In the study of gas chromatography a model is presented to simulate
a capillary gas chromatographic system. The model was developed
to study the concentrations of sample gas as a function of time and
space as it travels through the capillary column. The molecular migration
was approximated by elementary diffusion...
Gas-solid chromatography often has asymmetrical elution
peaks. This is attributed to nonlinear isotherms, multi-energy
adsorption sites, and slow processes. This study utilized a stopflow
gas chromatograph with various NaOH and NaCl modified
aluminas as adsorbents and methane as adsorbate to determine the
influence of surface area and pore volume distribution...
The study of the obstructive factor by Hawkes (11) showed a relation
between the obstructive factor and velocity using a continuous
method. Later, Bowers and Hawkes (12) developed a similar method with
some improvements in the apparatus and found out that the obstructive
factor was not flow dependent. This study...
Ultraviolet spectroscopy and dispersive solubility parameters
correlated to the ratios of retention times have proven valuable in
classification of gas chromatography stationary phases by the donor-acceptor
properties. Iodine was directly dissolved into stationary
phases and the absorption frequency shift of complexes was correlated
with the carbon tetrachloride/chloroform retention ratio on...
A unique mass-flow control system for the carrier gas
in gas chromatography is described and evaluated. Carrier
gas flow is controlled by a flow sensor, feedback electronics,
a flow-control valve and a microcomputer. The
flow-rate is monitored by a mass-flow meter by this system
and the flow is adjusted in...