Page 47 - Tandem Techniques
P. 47
Page 29
pointed out that resolution depends not only on the degree of separation but also on the extent to which
the peaks are dispersed (the more narrow the peaks, the higher the efficiency of the column).The
capillary column can be made much longer than the packed column and provide much higher
efficiencies (more narrow peaks) thus the highest resolution achievable for a given inlet pressure will be
obtained from the capillary column. The standard deviation of the eluted peak is given by the following
equation [23],
where (s) is the standard deviation of the peak,
and (n) is the column efficiency in theoretical plates.
Substituting for (VR ) from equation (1.1),
Now
and as (Vo) the dead volume of the column is about 60% of the total column volume,
where (r) is the radius of the column,
and (1) is the length of the column
Substituting for (Vo) in equation (6), and for (V +KV ) in equation (1.5),
L
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