The Joule-Thomson Effect in Nitrogen

The measurements were made with the same apparatus and procedure as in the case of argon. The effect of the known impurities in the nitrogen, namely argon and oxygen, can be safely neglected. The data for the isenthalpic curves are given in detail and are plotted. The values of the Joule-Thomson coefficient, $\mu$, over the field (-150 to 300°C and 1 to 200 atmos.) are calculated, plotted and tabulated as functions of pressure and temperature. Both upper and lower branches of the inversion curve are measured and the whole inversion curve plotted. The isenthalpic curves, the Joule-Thomson coefficient, and the inversion curve in nitrogen are exceedingly like the corresponding phenomenon in air and in argon. $C_p$ is spread over the pressure range and agrees well with the values of Deming and Shupe, and of Mackey and Krase.