Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 11 of 11 for “"Guided-ion beam"”.
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Development of an electrospary ionization source and vacuum interface for guided ion beam tandem mass spectrometry experiments: structural and energetic effects in the molecular recognition of amino acids by 18-crown-6
… proteins were determined in a step by step fashion using guided ion beam tandem mass spectrometry techniques. Firstly, 18C6 binding affinities of several peptidomimetic bases (B) that serve as mimics of the side chains of Lys, Arg, and His and n-terminal amino group have been examined to provide …
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Noncovalent Interactions Between Alkali Metal Cation And Aza/thia-Crown Macrocycles: Mass Spectrometric Techniques And Theoretical Studies
… experimental and theoretical description of cation-aza-crown and thia-crown ether interactions with alkali metal cations. Infrared multiple photon dissociation (IRMPD) action spectroscopy and energy-resolved collision-induced dissociation (CID) techniques were used in conjunction with …
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Dissociative charge transfer of organic molecules induced by collisions with the He+ cation. A joint experimental and theoretical study of relevance for the interstellar medium evolution
Collisions with He+ are an important pathway for the destruction of complex organic molecules in the interstellar medium (ISM). We have carried out dissociative charge transfer reactions of He+ with two oxygen containing organic molecules, ubiquitous in ISM: dimethyl ether (DME, CH3OCH3 ) and …
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Singlet Oxygen Oxidation of Guanine, 9-Methylguanine and Guanine-Cytosine Base Pair: Dynamics and Kinetics Revealed by Parallel Gas- and Solution-Phase Experiments and Computations
… elusive. My thesis research has focused on reaction mechanism, dynamics and kinetics of <sup>1</sup>O<sub>2</sub> oxidation of guanine, 9-methylguanine and guanine-cytosine base pair, from the gas-phase bare ions, through hydrated clusters, to aqueous solution. Various techniques have been …
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On the Chemistry of Molecules Containing Silicon, Phosphorus, and Sulfur in the Interstellar Medium
… its many shades. This thesis presents a collection of studies in Laboratory Astrochemistry aimed at providing new experimental data for astrochemical modeling and probing the fundamental chemistry underlying the phenomena investigated. The core of this thesis is the study of the reactivity in …
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Theoretical And Experimental Studies Of Noncovalent Metal Cation Binding And Base Pairing Interactions Of Cytosine And Modified Cytosines
… AND EXPERIMENTAL STUDIES OF NONCOVALENT METAL CATION BINDING AND BASE PARING INTERACTIONS OF CYTOSINE AND MODIFIED CYTOSINES</p> <p>by</p> <p>BO YANG</p> <p>December 2014</p> <p>Advisor: Professor Mary T. Rodgers</p> <p>Major: Analytical Chemistry</p> <p>Degree: Doctor of Philosophy</p> <p>Binding …
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Accurate ionic bond energy measurements with TCID mass spectrometry and imaging PEPICO spectroscopy
… the first, metal-cyclopentadienyl bond dissociation energies (BDEs) were measured for seven metallocene ions (Cp<sub>2</sub>M<sup>+</sup>, Cp = η<sup>5</sup>-cyclopentadienyl = c-C<sub>5</sub>H<sub>5</sub>, M = Ti, V, Cr, Mn, Fe, Co, Ni) using threshold collision-induced dissociation (TCID) …
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Dynamics and Kinetics of Singlet Oxygen Mediated Oxidation of Methionine in the Gas Phase, Hydrated Clusters and Solution
<p>The reaction between methionine (Met) and electronically excited singlet molecular oxygen (O<sub>2</sub>[a<sup>1</sup>Δ<sub>g</sub>]) has been investigated in a systematic fashion, using a home-built electrospray ionization (ESI) guided-ion-beam tandem mass spectrometer (MS). The study started …
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Studies Toward A Detailed Understanding Of The Intrinsic Properties Of Nucleic Acid Constituents: Gas-Phase Conformations, Energetics, And Glycosidic Bond Stability
<p>The gas-phase conformations of the protonated forms of the nucleic acid constituents: nucleosides and mononucleotides, were characterized by infrared multiple photon dissociation (IRMPD) action spectroscopy and theoretical calculations. The IRMPD spectroscopy experiments were performed using a …
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Experimental And Theoretical Studies Of Binding Interactions In Divalent Transition Metal Cation-N-Donor Ligand Complexes: Structures, Sequential Bond Dissociation Energies, Mechanisms And Energetics Of Collision-Induced Dissociation
… of the electronic structure of the metal cation, the nature and number of ligands, as well as the effects of chelation and steric interactions on the geometry and binding strength of transition metal cation-ligand complexes. The experimental studies make use of energy-resolved …
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Consequences of Oxidative DNA Damage: Base-Pair Dissociation, Singlet Oxygenation and DNA-Protein Crosslinking
… (OG) is a common DNA lesion resulting from oxidatively generated damage and pairs with complementary cytidine (C) in Watson Crick base-pairing within duplex DNA. The WC-OG·C lesion, if not recognized or repaired, not only leads to G⋅C→T⋅A transversion mutations (through …