A viral fluid containing coronavirus OC43 was smeared onto plastic surfaces and irradiated with light at wavelengths of 222, 254, 275 nm emitted by an excimer lamp, ultraviolet a deep LED, respectively. After irradiation varying durations, the virus on surface collected activity measured to compare inactivation capabilities three wavelengths. We found that 275-nm from LED exhibited inactivating...

The current biodosimetry, a primary fluence validation method for ultraviolet (UV) reactors, is confronting some serious challenges (e.g., the high cost and the lack of accurate monitoring of the lamp output), thus greatly limiting its practical application. In this study, a monitored tunable biodosimetry (MTB) was developed to validate the fluence of UV reactors with a lower cost but a higher ...

Phosphor molecules are excited by ultraviolet light emitted during the steady electrical discharge of the low-pressure gas inside the lamp, and subsequently de-excite via emission of visible light. Some of this light is absorbed and re-emitted by the phosphor. In this problem, assume that there are no losses in this absorption/re-emission. Compare the intensity, brightness and étendue of the li...

Evaluation of the detection capabilities of both laser and ultraviolet light sources was performed. The Spectra-Physics Model 171-19 argon ion laser was used in a comparison with the hand held Mineralight multiband ultraviolet lamp, Model UVSL-58 and the Fotodyne Foto UV 410, Model 3-4100. Both techniques were evaluated as to their detection limits for various biological stains. A serial diluti...

The general appearance of certain Azotobacter cultures when viewed under an ultraviolet lamp has been suggested as a suitable method of distinguishing species (Johnstone, 1955). In addition, pH fluorescence curves of the crude culture filtrates of Azotobacter have shown differences which might also be of taxonomic significance in distinguishing the species involved (Johnstone and Fishbein, 1956...

Several homogeneous photo-based advanced oxidation processes-namely photolysis, photo-oxidation, and photo-Fenton oxidation—were investigated for the elimination of ibuprofen in water. The effects several operating parameters, such as lamp type (low or medium pressure mercury, xenon-arc), concentration hydrogen peroxide (0.5 to 7 times stoichiometric amount required mineralization), Fenton reag...