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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.
21

Resonant-infrared laser ablation of polymers mechanisms and applications /

Johnson, Stephen L. January 2008 (has links)
Thesis (Ph. D. in Physics)--Vanderbilt University, Dec. 2008. / Title from title screen. Includes bibliographical references.
22

Pulsed laser-induced material ablation and its clinical applications

Lee, Ho. January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.
23

Mikrometeorologische Prozesse bei der Ablation eines Alpengletschers /

Weber, Markus. January 2008 (has links)
Zugl.: Diss. Univ. Innsbruck, 2004. / Vorgelegt von Michael Kuhn in der Sitzung vom 10. November 2006. Literatur: S. 227-239.
24

The vaporization, thermodynamics, and phase behavior of uranium monosulfide

Cater, E. David. January 1960 (has links)
Thesis (Ph. D.)--University of Kansas, Chemistry, 1960. / "March 1960." "Chemistry - General (TID-4500, 15th ed.)." eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 175-178.
25

Thermal and mechanical phenomena in laser-material interaction

Zhang, Lijun. January 2008 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Mar. 5, 2009). PDF text: 97 p. : ill. (some col.) ; 3.12 Mb. UMI publication number: AAT 3331445. Includes bibliographical references. Also available in microfilm and microfiche formats.
26

Approximate thermal modeling of radiofrequency cardiac ablation /

Walter, Aaron Joseph, January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2005. / Includes bibliographical references (leaves 61-64).
27

The vaporization, thermodynamics, and phase behavior of uranium monosulfide

Cater, E. David. January 1960 (has links)
Thesis (Ph. D.)--University of Kansas, Chemistry, 1960. / "March 1960." "Chemistry - General (TID-4500, 15th ed.)." eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 175-178.
28

Nanostructured Ag produced by LAMA

Albert, André David, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
29

Experimental and theoretical studies on the dynamics of transient plasma plumes generated by laser ablation in various temporal regimes / Etudes expérimentales et théoriques sur la dynamique des plasmas transitoires générés par l'ablation laser dans différents régimes temporels

Irimiciuc, Stefan-Andrei 20 October 2017 (has links)
Les applications de l’ablation laser connaissent un développement important, dans des domaines comme le micro-usinage, la médecine, le nucléaire ou les sciences analytiques. Malgré d’importantes avancées dans la connaissance des interactions complexes intervenant dans ce processus, on a encore besoin d’une meilleure compréhension fondamentale et de modélisation. Le but de ce travail a été d’étudier expérimentalement et théoriquement la dynamique des plasmas transitoires générés par ablation laser dans différents régimes temporels (ns, ps, fs) et d’essayer de corréler le comportement observé avec les propriétés physiques des matériaux ablatés. Nous avons mis en œuvre des méthodes optiques, spectroscopiques et électriques résolues spatialement et temporellement pour l’étude de cibles métalliques mono-éléments et de cibles plus complexes à base de chalcogénures. Cela nous a permis d’avoir une cartographie spatio-temporelle des principaux paramètres du plasma. L’étude en configuration PLD (Pulsed Laser Deposition) a révélé quelques effets particuliers, comme les oscillations ioniques ou la réflexion du plasma sur le substrat. Une version compacte du modèle hydrodynamique fractal a été développée pour simuler la dynamique du plasma. Le modèle théorique réussit à décrire l’évolution spatiale et temporelle des principaux paramètres du plasma (température électronique, vitesses d’expansion, concentration, longueur de Debye, potentiel du plasma). Nous proposons des relations empiriques reliant ces paramètres aux propriétés physiques (conductivités électrique/thermique, mass atomique, chaleur de vaporisation) de la cible. Ces relations transcendent les trois régimes d’ablation. / Laser ablation methods exhibit a fast development in various application fields, as materials processing, medicine, nuclear fusion or analytical sciences. Despite important advances in the knowledge of the complex laser-matter interactions involved in this process, there is still need for better fundamental understanding and modeling. The aim of this work was to experimentally and theoretically investigate the dynamics of transient plasmas generated by laser ablation in various regimes (ns, ps, fs), and to try to correlate the observed behavior with the physical properties of the ablated materials We implemented space- and time-resolved optical, spectroscopic and electrical methods for the study of single-component metallic targets and of complex chalcogenide targets. This led to a space-time mapping of the main plasma parameters. The study performed in actual Pulsed Laser Deposition (PLD) conditions revealed some peculiar effects like ionic oscillations or plume reflection at the substrate. A compact fractal hydrodynamic model was developed to simulate the laser-produced plasma dynamics. The theoretical model accurately describes the spatial and temporal evolution of the main plasma parameters (electronic temperature, expansion velocities, particle number density, Debye length, plasma potential). We report for the first time empirical relations connecting these plasma parameters with the physical properties (electrical/thermal conductivity, atomic mass, heat of vaporization) of the target. These relationships transcend all three ablation regimes (ns, ps, fs).
30

A bronchoscopic microwave ablation applicator: theoretical and experimental investigation

Pfannenstiel, Austin January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / Punit Prakash / Microwave ablation (MWA) is a minimally invasive thermal therapy predominantly used in the treatment of localized cancer. Previous studies have demonstrated clinical use of MWA for treating lung tumors, however, these procedures have relied upon the use of rigid percutaneous MWA applicators which can limit the range of accessible tumors and may have inherent disadvantages for use in lung tissue. The objective of this work was to develop and characterize a bronchoscopic MWA applicator suitable for use in a system that enables bronchoscopic transparencymal nodule access (BTPNA). A 3D coupled FEM electromagnetic-heat transfer model was implemented to optimize the antenna design and evaluate the expected ablation size and shape. A prototype device was fabricated and experimentally evaluated in ex vivo tissue to verify simulation results and demonstrate proof-of-concept. Simulated and experimental results indicate the proposed device could create ablation zones 19.3 – 31.0 mm in diameter with 30 – 45 W of power applied for 5 – 10 minutes. Future bronchoscopic MWA applicators based on the design proposed in this study could allow physicians an even less invasive treatment option for lung cancer with increased accuracy and efficacy and reduced risk of procedural complications immediately following a positive bronchoscopic lung biopsy.

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