840 



METHODS OF KINETIC MEASUREMENTS 



CHAP. 25 



sumed per quantum absorbed) can be obtained over a considerable range 

 of wave lengths and intensities. The convenience of this actinometer is 

 the possibility of using it in conjunction with Warburg reaction vessels in 

 a manometric sj^stem. Assuming equal absorption of light in the reaction 



300 



400 500 



WAVE LENGTH, m/i 



600 



700 



Fig. 25. 2A. Spectral sensitivity curve of a selenium barrier layer cell (Wes- 

 ton Photronic Cell). 



20 



.^ 16 



C 

 D 



> 12 

 > 



i B 



lu 



V) 



4 - 



G.E. Pj 

 22(Cs) 



G E. ly 

 405 (No) 



RC.A. 910 (photomultiplier) 



200 300 400 500 600 

 WAVE LENGTH, m/i 



700 



800 



Fig. 25.2B. S'lHictral .sen.sitivit.y curves of three typical vacuum-type photocells. 



vessel and in the actinometer vessel, and arranging for identical light fluxes 

 to reach both vessels (e. g., by placing them side-by-side in a uniform light 

 field, or by alternating the reaction vessel and the actinometer vessel in 



