Abstract: A flow-dampening degassing apparatus for transport of liquid chromatography fluids therethrough includes a substantially burdoin-shaped flexible tube disposed in a reduced-pressure chamber, the tube being sufficiently flexible to expand in a cross-sectional direction upon incursion of a fluid pulsation to thereby increase an inner volume of the tube and correspondingly reduce fluid pressure therein. In a particular embodiment, the tube is fabricated from a gas-permeable and liquid-impermeable material for degassing transported fluids in the reduced-pressure chamber.

Abstract: A flow cell for transporting fluid in a radiant energy field includes a cell structure having an open channel, and one or more end caps having a protrusion extending therefrom, wherein the protrusion may be inserted into the open channel to create a fluid seal. In a particular embodiment, the end caps include open channels for transporting fluid and radiant energy therethrough, and the open channel in the cell structure includes an efficient radiant energy transmission lining that is spaced from the end cap protrusions, thereby forming a gap volume in the flow cell open channel, which gap volume may be calibrated such that radiant energy losses may be standardized in respective flow cells transporting fluids having various indexes of refraction.

Abstract: A system for conducting high-temperature liquid chromatographic analysis includes a mobile phase transport tube configured to operably convey mobile phase from a source to respective chromatographic instruments in the system, a pre-heater apparatus operably coupled to the mobile phase transport tube for heating the mobile phase to a desired temperature, a chromatographic column operably coupled to the pre-heater apparatus, and including temperature-maintaining means for maintaining the column at a pre-determined temperature and a counter-flow heat exchanger operably exchanging heat from outlet mobile phase to inlet mobile phase through conductive heat transfer means. In a particular embodiment, the mobile phase passing through the chromatographic column is maintained in a substantially adiabatic environment.

Abstract: A system for conducting high-temperature liquid chromatographic analysis includes a mobile phase transport tube configured to operably convey mobile phase from a source to respective chromatographic instruments in the system, a pre-heater apparatus operably coupled to the mobile phase transport tube for heating the mobile phase to a desired temperature, a chromatographic column operably coupled to the pre-heater apparatus, and including temperature-maintaining means for maintaining the column at a pre-determined temperature and a counter-flow heat exchanger operably exchanging heat from outlet mobile phase to inlet mobile phase through conductive heat transfer means. In a particular embodiment, the mobile phase passing through the chromatographic column is maintained in a substantially adiabatic environment.

Abstract: A flow cell for transporting fluid in a radiant energy field includes a cell structure having a tube extending therethrough including a radiant energy blocking portion integral therewith. In a particular embodiment, the cell structure includes one or more end caps having a protrusion extending therefrom, wherein the protrusion may be inserted into the tube to create a fluid seal, the end caps including open channels for transporting fluid and radiant energy therethrough, and the tube in the cell structure includes an efficient radiant energy transmission lining that is spaced from the end cap protrusions, thereby forming a gap volume in the flow cell open channel, which gap volume may be calibrated such that radiant energy losses may be standardized in respective flow cells transporting fluids having various indexes of refraction.

Abstract: A system for conducting high-temperature liquid chromatographic analysis includes a mobile phase transport tube configured to operably convey mobile phase from a source to respective chromatographic instruments in the system, a pre-heater apparatus operably coupled to the mobile phase transport tube for heating the mobile phase to a desired temperature, a chromatographic column operably coupled to the pre-heater apparatus, and including temperature-maintaining means for maintaining the column at a pre-determined temperature and a counter-flow heat exchanger operably exchanging heat from outlet mobile phase to inlet mobile phase through conductive heat transfer means. In a particular embodiment, the mobile phase passing through the chromatographic column is maintained in a substantially adiabatic environment.

Abstract: A flow-through vacuum degassing unit for degassing a mobile phase in liquid chromatography applications includes a relatively flat self-supporting thin membrane disposed in a compact degassing component, whereby the thin membrane is gas-permeable and liquid-impermeable to selectively degas a mobile phase. The self-supporting thin membrane is disposed on a permeable substrate through which a vacuum is drawn by a connected vacuum source. In a particular embodiment, the self-supporting membrane may be directly cast on the permeable substrate through a solvent-free thermal process.

Abstract: A system for conducting high-temperature liquid chromatographic analysis includes a mobile phase transport tube configured to operably convey mobile phase from a source to respective chromatographic instruments in the system, a pre-heater apparatus operably coupled to the mobile phase transport tube for heating the mobile phase to a desired temperature, a chromatographic column operably coupled to the pre-heater apparatus, and including temperature-maintaining means for maintaining the column at a pre-determined temperature and a counter-flow heat exchanger operably exchanging heat from outlet mobile phase to inlet mobile phase through conductive heat transfer means. In a particular embodiment, the mobile phase passing through the chromatographic column is maintained in a substantially adiabatic environment.

Abstract: A flow-dampening degassing apparatus for transport of liquid chromatography fluids therethrough includes a substantially burdoin-shaped flexible tube disposed in a reduced-pressure chamber, the tube being sufficiently flexible to expand in a cross-sectional direction upon incursion of a fluid pulsation to thereby increase an inner volume of the tube and correspondingly reduce fluid pressure therein. In a particular embodiment, the tube is fabricated from a gas-permeable and liquid-impermeable material for degassing transported fluids in the reduced-pressure chamber.

Abstract: A flow-through vacuum degassing unit for degassing a mobile phase in liquid chromatography applications includes a relatively flat self-supporting thin membrane disposed in a compact degassing component, whereby the thin membrane is gas-permeable and liquid-impermeable to selectively degas a mobile phase. The self-supporting thin membrane is disposed on a permeable substrate through which a vacuum is drawn by a connected vacuum source. In a particular embodiment, the self-supporting membrane may be directly cast on the permeable substrate through a solvent-free thermal process.

Abstract: A flow-through vacuum degassing unit for degassing a liquid includes a vacuum chamber adapted to be connected to a source for creating a vacuum in the chamber, an inlet and an outlet connection for admitting and discharging liquid to be degassed, a tube for conducting the liquid through the chamber, wherein the tube is a gas permeable polymeric resin material, and a control circuit for operating the source for creating a vacuum in the chamber responsive to a sensed vacuum level in the chamber.

Abstract: A flow cell for transporting fluid in a radiant energy field includes a cell structure having an open channel, and one or more end caps having a protrusion extending therefrom, wherein the protrusion may be inserted into the open channel to create a fluid seal. In a particular embodiment, the end caps include open channels for transporting fluid and radiant energy therethrough, and the open channel in the cell structure includes an efficient radiant energy transmission lining that is spaced from the end cap protrusions, thereby forming a gap volume in the flow cell open channel, which gap volume may be calibrated such that radiant energy losses may be standardized in respective flow cells transporting fluids having various indexes of refraction.

Abstract: A flow-through vacuum degassing unit for degassing a liquid includes a vacuum chamber adapted to be connected to a source for creating a vacuum in the chamber, an inlet and an outlet connection for admitting and discharging liquid to be degassed, a tube for conducting the liquid through the chamber, wherein the tube is a gas permeable polymeric resin material, and a control circuit for operating the source for creating a vacuum in the chamber responsive to a sensed vacuum level in the chamber.

Abstract: A flow-through vacuum degassing unit for degassing a mobile phase includes a vacuum conduit adapted to be connected to a source for creating a vacuum in the conduit, an inlet port and an outlet port for admitting and discharging the mobile phase to be degassed, a degassing tube for conducting the mobile phase through the conduit, wherein the degassing tube is a gas-permeable, liquid impermeable material. In a particular embodiment, the degassing tube receives multiple mobile phases blended together in a discrete volume of desired composition.

Abstract: A flow-through vacuum degassing unit for degassing a liquid includes a vacuum chamber adapted to be connected to a source for creating a vacuum in the chamber, an inlet and an outlet connection for admitting and discharging liquid to be degassed, a tube for conducting the liquid through the chamber, wherein the tube is a gas permeable polymeric resin material, and a control circuit for operating the source for creating a vacuum in the chamber responsive to a sensed vacuum level in the chamber.

Abstract: In a gas chromatograph a valve assembly for providing gradual, uninterrupted re-direction of gas flow between a flow measurement position and a bypass position. The valve assembly maintains constant gas flow through the chromatograph during transition between an auto-zeroing mode in which a flow sensor is calibrated and a flow measurement mode. The valve assembly includes a valve rotor having eccentric grooves formed for providing the desired re-direction of gas flow.

Abstract: A vacuum degassing and solvent delivery apparatus for those solvents being utilized in high pressure liquid chromatographic operations and/or applications. The degassing and delivery apparatus of the present invention is designed for attachment directly to a solvent reservoir, such as a double-ended bottle having a threaded portion along the bottom end thereof. The arrangement facilitates ease of installation and removal of the vacuum degassing, recycling and delivery apparatus so as to accommodate a variety of installation applications and requirements. The solvent degassing system of the present invention further includes the utilization of an atmospheric impermeable composite tubing structure which is effective for isolating fluids from atmospheric contamination during transport.

Abstract: A vacuum degassing and solvent delivery apparatus for those solvents being utilized in high pressure liquid chromatographic operations and/or applications. The degassing and delivery apparatus of the present invention is designed for attachment directly to a solvent reservoir, such as a bottle having a threaded neck portion. The arrangement facilitates ease of installation and removal of the vacuum degassing, recycling and delivery apparatus so as to accommodate a variety of installation applications and requirements. The solvent degassing system of the present invention further includes the utilization of an atmospheric impermeable composite tubing structure which is effective for isolating fluids from atmospheric contamination during transport.

Abstract: A solvent debubbling/priming device for use in high pressure liquid chromatographic applications includes a valve adapted for releasable and sealed attachment to a bubble collecting/solvent reservoir. The valving portion of the device comprises a valve body with bores formed therein for controlled access and communication between the bubble collecting/solvent reservoir and the exterior of the valve, or atmosphere. The solvent debubbling/priming means includes a length of flexible tubing which has a flattened portion at its distal end and with the tubing being in communication with the bubble collecting/solvent reservoir. The flexible tubing along with its flattened portion provides a flow control and check valve which is chemically inert and free of potentially contaminating lubricants for effective utilization.