Retention flow rate, effect

The possible flow rate effects on retention volume (Section 16.3.4). 

It is seen that the viscosity of the gas will change significantly during a temperature program and, thus, at a constant gas mass flow rate, the inlet pressure will rise proportionally. This increase in inlet pressure will result in an increase in the inlet/outlet pressure ratio and, as a consequence, will extend the retention time and oppose the effect of any increase in temperature. It also follows that the effect of... 

It is seen that a very significant temperature increase occurs particularly at high pressures. It would appear that, due to the poor radial thermal transfer in the column, the thermostat had little effect on the temperature change. Katz et al. [15] concluded that increases in column temperature resulting from high inlet pressures could seriously affect the accuracy of retention measurements. The heat evolved on changing the flow rate from 4 to 18 ml/min., accompanied by a corresponding... 

The retention efficiency of membranes is dependent on particle size and concentration, pore size and length, porosity, and flow rate. Large particles that are smaller than the pore size have sufficient inertial mass to be captured by inertial impaction. In liquids the same mechanisms are at work. Increased velocity, however, diminishes the effects of inertial impaction and diffusion. With interception being the primary retention mechanism, conditions are more favorable for fractionating particles in liquid suspension. 

FIGURE 8.7 Effect of pH on retention of amino acids. Column and flow rate Same as Fig. 8.1. Mobile phase 10 mA1 potassium phosphate with SO mM HFIP pH as indicated (adjusted prior to the addition of HFIP). 

Fig. 2-14. The effect of organic modifier on retention, selectivity and resolution of methionine on teicoplanin CSP (250 x 4.6 mm). The flow rate was 1.0 mL min at ambient temperature (23 °C).

Vasanits, A. and Molnar-Perl, I., Temperature, eluent flow-rate and column effects on the retention and quantitation properties of phenylthiocarbamyl derivatives of amino acids in reversed-phase high-performance liquid chromatography, J. Chromatogr., A, 832,109, 1999. 

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