Frequency electrodeless

Mechanisms such as the brush light arc, the charged water bubble, afterglow phenomena, and diffusion combustion of small gas admixts in air have been suggested, and explain one or more features of the phenomenon but fail to explain others. High-frequency electrodeless discharges have some of its features. 

In high frequency electrodeless discharges the complications of the cathode and anode regions are absent, the entire plasma is approximately... 

Baselyan, E.M., Raizer, Yu.E (1997), Spark Discharge, Moscow Institute of Physics and Technology, Moscow. Bashkirov, Y.A., Medvedev, S.A. (1968), Application of a Radio-Frequency Electrodeless Discharge for Synthesis of Niobium-Vanadium Intermetallic Compounds, in Low Temperature Plasma Generators, p. 501, Energia (Energy), Moscow. 

Gl. Gleit, C. E., High frequency electrodeless discharge system for ashing organic matter. And. Chem. 37, 314- 15 (1965). 

Electrodeless discharge lamps (EDLs) emit radiation as a result of radio frequencies providing the exciting energy. 

It has been shown that a high frequency of modulation of the electrodeless discharge lamp (e g. 10 kHz) is advantageous. This frequency is well away from the low frequency of flame noise. If the amplifier is locked-in to this high frequency via a reference signal, an optimum signal-to-noise ratio is achieved. 

RF discharges are classified in accordance to their electrode or electrodeless nature into capacitively or inductively coupled. In the case of the inductively coupled discharge, a helical or flat copper coil is utilised. Inductive coupling is generally used at AC frequencies greater than 1 MHz as it becomes less efficient at lower frequencies. Although systems are often described as inductively coupled this may not be the case as the skin depth (the distance over which the electromagnetic radiation is absorbed) is often in excess of the reactor dimensions. This is certainly the case for the 13.56 MHz systems widely employed for polymer deposition. 

Electrodeless discharge lamps, or EDLs (Fig. 3), are easy to make, but the results obtained are not always reproducible owing to chemical effects with the walls of the lamp, poor outgassing, poor seal-off, etc. A tesla coil starter produces a few free electrons that are accelerated by a high-frequency electric field (through the... 

Electrodeless discharge lamp A source of atomic line spectra that is powered by radio-frequency or microwave radiation. Electrode of the first kind A metallic electrode whose potential is proportional to the logarithm of the concentration (strictly, activity) of a cation (or the ratio of cations) derived from the electrode metal. 

In the hollow cathode lamps of these relatively volatile elements self-absorption at low discharge currents may also be considerable and even self-reversal may take place. This is not the case with electrodeless discharge lamps. They consist of a quartz balloon in which the halogenide of the element is present. The analyte spectra are excited with the aid of a high-frequency (MHz range) or a microwave field (GHz range), supplied e.g. through an external antenna. 

High yields of gaseous hydrocarbons from H2 + CO have now been shown to occur in low-frequency [50 Hz. (8) and 60 Hz. (24)] discharges between electrodes, and electrodeless radiofrequency (2-110 MHz.) (6) and microwave (2450 MHz.) discharges. However, in all of these cases, the reaction does not appear to be an extremely rapid one, such as is the case for dissociation of diatomic molecules in a discharge, for instance. 

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