Matches in SemOpenAlex for { <https://semopenalex.org/work/W63161468> ?p ?o ?g. }
Showing items 1 to 76 of
76
with 100 items per page.
- W63161468 abstract "Microwave induced plasmas (MIPs) are used for a number of high-tech applications like material processing, light generation, gas cleaning and spectrochemical analysis. Especially the feature that MIPs can be operated remotely and that the propagation of the microwaves can be manipulated with slits, chokes and dielectra others numerous technological opportunities. This thesis concentrates on low-pressure MIPs as used for the production of optical fibers by the company Draka Communications in Eindhoven. To improve this fabrication process, more insight in the plasma is needed. The modeling of these low pressure plasmas is difficult, since they are far from local thermodynamical equilibrium (LTE). Therefore, an accurate description of transport, chemistry and electromagnetic power coupling is required. Experimental data are needed to validate the results of the plasma models. This study describes the application of several spectroscopic techniques to low-pressure MIPs in pure argon and in mixtures of argon/hydrogen and argon/oxygen. These techniques can be divided in passive methods such as emission spectroscopy and active methods like Thomson scattering, absorption spectroscopy and laser induced fluorescence. Due to the non-LTE character of the plasma, the processing of experimental data obtained from the passive methods is not straightforward: plasma models are required to extract important plasma properties such as the electron density and electron temperature from the data. Therefore, the results have to be compared with the results of active spectroscopy. After validation, the passive methods can be applied to plasmas for which it is not possible to apply the experimentally difficult active techniques, such as in industrial situations. Active spectroscopy can not be applied to the MIPs used at Draka Communications. These plasmas are not easily accessible with passive spectroscopy either since they are shielded from their environment. Therefore, at the TU/e, a microwave setup has been built which resembles the microwave plasmas used at Draka. A surfatron is used to launch electromagnetic surface waves into a small quartz tube filled with argon or oxygen gas. This surfatron setup is small and flexible and is therefore easy to investigate with both passive and laser aided diagnostics. The surfatron induced argon plasma was studied using a number of passive diagnostic methods like absolute line intensity measurements, continuum measurements and H¯-broadening. These results were compared with the results of one active spectroscopic method, laser Thomson scattering. A good agreement between the results was obtained for atomic plasmas. For molecular plasmas, a number of discrepancies were found. These require further investigations. Another aspect of this work is the application of global plasma models. This type of models relates external control parameters such as the microwave power, plasma length, tube radius and gas pressure to the electron density, electron temperature and gas temperature. Also, these models are used to explain the trends observed in experimental results. For atomic argon plasmas, a good agreement between the experimental and global model results was found. For molecular plasmas, it was found that molecule assisted recombination is the main loss process for the electron density instead of ambipolar diffusion, as is the case for atomic plasmas. This implies that an accurate description of the plasma chemistry and kinetic reactions is required." @default.
- W63161468 created "2016-06-24" @default.
- W63161468 creator A5045755488 @default.
- W63161468 date "2008-01-01" @default.
- W63161468 modified "2023-09-23" @default.
- W63161468 title "Spectroscopic study of microwave induced plasmas : exploration of active and passive methods" @default.
- W63161468 cites W1820938075 @default.
- W63161468 cites W2128879224 @default.
- W63161468 cites W2574037551 @default.
- W63161468 doi "https://doi.org/10.6100/ir637283" @default.
- W63161468 hasPublicationYear "2008" @default.
- W63161468 type Work @default.
- W63161468 sameAs 63161468 @default.
- W63161468 citedByCount "1" @default.
- W63161468 countsByYear W631614682012 @default.
- W63161468 crossrefType "journal-article" @default.
- W63161468 hasAuthorship W63161468A5045755488 @default.
- W63161468 hasConcept C121332964 @default.
- W63161468 hasConcept C125287762 @default.
- W63161468 hasConcept C159985019 @default.
- W63161468 hasConcept C184779094 @default.
- W63161468 hasConcept C185592680 @default.
- W63161468 hasConcept C192039680 @default.
- W63161468 hasConcept C192562407 @default.
- W63161468 hasConcept C32891209 @default.
- W63161468 hasConcept C41008148 @default.
- W63161468 hasConcept C43503373 @default.
- W63161468 hasConcept C44838205 @default.
- W63161468 hasConcept C547737533 @default.
- W63161468 hasConcept C60581705 @default.
- W63161468 hasConcept C62520636 @default.
- W63161468 hasConcept C76155785 @default.
- W63161468 hasConcept C82706917 @default.
- W63161468 hasConceptScore W63161468C121332964 @default.
- W63161468 hasConceptScore W63161468C125287762 @default.
- W63161468 hasConceptScore W63161468C159985019 @default.
- W63161468 hasConceptScore W63161468C184779094 @default.
- W63161468 hasConceptScore W63161468C185592680 @default.
- W63161468 hasConceptScore W63161468C192039680 @default.
- W63161468 hasConceptScore W63161468C192562407 @default.
- W63161468 hasConceptScore W63161468C32891209 @default.
- W63161468 hasConceptScore W63161468C41008148 @default.
- W63161468 hasConceptScore W63161468C43503373 @default.
- W63161468 hasConceptScore W63161468C44838205 @default.
- W63161468 hasConceptScore W63161468C547737533 @default.
- W63161468 hasConceptScore W63161468C60581705 @default.
- W63161468 hasConceptScore W63161468C62520636 @default.
- W63161468 hasConceptScore W63161468C76155785 @default.
- W63161468 hasConceptScore W63161468C82706917 @default.
- W63161468 hasLocation W631614681 @default.
- W63161468 hasOpenAccess W63161468 @default.
- W63161468 hasPrimaryLocation W631614681 @default.
- W63161468 hasRelatedWork W1561778983 @default.
- W63161468 hasRelatedWork W1629790796 @default.
- W63161468 hasRelatedWork W191685859 @default.
- W63161468 hasRelatedWork W2021895384 @default.
- W63161468 hasRelatedWork W2038940473 @default.
- W63161468 hasRelatedWork W2042644088 @default.
- W63161468 hasRelatedWork W2057086941 @default.
- W63161468 hasRelatedWork W2203133807 @default.
- W63161468 hasRelatedWork W2551637526 @default.
- W63161468 hasRelatedWork W2600808253 @default.
- W63161468 hasRelatedWork W2784869114 @default.
- W63161468 hasRelatedWork W2888587427 @default.
- W63161468 hasRelatedWork W3004109906 @default.
- W63161468 hasRelatedWork W3012680859 @default.
- W63161468 hasRelatedWork W3041880447 @default.
- W63161468 hasRelatedWork W3088506027 @default.
- W63161468 hasRelatedWork W3176275881 @default.
- W63161468 hasRelatedWork W3208021012 @default.
- W63161468 hasRelatedWork W3212214528 @default.
- W63161468 hasRelatedWork W8567887 @default.
- W63161468 isParatext "false" @default.
- W63161468 isRetracted "false" @default.
- W63161468 magId "63161468" @default.
- W63161468 workType "article" @default.