11 









? 







! 











\ 





Run 8 

 Volume: I78cc 

 Flowrote: 511 cc/min 











\ 



-,Gos 



Pressure in Chamber 













^ 



"Equatio 



1 [31 











-o-o— 



— Tn — 



H 



^■^ 





Equilibrium Pressure-j 













n 



20 40 60 80 100 120 



Time in Minutes 



< 



a, .8 

 qI .7 







pEquilibrium P 



ressure 











- — T^i - 



>P 













/ 



^Gos 



quation [31 



1 

 >ressure in Chon 



nber 







- 





/ 





Run 10 ' 

 Volume: 162 cc ' 

 Flowrote: 524 cc/min 











1 1 





20 40 60 80 100 120 



Time in Minutes 



Figure 5 - Response of Meter to Sudden Change in the Concentration of Dissolved Air 



in the Incoming Sample 



The broken line indicates the simulated step change in the air content of the inflowing sample. The circles 

 indicate the observed gas pressure in the chamber. The solid line represents a response of the form given by 

 Equation [3]. 



volume, temperature, and the solubility coefficient for nitrogen are given in the first six col- 

 umns. The next two columns give the observed response time and the computed mixing effi- 

 ciency. The response time given is that for nitrogen; the corresponding response time for 

 oxygen is one-half that for nitrogen inasmuch as the solubility coefficient for oxygen is twice 

 that of nitrogen. The initial pressure, i.e., the pressure in the gas space immediately after 

 the simulated step in the concentration of the inflowing sample, and the equilibrium pressure 

 are also shown in the table. 



COMPARISON WITH VAN SLYKE DETERMINATIONS 



In the preliminary tests of the method with the apparatus represented in Figure 1, com- 

 parisons were made with the indications given by the Van Slyke apparatus and substantial 

 agreement between the two methods was obtained. During the tests summarized in Tpble 2, 

 comparisons were made for the first two runs and for the last two. The last two columns in 

 Table 2 show the pressure approached by the meter and the equilibrium pressure corresponding 



