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1

Bukarica, Marija, and marijab@unimelb edu au. "The technical expert assumes managerial responsibilities: an Interpretivist perspective on transition in Australia." RMIT University. Graduate School of Business, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091005.140123.

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In this study, Interpretivist epistemology and abductive research strategy were used to examine transcripts of sixteen two-hour focused interviews. The research sample was a group of technical experts who assumed managerial responsibilities within their organisations (transitional managers). The subjectively perceived experiences of the transition were examined as well as the respondents' intersubjective interpretations of the transition from the organisational perspective. The aim was to explore the perceived characteristics of the transitional experience. The main findings of this study could be summarised as follows: firstly, it was found that there were three main types of transitional managers: the unwilling, the pragmatic and the eager managers. Secondly, the key motivations to take the manager role for all three categories were higher remuneration, technical peer respect and the respondent's new role as an organisational decision-maker. The third finding of this study was that there were two types of transitions, the complete transition which the majority of the eager managers went through and the technical transition which was experienced by the unwilling and the pragmatic managers. Related to that finding was the link between the type of organisation, its culture and the leadership skills required in that organisation. The fourth finding was that, irrespective of the amount of time in the manager role (six months to eleven years) or the type of transition (complete or technical), all respondents in this study continued to identify themselves as technical experts with the respondents who underwent a complete transition also seeing themselves as managers. Related to this finding was the respondents' continued identification as technical experts being largely due to their need to identify with their peers (other technical experts). The fifth major finding of this study related to a lack of career planning by the respondents and little or no succession and management development planning by the respondents' organisations. In a contribution to the theory of leadership studies, this study examined leadership as a social process, building on the existing leadership concepts and theories and putting them in a social context of subjective efforts by the researcher to interpret the respondents' transitional experiences through typification of the leadership characteristics into seven themes. The need to apply an individual contextualisation was seen as essential to understanding the transitional managers' response to their own transition. In doing so, the study has contributed towards narrowing the existing empirical literature gap on the transition processes. The contributions of this study need to be seen in the context that explorative research such as the one carried out here is not considered generalisable, as its aim was to explore and describe particular phenomena. Nevertheless, insights from this study were eight
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2

Göransson, (Asker) Christian. "First-Principles calculations of Core-Level shifts in random metallic alloys: The Transition State Approach." Thesis, Linköping University, Department of Physics, Chemistry and Biology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2581.

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The overall aim of this thesis is to compare different methods for calculation of Core-Level shifts in metallic alloys. The methods compared are the Initial State model, the Complete screening and the Transition state model. Core-level shifts can give information of chemical bonding and about the electronic structure in solids.

The basic theory used is the so-called Density-Functional-Theory, in conjunction with the Local-Density Approximation and the Coherent-Potential- Approximation. The metallic alloys used are Silver-Palladium, Copper-Palladium, Copper-Gold and Copper-Platinum, all inface-centered-cubic configuration.

The complete screening- and the transition-state model are found to be in better agreement with experimental results than those calculated with the initial state model. This is mainly due to the fact that the two former models includes final-state effects, whereas the last one do not. The screening parameters within the Coherent-Potential approximation are also investigated. It is found that the Screened-Impurity Model can extend the validity of the Coherent-Potential-Approximation and increase it's accuracy.

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3

Bennet, A. J. "A study of the complete kie description of the transition state for the specific acid catalysed hydrolosis of methyl alpha- and beta-glucopyranosides." Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354681.

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4

Atallah, Tarek. "Measuring the Transition toward Less Energy Intensive Economies : modeling Solutions for the Demand-Side." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLED024.

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Le monde est actuellement confronté à une transition du marché de l'énergie qui est influencée notamment par la dynamique de la croissance économique globale, les négociations relatives aux changements climatiques et des prix de plus en plus volatils. Cette évolution rapide des réglementations et de la macro-économie transformera les conditions de la demande d'énergie, obligeant les gouvernements à acquérir un ensemble croissant d'outils quantitatifs pour mieux évaluer les résultats de leurs politiques fiscales. Cette thèse aborde cette problématique en analysant, par une approche basée sur les élasticités, les différentes facettes de la demande d'énergie dans le but d'achever une consommation énergétique durable. Cette approche est complémentée par l'analyse par grappes, la décomposition structurelle ainsi que par diverses outils économétriques appliques conjointement à l'échelle mondiale et nationale. Une attention particulière est faite sur la modélisation de la demande des marchés subsidiés notamment des pays du Conseil de Coopération du Golfe Arabique
The world is currently witnessing a transition in the energy scene that is significantly characterized by global economic growth dynamics, climate change negotiations and volatile energy prices. Rapidly evolving regulatory and macro-economic environments heavily impact on the demand-side of energy, forcing governments to acquire an ever-increasing set of quantitative tools to better assess the results of their taxation policies.This thesis addresses some of these issues by analyzing various facets of energy demand in order to generate sensible demand and price elasticities with real-life applications in sustainable energy management. For that purpose, a combination of cluster, decomposition and multiple econometric analysis is undertaken at global, regional and country-specific levels for households complemented by a policy analysis. A special focus is made on modeling consumer demand behavior for resource-rich economies of the Gulf Cooperation Countries, and the potential impact of removing residential electricity subsidies on the net societal welfare of Saudi Arabia
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5

Nuel, Didier. "Etude de la reactivite de fragments alkylidynes dans des clusters trinucleaires du fer." Toulouse 3, 1986. http://www.theses.fr/1986TOU30206.

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Reactivite des complexes fe::(3)(co)::(9)(cch::(3))(coc::(2)h::(5)) ou fe::(3)(co)::(10)(cch::(3))(h). Les reactions de couplage des groupes alkylidynes avec les algues sont faciles. L'action de co a mis en evidence le couplage reversible dans des conditions douces de 2 fragments alkylidynes. En general, la presence du coordinat hydruro rend les reactions plus complexes
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6

Gourdon, André. "Synthèse et étude structurale de clusters de fer contenant un hétéroatome du type carbure, nitrure, phosphure." Paris 6, 1986. http://www.theses.fr/1986PA066404.

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7

Rahmouni, Noureddine. "Synthese et reactivite de complexes dinucleaires des metaux de transition." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13080.

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Synthese de complexes dinucleaires de cu(ii)-dppm, presentant des proprietes magnetiques interessantes et de cu(i)-dppm dont on etudie la structure. Etude particuliere de rh::(2)(dppm)(co)**(2+) et rh(dppm)::(2)(co)::(2)(mu -co)**(2+). Grande reactivite de ce dernier, notamment avec un alcyne terminal phcch dans lequel une activation c-h a lieu pour conduire a un complexe mu -eta -acetylene
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8

Navarre, Didier. "Carbonylation des complexes μ-alkylideniques." Paris 6, 1986. http://www.theses.fr/1986PA066101.

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Synthèse et carbonylation des complexes μ-alkylidene, en particulier fe-μ-méthylène. Mise en évidence de la réaction de dicarboxylation correspondant à l'insertion d'une molécule de Co dans chaque liaison du C en pont. Le premier intermédiaire est un complexe acyl.
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9

Marzak, Saïd. "Complexes du cuivre (i) construits sur le fragment (ms::(4))**(2-) (m=mo,w) : role du ligand thiocyanate dans l'edification de composes heterometalliques a structure infinie." Paris 6, 1988. http://www.theses.fr/1988PA066401.

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Preparation de complexes du type (nr::(4))::(n)(cu::(4)(ncs)::(4)ms::(4)), m=mo, w, r=me, et et n=2 ou 3. Selon la taille du cation, obtention de macrostructures bidimensionnelles ou tridimensionnelles; l'insertion du cation pph::(4)**(+) conduit a la formation d'une structure infinie de chaines lineaires
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10

Lugan, Noël. "Clusters du ruthenium a ligands assembleurs : stabilite, reactivite." Toulouse 3, 1987. http://www.theses.fr/1987TOU30156.

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Etude de la reactivite d'agregats derives de ru::(3)(co)::(12) stabilises par des coordinats polydentes phosphores et/ou azotes, en vue d'application en catalyse homogene. Les coordinats assembleurs sont appm et diphenylpyridylphosphine. On etudie egalement la reactivite des complexes a coordinats acyle ru::(3)(co)::(9)(c(o) (c::(6)h::(5))) (p(c::(6)h::(5)) (c::(5)h::(4)n))
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11

Delavaux, Béatrice. "Complexes heterobimetalliques hydrures (ru-m) (m=rh,ir,cu) a ligands bisdiphenylphosphinomethane : synthese et reactivite." Toulouse 3, 1986. http://www.theses.fr/1986TOU30078.

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Synthese de complexes hydruro a coordinat dppm : ph::(2) pch::(2) pph::(2). L'etude de la reactivite de certains complexes comme rurhh::(2)cl(cod) (dppm)::(2), conduit a la preparation de nouveaux hydrures dont on etudie les structures
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12

Henry, Marc. "Application du concept d'electronegativite aux processus d'hydrolyse et de condensation en chimie minerale." Paris 6, 1988. http://www.theses.fr/1988PA066293.

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Utilisation des procedes sol-gel pour elabour des materiaux a base d'oxydes et a proprietes optimisees. Mecanismes d'hydrolyse et de condensation des precurseurs moleculaires (alcoxydes ou sels metalliques) aboutissant a l'obtention de materiaux mixtes organiques/inorganiques
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13

Ries, Michel. "Synthese et reactivite de clusters heterometalliques contenant le ligand assembleur ph : :(2)pch::(2)pph::(2)." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13208.

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14

Jund, Rodolphe. "Electrochimie de clusters mixtes tetrametalliques." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13175.

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15

Labonnette, Daniel. "Etude des especes du vanadium iv en milieu faiblement acide et alcalin : isopolyanions mixtes mo**(vi)-v**(iv), complexes carbonates de v**(iv)." Orléans, 1987. http://www.theses.fr/1987ORLE2009.

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L'alcalinisation progressive d'une solution acide de vo**(2+) par une base forte, entraine la formation successive des especes : vooh**(+), (vooh)::(2)**(2+) vo(oh)::(2), v::(4)o::(9)h**(-), v::(4)o::(9)h**(-), v::(4)o::(9)**(2-), vo(oh)::(3)**(-) et des ions polycondenses en milieu fortement basique et tres concentre en v(iv). Quand l'alcalinisation est realisee par hco::(3)**(-) ou co::(3)**(2-), il y a formation de complexes carbonato
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16

Tahiri, Mohamed. "Phtalocyanines de fer(i) et de fer(0) : synthese, structure et reactivite." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13043.

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Synthese et caracterisation d'une serie de complexes monoreduits de phtalocyanine de fer de type (fe pc r::(8))**(-) ou r=och::(3), ch::(3), h, cl et cn. On donne les structures par rx de composes monoanioniques et dianionique fe pc**(-) et fe pc**(2-). Proprietes chimiques de fe pc**(2-). De tels especes peuvent etre des modeles d'intermediaires formes dans la reaction de la phenylhydrazine sur la metmyoglobine ou dans le metabolisme de substrats suicides par cytochrome p450
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17

BLUM, THIERRY. "Synthese et reactivite de complexes heterometalliques a ligand (s) phosphure (s)." Université Louis Pasteur (Strasbourg) (1971-2008), 1989. http://www.theses.fr/1989STR13078.

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18

Chambron, Jean-Claude. "Synthese et etude de complexes du cuivre (i) et du ruthenium (ii) en vue de la separation intramoleculaire des charges photoinduites." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13092.

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Preparation de 2 macrocycles contenant a la fois des sites chelatants diphenyl-2,9 phenanthroline-1,10 et dialkyl-4,4' ou diaryl-4,4' bipyridine-2,2'. Dans le complexe heterodinucleaire il existe une interaction a l'etat excite entre les 2 metaux
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19

Cartier, dit Moulin Christophe. "Structures fines d'absorption des rayons X de complexes moléculaires d'éléments de transition de la premiere période." Paris 11, 1988. http://www.theses.fr/1988PA112002.

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Ce travail est consacré à l'étude par spectroscopie d'absorption des rayons X de complexes moléculaires d'éléments de transition de la première période. Une première partie porte sur l'étude fondamentale des structures fines au seuil d'absorption : nous utilisons la flexibilité de la chimie de coordination pour étudier des complexes de stéréochimie et de structure électronique variées. Pour des molécules discrètes de structure connue, nous mettons en évidence l'influence sur le seuil du degré d'oxydation et de l'état de spin de l'élément de transition, de la symétrie du site, des distances métal-ligand et des différentes couches de voisins. Nous interprétons les transitions vers des états liés dans une approche orbitale moléculaire. Dans le domaine d'énergie où le photoélectron est éjecté, nous utilisons l'approche "diffusion multiple". L'intérêt et les limites des deux modèles sont discutés. Enfin, la présence de bandes d'intensité faible est attribuée à des transitions biélectroniques. La compréhension de l'influence des différents paramètres électroniques et structuraux qui déterminent les structures fines du seuil, et l'analyse EXAFS, sont ensuite utilisées pour l'étude structurale et stéréochimique de matériaux nouveaux intéressants pour leurs propriétés physiques, chimiques et catalytiques. Nous avons ainsi caractérisé :- les modifications structurales associées aux transitions de spin dans des complexes du fer(ll), du fer(lll) et du cobalt(ll). - la stéréochimie de complexes du titane(IV), actifs dans l'oxydation de sulfures en sulfoxydes : à toutes les étapes de la réaction, les espèces sont octaédriques et ne présentent pas d'arrangement di -oxo. - l'ordre local dans les porphyrines de fer à anse de panier, modèles de l'hémoglobine. Le spectre de la forme oxygénée permet de proposer une formulation Fe(ll)-02 plutôt que Fe(lll)-02 -. L'EXAFS résolu dans le temps permet de réaliser des cinétiques structurales et a été utilisé pour étudier l'environnement de l'ion fer au cours de la réaction d'oxydation d'une porphyrine de fer(ll) à anse de panier
Ln this work, molecular complexes of the first period transition elements are studied by X-ray absorption spectroscopy. The first point is devoted to a fundamental study of the absorption edge: we take advantage of the versatility of coordination chemistry, to study complexes, with different stereochemistries and electronic structures. Ln the case of isolated molecules with well-known structures, we point out the influence of oxidation and spin states of the metallic ion, symmetry, metal-ligand distances and remote neighbours shells upon the edge. We discuss the transitions towards bound states using a molecular orbital approach. As for the XANES part of the spectrum, we use multiple scattering theory. We discuss the interest and the limitations of the two models. Sorne weak bands can be attributed to bielectronic transitions. This knowledge of the influence of different structural and electronic parameters which impel the fine structures of the edge and EXAFS spectroscopy are then used to characterise the local structure and stereochemistry of new compounds, of interest for their physical, chemical and catalytic properties. Then we studied:- The structural changes occurring during thermal spin cross-over in iron(ll), iron(lll) and cobalt(ll) complexes. - The stereochemistry of titanium(IV) complexes active in oxidation of sulfides in sulfoxides :at each reaction step, species are octahedral and do not show di µ oxo geometry. - The local order in basket-handle iron porphyrins, model compounds of haemoglobin. The spectrum of the oxy species allows to propose a Fe(ll)-02 formulation rather than a Fe(lll)-02 -. We used the time resolved EXAFS spectrometer at LURE to record structural kinetics data and study iron surroundings during the oxidation of an iron(ll) basket-handle porphyrin
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20

Venter, Gerhard (Gerhard Abraham). "An Ab Initio density functional study of the structure and stability of transition metal ozone complexes." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52650.

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Thesis (MSc)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: A thorough search through the literature as well as through the Cambridge Crystallographic Structural Database resulted in no examples of a neutral ozone acting as ligand in a complex with any metal. Ionic compounds containing ozonide as anionic species, however, are well known throughout the literature and not surprisingly the only result for 0₃ and a metal in the CCSD was an ionic rubidium ozonide compound. What follows is a systematic study into the result of placing an ozone ligand within complexing distance of a transition metal (the first transition row from titanium to copper). Due to the novelty of the system, as first approximation four different orientations of the ozone ligand relative to the metal (a metal cation in these calculations) were investigated. It was found that coordination through the terminal oxygens resulted in energy minima for all the metal cations, although not necessarily the absolute energy minimum on the potential energy surface for the specific cation. A further structural study was done by adding carbonyl and hydrogen ligands to the system, according to the 18-electron rule. For these calculations coordination through the terminal oxygens was employed. In both series the dissociation energy was also calculated. The dissociation energies for the M(CO)nHm(0₃) complexes were all positive, indicating that they are theoretically stable structures. The resulting wave functions were then analysed with the help of three techniques: Atoms in Molecules (AIM), Charge Decomposition Analysis (CDA) and Natural Bond Orbital Analysis (NBO). AIM showed that bonds were indeed formed between the ozone ligand and the transition metal and hinted that the bonding model can be interpreted with the Dewar-Chatt-Duncanson (DCD) model of σ-donation and л-back donation. CDA confirmed that this was the case. NBO results proved erroneous due to the largely delocalized electronic structure of the complexes.
AFRIKAANSE OPSOMMING: 'n Deeglike soektog deur die literatuur en die Cambridge Crystallographic Structural Database het geen resultate gelewer van komplekse waarin 'n neutrale osoonligand komplekseer met 'n metaal nie. Ioniese verbindings waarin die osonied as anioon optree, is wel bekend deur die literatuur en die enigste resultaat in die CCSD - vir 'n soektog bevattende osoon en 'n metaal - het 'n rubidiumosonied-verbinding opgelewer. Wat volg is 'n stelselmatige studie om die effek te ondersoek indien 'n osoonligand naby genoeg aan 'n oorgangsmetaal geplaas word om kompleksering te bevoordeel (metale wat gebruik is, is die eerste oorgangsreeks vanaf titanium tot koper). As gevolg van die onbekendheid van die sisteem is vier verskillende oriëntasies van die osoonligand relatied tot die metal ('n metal katioon in die geval) as beginpunt ondersoek. Daar is gevind dat koordinasie deur die terminale suurstowwe van die osoonligand vir al die metal katione lei tot energie minima, alhoewel dié minima nie noodwendig die globale minima op die potensiële energie oppervlaktes van die katione is nie. 'n Verdere studie is gedoen deur karboniel- en waterstofligande tot die sisteem te voeg, gelei deur die 18-elektron reel. Vir hierdie berekeninge is koördinasie deur die terminale suurstowwe gebruik. In beide reeks is dissosiasie-energieë bereken. Die dissosiasie energieë van die M(CO)nHm(0₃) komplekse was deurgaan positief wat aandui dat die komplekse teoreties stabiel is. Die verkrygde golffunksies is hierna analiseer deur middel van drie tegnieke: Atoms in Molecules (AIM), Charge Decomposition Analysis (CDA) en Natural Bond Orbital Analysis (NBO). AIM het getoon dat bindings inderdaad gevorm word tussen die osoonligand en die metal en bet die moontlikheid laat ontstaan dat die bindingsmodel volgens die Dewar-Chatt-Duncason (DCD) model van σ-donasie en л-terugdonasie geïnterpreteer kan word. Hierdie waarneming is bevestig deur CDA. NBO resultate kon nie suksesvol gebruik word nie as gevolg van die hoë graad van electron delokalisasie van die komplekse.
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21

Gomes, de Lima Bernardes Miriam. "Réactivité de complexes organométalliques mono- et dinucléaires : synthèse de thiolato-composés du molybdène, du tungstène et du cobalt : étude de la formation de liaisons c-c dans la sphère de coordination du métal." Brest, 1986. http://www.theses.fr/1986BRES2008.

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Caracterisation des complexes ((c::(5)h::(5))(co)::(2) lwc(cf::(3)) = c(cf::(3))h) et (c::(5)h::(5))(co) lwc(o)c(cf::(3)) = c(cf::(3))h) (l=co,pr::(3),p(or)::(3)) synthese de complexes dinucleaires de mo et w. L'addition oxydante de dialkylsulfure a des derives biportes de mo(ii) et w(ii) a donne lieu a la formation de complexes thiolato triportes ((c::(5)h::(5))(co)m(mu -sr)::(3)m(co)(c::(5)h::(5)))tx**(-)
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22

Faulmann, Christophe. "Conducteurs derives de metaux de transition : complexes moleculaires, polymeres, oxydes de cuivre." Toulouse 3, 1988. http://www.theses.fr/1988TOU30160.

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Habtu, Michael M. "A study of the transport, extraction and co-ordination chemistry of a number of thiourea ligands with a series of transition and post-transition metal ions." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/97374.

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Thesis (MSc)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: In this study, a number of mono- and di-substituted acyl(aroyl)thioureas were investigated for potential application as specific carriers (ionophores) for the transport and extraction of Ag(l) from a mixture of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(lI) ions. The experimental arrangement for the transport experiments employed a liquid membrane set up involving a 3-phase system - 2 aqueous phases (source and receiving phase) separated by a chloroform membrane incorporating the ligand. Competitive metal ion transport experiments were conducted using the liquid membrane set up. The aqueous source and receiving phases were analyzed using Atomic Absorption Spectroscopy (AAS) and results were confirmed by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICPOES). The transport results show that the N,N-dialkyl-substituted-N'-acyl(aroyl) (HL) thioureas studied, with the exception of the N,N-di-(2-hydroxyethyl)-N'-benzoylthiourea (HL3 ) and N-piperidyl-N'-4-nitrobenzoylthiourea (HL9 ), were efficient and selective for Ag(I). HL9 was also selective for Ag(l) but not efficient. HL3 was selective for Cu(II). Under the experimental conditions employed, 13% Cu(lI) was transported by HL3 . Among the N,Ndialkyl- N'-aroylthioureas, maximum Ag(l) transport was obtained by using N,N-diethyl-N'-4- chlorobenzoylthiourea (HL5 ) and N,N-di-n-butyl-N'-benzoylthiourea (HL \ Under the experimental conditions employed, the percentages of Ag(l) transported by HL5 and HL 1 were 48% and 42% respectively. The transport selectivity and efficiency of 3,3,3' ,3'-tetraethyl-1 ,1'-isophthaloylbisthiourea (H2L12 ) and N,N-diethyl-N'-camphanoylthiourea (HL13)for Ag(l) were also studied. We were particularly interested, in comparing the Ag(l) transport and extraction efficiency of these ligands with that of the HL and H2L ligands. The experimental results reveal that, of all the ligands we investigated in this study, HL 13 was the most efficient and selective carrier for Ag(l) transport. The interesting result is that, depending on the ligand concentration used, HL 13 transported 71-81% of Ag(I). Competitive two-phase metal ion solvent extraction experiments were also performed under conditions similar to the transport studies. The results show that by varying the ligand concentration in the membrane phase, up to 100% Ag(l) can be selectively and efficiently extracted from the mixture of the seven metal ions. Finally, the N,N-di-(n)-butyl-N'-benzoylthiourea (HL1) ligand and its complex with Ag(l) were synthesized. Single crystals of the complex were grown for X-ray crystallography and the crystal and molecular structure of the complex was determined. The crystal structure showed that Ag(l) is bonded to the deprotonated ligand through the S,O atoms forming interesting cluster [Ag (L - S, 0)] 4 in the solid state. This structure is monoclinic and crystallizes in the space group P21!c with a = 17.805 (4) A, b = 21.759 (4) A, c = 36.438 (7) A, f3= 96.34(3)°, Z = 8 and a final R-factor of 5.4%.
AFRIKAANSE OPSOMMING: In hierdie proefskrif is 'n aantal mono- en di-gesubstitueerde asiel(ariel) tioureums ondersoek vir moontlike gebruik as ionofore (spesifieke draers) vir die transportasie en ekstraksie van Ag(l) vanuit 'n mengsel van Co(ll), Ni(II), Cu(II), Zn(II), Cd(II), Ag(l) en Pb(lI) ione. 'n Drie-fase selsisteem is gebruik vir die transportasie eksperimente, twee waterige fases (bron- en ontvang-fase) wat geskei is met die chloroform membraan fase wat die ligande bevat. Kompeterende metaalioon transportasie eksperimente is uitgevoer met behulp van hierdie vloeistof membraan stelsel. Die twee waterige fases is deur middel van Atoomabsorpsie Spektroskopie (AAS) ge-analiseer en resultate is bevestig met gebruik van Induktief-gekoppelde Plasma-Optiese Emissie Spektroskopie (IGP-OES). Die resultate het getoon dat elkeen van die N,N-dialkiel-gesubstitueerde-N'-asiel(ariel) (HL) tioureums, met uitsondering van N,N-di(2-hidroksie-etiel)-N'-benzieltioureum(HL 3) en Npiperidiel- N'-4-nitrobenzieltioureum(HL9 ), doeltreffend en selektief was vir Ag(l) transportasie. HL9 was selektief vir Ag(I), maar die transportasie waarde was nie hoog nie, dws. dit was nie doeltreffend nie. HL3 was selektief vir Cu(II). Met gebruik van ons eksperimentele kondisies is 13% Cu(lI) getransporteer deur HL 3. Van die N,N-dialkiel-N'- ariel tioureums, is maksimum transportasie van Ag(l) verkry met gebruik van N,N-dietiel- N'-4-chlorobenzieltioureum (HL5) en N,N-di-n-butiel-N'-benzieltioureum (HL1). Met gebruik van ons eksperimentele kondisies was die persentasie transportasie van Ag(l) deur HL5 en HL 1 48% en 42% onderskeidelik. Die selektiwiteit en doeltreffendheid van 3,3,3' ,3'-tetra-etiel-1 ,t-isoftaltelblstioureumtl+L 12) en N,N-di-etiel-N'-kamfonieltioureum (HL13) vir Ag(l) transportasie is ook onderneem. Ons was besonder ge-interesseerd om die Ag(l) transportasie en ekstraksie van hierdie ligande te vergelyk met dié van die HL en H2L tipe ligande. Die eksperimentele resultate het getoon dat van al die ligande wat bestudeer is, HL 13 die doeltreffendste en mees selektiewe ionofoor was. Van besondere, belang was dat, afhangend van die ligand konsentrasie wat gebruik is, HL13 71-81% Ag(l) getransporteer het. Kompeterende twee-fase metaalioon vloeistof-vloeistof ekstraksie eksperimente is ook uitgevoer onder toestande soortgelyk aan dié van die transportasie eksperimente. Die resultate toon dat met varierende ligand konsentrasie, tot soveel as 100% Ag(l) selektief en doeltreffend geëkstrakeer word vanuit 'n mengsel van die sewe metaal ione. N,N-di-n-butiel-N'-benzieltioureum (HL1 ) ligande en die kompleks daarvan met Ag(l) is ook gesintetiseer. Enkel-kristalle van die kompleks is verkry en X-straal kristallografiese analiese is onderneem. Die kristalstruktuur toon hoedat Ag(l) gebind is aan die gedeprotoneerde ligand deur die S en Q atome en toon ook interessante [Ag(L-S,Q)]4 groepe in die vaste toestand. Hierdie struktuur is monoklinies en kristaliseer in die ruimtegroep P21!c met a = 17.805(4) Á, b = 21.759(4)Á, c = 36.438(7)Á, P = 96.34(3t, z = 8 en 'n finale R-faktor van 5.4%.
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24

Mougenot, Pierre. "Etude theorique ab initio scf et ci de complexes organometalliques binucleaires." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13025.

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Analyse approfondie du spectre photoelectronique se(fe(c::(5)h::(5)))::(2)(no)::(2). Etude critique des resultats experimentaux anterieurs concernant le diamagnetisme suppose se(co(c::(5)h::(5)))::(2)(no)::(2). Bon accord avec l'experience dans l'etude theorique de l'etat fondamental du cation dirhodium tetraacetate dihydrate. Etude sur la nature de l'interaction metal-metal dans (v(c::(5)h::(5)))::(2) (c::(8)h::(8))
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25

Ghebregziabiher, Berhe Haile. "Synthesis of chiral thiourea ligands and their transition metal complexes." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53610.

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Thesis (MSc)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: Modification of chitosan with benzoylisothiocyanate was attempted, however due to solvent problem the study was left incomplete till appropriate solvent is designed. N,N-diethyl-N -camphanoylthiourea (HL8), N-piperidyl-N '-camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthiourea (HL10) and N,N-diethyl-N -adamantylcarbonyl thiourea (HL11)have been synthesised and characterised for the first time. Two of these ligands HL8 and HL11, were used to form a number of transition metal complexes, namely H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], translcis-[Zn(L 8_S,0)2], translcis-[Pt(L 8_S,0)2], Ag2[(HL8-S)(L-J.1-S,O)]2, translcis- [Ni(L11-S,O)2]and translcis-[Cu(L11_S,O)2]. The new products are fully characterised by means of MS, IR spectroscopy, NMR spectroscopy, elemental (C, H, Nand S) analysis and melting point determinations. The H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8- S,O)2], trans-[Cu(L8-S,O)2] and Ag2[(HL8-S)(L-J.1-S,O)]2 are also characterised by Xray diffraction analysis. The structure of the new chiral N,N-dialkyl-N' -camphanoylthiourea ligand (HL8) has a significant effect on its coordination chemistry with transition metal ions. This ligand forms H30+ {fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,O)2] and Ag2[(HL8- S)(L8-J.1-S,O)]2 complexes with the Co(II), Ni(II), Cu(II) and Ag(I) metal ions respectively. The spectroscopic and X-ray diffraction results of these complexes indicate a bidentate mode of coordination of the ligand (with its Sand °donor atoms) to the Co(II), Ni(II) and Cu(II) metal ions. The reaction of this ligand with silver(I) however affords the formation of a binuclear silver(I) complex exhibiting monodentate and bidentate modes of coordination within the same complex. The exclusive formation of trans-[Cu(L8-S,0)2] is a new phenomenon for the HL type thiourea ligands with Sand °donor atoms. Up to this point a maximum of 15 % trans-isomer has been reported in ltterature." All the transition metal complexes made with HL8and HL11are air stable in both the liquid and solid states except the H30+{fae-[Co(L 8-S,Ob]} Interestingly the deep green fae- H30+{fae-[Co(L8-S,Obn complex is air sensitive and the Co(II) oxidizes to Co(III) in the complex by atmospheric O2. The oxidation of Co(II) to Co(III) in the complex is confirmed by 1Hand 13CNMR spectra as well as by UV-Visible spectra of the complex. The NMR spectra of the complexes indicated the presence of one isomer in each complex except for the NMR spectra of the platinum complex of the HL8 ligand. The presence of the minor trans-[Pt(L8-S,Q)21 isomer in combination with the major cis-[Pt(L8-S,Q)21 isomer in the platinum complex was indicated by the 1H, 13Cand 195ptNMR spectra of the complex.
AFRIKAANSE OPSOMMING: Pogings om chitosan met benzoylisothiocyanate te modifiseer is onvoltooid gelaat weens die gebrek aan'n geskikte oplosmiddel. N,N-diethyl-N -carnphanoylthiourea (HL8), N-piperidyl-N -camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthlourea (HL10) en N,N-diethyl-N -adamantylcarbonyl thiourea (HL11) is vir die eerste keer gesintetiseer en gekarakteriseer. Twee van die ligande, HL8 en HL11, is gebruik om verskeie oorgangsmetaalkomplekse te berei, nl. H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], trans/cis-[Zn(L8 - S,0)2], trans/cis-[Pt(L8-S,0)2], Ag2[(HLB-S)(L-jl-S,0)]2, trans/cis-[Ni(L11-S,0)2] en trans/cis-[Cu(L11_S,0)2]. Die nuwe produkte is volledig gekarakteriseer deur middel van MS, IR spektroskopie, KMR spektrometrie, elemente (C, H, N en S) analise en smeltpuntbepaling. Die komplekse H30+{fao-[Co(L8-S,0)3n, cis-[Ni(L8-S,0)2], trans- [Cu(L8-S,0)2] en Ag2[(HLB-S)(L-jl-S,0)]2 is ook deur middel van X-straaldiffraksieanalise gekarakteriseer. Die struktuur van die nuwe chirale N,N-dialkyl-N'-camphanoylthiourea ligand (HL8) het In beduidende invloed op die koordinasie van hierdie ligand met oorgangsmetaalione. Die ligand vorm H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,0)2] en Ag2[(HL8-S)(L8-Il-S,0)]2 komplekse met Co(ll)-, Ni(II)-, Cu(II)- en Ag(I)-ione respektiewelik. Spektroskopiese en X-straaldiffraksie-analise van die komplekse toon dat die ligande op 'n bidentate wyse d.m.v. die S- en O-donoratome met Co(II), Ni(lI) en Cu(lI) koordineer. Die reaksie van hierdie ligand met Ag(I)-ione lei egter tot die vorming van 'n dikernige silwer(I)-kompleks waarin die ligande monodentaat (S) en bidentaat (S en 0) aan die metaal gebind is. Die vorming van uitsluitlik die trans-[Cu(L8-S,0)2] in die reaksie van HL8 met Cu(lI) is 'n besondere fenomeen in die chemie van hierdie tipe ligande; in die literatuur word melding gemaak van slegs een ander trans-kompleks met hierdie ligande, en dan wel met 'n maksimum opbrengs van 15%.29 Alle oorgangsmetaalkomplekse met HLB en HL11 is stabiel indien blootgestel aan lug, ongeag of die verbindings opgelos word of in die vastetoestand verkeer, behalwe H30+{fao-[Co(L8-S,Ohn. Die diep-groen gekleurde H30+{fao-[Co(L8-S,Ohn)3]} kompleks is lugsensitief; Co(lI) word deur lugsuurstof na Co(lIl) ge-oksideer. Die oksidasie in die kompleks kan deur middel van 1H en 13CKMR spektrometrie sowel as UV-sigbare spektrofotometrie bevestig word. Die KMR spektra van alle komplekse dui op die teenwoordigheid van slegs een isomeer in oplossing, behalwe in die geval van die platinum(lI) kompleks met HL8. Die teenwoordigheid van lae konsentrasies trans-[Pt(L8-S,0)2] isomeer tesame met veel hoër konsentrasies van die cis-[Pt(L8 -S,O)2] isomeer word deur 1H, 13Cen 195ptKMR spektroskopie aangedui.
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26

Jasim, Naseralla. "Transition metal bifluoride complexes." Thesis, University of York, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323538.

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27

Barron, Andrew Ross. "Transition metal aluminohydride complexes." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/37935.

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28

Clavaud, Cécile. "Rhéoépaississement des suspensions denses : mise en évidence de la transition frictionnelle." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0260/document.

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Le rhéoépaississement est un phénomène spectaculaire apparaissant dans certaines suspensions concentrées en particules. Il se manifeste par l’augmentation brutale de la viscosité de la suspension au delà d’une contrainte critique. L’exemple emblématique de suspension présentant ce type de comportement est le mélange d’amidon de maïs et d’eau. Le rhéoépaississement est longtemps resté une énigme, jusqu’à des travaux théoriques et numériques récents proposant un modèle microscopique cohérent. Selon celui-ci, le rhéoépaississement provient d’une transition frictionnelle due à la présence d’une force répulsive entre les grains. Au cours de ma thèse, j’ai réalisé une des premières démonstrations expérimentales directe de ce mécanisme. En m'inspirant de travaux venant du domaine des milieux granulaires, j'ai montré qu'en accord avec le modèle de transition frictionnelle, une suspension rhéoépaississante possède à faible pression granulaire un état non frottant. J'ai ensuite mis en évidence la transition en elle-même dans des suspensions contrôlées de billes de silice dans des solutions salines. Pour cela, j'ai dû développer de nouvelles méthodes de rhéologie à pression imposée. En effet, les rhéomètres standard ne permettent pas d'accéder aux propriétés de frottement des suspensions. Le seul rhéomètre qui le permet n'est pas adapté aux suspensions étudiées ici, qui sont constituées de particules colloïdales. Ce travail ouvre donc la voie au développement d’une nouvelle génération de rhéomètres permettant de mesurer le frottement dans les suspensions colloïdales, un enjeu majeur pour la rhéologie des fluides complexes
Shear thickening is a spectacular phenomenon which takes place in some dense suspensions. It manifests itself by a brutal increase of the suspension's viscosity above a certain critical stress. The most iconic example of shear-thickening suspensions is cornstarch and water mixes. Shear thickening long remained a mystery, until recent theoretical and numerical works which proposed a consistent microscopic model. This model explains the shear thickening transition as a frictional one due to the presence of a repulsive force between the grains.During my PhD, I provided one of the first direct experimental proofs of this mechanism. Inspired by granular physics, I showed that shear-thickening suspensions possess a frictionless flowing state at low granular pressure, which is consistent with the proposed model. I then evidenced the frictional transition with controlled experiments using suspensions of silica beads in ionic solutions. To do this, I developed new rheological techniques enabling pressure imposed measurements. Indeed, standard rheological tools do not allow access to the frictional properties of suspensions. The only rheometer that does that is not adapted to the suspensions we study here, which are colloidal. This work thus paves the way for the development of a new generation of pressure imposed rheometers, giving access to colloidal suspensions friction, which is a major challenge in complex fluids rheology
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29

Alnagi, Omar. "Reaction de la trimethylphosphine sur les sels de cobalt (ii) : synthese des complexes pentacoordonnes cox::(2)(pme::(3))::(3) (x=c1**(-), br**(-), i**(-), ncs**(-), no::(2)**(-)), reactivite vis-a-vis de petites molecules co, no et o::(2)." Toulouse 3, 1987. http://www.theses.fr/1987TOU30048.

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Synthese et etude physicochimique des complexes. Reactivite. Etude cristallographique de la structure indiquant une geometrie de bipyramide trigonale deformee quand x**(-)=cl**(-),br**(-),i**(-),ncs**(-) et une geometrie de pyramide a base carree pour x=no::(2)**(-). Etude des substitutions par co,no et o::(2)
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30

Rimmelin, Jean. "Etude des relations structure-reactivite electrochimique dans quelques clusters du cobalt et du rhodium." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13176.

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Etude comparative des proprietes redox de treize clustres du co, rh, fe effectuee par des methodes electrochimiques (edt, coulometrie, voltamperometrie cyclique) associees a des methodes spectroscopiques (uv, rmn, rpe)
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31

Getty, April D. "Syntheses and reactivity studies of hydroxo-palladium(II) and amido-platinum(IV) complexes /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/8653.

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32

Fullaway, Phillip V. "α-Diimine complexes of transition metals for the polymerisation of lower α-olefins." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/2341.

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Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2005.
In this study several potential polymerisation catalysts were synthesised. This was accomplished by coordinating α-diimine ligands such as N,N'-diferrocenyldiazabutadiene (DFDAB), N,N'-dimesityldiazabutadiene (DMDAB) as well as the bidentate amine N,N,N',N'-tetramethylethylenediamine (TMEDA), to several transition metals. The multi-step synthesis of N,N'-diferrocenyldiazabutadiene (DFDAB) from ferrocene involved the use of lithiated ferrocene, iodoferrocene, N-ferrocenylphthalimide and aminoferrocene; the latter three were characterised. This ligand was coordinated to the transition metal ions iron(II) and zinc(II) to form Fe(DFDAB)Cl2 and Zn(DFDAB)Cl2 respectively. 1H and 13C NMR, FT-IR and mass spectrometry revealed that the expected product had been synthesised in a useful form. 2,4,6-Trimethylaniline reacted with glyoxal to form N,N'-dimesityldiazabutadiene (DMDAB). The DMDAB ligand was coordinated to the transition metal ions zinc(II) and silver(I) to form Zn(DMDAB)Cl2 and Ag(DMDAB)2 respectively. Characterisation now also include molecular and crystallographic structural determinations by means of X-ray diffractometry. Another N-donor complex, Cr(CO)4(TMEDA), was also prepared by coordinating N,N,N',N'-tetramethyl ethylenediamine (TMEDA) to Cr(CO)5(THF). This was done to give an indication of the activity of low oxidation state complexes in the catalysis of olefin polymerisation. The metal-α-diimine complexes mentioned above were employed in the polymerisation of the monomers ethylene and 1-pentene probably according to a cationic mechanism. High density, high molar mass polyethylene products with narrow polydispersities were obtained. The chromium(TMEDA) complex produced polyethylene exhibiting ultra-high molar mass (> 10 000 kg/mol). The polymerisation of 1-pentene, using the Fe(DFDAB)Cl2 complex, afforded oligo-pentene with a molar mass of ~800 g/mol. After an unsuccessful attempt to prepare the (CO)5Cr=C(OZrCp2Cl)(ferrocenyl) modified Fischer-type carbene complex, the (CO)5Cr=C(OMe)(ferrocene) complex was eventually insolated. Elucidation of its molecular structure was accomplished by X-ray diffractometry. Finally, the DFDAB-ligand was coordinated to Fe2(CO)9 to generate Fe(CO)3(DFDAB) in another attempt to investigate the role of carbonyl groups and also low oxidation state metals in polymerisation reactions [compare to Cr(CO)4(TMEDA) unit above]. The sensitivity of this complex towards moisture and air prevented such action.
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33

Veighy, Clifford Robert. "Novel cyclopentadienyl transition metal complexes." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327366.

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34

Johnson, Donald Martin. "Cyanoscorpionates and Transition Metal Complexes." Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etd/1725.

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The new dihydrobis(4-cyano-3-tert-butylpyrazolylborate) ligand has been synthesized. Isolated crystals of the thallium complex were collected and structurally characterized by X-ray diffraction. Transition metal complexes of the ligand are currently under investigation.
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35

Zard, P. W. "Transition metal complexes with pyrimidinethiones." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47322.

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36

Longley, C. J. "Alkylimido complexes of transition metals." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47157.

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37

Gallé, Geoffrey. "Étude de la photo-commutation de complexes du fer : comportements individuels et collectifs." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14476/document.

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Ce travail de thèse porte sur l'étude des propriétés optiques des composés à transition d'état de spin (TS). Nous avons plus précisément caractérisé la transition photo-induite faisant passer les complexes de Fe(II) de l'état bas-spin (BS) vers l'état haut-spin (HS) et réciproquement. Ces molécules on été étudiées à la fois sous forme solide et en solution. À l'état solide, La TS des complexes moléculaires que nous avons étudié présente une boucle d'hystérésis thermique proche de la température ambiante. En plaçant ces composés à une température comprise dans cette dernière, il est alors possible de faire photo-commuter partiellement ou complètement ce type de molécule. Après avoir étudié les paramètres influençant l'efficacité de la TS photo-induite, nous avons réalisé un montage permettant d'enregistrer la dynamique de cette transition dans la boucle d'hystérésis.Dans un second temps, nous avons dissous ces molécules dans un solvant adéquate, afin d'étudier les mécanismes élémentaires, à l'échelle de la molécule, qui sont à l'oeuvre lors de la TS. Nous avons plus particulièrement étudié deux complexes: [Fe(phen)3](BF4)2 et [Fe(2-CH3-phen)3](BF4)2. Le premier se présente à l'état BS à température ambiante, tandis que le second est à l'état HS. Nous avons alors révélé l'ensemble des étapes faisant commuter le premier complexe de l'état BS vers l'état HS et le second de l'état HS vers l'état BS. Dans une troisième et dernière partie, nous avons étudié la photo-isomérisation d'un cristal de Na2[Fe(CN)5NO].2H2O. Sous l'effet d'une excitation laser, le radical N-O peut réaliser une rotation sur lui même, soit de 90°, soit de 180°. Nous avons alors mesuré la dynamique de cette isomérisation photo-induite avec un montage, pompe visible, sonde infrarouge (~5µm)
This work deals with the study of the optical properties of spin cross-over (SCO) compounds. More precisely, we have characterized the photo-induced transition leading iron(II) SCO complexes from their low-spin (LS) to their high-spin (HS) states and conversely. These molecules have been studied in the solid state and in solution.In the solid state, our compounds display a thermal hysteresis loop at room temperature. When the temperature of the compounds is set inside their hysteresis loop, it is possible to switch them optically from the LS state to the HS state. First, we have studied the parameters impacting on the efficiency of the photo-induced SCO. Then, we have built an experimental set-up that makes it possible to record the kinetics of this transition inside the hysteresis loop. This latter experiment has confirmed our hypothesis that this phase transition is induced by a laser heating of the sample.In solution, we have studied, by means of time-resolved UV-visible pump-probe experiments, the elementary mechanisms involved in the SCO phenomenon. We focused our attention on two complexes: [Fe(phen)3](BF4)2 and [Fe(2-CH3-phen)3](BF4)2. The first one is in the LS state at room temperature, whereas the other one is in the HS state. Thanks to these experiments, we have evidenced and measured the lifetimes of the energy levels involved in the SCO at the molecular level.Finally, we have studied the photo-isomerization of a Na2[Fe(CN)5NO].2H2O crystal. By means of transient absorption experiments combining visible and infrared femtosecond pulses, we have evidenced the levels involved in this phase transition
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38

Medoukali-Daamach, Sakina. "Contribution a l'etude des phenomenes cinetiques en extraction liquide-liquide : cas de l'extraction du palladium (ii) par les sulfures de dialkyle en milieu acide chlorhydrique." Paris 6, 1988. http://www.theses.fr/1988PA066629.

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39

Wan, Susan Wai Yee. "Heterobimetallic complexes of the early transition metals." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284050.

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40

Giraudon, Jean-Marc. "Complexes mono et dinucléaires du molybdene avec les ligands macrocycliques : synthèse, structure, réactivité et propriétés redox." Brest, 1988. http://www.theses.fr/1988BRES2019.

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Preparation des complexes avec le coordinat tetraazaannulene; cas de complexes a liaison quadruple du mo ou le coordinat organique presente une coordination tetradentee. On envisage les mecanismes d'interconversion monomere oxo-dinucleaire. Etudes rpe et uv-visible
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41

Fraser, Kelly A. "Crystallographic studies of complexes of transition and post-transition metals." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238817.

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42

Paiva, Sofia Larissa da Costa. "Aplicação de modelos de defeitos na geração de conjuntos de teste completos a partir de Sistemas de Transição com Entrada/Saída." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-11072016-172020/.

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O Teste Baseado em Modelos (TBM) emergiu como uma estratégia promissora para minimizar problemas relacionados à falta de tempo e recursos em teste de software e visa verificar se a implementação sob teste está em conformidade com sua especificação. Casos de teste são gerados automaticamente a partir de modelos comportamentais produzidos durante o ciclo de desenvolvimento de software. Entre as técnicas de modelagem existentes, Sistemas de Transição com Entrada/Saída (do inglês, Input/Output Transition Systems - IOTSs), são modelos amplamente utilizados no TBM por serem mais expressivos do que Máquinas de Estado Finito (MEFs). Apesar dos métodos existentes para geração de testes a partir de IOTSs, o problema da seleção de casos de testes é um tópico difícil e importante. Os métodos existentes para IOTS são não-determinísticos, ao contrário da teoria existente para MEFs, que fornece garantia de cobertura completa com base em um modelo de defeitos. Esta tese investiga a aplicação de modelos de defeitos em métodos determinísticos de geração de testes a partir de IOTSs. Foi proposto um método para geração de conjuntos de teste com base no método W para MEFs. O método gera conjuntos de teste de forma determinística além de satisfazer condições de suficiência de cobertura da especificação e de todos os defeitos do domínio de defeitos definido. Estudos empíricos avaliaram a aplicabilidade e eficácia do método proposto: resultados experimentais para analisar o custo de geração de conjuntos de teste utilizando IOTSs gerados aleatoriamente e um estudo de caso com especificações da indústria mostram a efetividade dos conjuntos gerados em relação ao método tradicional de Tretmans.
Model-Based Testing (MBT) has emerged as a promising strategy for the minimization of problems related to time and resource limitations in software testing and aims at checking whether the implementation under test is in compliance with its specification. Test cases are automatically generated from behavioral models produced during the software development life cycle. Among the existing modeling techniques, Input/Output Transition Systems (IOTSs) have been widely used in MBT because they are more expressive than Finite State Machines (FSMs). Despite the existence of test generation methods for IOTSs, the problem of selection of test cases is an important and difficult topic. The current methods for IOTSs are non-deterministic, in contrast to the existing theory for FSMs that provides complete fault coverage guarantee based on a fault model. This manuscript addresses the application of fault models to deterministic test generation methods from IOTSs. A method for the test suite generation based on W method for FSMs is proposed for IOTSs. It generates test suites in a deterministic way and also satisfies sufficient conditions of specification coverage and all faults in a given fault domain. Empirical studies evaluated its applicability and effectiveness. Experimental results for the analyses of the cost of test suite generation by random IOTSs and a case study with specifications from the industry show the effectiveness of the test suites generated in relation to the traditional method of Tretmans.
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43

Foulet-Fonseca, Gloria. "Etude par spectroscopie vibrationnelle des complexes méthylcarbyniques et méthylcarbéniques de chrome." Paris 13, 1987. http://www.theses.fr/1987PA132028.

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Etude en particulier de complexes, du type br(co)::(4)crcch::(3), br(co)::(4)crcchd::(2) et d'une série de mélanges isotopiques. Mise en évidence de la non-équivalence des liaisons c-h du groupe methyle. Etablissement d'un champ de forces pour les complexes méthylcarbyniques
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44

Etienne, Michel. "Réactivité de complexes dinucléaires hydrure et alcénylidène ponte du fer vis-a-vis d'hydrocarbures cyanes insatures (mono et dicyanoacétylène, tétracyanoethylène)." Brest, 1988. http://www.theses.fr/1988BRES2009.

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Preparation de complexes avec des coordinats cyano-4 butadienyldene portants. On obtient egalement des complexes dinucleaires avec le tricyano-3,4,4 butadienylidene-1,3. Mecanisme ses reactions de migration de l'hydrogene allylique
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45

Zhu, Jun. "Theoretical studies on bonding in platinum boryl and metallabenzene complexes and mechanisms of ruthenium/osmium mediated allene insertion reactions and molybdenum/tungsten catalyzed alkyne metathesis /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202007%20ZHU.

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46

Xie, Jin. "Synthesis, structures and spectroscopic properties of primary and secondary phosphine complexes of iron, ruthenium and osmium porphyrins." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39556876.

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47

Hanson, Susan Kloek. "Synthesis and reactivity studies of late transition metal complexes relevant to C-H bond activation and functionalization /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8631.

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48

Lam, Wai Han. "Structural features of transition metal complexes having ligands with different electronic properties and mechanistic aspect of C-H bond activation and functionalization by transition metal complexes /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202003%20LAMW.

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Cheung, Wai Man. "Transition metal complexes with dichalcogenoimidodiphosphinate ligands /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202007%20CHEUNG.

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50

Humphrey, Paul Andrew. "A study of transition metal complexes /." Title page, contents and summary only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phh9262.pdf.

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