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141	Corrosion Study Of Interstitially Hardened SS 316L AND IN718 In Simulated Light Water Reactor Conditions Niu, Wei January 2017 (has links) No description available. Chemical Engineering Materials Science Nuclear Engineering SS 316L IN 718 Interstitially hardening Boiling water reactor normal water chemistry hydrogen water chemistry focused ion beam transmission electron spectroscopy Transgranular stress corrosion cracking
142	Structure and Dynamics of Core-Excited Species Travnikova, Oksana January 2008 (has links) <p>In this thesis we have performed core-electron spectroscopy studies of gas phase molecular systems starting with smaller diatomic, continuing with triatomic and extending our research to more complex polyatomic ones. We can subdivide the results presented here into two categories: the first one focusing on electronic fine structure and effect of the chemical bonds on molecular core-levels and the other one dealing with nuclear dynamics induced by creation of a core hole. In our research we have mostly used synchrotron radiation based techniques such as X-ray Photoelectron (XPS), X-ray Absorption (XAS), normal and Resonant Auger (AES and RAS, respectively) and Energy-Selected Auger Electron PhotoIon COincidence (ES-AEPICO) spectroscopies.</p><p>We have demonstrated that resonant Auger spectroscopy can be used to aid interpretation of the features observed in XAS for Rydberg structures in the case of Cl<sub>2</sub> and C1s<sup>−1</sup>π*<sup>1</sup> states of allene molecules. The combined use of high-resolution spectroscopy with <i>ab initio</i> calculations can help the interpretation of strongly overlapped spectral features and disentangle their complex profiles. This approach enabled us to determine the differences in the lifetimes for core-hole 2p sublevels of Cl<sub>2</sub> which are caused by the presence of the chemical bond. We have shown that contribution in terms of the Mulliken population of valence molecular orbitals is a determining factor for resonant enhancement of different final states and fragmentation patterns reached after resonant Auger decays in N<sub>2</sub>O.</p><p>We have also performed a systematic study of the dependence of the C1s resonant Auger kinetic energies on the presence of different substituents in CH<sub>3</sub>X compounds. For the first time we have studied possible isomerization reaction induced by core excitation of acetylacetone. We could observe a new spectral feature in the resonant Auger decay spectra which we interpreted as a signature of core-excitation-induced keto-enol tautomerism.</p> Physics Synchrotron radiation X-ray Photoelectron Spectroscopy (XPS) X-ray Absorption Spectroscopy (XAS) Resonant Auger Spectroscopy (RAS) Auger Electron Spectroscopy (AES) core excitation core ionization linear free energy relationships (LFER) molecular-field splitting substituent effects nuclear dynamics isomerization Cl2 N2O methane derivatives allene acetylacetone Fysik
143	Photoelectron Spectroscopy on Atoms, Molecules and Clusters : The Geometric and Electronic Structure Studied by Synchrotron Radiation and Lasers Rander, Torbjörn January 2007 (has links) <p>Atoms, molecules and clusters all constitute building blocks of macroscopic matter. Therefore, understanding the electronic and geometrical properties of such systems is the key to understanding the properties of solid state objects.</p><p>In this thesis, some atomic, molecular and cluster systems (clusters of O<sub>2</sub>, CH<sub>3</sub>Br, Ar/O<sub>2</sub>, Ar/Xe and Ar/Kr; dimers of Na; Na and K atoms) have been investigated using synchrotron radiation, and in the two last instances, laser light. We have performed x-ray photoelectron spectroscopy (XPS) on all of these systems. We have also applied ultraviolet photoelectron spectroscopy (UPS), resonant Auger spectroscopy (RAS) and near-edge x-ray absorption spectroscopy (NEXAFS) to study many of the systems. Calculations using <i>ab initio</i> methods, namely density functional theory (DFT) and Møller-Plesset perturbation theory (MP), were employed for electronic structure calculations. The geometrical structure was studied using a combination of <i>ab initio</i> and molecular dynamics (MD) methods.</p><p>Results on the dissociation behavior of CH<sub>3</sub>Br and O<sub>2</sub> molecules in clusters are presented. The dissociation of the Na<sub>2</sub> molecule has been characterized and the molecular field splitting of the Na 2<i>p</i> level in the dimer has been measured. The molecular field splitting of the CH<sub>3</sub>Br 3<i>d</i> level has been measured and the structure of CH<sub>3</sub>Br clusters has been determined to be similar to the structure of the bulk solid. The diffusion behavior of O<sub>2</sub>, Kr and Xe on large Ar clusters, as a function of doping rate, has been investigated. The shake-down process has been observed from excited states of Na and K. Laser excited Na atoms have been shown to be magnetically aligned. The shake-down process was used to characterize the origin of various final states that can be observed in the spectrum of ground-state K.</p> Atomic and molecular physics Free clusters Electron spectroscopy Doped clusters Laser excitation Alkali metals Electronic structure Geometric structure X-ray photoelectron spectroscopy (XPS) Resonant Auger spectroscopy (RAS) Detuning Ultra-fast dissociation (UFD) Sodium Potassium Oxygen Bromomethane Argon Xenon Krypton Molecular field splitting Core hole lifetime Core excitation Atom- och molekylfysik
144	A Treatise on the Geometric and Electronic Structure of Clusters : Investigated by Synchrotron Radiation Based Electron Spectroscopies Lindblad, Andreas January 2008 (has links) <p>Clusters are finite ensembles of atoms or molecules with sizes in the nanometer regime (<i>i.e.</i> nanoparticles). This thesis present results on the geometric and electronic structure of homogeneous and heterogeneous combinations of atoms and molecules. The systems have been studied with synchrotron radiation and valence, core and Auger electron spectroscopic techniques.</p><p>The first theme of the thesis is that of mixed clusters. It is shown that by varying the cluster production technique both structures that are close to that predicted by equilibrium considerations can be attained as well as far from equilibrium structures.</p><p>Electronic processes following ionization constitute the second theme. The post-collision interaction phenomenon, energy exchange between the photo- and the Auger electrons, is shown to be different in clusters of argon, krypton and xenon. A model is proposed that takes polarization screening in the final state into account. This result is of general character and should be applicable to the analysis of core level photoelectron and Auger electron spectra of insulating and semi-conducting bulk materials as well.</p><p>Interatomic Coloumbic Decay is a process that can occur in the condensed phases of weakly bonded systems. Results on the time-scale of the process in Ne clusters and mixed Ar/Ne clusters are herein discussed, as well observations of resonant contributions to the process. In analogy to Auger <i>vis-à-vis</i> Resonant Auger it is found that to the ICD process there is a corresponding Resonant ICD process possible. This has later been observed in other systems and by theoretical calculations as well in subsequent works by other groups.</p><p>Delocalization of dicationic valence final states in the hydrogen bonded ammonia clusters and aqueous ammonia has also been investigated by Auger electron spectroscopy. With those results it was possible to assign a previously observed feature in the Auger electron spectrum of solid ammonia.</p> Cluster nanoparticle Heterogeneous Homogeneous Mixed Cluster production methods co-expansion pick-up doping Cluster geometry radial segregation Interatomic Coulombic Decay ICD Auger electron spectroscopy AES X-ray photoelectron spectroscopy XPS Ultra-violet spectroscopy UPS Noble gas Rare gas Ne Ar Kr Xe Ammonia NH3 Sulphur hexafluoride SF6 MAX-lab BESSY Physics Fysik
145	Photoelectron Spectroscopy on Atoms, Molecules and Clusters : The Geometric and Electronic Structure Studied by Synchrotron Radiation and Lasers Rander, Torbjörn January 2007 (has links) Atoms, molecules and clusters all constitute building blocks of macroscopic matter. Therefore, understanding the electronic and geometrical properties of such systems is the key to understanding the properties of solid state objects. In this thesis, some atomic, molecular and cluster systems (clusters of O2, CH3Br, Ar/O2, Ar/Xe and Ar/Kr; dimers of Na; Na and K atoms) have been investigated using synchrotron radiation, and in the two last instances, laser light. We have performed x-ray photoelectron spectroscopy (XPS) on all of these systems. We have also applied ultraviolet photoelectron spectroscopy (UPS), resonant Auger spectroscopy (RAS) and near-edge x-ray absorption spectroscopy (NEXAFS) to study many of the systems. Calculations using ab initio methods, namely density functional theory (DFT) and Møller-Plesset perturbation theory (MP), were employed for electronic structure calculations. The geometrical structure was studied using a combination of ab initio and molecular dynamics (MD) methods. Results on the dissociation behavior of CH3Br and O2 molecules in clusters are presented. The dissociation of the Na2 molecule has been characterized and the molecular field splitting of the Na 2p level in the dimer has been measured. The molecular field splitting of the CH3Br 3d level has been measured and the structure of CH3Br clusters has been determined to be similar to the structure of the bulk solid. The diffusion behavior of O2, Kr and Xe on large Ar clusters, as a function of doping rate, has been investigated. The shake-down process has been observed from excited states of Na and K. Laser excited Na atoms have been shown to be magnetically aligned. The shake-down process was used to characterize the origin of various final states that can be observed in the spectrum of ground-state K. Atomic and molecular physics Free clusters Electron spectroscopy Doped clusters Laser excitation Alkali metals Electronic structure Geometric structure X-ray photoelectron spectroscopy (XPS) Resonant Auger spectroscopy (RAS) Detuning Ultra-fast dissociation (UFD) Sodium Potassium Oxygen Bromomethane Argon Xenon Krypton Molecular field splitting Core hole lifetime Core excitation Atom- och molekylfysik
146	A Treatise on the Geometric and Electronic Structure of Clusters : Investigated by Synchrotron Radiation Based Electron Spectroscopies Lindblad, Andreas January 2008 (has links) Clusters are finite ensembles of atoms or molecules with sizes in the nanometer regime (i.e. nanoparticles). This thesis present results on the geometric and electronic structure of homogeneous and heterogeneous combinations of atoms and molecules. The systems have been studied with synchrotron radiation and valence, core and Auger electron spectroscopic techniques. The first theme of the thesis is that of mixed clusters. It is shown that by varying the cluster production technique both structures that are close to that predicted by equilibrium considerations can be attained as well as far from equilibrium structures. Electronic processes following ionization constitute the second theme. The post-collision interaction phenomenon, energy exchange between the photo- and the Auger electrons, is shown to be different in clusters of argon, krypton and xenon. A model is proposed that takes polarization screening in the final state into account. This result is of general character and should be applicable to the analysis of core level photoelectron and Auger electron spectra of insulating and semi-conducting bulk materials as well. Interatomic Coloumbic Decay is a process that can occur in the condensed phases of weakly bonded systems. Results on the time-scale of the process in Ne clusters and mixed Ar/Ne clusters are herein discussed, as well observations of resonant contributions to the process. In analogy to Auger vis-à-vis Resonant Auger it is found that to the ICD process there is a corresponding Resonant ICD process possible. This has later been observed in other systems and by theoretical calculations as well in subsequent works by other groups. Delocalization of dicationic valence final states in the hydrogen bonded ammonia clusters and aqueous ammonia has also been investigated by Auger electron spectroscopy. With those results it was possible to assign a previously observed feature in the Auger electron spectrum of solid ammonia. Cluster nanoparticle Heterogeneous Homogeneous Mixed Cluster production methods co-expansion pick-up doping Cluster geometry radial segregation Interatomic Coulombic Decay ICD Auger electron spectroscopy AES X-ray photoelectron spectroscopy XPS Ultra-violet spectroscopy UPS Noble gas Rare gas Ne Ar Kr Xe Ammonia NH3 Sulphur hexafluoride SF6 MAX-lab BESSY Physics Fysik
147	Structure and Dynamics of Core-Excited Species Travnikova, Oksana January 2008 (has links) In this thesis we have performed core-electron spectroscopy studies of gas phase molecular systems starting with smaller diatomic, continuing with triatomic and extending our research to more complex polyatomic ones. We can subdivide the results presented here into two categories: the first one focusing on electronic fine structure and effect of the chemical bonds on molecular core-levels and the other one dealing with nuclear dynamics induced by creation of a core hole. In our research we have mostly used synchrotron radiation based techniques such as X-ray Photoelectron (XPS), X-ray Absorption (XAS), normal and Resonant Auger (AES and RAS, respectively) and Energy-Selected Auger Electron PhotoIon COincidence (ES-AEPICO) spectroscopies. We have demonstrated that resonant Auger spectroscopy can be used to aid interpretation of the features observed in XAS for Rydberg structures in the case of Cl2 and C1s−1π*1 states of allene molecules. The combined use of high-resolution spectroscopy with ab initio calculations can help the interpretation of strongly overlapped spectral features and disentangle their complex profiles. This approach enabled us to determine the differences in the lifetimes for core-hole 2p sublevels of Cl2 which are caused by the presence of the chemical bond. We have shown that contribution in terms of the Mulliken population of valence molecular orbitals is a determining factor for resonant enhancement of different final states and fragmentation patterns reached after resonant Auger decays in N2O. We have also performed a systematic study of the dependence of the C1s resonant Auger kinetic energies on the presence of different substituents in CH3X compounds. For the first time we have studied possible isomerization reaction induced by core excitation of acetylacetone. We could observe a new spectral feature in the resonant Auger decay spectra which we interpreted as a signature of core-excitation-induced keto-enol tautomerism. Physics Synchrotron radiation X-ray Photoelectron Spectroscopy (XPS) X-ray Absorption Spectroscopy (XAS) Resonant Auger Spectroscopy (RAS) Auger Electron Spectroscopy (AES) core excitation core ionization linear free energy relationships (LFER) molecular-field splitting substituent effects nuclear dynamics isomerization Cl2 N2O methane derivatives allene acetylacetone Fysik
148	Theoretical Investigations Of Core-Level Spectroscopies In Strongly Correlated Systems Gupta, Subhra Sen 12 1900 (has links) Ever since the discovery of exotic phenomena like high temperature (Tc) superconductivity in the cuprates and colossal magnetoresistance in the manganites, strongly correlated electron systems have become the center of attention in the ﬁeld of condensed matter physics research. This renewed interest has been further kindled by the rapid development of sophisticated experimental techniques and tremendous computational power. Computation plays a pivotal role in the theoretical investigation of these systems, because one cannot explain their complicated phase diagrams by simple, exactly solvable models. Among the plethora of experimental techniques, various kinds of high energy electron spectroscopies are fast gaining importance due to the multitude of physical properties and phenomena which they can access. However the physical processes involved and the interpretation of the spectra obtained from these spectroscopies are extremely complex and require extensive theoretical modelling. This thesis is concerned with the theoretical modelling of a certain class of high energy electron spectroscopies, viz. the core-level electron spectroscopies, for strongly correlated systems of various kinds. The spectroscopies covered are Auger electron spectroscopy (AES), core-level photoemission spectroscopy (core-level PES) and X-ray absorption spec- troscopy (XAS), which provide non-magnetic information, and also X-ray magnetic circular and linear dichroism (XMCD and XMLD), which provide magnetic information. . Spectroscopy High Temperature Superconductors Electronic Structure High Energy Electron Spectroscopies Auger Electron Spectroscopy (AES) X-ray Absorption Spectroscopy (XAS) X-ray Magnetic Circular Dichroism (XMCD) X-ray Magnetic Linear Dichroism (XMLD) Strong Correlations Manganites Unusal Doping Magneto-crystalline Anisotropy Optics
149	Elektronenspektroskopie und Faktoranalyse zur Untersuchung von ionenbeschossenen Metall (Re, Ir, Cr, Fe)-Silizium-Schichten Reiche, Rainer 29 January 2000 (has links) (PDF) No description available. Augerelektronenspektroskopie (AES) Augerparameter Chrom Defektgenerierung Eisen Eisenimplantation Ionenbeschuß Konzentrationsprofile Auger electron spectroscopy (AES) Photoelectron spectroscopy (XPS) QUASES Re-Si band structure defect generation d ddc:29 rvk:UP 9300 Elektronenspektroskopie Faktorenanalyse Ionenbestrahlung Mehrschichtsystem Metall Silicium
150	Solvent–Solute Interaction : Studied by Synchrotron Radiation Based Photo and Auger Electron Spectroscopies Pokapanich, Wandared January 2011 (has links) Aqueous solutions were studied using photoelectron and Auger spectroscopy, based on synchrotron radiation and a liquid micro-jet setup. By varying the photon energy in photoelectron spectra, we depth profiled an aqueous tetrabutylammonium iodide (TBAI) solution. Assuming uniform angular emission from the core levels, we found that the TBA+ ions were oriented at the surface with the hydrophobic butyl arms sticking into the liquid. We investigated the association between ions and their neighbors in aqueous solutions by studying the electronic decay after core ionization. The (2p)−1 decay of solvated K+ and Ca2+ ions was studied. The main features in the investigated decay spectra corresponded to two-hole final states localized on the ions. The spectra also showed additional features, related to delocalized two-hole final states with vacancies on a cation and a neighboring water molecule. These two processes compete, and by comparing relative intensities and using the known rate for the localized decay, we determined the time-scale for the delocalized process for the two ions. We compared to delocalized electronic decay processes in Na+, Mg2+, and Al3+, and found that they were slower in K+ and Ca2+, due to different internal decay mechanisms of the ions, as well as external differences in the ion-solute distances and interactions. In the O 1s Auger spectra of aqueous metal halide solutions, we observed features related to delocalized two-hole final states with vacancies on a water molecule and a neighboring solvated anion. The relative intensity of these feature indicated that the strength of the interaction between the halide ions and water correlated with ionic size. The delocalized decay was also used to investigate contact ion pair formation in high concentrated potassium halide solutions, but no concrete evidence of contact ion pairs was observed. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 726 Interatomic Coulombic Decay ICD Auger electron spectroscopy AES X-ray photoelectron spectroscopy XPS Ultra-violet spectroscopy UPS localized delocalized double ionization potential DIP two hole final states Water H2O Potassium chloride KCl Calcium chloride CaCl2 Ammonium NH4 Core hole clock lifetime solvated ion alkali halide Coster Kronig MAX-lab BESSY Liquid physics Vätskefysik

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