초록 ▼

Disclosed are systems and methods that include providing a vessel having an adsorbent disposed therein, the vessel having an inlet and an outlet for communicating a carrier gas through the vessel; determining a differential pressure between the inlet and the outlet for a known flow rate at the outle

Disclosed are systems and methods that include providing a vessel having an adsorbent disposed therein, the vessel having an inlet and an outlet for communicating a carrier gas through the vessel; determining a differential pressure between the inlet and the outlet for a known flow rate at the outlet; and, determining a geometric measure for the vessel based on a ratio of the known flow rate and the differential pressure. In some embodiments, the methods and systems can include a viscosity in the ratio, determining a flow rate at ambient pressure using a factor based on a ratio of a gas pressure at the output and ambient pressure, and/or, determining a flow rate at ambient temperature using a factor based on a ratio of a temperature at the output and ambient temperature.

대표청구항 ▼

What is claimed is: 1. A chromatographic method, comprising: providing a vessel in a carrier gas flow path to a chromatographic column, the vessel comprising: a gas inlet, a gas outlet, and, an adsorbent disposed in the vessel, measuring a differential pressure along the length of the adsorbent, d

What is claimed is: 1. A chromatographic method, comprising: providing a vessel in a carrier gas flow path to a chromatographic column, the vessel comprising: a gas inlet, a gas outlet, and, an adsorbent disposed in the vessel, measuring a differential pressure along the length of the adsorbent, determining a flow rate at the outlet, and, determining a unit flow per unit pressure based on a ratio of the flow rate and the differential pressure. 2. The method of claim 1, further comprising adjusting the unit flow per unit pressure based on a viscosity of the gas. 3. The method of claim 1, further comprising at least one of: determining a flow rate at ambient pressure using a factor based on a ratio of a gas pressure at the output and ambient pressure, and, determining a flow rate at ambient temperature using a factor based on a ratio of a temperature at the output and ambient temperature. 4. The method of claim 1, further comprising heating the vessel to desorb analytes from the adsorbent. 5. The method of claim 1, wherein the vessel comprises an adsorbent trap. 6. The method claims 1, wherein the vessel comprises a sample tube. 7. The method of claim 6, further comprising: providing a second vessel in the carrier gas flow path to the chromatographic column, the second vessel comprising: a gas inlet, a gas outlet, and, an adsorbent disposed in the second vessel, measuring a differential pressure along the length of the adsorbent disposed in the second vessel, determining a flow rate at the outlet of the second vessel, and, determining a second unit flow per unit pressure based on a ratio of the flow rate at the outlet of the second vessel and the differential pressure along the length of the adsorbent disposed in the second vessel. 8. A chromatographic method, comprising: providing a vessel in a carrier gas flow path to a chromatographic column, the vessel comprising: a gas inlet, a gas outlet, and, an adsorbent disposed in the vessel, measuring a differential pressure along the length of the adsorbent, and relating the differential pressure to a flow rate at the outlet to determine a unit flow per unit pressure based on a ratio of the flow rate and the differential pressure. 9. The method of claim 8, further comprising adjusting the unit flow per unit pressure based on a viscosity of the gas. 10. The method of claim 8, further comprising establishing the flow rate at the outlet by controlling the flow of the gas. 11. The method of claim 8, wherein the vessel comprises an adsorbent trap. 12. The method claims 8, wherein the vessel comprises a sample tube. 13. The method of claim 12, further comprising: providing a second vessel in the carrier gas flow path to the chromatographic column, the second vessel comprising: a gas inlet, a gas outlet, and, an adsorbent disposed in the second vessel, measuring a differential pressure along the length of the adsorbent disposed in the second vessel, and, relating the differential pressure along the length of the adsorbent disposed in the second vessel to a flow rate at the outlet of the second vessel to determine a second unit flow per unit pressure based on a ratio of the flow rate at the outlet of the second vessel and the differential pressure along the length of the adsorbent disposed in the second vessel.