Patent ID: 7219532
Filing Date: 2007-05-22
Classification: G01N

Abstract:
1. A method for regulating fluid flowing through a chromatographic column, the method comprising: providing a sampling device for supplying a carrier gas containing analytes to be measured; providing a chromatographic column for receiving the gas supplied by the sampling device and through which the gas flows from a column inlet to a column outlet; providing a transfer line through which the gas is communicated from the sampling device to the column and through which the gas flows from a transfer line inlet to a transfer line outlet; selecting a desired flow rate F calculating a pressure P where T t is the transfer line absolute temperature, T c is the column absolute temperature, T a is the standard ambient absolute temperature, P o is the gas pressure at the column outlet, P a is the standard ambient pressure, and a and b represent πd/256Lη for the transfer line and the column, respectively, where d is the diameter thereof, L is the length thereof, and η is the viscosity of the gas flowing therethrough; and supplying the carrier gas to the transfer line inlet at the calculated pressure P