Representative distillation curve results, measured with the
advanced approach and apparatus, are presented in table 1 for
the 50/50 (mol/mol) of (n-decane + n-tetradecane), at atmospheric
pressures of (101.00, 82.73, and 70.06) kPa. For each mixture, the
raw temperature (corrected only for the thermocouple calibration)
and the temperature adjusted with the SY equation (in which K1
was assigned a value of 0.000109 for an average carbon chain of
12 units) are presented for each distillate volume fraction. The dramatic
effect of even a modest change in the pressure during the
measurement can be seen from these data. The temperature differences
obtained from measurements at approximately sea level
(where the atmospheric pressure was 101.00 kPa) and those measured
at 3094 m (where the atmospheric pressure was 70.06 kPa)
can be as much as 20 K. Application of the SY equation, which ideally
would cause the three data sets to overlie, clearly brings the
three sets closer together. This is most easily seen graphically.
The data of table 1 are plotted in figures 1a and 1b, showing the
raw and adjusted temperatures, respectively. One can see that all
of the distillation curves show the typical sigmoid-shape characteristic
of a mixture with a heavy and a lighter component (subjected
to a simple rather than fractional distillation) and very
few or no intermediate constituents. The curves begin with a pronounced
upward slope, which then becomes steeper, and subsequent
to this region the curves flatten out. This type of curve is
also called a growth curve, because it describes the weight gain
of mammals from birth to adulthood. Composition of the fluid in