Microwave generator, electrodeless

Excitation by microwave frequency (245O MHz). Ozy gen under 1 torr pressure is passed through a quartz tube which is part of the discharge section which is connected to electrodeless microwave generator (Fig.1). 

More recently, Streitwieser and Ward conducted the first comprehensive study which was concerned with the full range of condensable products formed from the electrodeless microwave excitation of toluene vapor (9). In this study, flowing toluene vapor in a helium carrier gas stream was excited by a 3 KMHz. microwave generator. The spectrum of the light emitted was not investigated, however the products were carefully determined. The composition of the mixture of products obtained is shown in Table I. 

UV radiation, certainly not sufficient to disrupt the bonds of common organic molecules. We therefore assume that, essentially, photoinitiation is responsible for a chemical change and MW radiation subsequently affects the course of the reaction. The objective of microwave photochemistry is frequently, but not necessarily, connected to the electrodeless discharge lamp (EDL) which generates UV radiation when placed in the MW field. 

Very recently, a novel microwave-assisted high-temperature UV digestion system for accelerated decomposition of dissolved organic compounds or slurries was developed [95, 96]. The technique is based on a closed, pressurized, microwave decomposition device wherein UV irradiation is generated by immersed electrodeless Cd discharge lamps (228 nm) operated by the microwave field in the oven cavity. The immersion system enables maximum reaction temperatures of up to 250-280 °C, resulting in a tremendous increase in mineralization efficiency. 

Electrodeless devices are used to generate cold plasma, typically within a quartz tube by a high-frequency electromagnetic energy. A surface-wave applicator with longitudinal propagation of microwave energy is especially... 

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