Sulphur dioxide, fluorescence

Di-(l-naphthylmethyl)sulphone forms an excimer but does not react to give an intramolecular cycloaddition product like the corresponding ether but rather fragments to give sulphur dioxide and (l-naphthyl)methyl radicals (Amiri and Mellor, 1978). I-Naphthylacetyl chloride has a very low quantum yield of fluorescence and this is possibly due to exciplex formation between the acyl group and the naphthalene nucleus (Tamaki, 1979). Irradiation leads to decarbonylation. It is known that acyl chlorides quench the fluorescence of aromatic hydrocarbons and that this process leads to acylation of the aromatic hydrocarbon (Tamaki, 1978a). The decarboxylation of anhydrides of phenylacetic acids [171] has been interpreted as shown in (53), involving... [Pg.112]

Several direct spectrophotometric methods are used for the sulphur dioxide measurement, including non-dispersive infrared absorption, ultraviolet absorption, molecular resonance fluorescence and second-derivative spectrophotometry. [Pg.589]

EN-14212 (2012) Ambient air—standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence. European Regulations... [Pg.103]

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