UV light sources

TPAs bearing cross-linkable oxetane functionalities (52) (Scheme 3.20) has been developed [95,96], This material can be easily photo-patterned by exposure to a very short wavelength UV light source to form a patterned and insoluble HTL. Similar photo-cross-linkable HTMs based on side-chain acrylate or styryl functional groups have been synthesized (53,54) [97]. A series of spiro-linked and photo-cross-linkable HTMs have been patented by the Canon group [98]. 

Recently, atmospheric pressure photoionization (APPl) has been introduced. [144] APPl can serve as a complement or alternative to APCl. [142,145] In APPl, a UV light source replaces the corona discharge-powered plasma, while the pneumatic heated sprayer remains almost unaffected (Pig. 11.28). [146-148]... 

A similar combination of ultrasound and photocatalysis has also been reported to destroy 2,4,6-trichlorophenol in aqueous solution [39]. An ultrasonic probe (22 kHz) with a uv light source (15 W) was used to examine the effect of changing such operating conditions as ultrasonic intensity, reaction temperature and uv transmission. The experiments involved using 2,4,6-trichlorophenol (100 ppm) and TiOj (0.1 g L ) and showed that the degradation rates increased with the temperature of the solution. The cumulative effect was more pronounced at lower ultrasonic intensities with little additional benefit derived at increased ultrasonic powers. 

An improvement to this technique will be to use a continuous blue/UV light source and replacing the PMT by a compact spectrometer coupled to a CCD (charge-coupled device) for readout, thus accelerating the data acquisition. In the latter case, the scanning and evaluation takes a few milliseconds. 

When insufficient amounts of hydroxyl radicals are available, incomplete degradation of contaminants may occur. Metals or solids in the influent may reduce process efficiency by costing or scaling the UV light source. 

Clear Tech Industries, Inc. www.cleartech.ca UV equipment, UV light sources, measuring equipment... 

Hamamatsu Corporation www.ushamamatsu.com Equipment, UV light sources... 

Heraeus Noblelight GmbH www.heraeus-noblelight.com UV equipment and UV light sources (standard and excimer), ballasts... 

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