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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
501

Mechanistic study on tertiary phosphine complexes of ruthenium as olefin metathesis catalysts.

Oosthuizen, Sharon 15 May 2008 (has links)
Ruthenium carbene complexes, with the general structure, [LL’Ru=CHR], are commonly known as Grubbs type catalysts, named after the discoverer of these metathesis catalysts. The discovery was quite revolutionary, since the catalysts proved to be easy to handle, tolerant towards various functional groups and more stable with regard to air and water than previous transition metal catalysts. Another important advantage was that all types of olefin metathesis reactions could be initiated without the help of co-catalysts or promoters. Today Grubbs type catalysts find wide application in especially organic and synthetic chemistry. A well-known example is the SHOP-process which produces long chain -olefins, while other important applications include the synthesis of macro-cyclic and cyclic olefins. The current study involved experimental and theoretical work to investigate various aspects comprising synthetic procedures, reactivity, kinetics, geometry and electronic properties of the complexes. Results are discussed briefly in the following paragraphs. The first aim of the project was to synthesise a Grubbs type catalyst. Initial efforts were focused on the preparation of a first generation catalyst through various methods. This included modifying the reported method for the synthesis of [(PPh3)2Cl2Ru=CH-CH=CMe2] to yield [(PPh2Cy)2Cl2Ru=CHCH= CMe2] instead; a phosphine exchange reaction with the complex [(PPh3)2Cl2Ru=CH-CH=CMe2] and free phosphine PPh2Cy; and utilising the analogue arsine ligand, AsPh3, to synthesise [(AsPh3)2Cl2Ru=CHCH=CMe2]; but unfortunately no success was achieved. However, it was possible to synthesise a novel second generation Grubbs type catalyst, [(IMesH2)(PPh2Cy)Cl2Ru=CHPh], through the phosphine exchange reaction of [(IMesH2)(NC5H5)2Cl2Ru=CHPh] and PPh2Cy. The new complex was tested in kinetic reaction studies and phosphine exchange reactions. Results showed that [(IMesH2)(PPh2Cy)Cl2Ru=CHPh] was catalytically active for the ring closing metathesis of commercial diethyl diallylmalonate. The reaction was first order with regard to the olefin, contrary to the second order kinetic results reported for similar reactions catalysed by first generation Grubbs catalysts. The phosphine exchange reactions were very successful and a rate constant could be determined. The rate constant was independent of the free phosphine concentration and activation parameters had relatively large, positive values; results indicative of a dissociative mechanism. These findings are in correlation with literature reports. A kinetic investigation was done on the catalyst-olefin coordination involving the functionalized olefins vinyl acetate, allyl acetate and allyl cyanide; and the first generation Grubbs catalyst, [(PCy3)2Cl2Ru=CHPh]. A two-step rate law, similar to an interchange mechanism, was determined. Phobcat, [(PhobCy)2Cl2Ru=CHPh], is modified first generation Grubbs type catalyst with rigid bicyclic phosphine rings which was recently developed by the Sasol Homogeneous Metathesis Group. In the current study Phobcat was compared to Grubbs1-PCy3 in the cross metathesis reaction of 1-octene. Results showed that Phobcat was up to 60% more active and had a 5 hour longer lifetime than Grubbs 1-PCy3. Theoretical studies were done on the three functionalized olefins of the earlier experimental study to gain fundamental understanding of steric and electronic influences on these catalyst-olefin systems. Without exception, coordination via the heteroatom of the olefin was significantly more favourable than coordination via the double bond functionality. This result indicates that metathesis of these olefins is highly unlikely, since the stable heteroatom coordination will suppress the parallel Ru=C/C=C interaction which is compulsory for the metathesis reaction. Orbital studies highlighted the difference between coordination of acetate and cyanide, but no trend of an electronic nature could be recognised. / Prof. A. Roodt
502

The causal role of appraisal biases upon negative repetitive thinking and emotional reactivity

Williams, Kate Victoria January 2016 (has links)
Attributional style is hypothesised to causally contribute to depression vulnerability through influencing both emotional response and rumination following life events. Consistent with this hypothesis, Peters et al. (2011) found that training individuals towards a pessimistic attributional style, characterised by internal-stable attributions for negative events and external-unstable attributions for positive events, resulted in greater negative mood and emotional reactivity to perceived failure, relative to training a resilient attributional style characterized by the reverse pattern of attributions. To date, however, the relative contribution of the internal-external and stable-unstable dimensions, their interaction, and their application to positive or negative events upon influencing emotional response and, by theoretical extension, risk for depression, remains unresolved. To resolve this question, 80 participants received training manipulating attributional style along four dimensions (i.e., internal versus external attributions for negative events; internal versus external attributions for positive events; stable versus unstable attributions for negative events; stable versus unstable attributions for positive events) in a 24 orthogonal factorial design. Participants then completed a perceived failure induction task. Measures of emotion and state rumination were completed pre-manipulation, post- manipulation, and post-induction. The internality dimension for positive and, separately, negative events influenced both immediate emotional response and emotional reactivity. Stable attributions for negative events increased negative emotional response and moderated the effect of internal attributions for negative events: internal attributions to negative resulted in greater emotional reactivity relative to external attributions, but only in the context of stable attributions for negative events. Both internal and stable dimensions also had independent effects. These findings identifying the active components driving the effect of attributional style upon emotional reactivity suggest slight revisions and refinements to attribution models of depression vulnerability. Furthermore, it provides further evidence that attributional style can be modified and furthers understanding of how CBM-attribution training could be developed as a potential intervention for the treatment of depression.
503

Contribution à la modélisation d’un gazeifieur de biomasse : application à un gazeifieur allothermique solaire pour la production de gaz de synthèse / Modeling of biomass gasification : investigation of a packed-bed solar reactor for the steam gasification

Freysz, Valerian 23 September 2016 (has links)
Ce travail porte sur la modélisation de gazéification de la biomasse dans un réacteur solaire à lit fixe. Nous avons développé et validé différents modules pour la résolution des problèmes physiques associés à de tels gazéifieurs (volumes finis, équilibre thermodynamique, facteur de forme, radiosité, évolution du maillage, etc.). Le réacteur est ensuite modélisé et confronté à des mesures expérimentales pour sa validation. Ces résultats nous laissent supposer que, pour les conditions opératoires rencontrées dans ce réacteur, l’évolution de la vitesse de chauffage et du taux de centre sont des facteurs d’influence importants de la cinétique pour le bois de hêtre. Une étude du réacteur en supposant que la réaction atteint l’équilibre thermodynamique est ensuite conduite et montre que cette approche doit être employée avec précaution pour le domaine de température étudié. Une étude paramétrique concernant la mise en place d’un échangeur air-air entre le gaz de sortie et le gaz d’entrée est proposée. Elle nous montre que l’ajout d’un gaz inerte peut être intéressant d’un point de vue énergétique dans de telles conditions. Enfin, un absorbeur solaire adapté au gazéifieur est ensuite modélisé et validé afin de pouvoir évaluer la sensibilité du système complet. / This work focuses on the modeling of biomass gasification in a solar fixed bed reactor. We developed and validated different modules to compute physical problems associated with such gasifier (finite volume, thermodynamic equilibrium, view factor, radiosity, evolution of the mesh, etc.). The reactor is then modeled, and results are compared to experimental measurements for its validation. These results suggest that for the operating conditions encountered in this reactor, the evolution of the heating rate and the ash concentration may influence the kinetics of the beech wood gasification. A study of the reactor by assuming thermodynamic equilibrium is conducted and shows that this approach should be used with caution for the studied temperature range. Parametric study of an air-air exchanger between the output and input gas is proposed. It shows that the addition of an inert gas can be interesting from an energy point of view in such conditions. Finally, a solar absorber suited to the reactor is modeled and validated in order to assess the sensitivity of the complete system.
504

Understanding the dynamic nature of well-being: a multilevel SEM framework to capture intra- and inter-individual associations across multiple timescales and levels of analysis

Rush, Jonathan 18 May 2018 (has links)
The study of well-being has a long history of investigation from a nomothetic (between-person) perspective that aimed to understand characteristic levels of well-being and individual difference variables that account for stable differences across people. Recent investigations have demonstrated that levels of well-being have the capacity to rapidly fluctuate within people over short intervals and also exhibit slower changes over longer intervals, highlighting the importance of considering the ideographic (within-person) nature of well-being. The aim of this dissertation was to help build on such within-person understanding by demonstrating how theories of well-being may be empirically evaluated using innovative research designs (e.g., intensive repeated measurement designs) and analytic techniques (e.g., multilevel structural equation models [MSEM]) that can fully capture the complexity and dynamic nature of well-being. Three distinct research studies employing intensive repeated measurement designs and an MSEM analytic framework addressed a variety of research questions concerning intra- and inter-individual predictors of well-being. Study one (Chapter 2) simultaneously examined the multilevel moderation and mediation effects of cognitive interference on stress reactivity estimated in a 14-day daily diary design. Study two (Chapter 3) utilized measurement burst data from a large U.S. sample of adults, assessed across multiple time-scales, to examine long-term changes in short-term within-person associations. Random within-person slopes were specified as exogenous predictor variables of individual differences in global levels of psychological well-being. Study three (Chapter 4) used simulation data to examine the conditions where specifying within-person measurement scales as latent variables compared to unit-weighted composite scores optimized detection of within-person effects. This dissertation demonstrates the importance of innovative design and analysis to appropriately model and understand the complex, dynamic associations that operate within and across individuals in predicting their experiences of well-being. / Graduate / 2019-05-14
505

Design, synthèse et application de nouveaux catalyseurs d'or (I) et d'or (III) / Design, synthesis and application of new gold(I) and gold(III) catalysts

Hueber, Damien 20 May 2015 (has links)
En synthèse organique, la recherche de nouveaux catalyseurs est un point crucial pour améliorer les conditions réactionnelles et découvrir de nouvelles réactions, particulièrement en chimie de l’or. Pour contribuer à ce développement, nous nous sommes intéressés à la nature du contre-ion, dont dépend la réactivité du catalyseur d’or, avec les polyoxométallates. Ces polyanions, de par leur nature intrinsèque, ont permis d’obtenir de nouveaux catalyseurs efficaces, polyvalents, multi-fonctionnels et hétérogènes, et applicables à un grand nombre de réactions catalysées à l’or.Nous avons aussi étudié un autre paramètre essentiel de la composition d’un catalyseur d’or : le ligand. Notre intérêt s’est porté sur les ligands carbènes N-hétérocycliques (NHC), dont la modularité de leurs propriétés électronique et stérique confère à l’or d’importantes activités. Nous avons ainsi développé différents types de NHC, en les fonctionnalisant pour les rendre acteurs de la réactivité, ou encore en leur attribuant de nouveaux groupements très encombrant pour influencer la réactivité et la sélectivité. / In organic synthesis, the research of new catalysts is an essential issue to improve reactional conditions and to discover new reactions, especially in gold chemistry. To contribute to this development, we were interested in the nature of the counter-ion, which impact the reactivity of the gold catalyst, with the polyoxometalates. These polyanions, thanks to their nature, allowed to obtain new efficient, polyvalent, multi-functional and heterogeneous catalysts, which could be applied to a wide scope of gold catalyzed reactions.We also studied another essential parameter of the composition of gold catalysts: the ligand. We focused our attention on the N-heterocyclic carbenes (NHC), whose modularity of their electronic and steric properties confer important activities to gold catalysts. Thus we developed different kind of NHC, by functionalizing them so they can be involved in the reactivity, or by attributing them very bulky groups to influence the reactivity and selectivity.
506

Etude théorique des nanoparticules à base de Palladium pour la réaction d’hydrogénation sélective des alcynes / Theoretical study of palladium-based nanoparticles for the selective hydrogenation reaction of alkynes

Gantassi, Oussama 13 December 2016 (has links)
Les catalyseurs à base de nanoparticules de Pd sont largement utilisés dans l’industrie des oléfines. Ceux-ci permettent d’hydrogéner les sous produits de la réaction tel que l'acétylène (C2H2) qui peut empoisonner et désactiver le catalyseur. Toutefois, le Pd, bien que très actif pour la réaction d’hydrogénation, est peu sélectif. Ainsi, l'acétylène et l'éthylène (qui sont des hydrocarbures insaturés) interagissant avec le Pd peuvent être hydrogénés en éthane (C2H6), qui est un produit toxique. Ainsi, un effort considérable est consacré à l’amélioration de la sélectivité des catalyseurs à base de Pd. Ce travail de thèse rentre dans ce cadre. Il consiste à décrire à l’échelle moléculaire les sites actifs du catalyseur au Pd et à identifier les mécanismes réactionnels qui peuvent avoir lieu. Le but étant de comprendre comment les propriétés intrinsèques du catalyseur au Pd varient avec la taille, la forme, les supports d'oxyde et l'incorporation d'additifs métalliques, afin d'améliorer leur sélectivité. L'hydrogénation de l'éthylène en acétylène est étudiée en tant que réaction prototype.Pour atteindre ces objectifs, la Théorie de la Fonctionnelle de la Densité, via une approche périodique à l’aide du code VASP, a été appliquée à plusieurs modèles de catalyseurs de Pd. Ces modèles constitués de nanoparticules de quelques atomes (Pdn, n=1,2,..,7, 13, and 55) et de surface semi-infinie de Pd(111) ont permis d’étudier l’effet de la forme et de la taille sur les propriétés magnétiques et sur la réactivité du Pd. L’étude de la réactivité a concerné essentiellement les mécanismes d’adsorption de C2H2 et C2H4. Ensuite, étant donné que, dans les conditions réelles, les catalyseurs sont stabilisés sur des supports oxyde de type TiO2, la surface de ce dernier a été considérée dans nos modèles. Ainsi, les propriétés électroniques et la réactivité des nanoparticules libres et supportées ont pu être comparées pour mettre en évidence l’effet du support. Enfin, dans le but d’améliorer la sélectivité du Pd, et de prédire un catalyseur performant, des additifs de type métaux de transition (M avec M=Au, Ag, Cu, Co, Ni, Fe etc..) ont été considérés. En effet, en misant sur les effets de synergie qui peuvent se produire pour des couples bimétalliques grâce aux modifications des densités électroniques, il a été possible de prédire des combinaisons de métaux (PdM) dont les propriétés électroniques sont différentes de celles des éléments pris séparément. L’étude des chemins réactionnel et l’identification des barrières d’activation semblent indiquer que les systèmes Pd-Fe et Pd-Co sont des candidats intéressants. / The catalysts based on Pd nanoparticles are widely used in the olefin purification industry. This allows to hydrogenate the by-products of the reaction such as acetylene (C2H2), which can poison and deactivate the catalyst. Although Pd-based catalysts are very active for the hydrogenation reaction, they have a low selectivity. Thus, acetylene and ethylene (which are unsaturated hydrocarbons) interacting with the Pd-catalysts may be hydrogenated to ethane (C2H6), which is a toxic product. Considerable effort is devoted to improve the selectivity of catalysts based on Pd. The present thesis is within this framework. It describes at the molecular level the active sites of Pd-model catalysts and identifies the reaction mechanisms. The goal is to understand how the intrinsic properties of Pd catalyst vary with different size and shape, oxide supports and incorporation of metal additives, in order to improve their selectivity. The hydrogenation of ethylene to acetylene is studied as a prototype reaction. To achieve the goal, periodic Density Functional Theory approach, as implemented in the VASP code, was applied to several Pd-catalysts models. These models include nanoparticles of few atoms (Pdn, n=1,..,7, 13, and 55) and semi-infinite Pd surface (111). They were used to study the effect of the shape and size on the magnetic and electronic properties, and their influence on the reaction pathways. The first step in the reaction mechanism is the adsorption of C2H2 and C2H4. Therefore, the adsorption mechanism was also examined for various magnetic isomers of Pdn structures. Because in the real conditions, the catalysts are often stabilized on TiO2 oxide supports, the surface of the latter was considered in our models. Thus, the electronic properties and reactivity of free and supported Pd-nanoparticles could be compared to reveal the effect of the support. Finally, in order to improve the selectivity of Pd, and predict an effective catalyst, transition metals additives (M = Au, Ag, Cu, Co, Ni, Fe etc...) have been considered. Indeed, building on the synergies that can occur for bimetallic couples through changes in electron densities, it was possible to predict combinations of metals (PdM) whose electronic properties are different from those of their monometalic counterpart. The study of reaction pathways and identification of activation barriers suggest that Pd-Fe and Pd-Co systems are the best candidates.
507

Reaktivita a tolerance k frustraci z pohledu psychologie u odsouzených pachatelů trestné činnosti / Reactivity and tolerence to frustration from the perspective of psychology for convicted criminal offenders

Okrouhlická, Kateřina January 2015 (has links)
The thesis deals with reactivity in response to a frustrating situation for convicted offenders. The main issue in the theoretical element is reactivity; or rather the behaviour and manifestation of reactions in the moment when an individual gets into stressful situations, is impeded or blocked in achieving their target. The definition of frustration is an equally important area, which, in the thesis is initially described from the perspective of classic theorists, and then the various ways how we examine and diagnose frustration. The last and equally important chapter consists of the offender's personality, which is defined in the context of the aforementioned frustration and reactivity. The aim of the empirical component is to obtain quantitative data on the most frequent reactions among criminal offenders in the moment before they face the obstacle that is blocking their achievement of goals or satisfaction. The research sample was composed of 69 convicted criminal offenders from remand prisons Pankrác, Hradec Kralové and prison Plzeň. The Picture Rosenzweig frustration method was used to examine the reactivity as a result of frustration. Four hypothesis was determined and only one hypothesis was confirmed. Extragression, outside oriented response, is the most frequently response in comparison...
508

確率論的手法による炉心解析に関する研究

長家, 康展 26 November 2012 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第17234号 / 工博第3661号 / 新制||工||1556(附属図書館) / 29980 / 京都大学大学院工学研究科原子核工学専攻 / (主査)教授 中島 健, 教授 福山 淳, 准教授 山本 俊弘 / 学位規則第4条第1項該当
509

Reaktivita a vlastnosti analog trifosfátu / Reactivity and properties of triphosphate analogues

Šrein, Jakub January 2017 (has links)
Reactions leading to cyclization on methylene bridges in PCPCP structure motif were investigated. It was found, that these reactions result in number of various isomers. Some of these isomers were characterized by NMR and MS spectroscopy, but none was isolated. Further, acid-base properties of bis(methylenephosphonato)phosphineic acid were investigated. Formation of complexes was studied with lithium(I), calcium(II), copper(II) and zinc(II) cations. Furthermore, interaction between bis(methylenephosphonato)phosphinic acid and ethylenediamine was investigated by NMR and potentiometric titration. The results show formation of H-bond-based adducts.
510

Beyond the gap of pressure : XPS studies of interfaces at near ambient pressures / Au-delà du gap de pression : étude par XPS d'interfaces à des pressions proches de l'ambiant

Tissot, Héloïse 23 September 2014 (has links)
Dans de nombreux procédés technologiques, tels que la fabrication de matériaux pour la microélectronique, l’étude des réactions chimiques à une électrode, ou encore la catalyse… L’interface entre la surface d’un solide ou d’un liquide avec un liquide ou une phase gaz joue un rôle fondamental. De façon analogue, les sciences de l’environnement ainsi que celles du vivant intègrent dans leurs modèles la réactivité aux interfaces solide/ liquide ou liquide/ gaz.L’XPS est une technique parfaitement adaptée à l’étude des interfaces et a été largement utilisée pour l’analyse des surfaces de solides. Le principal avantage de l’XPS est sa grande sensibilité aux surfaces. En effet, en raison du faible libre parcours moyen des électrons dans un solide, uniquement les photoélectrons provenant de l’extrême surface (1 – 10 nm) peuvent échapper à celle-ci. Cependant, l’XPS est traditionnellement utilisée dans des conditions d’ultravide (UHV) et cela pour deux raisons. La première est que les analyseurs d’électrons sont construits pour fonctionner en UHV. La seconde est que les électrons doivent pouvoir atteindre l’analyseur, or leur libre parcours moyen est faible dans un gaz à haute pression. Par exemple, à une pression de 1 mbar, des électrons possédant une énergie de 100 eV vont parcourir 1 mm alors qu’ en UHV ils pourront atteindre jusqu’ à 105 m.Dans le but de rendre possible l’utilisation de l’XPS à des pressions plus élevées, quelques groupes autour du monde, dont le groupe de Berkeley (sous la direction de M. Salmeron at de H. Bluhm) et celui du Fritz Haber Institute à Berlin, ont élaborés un équipement permettant d’atteindre des pressions proche de l’ambiant (5 mbar). La construction d’un analyseur d’électron capable de fonctionner à des pressions de l’ordre du mbar, c’est-à-dire à des pressions 7 ordres de grandeur supérieures à l’UHV, a été une avancée à la fois conceptuelle et technologique. Un système de pompage différentiel permet de maintenir l’échantillon dans des conditions dites environnementales tout en maximisant le libre parcours moyen des électrons de façon à ce qu’ils atteignent l’analyseur. De plus, des tensions sont appliquées à des lentilles électrostatiques dans le but d’accélérer et de focaliser ces électrons.Un système similaire (Near Ambient Pressure XPS, NAP-XPS) a été installé sur la ligne TEMPO du synchrotron Soleil en février 2013, le premier temps de faisceau ayant eu lieu au mois de mai suivant. Durant ma thèse, deux projets différents ont été développés, tous les deux liés à l’étude d’interfaces avec l’utilisation de la NAP-XPS.Le premier projet traite des procédés utilisés en micro-electronique pour déposer de fines couches d’oxydes : le dépôt chimique en phase vapeur (CVD) et la déposition de couches atomiques (ALD). En particulier, des molécules de la famille des silanes sont utilisées pour fonctionnaliser des surfaces d’oxyde de silicium ou comme précurseur, combiné à un agent oxydant comme l’eau pour le dépôt de films mince d’oxyde de silicium. Cependant, les mécanismes réactionnels des silanes sur les surfaces de silicium n’ont jamais été étudiés par des techniques telles que la microscopie a effet tunnel (STM) ou l’XPS et l’on sait peu de choses concernant leur mécanisme de dissociation et l’adsorption des divers fragments sur la surface. / In many processes or technological objects, such as coating deposition, advanced material processing for electronics, magnetic or optical devices, electrochemical processes at an electrode, sensors and catalysis, etc. the interface between a surface of a solid and a liquid or a gas phase, plays a prominent role. Analogously, environmental sciences and sciences of the Living integrate into their models chemical reactions taking place at solid/liquid or liquid/gas interfaces.XPS is a powerful technique for interface analysis and has been widely use in the case of solid surface. The main advantage of XPS is its sensitivity to the material surface. Indeed, due to the low electron mean free path of electrons in a solid, only the photoelectrons at the extreme outer surface (1-10 nm) can escape the sample. However, XPS has traditionally been conducted under ultra-high vacuum (UHV) conditions. UHV conditions are utilized for two reasons. First, the analyzers are designed to work under UHV conditions. Second, the electrons must reach the detector and their mean free path is short at high pressures. For example at a pressure of 1 mbar, 100 eV electrons will travel 1 mm while under UHV conditions, the mean free path increases to 105 m. UHV chambers (10-10 mbar) help maximize the mean free path so that a high number of electrons will reach the detector/analyzer and the signal/noise ratio will increase making it possible to analyze the spectrum produced. This constraint makes UHV the standard environment of X-ray Photoelectron Spectroscopy (XPS) experiments.In order to make possible the use of XPS on a larger pressure range, a few groups around the world have designed photoemission equipment that can be operated under ambient pressure (up to 5 mbar). The Berkeley group (M. Salmeron LBNL-Materials Sciences Division, H. Bluhm LBNL-Chemical Sciences Division), who pioneered this field, has two such setups installed at the Advanced Light Source. The Fritz Haber Institute has built a high pressure XPS based on the Berkeley prototype, installed at BESSY synchrotron (Berlin), since 2002. The building of Ambient Pressure XPS (APXPS) analyzers of the Berkeley type, able to be operated at pressures in the range of 1 mbar, about 7 orders of magnitude higher than the pressure limit of conventional UHV equipment is both a technological and conceptual breakthrough. Differential pumping stages allow the sample to remain at environmental pressures, while maximizing the mean free path of emitted electrons, so they can reach the detector. Additionally, voltages are applied to electrostatic lenses in the unit to accelerate and focus the electrons onto the focal plane of the electron energy analyzer. A similar system Near-Ambient Pressure XPS, NAP-XPS), described in details in chapter 1, was delivered in December 2012 and installed at TEMPO beamline in February 2013. The first beamtime occurred in May 2013. During my thesis that started in October 2011 two different projects were developed, both related to interface analysis using the NAP-XPS instrument.

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