Abstract: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.

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: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.

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: Methods and devices for removing gas prior to detecting analyte ions are discolored. In one aspect of the invention, gas by-products from the suppression of the mobile phase are removed prior to detecting analyte ions at a detector. In another aspect, the amount of dissolved carbonic acid is reduced in a suppressed carbonate/bicarbonate mobile phase by removing carbon dioxide gas.

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: A system and method for electrochemically regenerated ion neutralization and concentration is disclosed. In one aspect of the invention, a system is provided comprising a HPLC column pump, a concentrator column, an analytical column, a suppressor, a detector, a mixed bed deionizing resin, a sample injector, and a neutralization cartridge.

Abstract: A plastic skating surface comprising at least two sheets of plastic welded together. The plurality of welded sheets of plastic form a continuous skating surface, wherein the effects of expansion and contraction due to temperature change is limited to the outer perimeter of the skating surface. An expansion plate overlaps the outer perimeter of the skating surface, thereby defining a fixed enclosure of the skating surface.

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: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.

Abstract: A system and method for electrochemically regenerated ion neutralization and concentration is disclosed. In one aspect of the invention, a system is provided comprising a HPLC column pump, a concentrator column, an analytical column, a suppressor, a detector, a mixed bed deionizing resin, a sample injector, and a neutralization cartridge.

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: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.