Extended constant transmittance

Stirring of the sample at a constant temperature is essential in the case of highly intense irradiation. A thermoelement in the cell measures an increase in temperature from 20 0 to more than 35 C by long irradiation. The cell compartment permits the use of a flow cell, which can be used to circulate an externally irradiated solution, for example by a las. This extended setup (see Section 4.6) has been used in the examination of the photostability of laser dyes by combined transmittance and las -power measurements [52]. 

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