Abstract: The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.

Abstract: A supercritical fluid chromatography system is provided with an injection valve subsystem for introducing a sample into a flow of mobile phase fluid. The injection valve subsystem includes an auxiliary valve and an inject valve. The operations of the auxiliary and inject valves are coordinated in such a manner as to reduce sample carry-over and system pressure perturbations occurring during sample injection.

Abstract: Described is a self-sealing thermal enclosure. In various embodiments, the self-sealing thermal enclosure includes an enclosure having a wall with an opening. The enclosure is configured to surround a temperature-controlled environment. The self-sealing thermal enclosure also includes a porous seal disposed adjacent to the wall at the opening. The porous seal is compressible and is fabricated from an open cell foam material. When the porous seal has absorbed a fluid such as a condensate, the temperature-controlled environment is sealed from an ambient environment such that the flow of air into or out of the enclosure is substantially reduced or eliminated.

Abstract: A method includes passing a mobile phase fluid flow comprising liquefied CO2 through a separation column; then introducing a makeup fluid flow into the mobile phase fluid flow to form a mixed fluid flow; and then splitting the mixed fluid flow.

Abstract: The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.

Abstract: A sample manager of a liquid chromatography system uses a sample tray having a base with side walls separated by a cross wall that divides the base into two compartments. The side walls and cross wall bound each compartment on three sides. A fourth side of each compartment is open. Each compartment is sized to closely receive a sample-vial carrier. Each compartment has a magnet affixed to a bottom surface at an edge of the open fourth side. Each of two drawers slides into the open fourth side of one compartment. Each drawer has a support surface with a magnet affixed at an edge of its bottom side, which aligns with the magnet affixed to the bottom surface of the compartment. The magnet of the drawer and the magnet of the compartment bias the drawer into its compartment when the magnets are brought into proximity of each other.

Abstract: A device comprising a pressure monitor and a control means that receives a signal representing measured pressure at the pressure monitor and controls the controllable elements of a fluid system is utilized to monitor a fluid system for error conditions, to optimize operations and to diagnose the fluid system. By following a testing protocol that selectively enables parts of the system, the control means narrows the list of possible failing components. Comparing the measured pressure against normal pressures allows the device to identify error conditions. Determining the volume of fluid being transported and controlling the duration of the flow optimizes operation of the fluid system.

Abstract: A device comprising a pressure monitor and a control means that receives a signal representing measured pressure at the pressure monitor and controls the controllable elements of a fluid system is utilized to monitor a fluid system for error conditions, to optimize operations and to diagnose the fluid system. By following a testing protocol that selectively enables parts of the system, the control means narrows the list of possible failing components. Comparing the measured pressure against normal pressures allows the device to identify error conditions. Determining the volume of fluid being transported and controlling the duration of the flow optimizes operation of the fluid system.

Abstract: The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.

Abstract: Described are techniques for use with a sealing member forming a static seal or a dynamic seal at a surface thereof. The sealing member has at least the surface thereof formed from one of Vespel SCP 5000 or Vespel SCP 50094.

Abstract: Described are techniques for use with an injection port. The injection port includes a needle support structure configured to accommodate a needle containing a sample aspirated therein. The injection port includes a needle seal having a first surface thereof in contact with a second surface of a tip of the needle. A seal is formed when the first surface contacts the second surface and a sufficient force is applied to the needle.

Abstract: Described is an apparatus for reducing a temperature variation of a liquid chromatography sample. A tray drive using at least one of linear or rotational motion moves a sample tray along a path inside a sample compartment of the liquid chromatography system. A control module coordinates the movement of the sample tray by the tray drive and the movement of a sample needle by a needle drive so that any sample in the sample tray can be injected into the mobile phase of the system during a sample load operation. The tray drive is also used to move the sample tray along the path during a temperature averaging period when no loading occurs. Differences in sample temperatures due to variations in the air temperature at different locations inside the sample compartment are reduced, leading to more accurate and repeatable chromatographic measurement results.

Abstract: Described are techniques for force sensing. A computing device is configured to have a desired force setting. A first vertical position of a needle is determined using the computer device. A control signal is sent from the computing device to a positioning device. In response to the control signal, the needle is positioned at the first vertical position. When in the first vertical position, surfaces of a tip of the needle are in contact with surfaces of an opening of a sealing member and positioning the needle causes application of a force at surfaces of the opening in contact with surfaces of the tip of the needle. In response to application of the force, a spring is compressed a distance that is proportional to the force. The force is measured using a force sensor.

Abstract: Described is a self-sealing thermal enclosure. In various embodiments, the self-sealing thermal enclosure includes an enclosure having a wall with an opening. The enclosure is configured to surround a temperature-controlled environment. The self-sealing thermal enclosure also includes a porous seal disposed adjacent to the wall at the opening. The porous seal is compressible and is fabricated from an open cell foam material. When the porous seal has absorbed a fluid such as a condensate, the temperature-controlled environment is sealed from an ambient environment such that the flow of air into or out of the enclosure is substantially reduced or eliminated.

Abstract: Described is a compound sample needle for a liquid chromatography system. In one embodiment, the compound sample needle includes a rigid needle having a coupling end with a face and a counterbore. The compound sample needle also includes a flexible tubing having an outer surface and a coupling end disposed in the counterbore of the rigid needle. The coupling end of the flexible tubing has a face adjacent to a base of the counterbore. The coupling ends of the rigid needle and flexible tubing are secured to each other by a weld formed along a circumference of the outer surface and the face of the rigid needle. A rigid sleeve protects the welded joint. The compound sample needle is suitable for injection into the high pressure mobile phase of ultra performance liquid chromatography systems.

Abstract: Embodiments of the present invention are directed to methods and apparatus for placing a sample in a chromatographic system. The device and method feature placing samples held in a sample loop to pressurization prior to placing such sample loop in communication with high pressure conduits.

Abstract: Embodiments of the present invention feature a method and device for controlling the flow of fluid. One embodiment of the device for controlling the flow of fluid comprises a rotor, stator and compression means. The rotor has a rotor fluid communication means and at least one rotor load bearing surface. The rotor load bearing surface sealably engages a stationary load bearing surface. The rotor is capable of assuming a first position and a second position by rotation. The stator has a stationary load bearing surface having stator fluid communication means. The stationary load bearing surface sealably engages the rotor load bearing surface and permits rotation of the rotor with respect to the stator. At least one of the rotor bearing surface and said stator load bearing surface has a diamond-like carbon-silica coating.

Abstract: A device comprising a pressure monitor and a control means that receives a signal representing measured pressure at the pressure monitor and controls the controllable elements of a fluid system is utilized to monitor a fluid system for error conditions, to optimize operations and to diagnose the fluid system. By following a testing protocol that selectively enables parts of the system, the control means narrows the list of possible failing components. Comparing the measured pressure against normal pressures allows the device to identify error conditions. Determining the volume of fluid being transported and controlling the duration of the flow optimizes operation of the fluid system.

Abstract: A device comprising a pressure monitor and a control means that receives a signal representing measured pressure at the pressure monitor and controls the controllable elements of a fluid system is utilized to monitor a fluid system for error conditions, to optimize operations and to diagnose the fluid system. By following a testing protocol that selectively enables parts of the system, the control means narrows the list of possible failing components. Comparing the measured pressure against normal pressures allows the device to identify error conditions. Determining the volume of fluid being transported and controlling the duration of the flow optimizes operation of the fluid system.

Abstract: The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.