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Dissertations / Theses on the topic 'Valence'
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1
Balsan, Alain. "Valence au grand siècle /." Valence : E & R, 2000. http://catalogue.bnf.fr/ark:/12148/cb38805647c.
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Derr, Julien. "Valence, magnétisme et conduction dans les composés à valence intermédiaire : Le cas SmB6." Phd thesis, Université Joseph Fourier (Grenoble), 2006. http://tel.archives-ouvertes.fr/tel-00133598.
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Le composé SmB6 est un exemple typique de la physique étrange qui peut résulter d'un équilibre de valence. La première configuration du Samarium (Sm2+) correspond à un état isolant non magnétique alors que la seconde (Sm3+) donnerait théoriquement un état magnétique et conducteur. Des mesures de microcalorimétrie sous pression ont permis d'établir le diagramme de phase magnétique de SmB6 : une nouvelle phase magnétique ordonnée à longue distance a été mise en évidence pour des pressions supérieures à 10GPa. D'un autre coté, des mesures de transport réalisées sous pression hydrostatique permettent de situer la transition isolant-métal pour la même pression. Le diagramme de phase sous pression est désormais bien établi et l'observation pour la première fois d'une anomalie magnétique dans les courbes de résistivité au delà de 10GPa permet d'affirmer que la coïncidence des deux phénomènes a bien lieu. Ce changement de comportement du système est discuté dans un nouveau cadre théorique prenant en compte la température Kondo du réseau comme paramètre clef pour la renormalisation de la fonction d'onde vers l'une ou l'autre configuration de valence entière alors que la valence mesurée est toujours nettement intermédiaire. Cette idée générale semble par ailleurs s'appliquer à d'autres composés à valence intermédiaire étudiés (SmS, TmSe). En parallèle, des mesures de résistivité sous contraintes uniaxiales ont été réalisées. Elles mettent en évidence un fort effet d'anisotropie dans le composé SmB6. La comparaison de ces expériences avec les résultats obtenus dans des conditions de pression très hydrostatiques permettent de revisiter le problème de la nature du gap de SmB6.
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Davis, M. J. "Valence-Electron-Only Valence Bond calculations on the low lying states of Na-S." Thesis, University of Bristol, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384414.
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Faraon, Montathar. "Valence asymmetry in impression formation." Thesis, Kristianstad University College, Department of Behavioural Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-4402.
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Are implicit attitudes as easily formed as explicit attitudes? Fifty-four participants carried out an experiment regarding the behaviors of a fictional protagonist. Attitudes were obtained by the Implicit Association Test (IAT) and by explicit evaluations. The results in the current study showed tendency towards a significant persistence effect for explicit attitudes and a positivity bias effect for implicit attitudes.
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Gonen, Ozgur. "Modeling planar 3-valence meshes." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85883.
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In architectural and sculptural practice, the eventual goal is constructing the
shapes that have been designed. Due to fabrication considerations, shapes with planar
faces are in demand for these practices.
In this thesis, a novel computational modeling approach to design constructible
shapes is introduced. This method guarantees that the resulting shapes are planar
meshes with 3-valence vertices, which can always be physically constructed using
planar or developable materials such as glass, sheet metal or plywood. The method
introduced is inspired by the traditional sculpture and is based on the idea of carving
a mesh by using slicing planes. The process of determining the slicing planes can
either be interactive or automated.
A framework is developed which allows user to sculpt shapes by using the in-
teractive and automated processes. The framework allows user to cut a source mesh
based on its edges, faces or vertices. The user can sculpt various kinds of developable
surfaces by cutting the parallel edges of the mesh. The user can also introduce in-
teresting conical patterns by cutting dierent vertex, edge, face combinations of the
mesh.
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Brown, Neil John. "Novel organometallic mixed valence complexes." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/417/.
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Organometallic mixed valence complexes have been studied extensively over the past 30 years providing many synthetic and theoretical challenges. This thesis has sought to provide the field with a unique family of mixed valence complexes through which theories of electron transfer in weakly coupled systems can be tested. The metal fragment Mo(dppe)(η7-C7H7) is unique amongst its half-sandwich counterparts providing low formal oxidation states and a well resolved EPR signal and forms the basis of these studies. Before undertaking a study of the electronic structure of [{(Mo(dppe)(η7-C7H7)}2{μ- C≡CXC≡C}]n+ systems, and associated issues regarding mixed valence characteristics and carbon-chain mediated metal-metal interactions, mono-metallic molybdenum acetylide complexes that serve as model systems were studied in detail and their electronic structure fully rationalised. Thus, in Chapter two, a range of para substituted molybdenum aryl acetylides, Mo(C≡CC6H4X-4)(dppe)(η7-C7H7), featuring a range of electron-donating and -withdrawing substituents, are described. These compounds have been studied using a range of spectroscopic, crystallographic, electrochemical, spectroelectrochemical, and computational techniques establishing metal centred oxidation character. This is a consequence of cycloheptatrienyl ring destabilising the filled dz2 metal d-orbtial which then forms the HOMO. The poor symmetry match of this dz2 orbital and the alkynyl π-system effectively decouples the molybdenum fragment from the alkynyl substituent. As a precursor to the synthesis and understanding of bi-metallic complexes containing all-carbon bridging moieties, a series of mono-metallic compounds containing diynyl and triynyl ligands have been studied in Chapter three. The subsequent elucidation of the influence of the length of the carbon chain on the electronic structure has been studied using a combination of spectroelectrochemical and computational techniques. These studies reveal that the length of the carbon chain, and the identity of the supporting ligand, (bipyridine or dppe) increases the chain character of the frontier orbitals. Homo-bimetallic complexes containing a bis(ethynyl) substituted para-carborane bridging moiety were synthesised (Chapter four) together with the monometallic complex Mo(C≡CC2B10H11)(dppe)(η7-C7H7). The mono-metallic complex was first synthesised and studied to establish how the ethynyl carborane affects the electronic structure of the Mo(dppe)(η7-C7H7) centre and the nature of interaction between the molybdenum centre, the ethynyl fragment and the carborane cage. This preliminary work was followed by the synthesis of the bimetallic complex, [{Mo(dppe)(η7- C7H7)}2{μ-C≡C(C2B10H10)C≡C}]. Using a range of spectroscopic, spectroelectrochemical and computational techniques the electronic structure, and charge transfer process of [{Mo(dppe)(η7-C7H7)}2{μ-C≡C(C2B10H10)C≡C}]n+ (n = 0, 1 or 2) have been explored. The monocation [{Mo(dppe)(η7-C7H7)}2{μ- C≡C(C2B10H10)C≡C}]+ has shown to be a genuine example of a valence trapped, weakly coupled mixed valence complex allowing conventional descriptions of the intervalence transition to be compared with TD-DFT based interpretations. The literature surrounding the area of poly-carbon ligand chemistry indicates that the butadiyndiyl bridging moiety is an efficient conduit for electron transfer, due to its two orthogonal π-systems that span across the entirety of the ligand, leading to systems which are generally delocalised. An investigation of the mixed valence complex, [{Mo(dppe)(η7-C7H7)}2(μ-C≡CC≡C)]+ reveals a weakly coupled, localised mixed valence electronic structure, which is unique amongst its poly-carbon counterparts (Chapter five). Through using a range of spectroscopic timescales (EPR /IR /UV /vis) the rate of electron transfer has been estimated. To fully account for the number of transitions in the NIR region and the shape of the resulting absorption bands, it is necessary to employ a three state approximation (which explicity indicates the bridge state) when describing the electron transfer process. The complex [{Mo(dppe)(η7-C7H7)}2{μ-C≡C(C6H4)C≡C}]n+ has been studied using a range of spectroscopic, electrochemical and computational methods to establish the nature and rate of electron transfer of the mixed valence complex (Chapter six). It has been demonstrated that the 1,4-diethynylbenzene bridge mixes more efficiently with the Mo(dppe)(η7-C7H7) than the 1,3-butadiyndiyl bridge. Spectroscopic analysis revealed a moderately coupled, localised mixed valence complex, where the rate of electron transfer is much faster than the diynyl complex but not faster than the infrared spectroscopy timescale. The application of the three state model in the description of the charge transfer process allows the increased electron transfer rate to be explained through the increased mixing of the bridge with the Mo(dppe)(η7-C7H7) moiety, characterised by the lowering of the LMCT transition in comparison to carboranyl and diynyl containing complexes. Metal complexes containing the cyanoacetylide moiety, C≡CC≡N, have been known for several decades, but despite the obvious synthetic advantages of cyanoacetylide as a bridging moiety compared to a butadiyndiyl bridge, C≡CC≡C, the C≡CC≡N ligand has been largely ignored. Chapter seven summarises attempts made to provide a convenient route to complexes containing the cyanoacetylide moiety so that a greater variety bimetallic complexes can be synthesised, thus allowing the investigation of the charge transfer characteristics of [{LxM}(μ-C≡CC≡N){MLx}]n+ complexes. Reactions of cyanogen bromide with metal acetylide complexes yield novel mono- and di- bromovinylidenes rather than cyano containing complexes. The cyanation reagent of choice is 1-cyano-4-dimethylaminopyridinium tetrafluoroborate ([CAP]BF4) which allows the ready synthesis of mono- and di-cyanovinylidenes, as well as the synthesis of cyanoacetylide containing complexes. The cyanating agent [CAP]BF4 is able to cyanate a range of metal acetylides, thus expanding the number of potential bimetallic complexes. The hetero-bimetallic complex [{Fe(dppe)(η5-C5H5)}(μ- C≡CC≡N){Mo(dppe)(η7-C7H7)}]PF6 has been synthesised and studied using a range of techniques and has demonstrated that the cyanoacetylide bridge promotes a more delocalised electronic structure for dicationic complexes than is found for the other ethynyl based ligands described in this thesis.
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MINGUEZ, RUBIO RAMON. "L'affaire Dreyfus à Valence (Espagne)." Dijon, 1989. http://www.theses.fr/1989DIJOL001.
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La première partie est un rappel des données historiques, du contexte espagnol, elle insiste sur la spécificité de Valence (tradition républicaine, effervescence d'une presse diversifiée) qui est un terrain privilégié pour l'appropriation du modèle français. La deuxième partie est consacrée à l'analyse de la presse. Une fiche signalétique est consacrée à chacun des journaux dont la tendance idéologique est dégagée et mise en relation avec les groupes et les fractions politiques. Par ailleurs, la liste de tous les articles parus sur l'affaire Dreyfus est donnée par journal et par ordre chronologique. La dernière partie montre comment Valence se mobilise dans un climat passionnel, à propos de "l'affaire" et comment chaque journal est amené à définir sa conception de la société : ainsi s'opèrent des glissements et des regroupements. L'analyse des réactions face au problème juif, à l'église, à l'armée et à la république permet de cerner la question et de démontrer que se développent les pôles extrêmes, en suivant la dichotomie dreyfusards antidreyfusards, au détriment des positions modérées. L'affaire Dreyfus determine une recomposition du paysage politique valencienThe first part is a reminder of the historical facts, and of the Spanish context. It emphasizes the specificity of Valence, (the republican tradition, the effervescence of a diversified press) which is a privileged terrain for the appropriation of a French model. The second part is dedicated to an analysis of the press. Each of the newspapers is presented in turn, giving its ideological tendency in relation with political groups and factions. Likewise, the list of all the articles which appeared on the Dreyfus affair is classified by newspapers and in chronological order. The last part shows the passionate reaction of Valence to the Dreyfus affair and how each newspaper and political group was led to define its conception of society, thus operating shiftings and regroupings. An analysis of the various reactions to the Jewish problem, to the church, to the army and the republic leads to a closer interpretation of the problem. It is found that two extremes developed through the Dreyfus affair, defined by the dichotomy Dreyfusards anti-Dreyfusards, to the detriment of the moderates. Thus a new political landscape appeared in valence
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Macpherson, Brendan P. "Discrete cyano-bridged mixed valence systems /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17778.pdf.
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Ghiti, Ali. "Valence band engineering in semiconductor lasers." Thesis, University of Surrey, 1990. http://epubs.surrey.ac.uk/842853/.
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This thesis is concerned with the improvement of semiconductor laser characteristics using valence band engineering. We first show that the combination of strain and quantum confinement can confer considerable advantages to long wavelength lasers. With sufficient built-in strain, the highest hole subband has a low effective mass and is well separated from the lower bands. The low effective mass reduces the carrier density needed for population inversion and leads to the virtual elimination of two important loss mechanisms: Auger recombination and intervalence band absorption. We propose a specific strained-layer 1.55mum structure that can reduce the threshold current density and its temperature dependence and increase the luminescent efficiency. The presence of strain can also lead to an enhancement of the relaxation oscillation frequency due to the higher differential gain when compared to lattice-matched structures. The linewidth enhancement factor is also predicted to be reduced. Such strained-layer lasers could be of major significance for long distance optical communication. However, the long term stability of these structures, although promising, has still to be fully assessed. In view of this, we suggest that (111) growth of unstrained structures could provide the light-hole cap to the valence band needed for laser operation. We find that the threshold current density in thin (111) lasers could be reduced while the polarisation selection of TE modes could be improved compared to equivalent (001) lasers. Finally, we consider the effects of crystal orientation and of strain on the exciton binding energy.
10
Costi, T. A. "Electronic properties of intermediate valence compounds." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355734.
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Kim, Joshua Ph D. Massachusetts Institute of Technology. "Amygdala circuits underlying valence-specific behaviors." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/117881.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 54-61).
Threatening and rewarding stimuli evoke a set of distinct stereotyped behaviors, which can be categorized as negative and positive valence-related behaviors, respectively. The stereotypic nature of negative and positive valence-related behaviors suggests that threatening and rewarding stimuli engage evolutionarily predetermined neural circuits in the brain. The amygdala is an important mammalian brain region that is activated by negative and positive stimuli and mediates negative and positive valence-related behaviors. The current prevailing circuit model of the amygdala mainly considers negative behaviors and only recently has cell-type specific models have been proposed. Hence, the substrates, genetically distinct neuronal populations, for negative and positive behaviors are not known. The work presented here describes a genetically-defined amygdala circuit model for negative and positive behaviors. Development of a genetic-based circuit model of the amygdala revealed anatomical and genetic circuit motifs that underlie that amygdala circuits that mediate valence-specific behaviors.
NIH Pre-Doctoral Training Grant T32GM007287 RIKEN Brain Science Institute
by Joshua Kim.
Ph. D.
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Maître, Philippe. "Etude valence bond de radicaux hypervalents." Paris 11, 1990. http://www.theses.fr/1990PA112343.
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Dans la premiere partie de ce travail, nous proposons une methode de calcul generale de configurations pour des fonctions d'onde valence bond (bv) en base non-orthogonale, de facon a obtenir des energies fiables en tout point d'une surface de potentiel, diabatique ou adiabatique. La methode, testee pour des calculs de distance d'equilibre, de frequences de vibration, d'energies de dissociation ou de barrieres de reaction est en excellent accord avec les meilleurs calculs de reference dans une base d'oa equivalente. Nous l'utilisons ensuite pour calculer quantitativement les courbes diabatiques des diagrammes de correlation vb pour les deux modeles de reaction d'echange x#?+xx|xxx|#. Xx+x#. (x=h, li). Notre analyse nous conduit a reformuler la theorie originale (modele a deux courbes), mais confirme son hypothese fondamentale selon laquelle le profil de la reaction est seulement relie a une simple propriete des reactifs: l'ecart singulet-triplet du dimere xx. La seconde partie est consacree a la verification, a l'aide de calculs ab initio casscf+ci, des predictions d'une extension a trois courbes des diagrammes vb concernant la stabilite de ph#4 et sih#5, ce dernier faisant l'objet d'une controverse experimentale. Nos calculs confirment la stabilite de ph#4 et l'instabilite de sih#5. Finalement, nous proposons un nouveau mecanisme qui explique la stereochimie (observee experimentalement) de la reaction de pseudorotation dans les radicaux phosphoranyles
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Febrer, Romaguera Manuel Vicente. "Cartas pueblas de las morerías valencianas y documentación complementaria /." Zaragoza : Anubar ed, 1991. http://catalogue.bnf.fr/ark:/12148/cb36664424j.
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Lapenna, Michela. "Superconduttività alle alte temperature: resonating valence bond." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18734/.
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La presente tesi segue l’evoluzione storica delle scoperte e delle teorie nell’ambito della superconduttività.
Nel primo capitolo vengono trattati gli aspetti principali della teoria BCS, la cui denominazione è data dall’unione delle inziali dei suoi ideatori.
Questa teoria costituisce la prima descrizione generale dei materiali superconduttori ed è il riferimento solido delle teorie successive.
La teoria BCS riesce a spiegare il comportamento dei materiali superconduttori convenzionali con bassa temperatura critica, ma non è risultata sufficiente per comprendere la superconduttività alle alte temperature.
Nel secondo capitolo viene esposta la teoria RVB del Resonating Valence Bond, che nasce come prima risposta alla scoperta dei materiali superconduttori con alta temperatura critica.
La teoria RVB è una delle tante teorie nate a completare la teoria BCS e a differenza di questa non è riconosciuta all’unanimità.
Le conferme alla teoria RVB sono attualmente ricercate nel regime di pseudo-gap che precede lo stato superconduttivo nei materiali superconduttori non convenzionali.
Nel terzo capitolo vengono presentati i risultati più rilevanti dell’analisi dello pseudo-gap.
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Lancaster, Kelly. "Intramolecular electron transfer in mixed-valence triarylamines." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31709.
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Thesis (Ph.D)--Chemistry and Biochemistry, Georgia Institute of Technology, 2010.Committee Chair: Bredas, Jean-Luc; Committee Member: Kippelen, Bernard; Committee Member: Marder, Seth; Committee Member: Orlando, Thomas; Committee Member: Sherrill, David. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Michaels, Hannes. "Cu(I)/(II) mixed-valence Coordination Polymers." Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-330861.
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Poyraz, Mehmet. "Valence localisation in transition metal cluster complexes." Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389271.
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Maclean, Ewan Douglas William. "Valence losses at interfaces in aluminium alloys." Thesis, Connect to e-thesis, 2002. http://theses.gla.ac.uk/917/.
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Thesis (Ph.D.) -- University of Glasgow, 2002.Ph.D. thesis submitted to the Department of Physics and Astronomy and the Department of Chemistry, University of Glasgow, 2002. Includes bibliographical references. Print version also available.
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Latouille, Jean-Jacques Avanzini Guy. "L'université de Valence en Dauphiné (1452-2000)." Lyon : Université Lumière Lyon 2, 2003. http://theses.univ-lyon2.fr/sdx/theses/lyon2/2003/latouille_jj.
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Davis, Matthew Harris. "A Bond Valence-Based Force Field: A Multi-Body Approach." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3796.
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The typical form for a molecular mechanics force field consists of a foundation of pair-wise terms to describe bonded and non-bonded atomic interactions, with multi-body correction terms to deal with the limitations of pair-wise terms. I present here the first attempts of a molecular mechanics model that is founded on multi-body terms, which are based on the Bond Valence Model (Brown, 2002) and recent developments in the Vectorial Bond Valence Model (Bickmore et al., 2013a; Harvey et al., 2006). I calibrated these models on pressure vs. energy curves for a set of SiO2 polymorphs. The average deviation for the best-fit iteration, with only six adjustable parameters was ±1.98 kcal/mol.
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D'accriscio, Florian. "Complexes de nickel caméléons : exploration de tous ses degrès d'oxydation pour la formation de liaisons C-C et C-CF3." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30216.
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Ce projet de recherche porte sur l’étude de complexes de nickel à différents degrés d’oxydation (de 0 à +IV) dans le but de promouvoir la formation de liaisons C–C et C–CF3. Dans une première partie, l’étude porte sur l’utilisation de complexes de nickel à basse valence en tant que catalyseurs pour les réactions de couplage croisé de Negishi et de Suzuki-Miyaura. Si la formation de liaisons C–C est une réaction parfaitement maîtrisée au palladium, l’emploi de complexes de nickel comme catalyseurs est plus difficile à appréhender d’un point de vue mécanistique. Dans ce travail, l’utilisation d’un ligand bis-phosphine a permis de synthétiser et d’isoler des complexes de nickel(0). Une étude mécanistique complète alliant expériences et calculs DFT démontre que la réaction de Negishi fonctionne uniquement sur un régime Ni(0)/Ni(II). Des études préliminaires montrent en revanche que le mécanisme est tout autre lorsqu’on s’intéresse à la réaction de Suzuki-Miyaura. Dans une deuxième partie, l’objectif est la formation de liaisons C–CF3 en utilisant des complexes de nickel à haute valence. La formation de ces liaisons à partir de métaux de transition reste un défi puisque les méthodologies utilisées à ce jour au niveau industriel nécessitent l’utilisation de conditions drastiques et conduisent à la formation de composés nocifs pour l’environnement. Ce n’est que très récemment que des travaux de recherche ont porté sur l’utilisation du nickel comme support à la formation de liaisons C–CF3. Ce projet décrit la synthèse de complexe de nickel(III) portant deux groupements CF3 et l’utilisation d’un complexe dimérique de nickel(III) comme plateforme pour l’accès à d’autres complexes [NiIII(CF3)2]. Si ces complexes ne permettent pas de former de liaisons C–CF3, une espèce de nickel(IV) permet la formation de telles liaisons. Il s’agit de plus du premier complexe de nickel(IV) portant deux atomes de fluor et deux groupements CF3 capable de promouvoir l’activation de liaisons C–HThis research project aims at the study of nickel complexes in different oxidation states (from 0 to +IV) in order to promote C–C and C–CF3 bond formation. In a first part, low-valent nickel complexes are used as catalysts to perform Negishi and Suzuki-Miyaura cross-coupling reactions. If the C–C bond formation is a well-known reaction using palladium catalysts, the use of nickel complexes as catalysts is more complicated to understand in the mechanistic aspect. In this work, the key point is the use of a bis-phosphine ligand which allows the synthesis and isolation of nickel(0) complexes. A full mechanistic study via stoichiometric reactions as well as DFT calculations confirms that the Negishi cross-coupling works only on a Ni(0)/Ni(II) catalytic cycle. Surprisingly, preliminary studies on the Suzuki-Miyaura cross-coupling reactions show that the mechanism pathway is completely different. In a second part, our interest is focused on the C–CF3 bond formation using high-valent nickel complexes. In chemical industries, the C–CF3 bond formation requires harsh conditions and also produces toxic waste for the environment. This mainly explains why the use of transition metals is still challenging in this topic. However in the last few years, the interest for the use of nickel complexes as coupling agent for C–CF3 bond formation has grown. This work deals with the synthesis of nickel(III) complexes bearing two CF3 substituents and the use of a dimeric nickel(III) complex as a building block for the formation [NiIII(CF3)2] type complexes. If these species do not promote the C–CF3 cross coupling, a nickel(IV) complex shows its ability to create this bond. Moreover, this is the first nickel(IV) species bearing both fluorine and CF3 substituents at the same metal center and promoting C–H bond activation
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Tabai, Imen. "La solidarité morisque à l'épreuve du Saint-Office : les procès de Gil Pérez et d'Alonso Cornejo (Valence, 1580-1585)." Montpellier 3, 2009. http://www.theses.fr/2009MON30027.
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Après le soulèvement des morisques de l’ancien royaume de Grenade et de leur déportation en Castille (1568-1571) il ne restait dans la péninsule ibérique que deux régions où l’islam traditionnel avait pu se maintenir grâce à une forte densité de peuplement mudéjare et à une organisation communautaire intacte-les aljamas- : l’Aragon et surtout le royaume de Valence. C’est dans cette dernière région que les tentatives les plus sérieuses de sédition et de résistance aux pouvoirs chrétiens virent le jour, principalement après 1580. Il est malheureusement difficile d’en étudier la genèse, l’organisation et la portée, tant la légende s’est mêlée à la réalité, la propagande antimorisque ayant élaboré une véritable désinformation fondée sur la dénonciation de prétendues conspirations sécessionnistes ourdies par les morisques- vus comme une cinquième colonne- avec l’aide du pouvoir Ottoman. Afin de faire la part du mythe (soutenu par des peurs collectives) et de l’authentique dissidence morisque, nous avons eu recours aux archives de l’inquisition, acteur essentiel dans ce processus. L’affaire du soulèvement des années 1580-1585, ou affaire Pérez, du nom de son principal protagoniste, va de la sorte nous permettre d’étudier à la fois le divorce entre vieux et nouveaux chrétiens et les limites de la solidarité au sein des aljamas, dont les principaux acteurs étaient les élites des morisques, dans le cadre très concret du duché de Segorbe, pour lequel la documentation abonde. Dans le même temps, nous serons amenée à mettre en lumière le rôle, pour le moins troublant, joué par les agents du Saint-Office ainsi que par l’élite morisque tentée par l’intégrationAfter the revolution of Moriscos of the old Grenade kingdom and their deportation in Castille (1568-1571) it remained in the Iberian Peninsula, only two areas where traditional Islam had been able to be maintained thanks to a strong density of settlement mudéjare and with an intact Community organization -the aljamas-: Aragon and especially the kingdom of Valence. It is in this last area that the most serious attempts of sedition and resistance to the Christian capacities were witnessed after 1580. It is unfortunately difficult to study its genesis, its organization and its dimensions, as the legend merged with reality and as the anti-morisco propaganda having provided misleading information based on the denunciation of the alleged secessionists’ conspiracies warped by the moriscos- viewed as a fifth column of the Spanish society, consolidated by the assistance of the Ottoman authority. To distinguish myth (supported by collective fears) from authentic Morisco dissidence, we had recourse to the inquisition archives, essential actor in this process. The revolution of the years 1580-1585, or the “Pérez” case, as its name suggests, will enable us as a matter of fact to study simultaneously the rupture between old and new Christians and the limitations of the solidarity within the aljamas, whose principal actors were the morisco élites, within the very framework of the duchy of Segorbe, for which documentation abounds. At the same time, we are led to shed the light on the role, at the very least disconcerting, played by the agents of the Holy Office like by the morisco élite tempted with integration
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Makino, Yukio. "Chemical Interpretation of Superconductivity by Valence Electron Parameters." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188509.
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Tigges, David [Verfasser], and Mandy [Akademischer Betreuer] Hütter. "The Valence Illusion / David Tigges ; Betreuer: Mandy Hütter." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1187723665/34.
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KOULENTIANOS, DIMITRIOS. "Single photon double valence ionization of vinyl halides." Thesis, Uppsala universitet, Molekyl- och kondenserade materiens fysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-237105.
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Using a He lamp and a magnetic bottle spectrometer we measured the single ionization potential and the double ionization potential of C2H3Br, C2H3Cl, C2H4 and recorded their spectra at a photon energy of HeIIα and HeIIβ. The coincidence maps obtained from our measurements indicate that primarily direct double ionization occurs in these molecules. Due to the fact that ionization processes in this thesis involve valence electrons, we have tested the validity of an empirical equation,from which the distance of the holes created in the dication can be estimated if the values of the single and double ionization potential are known. It was found that the bond length between the carbon atoms was increased due to the repulsion of the holes created in the outermost valence orbitaland our data are in agreement with theoretical predictions, but in order to verify the applicability of this empirical relation on solid grounds, ab initio quantum chemical calculations are desired.
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Roos, Andreas. "Single photon double valence ionization of methyl monohalides." Thesis, Uppsala universitet, Molekyl- och kondenserade materiens fysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-239195.
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This thesis is based on experimental results from measurements on methyl halides at a photon energy corresponding to the He IIβ emission line. Double ionization processes involving the valence electrons of the molecules CH3F, CH3Cl and CH3I are studied by means of a magnetic bottle TOF-PEPECO spectrometer. Resulting double ionization data of these molecules suggest that mainly direct double photoionization is observed as a continuous energy sharing between the ejected electron pairs. As a mean to further understand the double ionization processes, a "rule of thumb", for double ionization in molecules, is applied to the data presented in the double ionization spectra. This is done in order to quantify the effective distance between the two vacancies created in the dications. It is found that the distance between the vacancies may be related to the bond distance between the carbon and halogen atoms. Further investigations call for quantum chemical calculations to scrutinize this hypothesis.Det här examensarbetet är baserat på experimentella fotojonisations studier av metyl halider vid en fotonenergi motsvarande He IIβ emissionslinjen. Valenselektronerna i dubbeljonisations processerna för CH3F, CH3Cl och CH3I har studerats under användning av en så-kallad magnetisk flask TOF-PEPECO spektrometer. Resultaten av dessa mätningar visar att mestadels direkt dubbeljonisation processer före- kommer, där elektronerna delar kontinuerligt på energin som friges vid jonisationen. Den dubbla jonisa- tions processen är ytterligare studerad genom att tillämpa en tumregel för dubbeljonisation i molekyler, vilket ger en indikation av hur stort avståndet är mellan de två vakanserna som skapades när molekylerna joniserade. Resultaten från tumregeln visar att avståndet mellan vakanserna kan vara relaterade till bind- ningsavståndet mellan kol-atomen och halogen-atomen, i respektive metyl halogen. För att ytterligare bekräfta dubbeljonisations processerna i dessa molekyler, krävs kvantmekaniska beräkningar.
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Bourgeois, Julie. "Les ferrites du type RFe2O4 à valence mixte." Caen, 2012. http://www.theses.fr/2012CAEN2009.
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LuFe2O4 appartient à la famille des ferrites RFe2O4 (R=Dy-Lu,Y) dont la structure peut être décrite comme un empilement selon c de couches compactes de [LuO2]∞ et [Fe2O4]∞. Ce composé fait l’objet de nombreux travaux depuis quelques années du fait de ses propriétés multiferroïques liées à de l’antiferromagnétisme en dessous de TN = 250K et de la ferroélectricité en dessous de 320K qui serait due à une mise en ordre polaire des charges Fe2+ et Fe3+ sur un réseau triangulaire. Lors de cette thèse, deux échantillons ont été tout particulièrement caractérisés en combinant la diffraction des rayons X au synchrotron, des neutrons et des électrons, avec des mesures des propriétés magnétiques, de transport et de constante diélectrique, et de la spectroscopie Mössbauer. L’étude de la structure à température ambiante a mis en évidence deux points importants : une légère déformation onoclinique de la maille qui est alors indexée en C2/m et un nouveau vecteur de modulation pour un seul des échantillons et qui a été attribué à une non-stœchiométrie en oxygène. Le omportement magnétique de LuFe2O4 s’est révélé particulièrement complexe, avec la coexistence de quatre phases magnétiques ordonnées, ferrimagnétiques ou antiferromagnétiques. Des mesures par diffraction des rayons X et des neutrons sous pression ont permis de mettre en évidence, de façon reproductible, une transition structurale irréversible à température ambiante, qui pourrait présenter une nouvelle mise en ordre des charges. En dessous de TN, l’amplitude du signal magnétique diminue avec la pression, dans la limite des 3GPa expérimentauxLuFe2O4 belongs to the rare-earth ferrite family RFe2O4 (R=Dy to Lu, Y), whose structure can be described as a stacking along c of [LuO2]∞ and [Fe2O4]∞ compact layers. This compound is attracting a lot of attention nowadays because of its multiferroic properties, linked to an antiferromagnetic spin ordering below Tn=250K and a ferroelectric state, based on a polar charge ordering of Fe2+ and Fe3+ species on a triangular lattice. In this work, two samples have been thoroughly investigated, combining synchrotron X-ray, neutron and electron diffraction techniques with magnetization, transport and dielectric constant measurements, as well as Mossbauer spectroscopy. Two main points have been evidenced: a slight monoclinic distortion of the room temperature crystal structure (SG C2/m), and a new structural modulation, dependent of the oxygen stoichiometry. The magnetic ground state of LuFe2O4 at low temperature is particularly complex, with several ferrimagnetic and antiferromagnetic magnetic phases co-existing. High pressure X-ray and neutron diffraction experiments have shown that LuFe2O4 undergoes an irreversible phase transition above 8GPa at room temperature, which could be linked with a new type of charge ordering. Below TN, increasing pressure up to the experimental limit of 3GPa leads to a decrease of the intensity of the magnetic scattering signal
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Haraux, Pauline. "Nouveaux systèmes intermétalliques 3d-4f à valence intermédiaire." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0033.
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Ce travail de thèse vient essentiellement compléter et préciser les études menées sur les composés YbMn6Ge6-xSnx et leurs dérivés au fer. Une seconde partie, plus exploratoire, porte sur l'identification de nouveaux composés associant une terre rare anormale et un sous-réseau 3d magnétique. La série YbMn6Ge6-xSnx présente des signatures de criticité quantique associé à l'instabilité magnétique de l'ytterbium vers x ~ 5 ,23. Les premières mesures de chaleur spécifiques réalisées dans le cadre de ce travail ont permis d'évaluer le caractère « fermions lourds » de ses alliages (γ > 100 mJ.K-2.mol-1). Elles corroborent en outre l'existence du point critique quantique vers x ~ 5 ,23, étant donné l'augmentation du coefficient de Sommerfeld γ (donc de la masse effective) dans les alliages correspondants, en accord avec les prédictions théoriques. Par ailleurs, des mesures XANES et XMCD sous pression, utilisant un milieu transmetteur à bas gradient (He), ont permis de déceler les prémices d'un pic dans la dépendance en pression des signaux, de façon analogue à ce qui est observé dans la dépendance en composition. Une étude thermoélectrique a confirmé l'intérêt de cette technique pour l'étude des systèmes à fermions lourds, avec une réponse thermoélectrique fortement dépendante de l'état de l'ytterbium. Les essais de substitution partielle du fer au manganèse dans les alliages YbMn6-yFeyGe0,85Sn5,15 (0,00 ≤ y ≤ 1,00) ont montré, grâce, entre autres, à la diffraction des neutrons, un renforcement de l'antiferromagnétisme 3d. Cela entraine la réduction du champ d'échange généré au site de l'ytterbium et conduit à la disparition de son magnétisme. Cela constitue donc un autre moyen de traverser l'instabilité magnétique de l'ytterbium. La dernière partie de ce mémoire ouvre la voie sur l'étude de nouveaux composés mettant en jeu une terre rare anormale associée à un sous réseau magnétique 3d. Les nombreux essais de synthèse sur les familles YbMn6-yCoyGe6-xSnx et CeMnGe1-xSix, ont permis de préciser les domaines de stabilité ainsi que les évolutions structurales, malgré la qualité moyenne des échantillons. La série YbMn6-yCoyGe6-xSnx pourrait être particulièrement prometteuse puisque susceptible d'associer deux points critiques au sein d'un même systèmeThe main part of this work completes and clarifies previous studies on the YbMn6Ge6-xSnx compounds and their Fe derivatives. A second exploratory part focuses on potentially promising new compounds in which an anomalous rare earth is associated with a magnetic 3d sublattice.The YbMn6Ge6-xSnx series shows signatures of quantum criticality at the Yb magnetic instability near x ~ 5.23. The first specific heat measurements performed in this work show the heavy fermion character of the alloys (γ > 100 mJ.K-2.mol-1). These measurements also corroborate the existence of a quantum critical point around x ~ 5.23, given the increase in the Sommerfeld coefficient γ (thus the effective mass) in the corresponding alloys, in agreement with theoretical predictions. In addition, XANES and XMCD measurements under pressure, using a low-gradient transmitter medium (He), show the beginning of a peak in the pressure dependence of the signals, similarly to what is observed in the composition dependence. A thermoelectric study has confirmed the importance of this technique for the study of heavy fermion systems, with thermoelectric response strongly dependent on the state of Yb. The Fe for Mn substitution in YbMn6-yFeyGe0.85Sn5.15 alloys (0.00 ≤ y ≤ 1.00) enhances 3d antiferromagnetism. This yields the reduction of the exchange field generated at the Yb site and induces the collapse of the magnetic character of Yb. This kind of substitution constitutes a new way to cross the Yb magnetic instability.In the last part, we have investigated new compounds involving an anomalous rare earth associated with a magnetic 3d sublattice. The numerous synthesis of YbMn6-yCoyGe6-xSnx and CeMnGe1-xSix compounds allow to specify the stability domains and the structural transitions in these series. However, the quality of the samples needs to be improved. The YbMn6-yCoyGe6-xSnx series might be very promising since it could associate two critical points within the same systems
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Tong, Jin. "Homo- and Mixed-valence [2 × 2] Grid Complexes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-8736-B.
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Erickson, Ann Shaklee. "Pairing mechanisms in superconductors with valence-skipping dopants /." May be available electronically:, 2009. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Londergan, Casey H. "Electron transfer and delocalization in mixed-valence complexes /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3091312.
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Viner, Russell. "The derivation of a valence forcefield for carbohydrates." Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329551.
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Zhao, Jianhong. "Syntheses and characterizations of a new valence-averaged mixed-valence diiron complex and a carbonyl derivative of the isovalent diiron complex." Scholarly Commons, 1995. https://scholarlycommons.pacific.edu/uop_etds/2292.
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The synthesis and characterization of a new mixed-valence bimetallic iron complex [Fe2(C20H36N8)(Cl)4]+ are reported. This binuclear species is assigned as a Robin and Day strongly coupled Class III mixed-valence species based on infrared spectroscopy, cyclic voltammetry, electronic spectroscopy, and X-ray photoelectron spectroscopy. The mixed-valence compound exhibits an intense NIR band at 883 nm with a molar absorptivity of 18000 M-1cm-1 and a band width at half-intensity of 2181 cm-1. This NIR band position Is solvent independent and HAM is calculated to be 5660 cm-1. A comproportionation constant of 1.7 x 1013 is obtained and this large value indicates that the mixed-valence species is stabilized by delocalization. The XPS results of the mixed-valence compound for the binding energies from Fe 2p3/2 region show only a single peak, indicating the unpaired electron is delocalized on the short time scale (10-17 sec) of XPS measurement.
Also a carbonyl derivative of the dimacrocycle bimetallic complex [Fe2(C20H36N8)(Cl)4]4+ has been isolated and its IR spectrum, electronic spectrum and electrochemical properties have been investigated.
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Charron, Catherine, and Catherine Charron. "Eau, patrimoine et communautés : le cas du Tribunal des eaux de Valence (Espagne)." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/37662.
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Ce mémoire étudie le fonctionnement et les processus de patrimonialisation du Tribunal des eaux de Valence (Espagne), ainsi que les mécanismes de la participation des communautés autonomes d'irrigants dans sa conservation, sa transmission et sa mise en valeur. Il s'intéresse aux perceptions des acteurs du milieu agricole, des juges (syndics) du Tribunal et des agriculteurs de la huerta valencienne, quant à la fonction sociale actuelle du Tribunal et à son rôle dans la sauvegarde des savoir-faire d'irrigations traditionnels. Le mémoire permet en outre de comprendre les impacts de la patrimonialisation de l'UNESCO sur le patrimoine culturel immatériel du point de vue des individus impliqués dans le Tribunal et du point de vue des agriculteurs sur le terrain.Ce mémoire étudie le fonctionnement et les processus de patrimonialisation du Tribunal des eaux de Valence (Espagne), ainsi que les mécanismes de la participation des communautés autonomes d'irrigants dans sa conservation, sa transmission et sa mise en valeur. Il s'intéresse aux perceptions des acteurs du milieu agricole, des juges (syndics) du Tribunal et des agriculteurs de la huerta valencienne, quant à la fonction sociale actuelle du Tribunal et à son rôle dans la sauvegarde des savoir-faire d'irrigations traditionnels. Le mémoire permet en outre de comprendre les impacts de la patrimonialisation de l'UNESCO sur le patrimoine culturel immatériel du point de vue des individus impliqués dans le Tribunal et du point de vue des agriculteurs sur le terrain.
This master thesis proposes an in-depth analysis of the functioning and heritage processes of the Valencia Water Tribunal (Spain), included in the Lift of the Intangible Cultural Heritage in 2009. In doing so, it provides new empirical evidence of the ways the participation of autonomous communities of irrigators impact its conservation, transmission and enhancement. The study details the actors’ perceptions of the role played by the judges of the Tribunal and the farmers in the huerta in safeguarding traditional irrigation knowhow and into current social functions of the Tribunal. One notable contribution this dissertation defends consists in better understanding the impacts of UNESCO's designation on intangible cultural heritage from the point of view of the actors (e.g. judges, farmers) involved in the Tribunal.
This master thesis proposes an in-depth analysis of the functioning and heritage processes of the Valencia Water Tribunal (Spain), included in the Lift of the Intangible Cultural Heritage in 2009. In doing so, it provides new empirical evidence of the ways the participation of autonomous communities of irrigators impact its conservation, transmission and enhancement. The study details the actors’ perceptions of the role played by the judges of the Tribunal and the farmers in the huerta in safeguarding traditional irrigation knowhow and into current social functions of the Tribunal. One notable contribution this dissertation defends consists in better understanding the impacts of UNESCO's designation on intangible cultural heritage from the point of view of the actors (e.g. judges, farmers) involved in the Tribunal.
Mi tesis se centra en el estudio del funcionamiento y del proceso de patrimonializacion del Tribunal de las Aguas de la vega de Valencia, nominado por la Lista del Patrimonio Cultural Inmaterial de la Humanidad de la UNESCO en 2009. También trata sobre los mecanismos de participación de las comunidades autonómicas de regantes de la huerta valenciana en su conservación, transmisión y mejora. Me intereso en las percepciones de los actores agrícolas, los síndicos del Tribunal y los regantes respecto alas funciones sociales actuales del Tribunal y su rol en la conservación, transmisión y mejora de los conocimientos tradicionales de riego. Mi tesis también permite de entender los impactos de la patrimonializacion por la UNESCO de un patrimonio cultural inmaterial desde el punto de vista de los actores implicados en la institución del Tribunal y desde el punto de vista de los agricultores.
Mi tesis se centra en el estudio del funcionamiento y del proceso de patrimonializacion del Tribunal de las Aguas de la vega de Valencia, nominado por la Lista del Patrimonio Cultural Inmaterial de la Humanidad de la UNESCO en 2009. También trata sobre los mecanismos de participación de las comunidades autonómicas de regantes de la huerta valenciana en su conservación, transmisión y mejora. Me intereso en las percepciones de los actores agrícolas, los síndicos del Tribunal y los regantes respecto alas funciones sociales actuales del Tribunal y su rol en la conservación, transmisión y mejora de los conocimientos tradicionales de riego. Mi tesis también permite de entender los impactos de la patrimonializacion por la UNESCO de un patrimonio cultural inmaterial desde el punto de vista de los actores implicados en la institución del Tribunal y desde el punto de vista de los agricultores.
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Martin, Franck. "Les Valenciens et leur langue régionale : approche sociolinguistique de l'identité de la communauté valencienne." Saint-Etienne, 2000. http://www.theses.fr/2000STET2060.
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Elément diacritique de première importance, la langue régionale de la communauté valencienne se situe depuis plusieurs décennies au coeur de diverses polémiques. Trois parties permettent de comprendre le sens, la portée et les enjeux de cette caractéristique. Une étude diachronique et synchronique de la configuration sociolinguistique valencienne (poids du valencien depuis l'émergence d'une conscience particulariste et décryptage de neuf avant-projets de statut d'autonomie) met en lumière le riche passé de Valence et le parcours mouvementé de sa langue régionale. Une deuxième partie est consacrée au valencien lors de l'autonomisation du territoire, processus rendu possible par la réorganisation politico-territoriale de l'Espagne en 1978. Après avoir étudié la place occupée par le valencien dans les débats autonomiques, nous analysons trois textes majeurs adoptés par Valence : la loi d'usage et d'enseignement du valencien, le plan triennal pour la promotion de l'usage du valencien dans la communauté valencienne, et le plan général de promotion de l'usage du valencien. En dernier lieu, nous présentons un bilan en demi-teinte de plus de quinze années de politique linguistique valencienne. En dépit de certaines insuffisances, le valencien parvient à s'imposer dans de nouveaux contextes communicationnels, grâce notamment aux efforts investis auprès de la jeunesse. Pour autant, soucieuse de sa « valencianité », la population convoque encore le passé plus souvent qu'elle n'interroge son devenir, ce qui freine l'élan de la communauté. Surtout, Valence continue de pâtir de l'influence du ! Secessionnisme linguistique, mouvement ascientifique qui utilise la langue régionale pour circonvenir la population et servir une idéologie rétrograde et xénophobe. Le « pacte linguistique » récemment adopté sera-t-il la clef, le sésame d'un lourd conflit, le premier pas vers une appréhension plus juste et plus raisonnée de l'un des principaux marqueurs de la « valencianité » ?
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Marchal, Michelle. "La valence du ligand du récepteur à la transferrine 1 (TfR1) détermine son routage intracellulaire." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS418.
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Le récepteur à la transferrine (TfR1) est un récepteur très bien conservé au cours de l’évolution qui permet l’entrée du fer (Fe) lié à la transferrine (Fe-Tf) dans les cellules. Une fois internalisé, le fer se détache de la Tf et est exporté dans le cytoplasme tandis que le complexe Tf/TfR1 est recyclé à la membrane plasmique. Le TfR1 est internalisé par un mécanisme clathrine dépendant et peut être soit recyclé à la membrane plasmique par la voie rapide, soit être dirigé vers le compartiment endosomal de recyclage (ERC). Une fois dans l’ERC, le TfR1 peut être soit recyclé à la membrane plasmique par la voie lente, soit être dirigé vers les lysosomes. De nombreuses protéines régulent le routage des protéines internalisées comme les protéines Rab. Il s’agit de petites GTPases impliquées dans les échanges moléculaires entre les différents compartiments cellulaires.Etant la principale voie d’entrée du fer dans la cellule,le TfR1 est exprimé par la plupart des cellules et est surexprimé par les cellules hautement prolifératives dont certaines cellules cancéreuses. Le TfR1 est très étudié comme cible thérapeutique dans le développement de nouvelles stratégies anti-cancéreuses. A24 est un anticorps murin anti-TfR1 dont l’action anti-proliférative et pro-apoptotique ont été démontrées dans plusieurs hémopathies malignes.Nous nous sommes demandés comment la fixation de A24 sur le TfR1 peut produire des effets différents de la fixation de la Fe-Tf. En générant un fragment Fab, nous avons d’abord démontré que le routage du TfR1 dépend de la valence de son ligand. Nous avons ensuite démontré que la fixation monovalente du TfR1 par la Fe-Tf et le Fab induisent son recyclage sans passer par l’ERC. Nous avons également démontré que la fixation divalente du TfR1 par A24 induit son routage depuis l’ERC vers les lysosomes par une voie dépendante de Rab12The transferrin receptor (TfR1) is a highly conserved receptor that allows the entry of iron (Fe) linked to transferrin (Fe-Tf) into cells. Once internalized, Fe separates from the Tf and is exported in the cytoplasm whereas the complex Tf/TfR1 is recycled to the cell membrane. TfR1 is internalized by a clathrin mediated endocytosis and can be either recycled to the cell membrane through the rapid pathway or be routed towards the endosomal recycling compartment (ERC). Once in the ERC, the TfR1 can be either recycled to the cell membrane through the slow pathway or be routed towards lysosomes. Many proteins regulates the routing of internalized proteins such as Rab proteins. They are small GTPases involved in molecular exchanges between the different cellular compartments.Being the main mode of entry of iron into cells, TfR1is expressed by almost every cells and is overexpressed by highly proliferative cells including some cancer cells. TfR1 is extensively studied as a therapeutic target for the development of new anti-cancer strategies. A24 is a murine anti-TfR1 whose anti-proliferative and pro-apoptotic roles were demonstrated in several hematological malignancies.We wondered how A24 binding on TfR1 can produce different effects from Fe-Tf binding. By the manufacturing of a Fab fragment, we first demonstrated that TfR1 fate depends on its ligand’s valency. We then demonstrated that the monovalent binding of TfR1 with Fe-Tf or the Fab leads to its recycling without going through the ERC. We also showed that the divalent binding of the TfR1 by A24 leads to its routing from the ERC to lysosomes through a Rab12 dependent pathway
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Édard, Florence. "Niveaux de valence inoccupes dans hcn, ch#3cn et ch#3nc : excitation en couche de valence; excitation en couche k; attachement electronique." Paris 6, 1991. http://www.theses.fr/1991PA066473.
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Les orbitales moleculaires de valence inoccupees, dont la connaissance est indispensable pour la comprehension de la reactivite chimique et de l'activite catalytique ont ete etudiees pour une serie de molecules possedant une triple liaison cn:hcn, ch#3cn et ch#3nc. Ces orbitales ont ete caracterisees grace a l'excitation des molecules par impact electronique dans plusieurs domaines d'energie. Les spectres de perte d'energie correspondant a l'excitation en couche de valence, obtenus pour une energie incidente comprise entre 20 et 100 ev, ont permis l'etude des composantes singulet et triplet des transitions pi-pi etoile et n-pi etoile et l'analyse des series de rydberg convergeant vers les premiers et deuxieme potentiels d'ionisation. Ces spectres ont ete compares aux spectres de perte d'energie correspondant a l'excitation en couche interne (c1s et n1s), obtenus pour des energies incidentes de 1 a 3 kev et mettant en jeu les transitions c1s pi etoile et n1s pi etoile. Enfin, a base energie incidente, une etude detaillee de l'excitation vibrationnelle, via les resonances de forme pi et sigma etoile, anions temporaires egalement observes en spectroscopie de transmission electronique, a ete realisee. L'energie des resonances de forme de basse energie de ces molecules a ainsi pu etre determinee. D'autre part, la selectivite des modes vibrationnels excites a ete analysee en envisageant un couplage vibronique entre les resonances pi et sigma etoile. De plus, l'etude complementaire de l'excitation vibrationnelle resonnante de cd#3cn montre l'existence d'un effet isotopique dans la section efficace d'excitation vibrationnelle de ch#3cn (cd#3cn) via la resonance sigma etoile. L'ensemble des resultats nous renseigne donc sur l'energie, la symetrie et la distribution spatiale des orbitales vacantes de basse energie des molecules hcn, ch#3cn et ch#3nc
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Corum, Aaron K. "Sixteen valence-electron species containing boron structural diversity abounds /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4303.
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Thesis (M.S.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (July 13, 2006) Includes bibliographical references.
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Rohr, Michaela [Verfasser]. "Masked processing of emotional information beyond valence / Michaela Rohr." Aachen : Shaker, 2014. http://d-nb.info/1060621762/34.
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Read, Nicholas. "Low temperature properties of models for mixed-valence compounds." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38140.
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Haynes, Matthew, and n/a. "Low Energy (e,2e) Studies of Inner Valence Ionization." Griffith University. Centre for Quantum Dynamics, 2002. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050902.142912.
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This thesis presents a series of electron impact ionization measurements on the gas phase targets of argon and krypton. The (e,2e) coincidence technique has been employed to measure the triple differential cross section (TDCS) using a new coincidence spectrometer designed to operate in the low energy regime (2 to 5 times the ionization energy) and in the coplanar geometry. The spectrometer is a conventional device utilizing a non-energy selected electron gun and two 1800 hemispherical electron analysers fitted with channel electron multipliers for detection of the outgoing electrons. A series of TDCS measurements were performed on the 3s inner-valence and 3p valence orbitals of argon employing coplanar asymmetric kinematics. Measurements for both orbitals were performed at an incident energy of 113.5 eV, ejected energies of 10, 7.5, 5 and 2 eV and a scattering angle of -15°. The energy of the scattered electron in each case was chosen to satis~' energy conservation and is dependent on the ionization energies of the different orbitals. The experimental cross sections are compared to theoretical TDCS calculations using the distorted wave Born approximation (DWBA) and variations of the DWBA in an attempt to investigate the role that post collisional interaction (PCI), polarization and electron exchange play in describing the TDCS in the low energy regime. To further extend this analysis, a series of TDCS measurements were performed on the 3s and 4s. orbitals of argon and krypton, respectively, employing coplanar symmetric kinematics. Measurements were performed for the 3s orbital at outgoing energies of 50, 20, 10 and 4eV and for the 4s orbital at outgoing energies of 85, 50, 20 and 10 eV. The kinematics were chosen to coincide with several of the (e,2e) measurements made in the same geometry on the 3p orbital of argon by Rouvellou et al (1998). The experimental results were again compared to a DWBA calculation and similar variations to those employed for the asymmetric measurements.
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Pschirer, David M. "Electrochemical uranium valence control in centrifugal solvent extraction contractors." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/12995.
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Zhao, Xiaodong. "Studies of extended cyanines and related mixed valence compounds." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/28001.
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Clarke, John Nicholas. "Applications of modern valence bond theory to small molecules." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260246.
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Wilmhurst, Alan Stephen. "Complex harmonic mappings and the valence of harmonic polynomials." Thesis, University of York, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259748.
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Whittle, Karl R. "Redox and mixed valence in some solid state systems." Thesis, Open University, 1998. http://oro.open.ac.uk/57915/.
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Pališaitis, Justinas. "Valence Electron Energy Loss Spectroscopy of III-Nitride Semiconductors." Doctoral thesis, Linköpings universitet, Tunnfilmsfysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-85907.
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This doctorate thesis covers both experimental and theoretical investigations of the optical responses of the group III-nitrides (AlN, GaN, InN) and their ternary alloys. The goal of this research has been to explore the usefulness of valence electron energy loss spectroscopy (VEELS) for materials characterization of group III-nitride semiconductors at the nanoscale. The experiments are based on the evaluation of the bulk plasmon characteristics in the low energy loss part of the EEL spectrum since it is highly dependent on the material’s composition and strain. This method offers advantages as being fast, reliable, and sensitive. VEELS characterization results were corroborated with other experimental methods like X-ray diffraction and Rutherford backscattering spectrometry as well as full-potential calculations (Wien2k). Investigated III-nitride structures were grown using magnetron sputtering epitaxy and metal organic chemical vapor deposition techniques. Initially, it was demonstrated that EELS in the valence region is a powerful method for a fast compositional analysis of the Al1-xInxN (0≤x≤1) system. The bulk plasmon energy follows a linear relation with respect to the lattice parameter and composition in Al1-xInxN layers. Furthermore, the effect of strain on valence EELS was investigated. It was experimentally determined that the AlN bulk plasmon peak experiences a shift of 0.156 eV per 1% volume change at constant composition. The experimental results were corroborated by full-potential calculations, which showed that the bulk plasmon peak position varies nearly linearly with the unit-cell volume, at least up to 3% volume change. Employing the bulk plasmon energy loss, compositional characterization was also applied to confined structures, such as nanorods and quantum wells (QWs). Compositional profiling of spontaneously formed AlInN nanorods with varying In concentration was realized in cross-sectional and plan-view geometries. It was established that the structures exhibit a core-shell structure, where the In concentration in the core is higher than in the shell. The growth of InGaN/GaN multiple QWs with respect to composition and interface homogeneities was investigated. It was found that at certain compositions and thicknesses of QWs, where phase separation does not occur due to spinodal decomposition. Instead, QWs develop quantum dot like features inside the well as a consequence of Stranski-Krastanov-type growth mode, and delayed In incorporation into the structure. The thermal stability and degradation mechanisms of Al1-xInxN (0≤x≤1) films with different In contents, stacked in a multilayer sample, and different periodicity Al1-xInxN/AlN multilayer films, was investigated by performing a thermal annealing in combination with VEELS mapping in-situ. It was concluded that the In content in the Al1-xInxN layer determines the thermal stability and decomposition path. Finally, the phase separation by spinodal decomposition of different periodicity AlInN/AlN layers, with a starting composition inside the miscibility gap, was explored.
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Maillard, Agnès. "Structure et riftogenese du golfe de valence (mediterranee occidentale)." Paris 6, 1993. http://www.theses.fr/1993PA066163.
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Le rift de valence s'est forme au neogene durant l'ouverture de la mediterranee occidentale. La structure de son substratum, recouverte en grande partie par des epanchements volcaniques, indique une faible extension superficielle mais revele que l'ouverture s'est effectuee le long d'accidents transversaux nw-se decoupant le bassin de valence en plusieurs compartiments, avec un amincissement crustal augmentant vers le ne. Des modelisations a partir de donnees de subsidence et de flux thermique, (contraintes par l'etude stratigraphique et structurale), mettent en evidence l'evolution polyphasee du golfe, et un rejeu recent de plus en plus important vers le sw ou une anomalie thermique peut s'expliquer par un amincissement lithospherique
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Housley, Meghan K. "The Positivity-Cues-Familiarity Effect and Initial Stimulus Valence." Miami University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=miami1185554049.
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Granados, Samayoa Javier Andre. "On the Relation between Valence Weighting and Self-Regulation." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1493828051570488.
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