185 nm radiation measurement of high output low pressure mercury lamps

Abstract

Abstract-For many years the low pressure mercury lamps are widely used in general lighting and ultraviolet radiation. Because of its strong 254 nm ultraviolet and 185 nm vacuum ultraviolet radiation, it has played a very active role in environment, agriculture and medical fields. In environmental treatments, 254 nm radiation has been used for disinfecting the air and water, while the 185 nm radiation is applied to the degradation of organic matter. In this paper, the 185 nm radiation of high output low pressure mercury lamp, with 80 cm in length, was measured in a customized vacuum chamber based on Keitz method. The radiant characteristics of the lamp was discussed, indicating that the 185 nm radiant efficiency reached the maximum of 11% at the cold spot temperature 70 °C while it is negatively related to the discharge current.

A novel approach to interpret quasi-collimated beam results to support design and scale-up of vacuum UV based AOPs

“…2 ), rendering D total for a given sample in VUV+UV, VUV+UV/H 2 O 2 and UV/H 2 O 2 AOPs as approximately the same. D UV is the major contributor because of the substantially higher UV output of LP-Hg lamps ( = 25–40% and = 6–11%; ( An et al., 2015 ; Schalk et al., 2005 )) and the extremely low penetration depth of VUV compared to UV. For example, in the RO sample, VUV+UV AOP (in the absence of H 2 O 2 ), D UV does not contribute to degradation of CBZ (see Table 5 ) due to negligible direct photolysis at UV.…”