highlighted the contribution of the oxygen 17 activation delayed neutrons, in the water saturated sandstone environments. The signal and noise analysis method were qualified, leading to the first estimations of in situ performances, like the detection limit of the uranium concentration measurement, from 10 to 200 ppm for 3 min of acquisition, for hydrogen porosities ranging respectively from 0 to 40%
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Lao, Hongbai. "Novel microporous organo-clay materials and organo-clay polymeric composite membranes." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6830.
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A series of quaternarized ammonium mono and di-cations, quaternarized amino acid ester mono and di-cations, and quaternarized polyammonium cations were synthesized by methylation reaction. The synthesized quaternarized ammonium derivatives were incorporated into the interlamellar space of the smectites, montmorillonite (SWy-1) and hectorite (SHCa-1). The adsorption of these quaternarized ammonium cations by the smectites were studied by colorimetric and Na-electrode methods. Also the CEC values were determined from the adsorption isotherms and were found to be close to the CECs of the smectites. The intercalation of the quaternarized ammonium cations into the interlamellar space of the smectites were evaluated by X-ray powder diffraction technique and the changes of the interlayer spacings upon intercalation were measured. The adsorption and X-ray results indicated that the quaternarized ammonium cations adopt a parallel orientation arrangement in the interlamellar space of the smectites. Insight into the micropore structure of the prepared organo-smectites has been obtained with N$\sb2$ adsorption and desorption studies. The BET interlayer surface area, external surface area, micropore volume and mesopore volume were calculated from the N$\sb2$ adsorption and desorption isotherms. The total BET surface areas of the organo-smectites were in the range of 58-224 m$\sp2$/g, depending on the size of the intercalated cations. It has been implied that the incorporation of the quaternarized ammonium cations into the interlamellar space of the smectites results in a microporous material with a network of cavities whose height and volume are controlled by the size and the shape of the organic cation. The gas chromatographic properties of these organo-smectites have been determined with focus on the separation of air, CH$\sb4$ and CO$\sb2$ as well as the separation of C$\sb1$-C$\sb4$ and C$\sb5$-C$\sb8$ hydrocarbons. The organo-smectites have been proven to be a GC adsorbent for gas separations. The separation of methane and carbon dioxide was controlled by the interactions with the clay surface, not by the interaction with the substituents of the alkylammonium chain. The shapes of the microcavities played a role in the separation of gas mixtures. The CO$\sb2$ retention time has been found to increase with increasing the free surface area of the organo-smectite. Moreover, it has been shown that the retention time of C$\sb1$-C$\sb4$ hydrocarbons decreased with increasing the free volume of the organo-smectite. Furthermore, some microporous organo-smectite materials have been imbedded into the cross-linked polydimethylsiloxane (PDMS) polymers giving composite membranes. The composite membranes have been evaluated by the gas permeation experiments. The pure gas permeation results showed that the gas permeabilities decreased upon filling of the organo-smectites into the PDMS polymers. The pure gas permeability ratios of O$\sb2$/N$\sb2$ and CO$\sb2$/CH$\sb4$ were found to be controlled by both the organo-smectite content and the microporosity of the organo-smectites. The maximum pure gas permeability ratio for CO$\sb2$/CH$\sb4$ achieved was 8.7 as compared to 3.9 which was obtained for organo-smectite free PDMS membranes.
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Probitts, E. J. "Organo-rhodium and organo-ruthenium chemistry : synthetic, structural and mechanistic studies." Thesis, University of York, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355522.
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Fisher, George Ayrton. "Synthetic and catalytic studies of organo and organo transition metal bismouth compounds." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357646.
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Martinelli, Marcia. "The synthesis and properties of some organo-ruthenium and organo-osmium clusters." Thesis, University of Cambridge, 1991. https://www.repository.cam.ac.uk/handle/1810/271906.
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Foreman, Mark Russell StJohn. "Organo-sulfur phosphorus chemistry." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/27934.
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P-organo-substituted dithiadiphosphetane disulfides have been prepared by the reaction of ferrocene and arenes with P4S10. Reaction of these compounds and Lawesson's reagent with alkenes, 2,3-dimethylbutadiene and other compounds gave organo-sulfur phosphorus compounds including 1,2-thiaphosphetane-2-sulfides such as P-ferrocenyl 1,2,5,5,7,8-hexamethyltricyclo[3,2,5,2,0]-3-thia-4-phospho-oct-7-ene-4-sulfide and a thiaphosphorine sulfide (P-ferrocenyl 4,5-dimethyl-3H,6H-1,2-thiaphosphinine-2-sulfide). Treatment of P-ferrocenyl thiaphosphorine sulfide with BuLi followed by carbon containing electrophiles (such as benzyl bromide or 2,4-dinitrochlorobenzene) gave ring-opened products. In addition treatment of dithiadiphosphetane disulfides with organic carbonyl compounds, including ketones, gave thiocarbonyl compounds. Platinum complexes were formed from the dithiadiphosphetane disulfides.
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Nieder, Anian. "Energetic organo-silicon compounds." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-162183.
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Campbell, Selina. "New organo-molybdenum complexes." Thesis, University of Cambridge, 1993. https://www.repository.cam.ac.uk/handle/1810/272559.
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Gloaguen, Bruno. "Synthèses en étoile de molécules activées par des greffons cationiques organo-fer et organo-cobalt." Bordeaux 1, 1991. http://www.theses.fr/1991BOR10605.
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L'activation d'aromatiques a ete realisee a l'aide de greffons cationiques cyclopentadienyles fer et cobalt. En une etape, de 6 a 12 liaisons carbone-carbone peuvent etre formees a l'aide de groupements fonctionnalisants. Les aspects synthetiques spectroscopiques et topologiques de ces precurseurs de fractals ont ete examines
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Fodil, Abdelkrim. "Ménages et logements dans la ville d'Oran : évolution et caractéristiques récentes." Paris 5, 1987. http://www.theses.fr/1987PA05H077.
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A Oran, comme dans toutes les villes algériennes, grandes ou moyennes, le problème de l'habitat constitue dans la phase sociale actuelle un sujet de préoccupation pour l'immense majorité des citoyens, tant il les concerne de façon dramatique et quotidienne. Ce travail s'interroge sur la problématique du déséquilibre démo-économique qui reste la caractéristique fondamentale des pays du tiers-monde. Ainsi, nous avons tenté de montrer le profond déficit de logement lie d'une part à une surutilisation, une dégradation et une mauvaise du parc immobilier, et d'autre part a une absence ou insuffisance d'une dynamique de l'offre en matière de logement. Le monopole d'état du parc immobilier, inspire d'une idéologie socialiste qui fut à l'évidence le contrôle absolu d'un secteur d'activité considéré comme hautement social, a eu pour résultat une alarmante pénurie qui, au-delà de la simple constatation de déséquilibre du marché de l'habitat, toucha profondément la vie quotidienne des citoyens. On constate que les retards des chiffres de l'offre par rapport à la demande ne pourront vraisemblablement à court et moyen terme être rattrapes sans un frein démographique. Et, contrairement à ce qu'il put sembler a certains, le manque de logement ne saurait être un facteur décisif de frein démographique.
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Beladis, Touria. "Algérie : la périphérie oranaise et ses difficultés d'intégration urbaine : étude centrée sur Pont Albin, Aïn Beïda, Bendaoud." Paris 1, 1997. http://www.theses.fr/1997PA010687.
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L'Algérie a herité d'un parc immobilier tres limité et vite epuisé. Effectivement juste quelques années apres l'indépendance, les villes, qui voient leurs populations autochtones augmentées par l'afflux des ruraux, n'offrent aucune possibilité d'intégration à ces nouveaux arrivants. De plus l'option politique du gouvernement Algérien de la politique de "l'industrie industrialisante" a fait considérer l'habitat comme un secteur social à la charge de l'opérateur public, mais qui n'était pas directement productif ; en conséquence il a été négligé au profit des pôles industriels de base. Ce n'est que vers la fin du 2eme plan quinquennal, face à la crise du logement et à l'urgence des besoins exprimés, que le pouvoir lance des projets de constructions de logements sociaux. Mais le rythme des réalisations demeure très lent, en dépit des techniques de préfabrication très mal adaptées à la societe Algérienne. Il faut tenir compte en plus des apports migratoires de plus en plus importants, et d'un accroissement national qui avoisine 3,2% par an en 1987. Les villes Algériennes ainsi s'étendent au delà de leur limite administrative pour pouvoir assimiler les populations en croissance. Oran est l'une de ces villes où le flux des populations et leur implantation à sa périphérie, s'effectuent généralement de façon illégale et anarchique. Les constructions sont souvent sommaires et s'inscrivent dans des espaces de mauvaise qualité. Malgré cela elles reviennent tres chers à cause des difficultés d'approvisionnement en matériaux de constructions que les promoteurs Algériens ont connues et de leurs prix élevés. L'existence de noyaux à habitat précaire, au sein de l'espace péri- urbain oranais, daté de l'époque coloniale. Actuellement cette périphérie connait une prolifération incontrolable d'agglomérations à habitat spontané et illicite, avec des mécanismes et des formes très variés et contrastés. Ces différents aspects sont développes tout au long de cette thèse quand on parle de la ville d'Oran et plus précisément de l'étude comparative du developpement sub-urbains des trois douars représentatifs de la périphérie oranaise qui sont : Bendaoud, Aïn Beïda et Pont AlbinAlgeria has inherited of a very limited stock of real estate which has been rapidly exhausted since. Indeed, just a few years after the country's independance, the cities which saw their native populations rise rapidly due to the arrival of rural inhabitants, no longer have any possibility of integrating new arrivals. What is more, the policy-option of the algerian government, baptised "the industrialising industry", considered lodging to be a social sector that the public powers should assume, but did not see it as directely productive. As a result, it was neglected in favour of the basic industrial poles. Only towards the end of the second 5-year plan, faced with a crisis in housing and the urgency of needs which the population expressed, did autorities launch projects to build social lodging. However, the rhythm of construction has been quite slow despite the use of techniques of prefabricated building which are poorly adapted to the algerian society. Moreover, the waves of migration continue, growing in amplitude, while growth rates of the population touched 3. 2% in 1987. Algerian cities have thus grown beyond their administrative limits in order to assimilate the increase in population. Oran is one of these cities where the flow of population and their implantation at its periphery usually takes place in a very chaotic and illegal manner. The buildings are often quite simple and inserted in spaces of low quality. Despite this, they are expensive due to problems in supplying building material which have affected algerian constructors and to high prices. The existence of centres of precarious lodging within the periurban space of oran dates back to the colonial era. Today, this periphery experiences and uncontrolled proliferation of spontaneous lodging with quite varied mechanisms and forms. These different aspects will be developped in the present thesis when dealing with the city of oran and more specifically in the comparative study of suburban development in the three douars which are representative of the oran periphery, i. E. Bendaoud, ain beida and pont albin
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Ech-Cherif, El-Kettani Sakina. "Les germènes : sources d'hétérocycles organo-matalliques." Phd thesis, Université Paul Sabatier - Toulouse III, 2005. http://tel.archives-ouvertes.fr/tel-00392024.
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Le travail développé dans ce mémoire est une contribution à l'étude de la réactivité de dérivés doublement liés du germanium. Nous avons réussi au cours de ce travail, d'une part à synthétiser le premier aminoester a-germanié cyclique stable ainsi que son homologue phosphoré; nous avons montré d'autre part à travers quelques exemples, que grâce à sa structure originale, le germène Mes2Ge=CR2 (Mes = 2,4,6-triméthylphényl, CR2 = fluorénylidène) peut se comporter, en fonction des nitriles qui lui sont confrontés, comme une base, un réactif dipolaire 1,2 ou un hétérodiène. Cette ambivalence démontre le riche potentiel du germène comme synthon. Ce germène est un composé hyperréactif: ainsi de nombreux hétérocycles de structure inédite - difficilement accessibles par d'autres voies - ont été obtenus par des réactions de cycloaddition [2+2] ou [2+3] entre ce dernier et divers substrats insaturés tels que les isocyanates et isothiocyanates, les nitroalkyles et le disulfure de carbone. Nos résultats montrent donc que ce dérivé à double liaison germanium-carbone constitue une "brique moléculaire" de choix en synthèse organométallique et hétérocyclique.
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Lux, Karin. "Organo-Phosphor-Chalkogenide und Elektronenreiche Phosphane." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-117246.
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Maj, Stanislaw Paul. "ESR studies of organo-halide radicals." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/33795.
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Exposure of a range of dilute solutions of halogenobenzenes in fluoro-trichloromethane to 60Co y-rays at 77 K gave the corresponding cations characterised by their ESR spectra. The approximate spin-densities on the halogens were greater than predicted by comparison with neutral x-bromo radicals and increased from ca, 8% for PhF+ to 23% for PhCl+, 30% for PhBr+ and 46% for PhI+ In accord with the fall in the ionization potential for this series of halogen. For PhBr+, replacement of para hydrogen by Br, OH and SH gave a steady fall in spin-density on Br reflecting increasing n delocallsation onto the para substituent. Evidence for dimer cation formation in concentrated solutions is presented. The major species obtained from benzyl chloride suggested a preferred conformation with the chlorine close to, but not in, the plane of the benzene ring, with a significant barrier for the in-plane site, in contrast with benzyl bromide with strong hyperfine coupling to bromine [Chapters 3, 4 and 9]. Exposure of dilute solutions of Me2C(Br)C(Br)Me2 In CD3OD and MeTHF to 60Co y-rays at 77 K gave the radical Me2CC(Br)Me2. From changes in the e.s.r. spectrum of this radical, it is deduced that the stable structure is asymmetric, but that the rate of migration of bromine between the two equivalent sites becomes fast on the e.s.r. time-scale at ca. 100-1 [Chapter 6]. Evidence is given for the 1,2-intramolecular proton shift in the interconversion of isobutyl to tert-butyl radicals. The parent material was dissolved in a variety of matrices and exposed to 60Co y-rays at 77 K. The reaction was observed using an in-cavity Proportional, Integral and Differential (PID) temperature control system [Chapter 5]. A single crystal of ethyl iodide was grown and irradiated at 77 K with a a 60Co y-ray source. The spectra were orientation dependent but it was not possible to determine the principal g-values and the elements of the hyperfine tensor [Chapter 7]. 1-Bromo adamantane was dissolved in a variety of deuterated matrices and exposed to 60Co y-rays at 77 K. No firm conclusions can be drawn regarding the single proton coupling of ca. 65 G to the bromine. Exposure of dilute solutions of m-dinitrobenzene or s-trinitrobenzene in methyltetrahydrofuran to 60Co y-rays at 77 K gave two species at 77 K. One, favoured at low doses, had features characteristic of mono-anions with the unpaired electron localized on one nitro-group. At high 7-ray doses a second species with triplet state characteristics grew at the expense of the first. The average separation between the two unpaired electrons was estimated to be 5-6 A.
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Gunawardena, Rohith. "Global distribution of organo-bromine gases /." Full text open access at:, 1989. http://content.ohsu.edu/u?/etd,245.
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Liddell, Michael John. "Studies in organo-transition metal chemistry /." Title page, contents and summary only, 1989. http://web4.library.adelaide.edu.au/theses/09PH/09phl712.pdf.
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Mažvilaitė, Inga. "Bendrovės organo sprendimų priėmimas ir negaliojimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2009~D_20110709_152328-76537.
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Lietuvos Respublikoje bendrovių veikla yra organizuojama pagal mišrią valdymo organų sistemą. Bendrovėse bet kokiu atveju visada veikia dalyvių susirinkimas ir bent vienas iš valdymo organų – bendrovės vadovas arba valdyba. Tuo tarpu priežiūros organas pagal Lietuvoje galiojančius teisės aktus – dispozityvus bendrovės organas, praktikoje sutinkamas gana retai. Bendrovių organai, vykdydami savo veiklą, priima sprendimus. Išanalizavus bendroves reglamentuojančių teisės aktų nuostatas bei Lietuvos Respublikos teismų sprendimus, darytina išvada, jog bendrovės organų priimti sprendimai bus laikomi teisėtais, jei: 1) nepažeis imperatyvių teisės aktuose ar bendrovės steigimo dokumentuose nurodytų normų, reglamentuojančių susirinkimo ar posėdžio sušaukimo iniciavimą, sušaukimą ir jo nutarimų priėmimą; bei 2) priimtas nutarimas nepažeis konkrečių asmenų teisių ar viešojo intereso. Civilinio kodekso 2.82 straipsnio ketvirtoji dalis numato pagrindus, kuriems esant juridinio asmens organų sprendimai teismo gali būti pripažinti negaliojančiais. Tokiais pagrindais laikomi: 1) sprendimo turinio prieštaravimas imperatyvioms įstatymo normoms; 2) sprendimo turinio prieštaravimas juridinio asmens steigimo dokumentams; 3) sprendimo turinio ar jo priėmimo procedūros prieštaravimas protingumo ar sąžiningumo principams; bei 4) kreditoriaus teisių ir interesų pažeidimas. Pažymėtina, jog priimtas sprendimas gali būti panaikintas tik tuo atveju, jei jo pasekmių negalima panaikinti jokiu kitu... [toliau žr. visą tekstą]Activity of the Companies is organized under mixed system of corporate governance in the Republic of Lithuania. In the Company in any case the General Meeting and at least one of the governing bodies - the Manager or the Board – are constituted. Meanwhile, the Supervisory Board under the existing laws is kept as an optional body of the company and is rather rare in practice. The bodies of the company, carrying out their activities, take various decisions. The analysis of provisions on company law and the decisions of the courts of the Republic of Lithuania showed that the decisions of the bodies shall be considered valid if: 1) they shall not violate the mandatory rules indicated in legal acts or company's founding documents, related to initiation and convening of the meeting and adoption of its decisions; 2) the decision shall not prejudice the rights of any person or the public interest. Article 2.82 of the Civil Code of the Republic of Lithuania provides bases under which the decisions of the bodies of the company may be invalidated under the court decisions, if they: 1) contravene the imperative provisions of the law; 2) contravene founding documents of a legal person; 3) contravene principles of reasonableness and good faith; and 4) violate rights and interests of the creditor. It should be noted that the decision may be revoked only if its consequences can not be removed at any other rational way. Such action in the court can be taken only by indicated subjects... [to full text]
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Kelland, Malcolm. "Organo-transition metal boron hydride chemistry." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258164.
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Hughes, Andrew K. "Studies in organo-transition metal chemistry." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276580.
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Atkinson, Peter J. "Characterisation of microemulsion-based organo-gels." Thesis, University of East Anglia, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292227.
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Wilson, Andrew. "Frontiers of organo- and hydridocalcium chemistry." Thesis, University of Bath, 2018. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.767564.
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In contrast to magnesium, investigations of the reactivity of well-defined and solvent-free heteroleptic calcium hydride species are somewhat limited. Chapter 2 describes an investigation into the synthesis and subsequent reactivity of a base-free β-diketiminatocalcium hydride species. An initial study indicated this solvent free species was more reactive than its THF solvated analogue, albeit via the same σ-bond metathesis and π-insertion pathways. The insertion chemistry of the C=C bonds of a range of n-alkenes into the Ca-H bond is described in Chapter 3. This reactivity has yielded the first isolated heteroleptic calcium n-alkyl species. The subsequent stochiometric and catalytic hydrogenation of these species is also reported. Chapter 4 reports that the unprecedented nucleophilic alkylation of benzene may be achieved with the highly nucleophilic calcium alkyls described in Chapter 3. Mechanistic and computational analysis suggests that the cleavage of the dimeric compounds to provide coordinatively unsaturated monomeric species is paramount. This chapter concludes with a study of the reactivity of the parent hydride with benzene and a variety of polyaromatic molecules and annulenes, to yield several species containing doubly reduced cyclooctatetradiene, naphthalene and anthracene fragments.
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Mkehlane, Moleko Samuel. "Electroanalysis of Organo-Chalcogenic Perovskite Nanomaterials." University of the Western Cape, 2017. http://hdl.handle.net/11394/6115.
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Magister Scientiae - MSc (Biotechnology)Organometallic halide perovskite solar cells have developed as one of the most promising contenders for the production of solar cells. The generic perovskite (PS) structure ABX3 allows manufacturing a broad range of PS materials by simple modification of building blocks A, B, and X (A = organic group, B = metal, and X = halide). The preparation of a series of solution-processed solar cells based on methylammonium (MA) lead halide derivatives, CH3NH3PbX3 (X=Cl, Br, and I) has been reported. These solar cells showed tunable optical properties depending on the nature and ratio of the halides employed. The photovoltaic performance of perovskite solar cells is dependent on the absorption of the light spectrum. The photovoltaic performance can be improved by widening the light absorption towards the near infrared spectrum. A panchromatric material that absorbs all the light from the ultra-visible to near infrared of the solar spectrum is an ideal photoactive layer. The optimal bandgap for single junction solar cells is known to be 1.1 and 1.4 eV. However, the bandgaps of methylammonium lead trihalide perovskites are beyond this range, and this inspired the realization of the lower bandgap perovskites.
2021-08-31
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Millett, Adam J. "Organo-iridium anticancer and antibacterial complexes." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/74076/.
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This thesis is concerned with the design of half-sandwich iridium(III) complexes of the type [(η5-Cp*)Ir(2-(Rˈ-phenyl)pyridine-R)X]0/+ (Cp* = pentamethylcyclopentadienyl), X = Cl- or pyridine derivatives) as anticancer agents, with particular focus on the effects that functionality in the chelating and monodentate ligands has on their chemical and biological properties. A set of phenyliminopyridyl (ImPy) complexes of the type [(η5-Cpx)Ir(ImPy)Cl]PF6 (Cpx = Cp*, tetramethyl(phenyl)-cyclopentadienyl (CpxPh) or tetramethyl(biphenyl)- cyclopentadienyl (CpxBiPh) was also synthesised and their solution chemistry and potential applications as antibacterial and anticancer agents investigated. Electron donating (-CH3, -OH, -CH2OH and –OCH3) or electron withdrawing (-F, -CF3 -CHO and –NO2) groups were introduced to various positions on the 2-PhPy ligand, giving rise to seventeen complexes [(η5-Cp*)Ir(2-(Rˈ- phenyl)pyridine-R)Cl]. Three X-ray crystal structures were determined, showing the expected pseudo-octahedral configuration. The functional groups have a profound effect on the resulting anticancer activities against a range of cell lines. Some complexes showed activity against A2780 human ovarian cancer cells comparable to cisplatin, and similar activity to [(η5-CpxPh)Ir(2-phenyl)pyridine)Cl]. The complexes all show similar extents of hydrolysis. The complexes preferentially bind to the model nucleobase 9-EtG over 9-MeA, and show the ability to catalytically oxidise the coenzyme NADH to NAD+. Contrasting anticancer activities were found for structural isomers. The hydrophobicity is related to substituent type and position on the ligand. The more hydrophobic complexes accumulated in A2780 cells to a greater extent. The extent of accumulation appeared to correlate with the potency of the complexes. The most potent complex [(η5-Cp*)Ir(2-(2ˈ-methylphenyl)pyridine)Cl] 13 (IC50 = 1.18 μM against A2780 cells) was modified via replacement of the chlorido monodentate ligand with pyridine derivatives (18 = pyridine (Py), 19 = 4- dimethylaminopyridine (Py-NMe2), 20 = 4-trifluoromethylpyridine (Py-CF3). The X-ray crystal structure was determined for 19. These pyridine complexes show less monodentate ligand release in aqueous solution and less binding to 9-EtG than parent complex 13. Complexes 13 and 19 show mild catalytic activity towards the oxidation of NADH to NAD+. Reactivity towards glutathione (GSH) decreased only in the case of 19 when compared with the parent complex 13. The reaction products include [(η5-Cp*)Ir(2-(2ˈ-methylphenyl)pyridine)(S-O)G] (sulfenate) and [(η5- Cp*)Ir(2-(2ˈ-methylphenyl)pyridine)(S-O2)G] (sulfinate) which are reliant on the presence of O2. The antiproliferative activity against A2780 cells increased upon enhancement of stability at the monodentate site (19 > 18 > 20 ~ 13) when activity was measured with no cell recovery time, with 19 exhibiting nanomolar activity (IC50 = 650 nM). All of the complexes induced high levels of total reactive oxygen species (ROS). Apoptotic cell death after 24 h recovery time was only observed for the pyridyl complexes. The ability to functionalise 2-PhPy complexes via Schiff base formation was examined using the aldehyde-containing complex [(η5-Cp*)Ir(2-phenyl-5- pyridinecarboxaldehyde)Cl] 6, and new conjugates were synthesised by conjugation to primary amines. Reactions with lysine-containing peptides were analysed by ultrahigh resolution mass spectrometry (UHR-MS) techniques which showed formation of new iridium-peptide conjugates via Schiff base formation with the free amino group of lysine. The imine bond in a complex bearing the fluorescent dansyl moiety (for fluorescence microscopy) was reduced using the hydride source Et3SiH, which appears to involve the metal centre through proposed formation of an Ir-H species. Eighteen [(η5-Cpx)Ir(ImPy)Cl]PF6 complexes with various ImPy ligands were synthesised and characterised, and six X-ray crystal structures were reported. They were found to exhibit more complex aqueous chemistry than the 2-PhPy complexes, but exhibit minimal hydrolysis at biologically-relevant concentrations of chloride, remaining predominantly as the chlorido species. The hydrophobicity of the complexes increased upon extension of the Cpx capping ligand: CpxBiPh > CpxPh > Cp*. The complexes show minimal activity against Gram-negative E. coli but CpxBiPh complexes show good activity (MIC = 8 – 15 μM) against Gram-positive S. aureus bacteria. The antibacterial activity is generally dependent on the hydrophobicity and extension of the Cpx capping ligand. Disruption of the bacterial cell membrane appears to be involved in the mechanism of action. The antiproliferative activity against A2780 cells follows the trend CpxBiPh > CpxPh > Cp*, where the complex [(η5-CpBiPh)Ir(ImPy-NMe2)Cl]PF6 31 exhibits an IC50 value against A2780 cells of 640 nM.
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Souza, Donizete de. "Estudos de fluorescencia em organo-gel." reponame:Repositório Institucional da UFSC, 1997. http://repositorio.ufsc.br/xmlui/handle/123456789/77292.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Fisicas e MatematicasMade available in DSpace on 2012-10-17T02:43:19Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-08T22:10:57Z : No. of bitstreams: 1 108505.pdf: 4374309 bytes, checksum: 42d56672e07bc8fcea4f4cd27ccd2f52 (MD5)
Um novo campo de estudo tem sido aberto com a solubilização de gelatina em microemulsão água em óleo. O sistema MBG é formado por Aerosol-OT, água e solvente orgânico, e este possui a vantagem de se obter géis hidrofóbicos transparentes com a viscosidade variando de líquido a verdadeiros géis consistentes. Este trabatho teve o objetivo de estudar a transição sol-gel através de medidas de fluorescência, tempo de vida e medidas de supressão, usando uma sonda hidrofóbica (pireno). Através da análise da intensidade de fluorescência das várias estruturas finas vibracionais (razão III/I) do monômero do pireno, é possível obter informações sobre o microambiente no qual ele se encontra. As medidas de fluorescência foram realizadas em sistemas de organo-gel de n-hexano, n-heptano e ciclo-hexano, com composições diferentes de água, surfactante e gelatina, tanto em sistema micelar líquido, como em gel homogêneo e transparente. Os resultados obtidos para a razão III/I em função e W0 (W0 = H2O/AOT) e percentagem de gelatina, mostraram uma mudança acentuada na transição sol-gel no sistema MBG. Nas medidas de supressão do pireno por brometo de N-etilpiridínio não foram observadas mudanças no espectro de fluorescência. Nas medidas de tempo de relaxação, observou-se que a sonda está localizada preferencialmente na fase orgânica para os sistemas de organo-gel de n-hexano e n-heptano, e que ocorre um particionamento maior em sistema de ciclo-hexano. Portanto, através destas técnicas, é possível estudar a transição sol-gel, além de obter novas informações sobre a sua microestrutura .
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Birepinte, Mélodie. "Amino(organo)boranes, synthèse et propriétés." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0231.
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Ce manuscrit présente la synthèse, la réactivité et les propriétés des amino(organo)boranes. Le diisopropylaminoborane a été utilisé dans le cadre de la formation de liaisons carbone-bore. La réactivité du diisopropylaminoborane en tant qu’agent de borylation a d’abord été mise à profit pour l’hydroboration des alcynes catalysée par le réactif de Schwartz. Une grande variété d’alcénylaminoboranes, -boronates et -diazaborolanes a ainsi été synthétisée. Leur transformation stéréosélective en bromoalcènes Z et E a également été optimisée. La borylation des alcynes vrais via un procédé tandem de déshydrogénation / couplage déshydrogénant a permis l’accès à une grande variété d’alcynylaminoboranes. Enfin, les différentes réactivités des aminoboranes ont été mises à profit dans la préparation d’acides boriniques comportant une fonction phosphine, ainsi que d’ une nouvelle classe de dérivés du bore chiraux par atropoisomérie autour de la liaison C-B. Ces aminoarylboranes chiraux ont été caractérisés par séparation des énantiomères complétée d’études spectroscopiques et de racémisationThis manuscript presents the synthesis, reactivity and properties of amino(organo)boranes. The diisopropylaminoborane has been used for the formation of carbon-boron bonds. Its reactivity as a borylating agent was first explored for the hydroboration of alkynes catalyzed by Schwartz reageant. A large variety of alkenylaminoboranes, -boronates and -diazaborolanes was thus synthesized. Their stereoselective transformation into E and Z bromoalkenes was also optimized. The borylation of terminal alkynes via a tandem process of dehydrogenation/ dehydrogenative coupling allowed the access to a large scope of alkynylaminoboranes. Finally, the different reactivities of aminoboranes were used for the preparation of borinic acids bearing a phosphine group but also of a new class of chiral boron derivatives via a C-B atropisomerism. These chiral aminoarylboranes were fully characterized after separating the enantiomers and running spectroscopic analyses and racemization studies
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Drury, Christopher John. "Nucleophilic substitution and cyclisation reactions of some polyfluoro-heteroaromatic and polyfluoroaromatic compounds." Thesis, Durham University, 1994. http://etheses.dur.ac.uk/5845/.
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This thesis describes the reactions of some highly fluorinated aromatic and heteroaromatic compounds, in particular derivatives of naphthalene, quinoline and isoquinoline. Chapter 1 provides a general introduction to the preparation, reactions and applications of fluorine containing organic materials. Chapter 2 describes the reactions of some quinoline- and isoquinoline- thiolates with dimethyl acetylenedicarboxylate in an attempt to form six membered heterocycles. Chapter 3 describes nucleophilic substitution reactions of heptafluoro- quinoline and -isoquinoline with sulphur and oxygen nucleophiles. The sulphur nucleophiles are found to attack the 6- site in the isoquinoline and the 4- site in the quinoline. The oxygen nucleophiles attack the 1- site in the isoquinoline and 2- and 4- sites in the quinoline. Chapter 4 describes competition experiments of heptafluoro-quinoline and -isoquinoline with nucleophiles. Relative rates of attack at the 1- position and 6- position in the isoquinoline are determined for a variety of nucleophiles. The relative rates of two nucleophiles are determined for 4- attack in the quinoline. The relative reactivities of the two heterocycles are determined for two different nucleophiles. Chapter 5 describes the pyrolysis of heptafluoro-2-naphtiiyl propynoate which yield two difluoro-butenone derivatives. These decarbonylate under further pyrolysis to yield a 1,1-difluorocyclopropene. All the products were identified by X-ray crystallography. Chapter 6 gives experimental details for Chapter 2 to Chapter 5.
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CANNIZZARO, DIEGO. "La musica per organo e clavicembalo nei regni di Napoli e di Sicilia tra XVI e XVII secolo." Doctoral thesis, La Sapienza, 2005. http://hdl.handle.net/11573/917444.
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Bendjelid, Abed. "L'organisation urbaine des bassins intérieurs oranais (Algérie) : formation et fonctionnement d'un réseau urbain dans un pays à économie planifiée." Paris 1, 1990. http://www.theses.fr/1990PA010507.
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Analyse de l'urbanisation d'un espace intérieur de l'Algérie; celle-ci s'inscrit dans le processus général de la poussée urbaine que connait le pays. Dans l'expérience algérienne de développement, l’état est l'agent principal de l'urbanisation. La première partie présente les principales caractéristiques de l'organisation urbaine actuelle des bassins intérieurs oranais, formée par un ensemble de petites et moyennes villes. Quant à la seconde partie, elle étudie les transformations des activités et de l'emploi et révèle les nouvelles formes de migrations connues par l'espace. La dernière partie enfin, est consacrée à l'approche des stratégies territoriales et à la dynamique des espaces. Enjeux et conflits entre les acteurs publics et privés se matérialisent clairement dans les pratiques spatiales. Est abordée en conclusion, la réorganisation générale de l'espace des bassins après une vingtaine d'années de planification nationaleThis is an analysis of town planning in an inland area of Algeria; which is noted in the general process of urban growth found in the country. In the algerian development situation, the state in the main agent in town planning. The first part out lines the important characteristincs of present urban organization in the inland plains of the Oran region, a combination of small and medium sized townships; while the second part studies the principal changes concerning activities and employment, showing the new spatial migratory patterns experienced. Next, the last section is devoted to approach of territorial strategies and spatial drives. Conflicting interests between state and private participants are clearly brought out in the spatial tactics. Finally, the conclusion considers the general reorganization in the region after twenty years of national planning
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Issad, Faïza. "L'abandon scolaire féminin dans le second degré : le cas de la ville d'Oran." Paris 5, 1987. http://www.theses.fr/1987PA05H099.
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L’éducation féminine semble être un domaine d'étude prioritaire et privilégié pour l'analyse et la connaissance du degré de développement d'un pays. En Algérie, l'éducation féminine est un domaine de recherche relativement nouveau, dont on reconnait de plus en plus l'importance. De ce point de vue, analyser le phénomène de la scolarisation féminine renvoie à l'étude du déroulement de la scolarité des filles, de leur réussite ou de leur échec (puisqu'il n'existe aucune discrimination entre les deux sexes quant à l'accès à l'enseignement), des causes de l'abandon scolaire, qui reste la caractéristique principale du système éducatif des pays en voie de développement. L'intérêt de cette recherche est, d'une part, de mettre en évidence les inégalités scolaires dues au système éducatif, d'autre part, de faire apparaitre l'impact du milieu socio-culturel et économique particulier à chaque fille sur ses chances de poursuivre une scolarité régulière, à travers l'analyse du phénomène de l'abandon scolaire féminin dans une ville urbaine algérienne, soit Oran dans notre étude. Le choix du thème a été dicte par les nombreux problèmes inhérents a la vie de la jeune fille. Son statut social et son rôle dans une société partiellement traditionnelle, sont un élément d'appréhension important de l'abandon scolaire féminin.
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Guessab, Slimane. "L'importance et la signification de l'absentéisme chez les ouvriers algériens : le cas de l'entreprise nationale de sidérurgie d'Oran." Bordeaux 2, 1986. http://www.theses.fr/1986BOR21005.
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Le présent travail voue une attention spéciale aux principales causes qui sont à l'origine de l'absentéisme des ouvriers algériens. Notre choix s'est porte sur les ouvriers de l'unité sidérurgique d'Oran et ceci au regard du modèle des comportements industriels très important qu'ils constituent. Tout d'abord, il conviendrait de signaler que l'objet de ce travail se voudrait une contribution à l'ensemble des réflexions et recherches qui visent à mettre en relief l'importance et la signification de l'absentéisme chez les ouvriers de l'industrie. Notre objectif ici n'est pas l'étude la plus systématique possible de l'absentéisme mais l'élaboration d'une interrogation méthodique qui nous permettra de rechercher les facteurs principaux qui expliquent l'absentéisme. Nous nous réserverons d'évoquer quelques facteurs qui posent des problèmes particulièrement intéressants. Notre ambition première donc est de mettre en valeur un processus et d'examiner les conditions de son émergence. Le danger le plus grave réside dans les limites théoriques inhérentes à ce travail : notre recherche est plus orientée vers une "sociologie concrète" pour pouvoir comprendre la signification et l'importance de l'absentéisme dans l'industrie algérienne, phénomène qui a pour conséquence de perturber la gestion du personnel au lieu de travail et de majorer le coût de la production. Il n'est pas dans notre projet d'étudier en termes généraux le phénomène d'absentéisme; la problématique de l'absentéisme possède des spécificités propres à chaque formation économique et sociale. Cette ambition de généralisation, quoique certainement fort intéressante, dépasse largement le cadre de notre étude. Le développement industriel a les caractéristiques propres à chaque pays, à son contexte politique, social et économique et l'expérience algérienne possède certaines spécificités qui méritent d'être soulignées.
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Gilles, Maren. "Sorptionsverhalten organo-mineralischer Bodenbestandteile gegenüber umweltrelevanten Radionukliden." [S.l. : s.n.], 1998. http://deposit.ddb.de/cgi-bin/dokserv?idn=956297064.
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Frazier, Joy Faith. "Organo-iridium compounds : synthesis, characterization and reactivity /." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08222009-040309/.
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Comina, Paul John. "New methodology in organo-chromium/-silicon chemistry." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320585.
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Williamson, Craig. "Imidazolylidenes in N-heterocyclic carbene organo-catalysis." Thesis, University of Aberdeen, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440601.
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A library of chiral and achiral imidazolium salts was prepared, and evaluated as potential pre-catalysts of the benzoin condensation. It was found that although the carbenes derived from these compounds possess catalytic activity, this was not as pronounced as that observed for alternative heterocycle classes. Asymmetric induction, although observed from imidazolylidenes for the first time in this work, is not of an order that could be considered useful, as has been seen for other NHC catalysts. This is attributed to the use of harsh reaction conditions, required to promote catalytic activity in this system. Two modifications were thus made to the imidazolium salt pre-catalysts in an attempt to make the reaction conditions less extreme. Imidazolium carboxylates were found to be suitable pre-catalysts, thus allowing the reaction to be performed under neutral conditions. Purinium salts were also investigated, based on the theory that these more electron deficient fused heterocycles would allow access to carbenes under milder conditions. Although problems were encountered in the synthesis of these salts, one example was prepared, however the available data indicate this exists as the incorrect regioisomer. Two strategies for catalyst immobilisation have also been investigated. It was found that polymer supported imidazolylidenes are capable of catalysing the benzoin condensation of a range of aromatic aldehydes, under a range of conditions, and can undergo a limited number of recycles. Imidazolium salts supported on silica were found to be unsuitable for the catalysis of this reaction. This was blamed on incompatibility of the persistently acidic matrix with the basic conditions required by the carbene. Application of imidazolylidenes to the intra-molecular Stetter reaction was also attempted, however this revealed NHC have the ability to act catalytically as bases. Further investigation of this observation suggested the effect is limited to α,β-unsaturated carbonyl compounds.
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Belt, S. T. "Intermediates and mechanisms in organo-rhodium photochemistry." Thesis, University of York, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234935.
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Lacey, I. N. "Antiwear behaviour of organo-phosphorous (III) ester." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37749.
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Mallik, Sanku. "Chemistry of enolates on organo-molybdenum complexes." Case Western Reserve University School of Graduate Studies / OhioLINK, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=case1059759899.
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Dhaher, S. M. "Sterically hindered organo-phosphorus and -tin compounds." Thesis, University of Sussex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374457.
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El-Kheli, M. N. A. "Sterically hindered organo-boron and -cadmium compounds." Thesis, University of Sussex, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356502.
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Rowley, Michael. "Some uses of tin compounds in organic synthesis." Thesis, University of Cambridge, 1986. https://www.repository.cam.ac.uk/handle/1810/265341.
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The work described in the dissertation is concerned mainly with organo-tin chemistry. In the first part, I describe the investigation of the stereochemistry of intramolecular electrophilic attack on a tin-carbon bond. The react ion of a number of cS - and � -s tanny 1 a lcoho 1 s and 0-stannyl acid chlorides was investigated, but stereochemical information was obtained only with the reaction of a 0-stannyl aldehyde to give a cyclopentanol, which proceeded largely with retention of configuration at the tin-bearing carbon, unlike the reaction of cS -stannyl alcohols, which give cyclopropanes with inversion. The second piece of work is a regio- and stereo-specific synthesis of allyl stannanes. s-stannyl ester enolates were treated with aldehydes to give alcol products with fairly good stereoselectivity: (~) and (~) enolates gave major products with different aldol relative stereochemistry. These aldols could be converted to s - hydroxy acids, then treatment with d imethy 1 formamide dimethyl acetal gave allyl stannanes stereospecifically, where steric and reactivity effects allowed. Thirdly, an investigation of the reaction of a tin cuprate with allenes is described. The cuprate reacts with 1,1-dimethyl allene followed by aqueous work up to give an allyl stannane, or the intermediate copper species can be quenched with a number of different ele,ctrophiles to give further substituted allyl stannanes. Similarly, allene itself reacts to give either vinyl or allyl stannanes, depending on the conditions used. Unfortunately, the factors governing the regiochemistry of the reaction with allene are not yet fully understood, and mixtu r es of products often result. Finally, I describe efforts to perform a kinetic resolution of a racemic Grignard reagent in which the chiral centre is the meta 1-bear ing carbon. It was hoped that react ion of the Gr ignard with half an equivalent of an optically active carbonyl compound would leave the remaining Gr ignard partially reso 1 ved. However, this did not prove to be successful.
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Jones, Craig Warren. "Nucleophilic aromatic substitution using supported copper(I) reagents." Thesis, University of York, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236184.
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Bell, Michael Niall. "Organometallic platinum group metal complexes incorporating macrocyclic ligands." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/13895.
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Conole, Grainne. "Structural studies of polynuclear metal carbonyl derivatives." Thesis, London Metropolitan University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290436.
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Guy, Franck. "Variabilité de l'appareil manducateur chez les hominoidea (mammalia, primates) actuels." Poitiers, 2001. http://www.theses.fr/2001POIT2284.
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Bégaud, Caroline. "La troisieme republique francaise coloniale en algerie. Pour une histoire politique d'oran de 1930 a 1939." Paris 8, 1999. http://www.theses.fr/1999PA081616.
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L'objet de cette these est l'histoire politique d'oran, chef lieu de departement francais en algerie coloniale, entre 1930-1939. La france ayant exporte son modele republicain outre-mer, nous retrouvons a oran, ville de 200 000 habitants, les memes partis, elections, institutions qu'en metropole, avec la singularite coloniale que seuls les europeens et les juifs naturalises font partie du corps citoyen. Au debut de notre periode, nous analysons que la lutte electorale s'etablit autour du discours antijuif, exalte par le mythe latin construit par les colonisateurs. L'arrivee en mai 1934 d'un personnage charismatique comme l'abbe gabriel lambert, elu maire sans etiquette et sans capital politique, bouscule les references partisanes en forcant les oppositions a elaborer des programmes plus stimulants. L'epoque de la formation des fronts (populaire, national, paysan) se clot par la victoire du candidat socialiste sfio aux legislatives de 1936. L'affrontement entre les deux camps est alors engage. D'une part, lambert prend la tete du rassemblement national, accueillant les nouveaux partis de droite comme le ppf ou le psf qui s'etablissent facilement dans le departement. D'autre part, les partis et les associations de gauche organisent une importante propagande pour recruter tant dans les milieux europeens qu'indigenes musulmans. Ces derniers sont de plus en plus sollicites pour adherer aux nouvelles formations ainsi qu'a leurs propres organisations, creees pour soutenir un projet d'emancipation politique. Dans cette situation de competition, nous avons teste la validite du concept d'affrontement politique << simule >> ou non. En effet, dans cette ville, dont la population d'origine iberique est majoritaire, non seulement la guerre civile espagnole se rejoue avec les mots, mais aussi les partisans politiques s'affrontent directement sur la conception de la souverainete francaise en colonie.
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Bendraoua, Fouzia. "Dynamique urbaine, instruments d'urbanisme et réalité terrain du groupement urbain d'Oran (Algérie) : création d'un SIG et imagerie spatiale." Marne-la-Vallée, 2005. http://www.theses.fr/2005MARN0274.
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Taddei, Fabio. "Rilevamento geologico della valle di Ortano, Elba orientale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2022.
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L'elaborato seguente è il prodotto di un lavoro di rilevamento geologico, svolto nella valle di Ortano, Elba orientale. Le osservazioni effettuate sul campo, riguardo le unità e le strutture che le caratterizzano, hanno portato ad un assetto geologico strutturale di una monoclinale con immersione verso Ovest, formata da embrici tettonici impilati l'uno sull'altro. Il movimento generale è top-to-east; in accordo all'assetto appenninico.
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Hamer, Julian C. E. "Organo-iron compounds on clays and pillared clays." Thesis, Sheffield Hallam University, 1998. http://shura.shu.ac.uk/19748/.
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(Ferrocenylmethyl)dimethylammonium chloride has been synthesised and the cation intercalated into the montmorillonite Westone-L. Variable temperature Mossbauer spectroscopy indicated that the molecule had a similar Debye temperature in each environment (144 +/- 5 K and 140 +/- 5 K respectively). The intercalated Mossbauer spectra revealed a Karayagin effect above 80 K. The cation occupies 80 % of the total exchange capacity of the clay, most likely orientated with the cyclopentadienyl rings perpendicular to the silicate layers. Thermal decomposition of the intercalate involved the volatilisation of iron containing fragments below 350°C. Variable-temperature XRD showed the intercalated sample had a d[001]-spacing of 1.55 nm at room temperature, which decreased at 200°C to give a d[001]-spacing of 1.3 nm. An iron oxide probably remains within the interlayer after the inserted molecule has decomposed. 2,2''-bis [(dimethylamino)methyl]biferrocene has been synthesised and intercalated into acid exchanged Westone-L. Variable temperature Mossbauer spectroscopy revealed a Debye temperature of 172 +/- 5 K which dropped to 150 +/- 5 K on intercalation. The molecule was shown to occupy 75 % of the total CEC of the clay and most likely resides with the cyclopentadienyl rings perpendicular to the silicate sheet. Thermal decomposition of the biferrocene intercalate indicated the loss of iron containing fragments below 430°C. Variable-temperature XRD indicated a d[001]-spacing of 1.65 nm at room temperature which collapsed to 1.41 nm at 250°C, after which it slowly decreased to 1.29 nm at 400°C. An iron oxide was probably left within the interlayer after the intercalated molecule had decomposed. Contact of the biferrocene with the acid Westone-L for 3 and 48 hours resulted in 2 and 11 % oxidation to biferrocenium respectively. Contact of iodine with a suspension of the intercalated biferrocene resulted in ca. 16 % oxidation to biferrocene. The biferrocenium intercalate exhibited "domain" type valence electron de-trapping above 200 K until by 250 K only a single charge averaged doublet was observed. The molecule N,N-dimethylaminomethylferrocene was successfully intercalated into aluminium pillared Westone-L, occupying 30 % of the total CEC of the original clay. The inserted molecule was found to have a Debye temperature of 113 +/- 5 K as determined by variable temperature Mossbauer spectroscopy. Decomposition of the inserted molecule involved the loss of iron containing fragments below 350°C. When heated in air the inserted molecule gave rise to high spin iron(IH) in a distorted octahedral environment. Heating the sample in nitrogen and hydrogen resulted in a species characteristic of high spin octahedrally co-ordinated iron(II). At the higher temperatures, the sample heated in hydrogen exhibited a further high spin octahedrally co-ordinated iron(K) species, with a less symmetric co-ordination sphere than the first.
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Needham, Russell James. "Organo-osmium anticancer complexes with novel azo-ligands." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/88273/.
Full textAbstract:
Piano-stool iodido Os(II) arene complexes containing AZPY (phenylazopyridine) π-acceptor bidentate ligands have been previously shown to exhibit potent anticancer activity and mechanisms of action that involve ROS generation, and differ greatly from early Os(II) arene complexes baring σ-donor bidentate ligands. The aim of this thesis was to explore Os(II) complexes containing other types of azo-ligands as well as continue our studies into AZPY complexes. Develop methods for improving the solubility of complexes, explore their intracellular activation, and further understand the mechanisms in which ROS levels are elevated inside cells. Firstly I explored Os(II) arene complexes with AZBTZ (phenylazobenzothiazole) bidentate liagnds. It was found that AZBTZ ligands can undergo unaided cyclometallation with Os(II) to form N,C-coordinated osmacycles as well as N,N-coordination. The amount of cyclo-metallation taking place seemed to be dependent on steric factors and occurred more for iodido complexes than chlorido and bromido analogues. The osmacycles were more stable than N,N-coordinated species and exhibited unique properties such as regio-specific deuteration of the aniline ring, but were too hydrophobic for biological evaluation. A total of 31 new Os(II) arene AZPY complexes were synthesised using the previously determined structure-activity relationships as a basis. The majority contained alkoxy and glycolic side chain substituents on the AZPY ligand, which was achieved via a novel synthesis protocol. Their trends in anti-cancer activity, solubility, lipophilicity and cell uptake were explored. It was found that varying the anion was the best method for improving aqueous solubility without affecting activity, lipophilicity or uptake. Key complexes were found to be very active against OE19 oesophageal cancer cells, were capable of inducing apoptosis and elevating ROS levels in A2780 cells, as well as causing cell cycle arrest in different phases of the cell cycle. Complexes [Os(ɳ6-p-cym)(5-EtO-AZPY)I]+ and [Os(ɳ6-p-cym)(AZPY-NMe2)I]+ were labelled with radioisotope 131I (β-/γ emitter, t½ 8.02 d) in Kings College London. They were relatively stable in human blood serum and cell culture medium over 24 h. However, in the presence of MCF-7 cells, rapid dissociation of the iodide monodentate ligand was observed in the supernatants. Cell uptake studies revealed a spike in 131I uptake after 5-10 min, which proceeds to steadily decline. The complexes seemed to undergo intracellular activation involving dissociation of the iodide ligand, and uptake of the complex is in competition with a rapid rate of iodide efflux, probably involving chloride transport channels. The aqua species, [Os(ɳ6-p-cym)(5-EtO-AZPY)H2O]2+, was synthesised and its pKa was determined as 4.55, meaning it exists predominantly as a +1 charged hydroxido species under physiological conditions. Using UV-Vis spectroscopy and EPR (DEPMPO spin trap), [Os(ɳ6-p-cym)(5-EtO-AZPY)OH]+, and its chlorido and iodido analogues were found to catabolise H2O2, generating HO· radicals in the process that were capable of cleaving lysozyme protein with effectiveness in the order OH > Cl > I. Interestingly it was discovered that iodide complexes are activated by iodide ligand dissociation in the presence of low concentrations of GSH (75 μM) to form the more active hydroxido species. However, in higher concentrations (7.5 mM), they formed Os-SG and Os-SOG adducts. Likewise, [Os(ɳ6-p-cym)(5-EtO-AZPY)OH]+ and its iodido analogue were both capable of oxidising NADH to NAD+ with effectiveness in the order OH > I. NADH was also capable of activating iodido species in a similar manner and generating the hydroxido species was required for NADH oxidation to proceed.
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Sartor, Valérie. "Synthèse de dendrimères polyallyles par voie organo-fer." Bordeaux 1, 1998. http://www.theses.fr/1998BOR10586.
Full textAbstract:
L'utilisation du greffon cpfe#+ dans l'activation d'aromatiques a permis la synthese d'un cur et d'un synthon dendritique polyfonctionnels, comportant respectivement 9 et 3 fonctions allyles. Deux strategies de synthese de dendrimeres polyallyles ont ete developpees : la strategie divergente et la strategie convergente. La premiere voie de synthese, divergente, a conduit a un dendrimere de premiere generation isomoleculaire comportant 27 groupements allyles peripheriques. L'iteration de la sequence reactionnelle a permis d'obtenir la seconde generation de faible polymolecularite possedant 81 fonctions ethyleniques en surface et d'atteindre le dendrimere de troisieme generation (243 branches). L'elaboration d'une deuxieme strategie de synthese des dendrimeres polyallyles, la strategie convergente, a conduit a la synthese de dendrons de premiere et seconde generation possedant respectivement 9 et 18 groupements fonctionnels allyles. La construction, par la voie convergente, du dendrimere polyallyle de seconde generation a ete realise par couplage de 3 equivalents de dendron de premiere generation avec un cur trifonctionnel.