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Description:
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An assessment of some of the advantages and disadvantages of various surface analysis techniques applied to the analysis of both the insulators and conductors used in high voltage . -spark gaps is presented . Some of the analysis techniques introduced include Electron Spectroscopy for Chemical Analysis , Auger Electron Spectroscopy , X -ray Fluorescence , and Secondary Ion Mass Spectroscopy . Surface charging makes most analysis techniques incapable of giving useful information about the changes on or near the surface of insulators . Because of the amount of information available from a single ESCA spectrum , such as shifts in binding energies due to the changes in chemical environment , Auger electron peaks due to the relaxation of the atom after photoionization , and the quantitative information , ESCA is the best analysis technique available for the analysis of insulators . Also the problem of surface charging in ESCA is minimal . The analysis of conductors , however , is less complicated because surface charging is no longer a problem . Therefore the use of AES , SIMS , and ESCA can all give some useful information about conductor surfaces . Since there are several damage mechanisms involved in the deterioration of high voltage spark gaps , such as ultraviolet radiation from the arc , heat from the arc , emission of microparticles from the electrodes , and chemically reactive species in gas filled gaps , it is necessary to try to eliminate as many parameters as possible in order to better understand the damage caused by each mechanism . Therefore a vacuum chamber has been built whereby the damage caused by ultraviolet radiation can be separated from the damage caused by other mechanisms . Insulator samples are radiated with ultraviolet radiation and the samples are then analyzed with appropriate surface analysis techniques to determine what , if any , changes the exposure to the radiation caused . |