000001454 001__ 1454
000001454 035__ $$a34565 
000001454 037__ $$aROMDOC-THESIS-2017-937
000001454 041__ $$arum
000001454 100__ $$aHărăbor, Novac Adrian
000001454 245__ $$aCaracterizarea spectrală şi determinarea temperaturii electronilor pentru lămpile HID cu mercur şi halogenuri metalice expuse iradierii cu raze X modelarea cu metoda Chapman-Enskog a plasmei de descărcare
000001454 260__ $$c2012-04-29
000001454 520__ $$aFACULTY OF APPLIED SCIENCE – DEPARTMENT OF PHYSICS „Spectral characterization and electron temperature measuring for mercury HID and Metal Halide lamps exposed to X-rays. Discharge plasma modeling using the Chapman-Enskog method.” Author: Novac Adrian HĂRĂBOR Director: Prof.dr.ing. Ion M. POPESCU (UPB) Co-director: Prof.dr. Georges Zissis (Université de Toulouse) Abstract: Phenomenological and theoretical aspects specific to discharge lamps (quality of emitted light and visual perception of human eye, the arc-electrode interaction, specific methods to measure plasma temperature and electrode temperature) are presented in the first four chapters. In chapter 4 are also included original contributions on electron temperature measurement (Te) by Thomson scattering method (with laser INNOVA 308 C) for MH-400W lamp and the obtained X-ray absorption profiles of plasma density and of the electron temperature, Te, in the case of HID lamps with Hg. Optical emission spectrometric measurements (chapter 5) carried out simultaneously with X-ray irradiation for some HID lamps with Hg (operating at different powers) and for a MH lamp (with Hg, TlI, DyI3, EuI3) highlights that by X-ray exposure we have the increasing of intensities of spectral lines for all plasma components, atoms or ions (including Ba+, Ca+, Y+ ions coming from emissive material deposited on the electrode). But the electron temperature, Te (depending on operating power) does not undergo significant changes. Since monochromatic X radiation of Cu-Kα type enters the plasma discharge in a very small percentage because it is strongly absorbed by the wall of the lamp (made of SiO2), we concluded that the essential role in the changes of spectral line intensities is due to the Auger electrons coming from SiO2, that are entering in the discharge plasma, contributing to the processes of plasma collisions with heavy species followed by their excitement, de-excitation leading to emission of electromagnetic radiation. This hypothesis is confirmed by the representation of the spectral line width versus (Te)1/2 through the Lorentz broadening in the two cases: irradiated and non-irradiated. For the pure Hg discharge lamp the role played by the “phosphor” (YVO4-Eu3+) in UVvisible conversion was explained through experimental evidence. Chapter 6 presents the plasma modeling by Chapman-Enskog method, where it is assumed that the electron temperature, Te, is greater than the heavy particle temperature, Th. Original contributions on the Chapman- Enskog method to calculate the discharge plasma parameters for complex plasmas are also included .
000001454 6531_ $$aSurse electrice de lumină -- Teză de doctorat
000001454 6531_ $$aFizica plasmei -- Teză de doctorat
000001454 6531_ $$aAnaliză spectrală -- Tuburi cu descărcări -- Teză de doctorat
000001454 8560_ $$ff_costache@library.pub.ro
000001454 8564_ $$uhttp://romdoc.upb.ro/record/1454/files/$$zAccess to Fulltext
000001454 980__ $$aTHESIS