Abstract: An integrated mobile phase degassing and blending apparatus for transport of liquid chromatography fluids therethrough includes a component having a first portion and a second portion, with the first portion defining an enclosed degassing chamber, and the second portion including a mobile phase blending device, wherein the degassing chamber and the mobile phase blending device are operably coupled to one another such that the liquid chromatography fluids pass directly into the blending device from the degassing chamber. In a particular embodiment, the degassing chamber is specifically configured to accommodate multiple distinct flexible degassing tubes.

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 microscope slide receptacle system for positionably receiving and releasably holding specimen retaining microscope slides in a generally vertical disposition. The system includes a plurality of hinged first and second frames each frame comprising a generally inverted "U"-shaped changer and having complementary coupling hinges for inter-coupling multiple frames together to form the system. A releasable clip is fastened to the frame structure for engaging and supporting the slides. Each frame has a support hanger along the upper surface to permit coupling to a system support.

Abstract: An improved receptacle or holder for microscope slides used in scientific, medical or medically related procedures, with the receptacles being configured to positionably receive, hold and index microscope slides either vertically or horizontally by means of an articulated array of individual holders. The design further minimizes slide-to-cradle contact, with the configuration allowing for rapid drainage of liquids from the slide surfaces. The cradle is also configured to facilitate manual grasping of the edge surfaces of slides being held within the cradle.

Abstract: A microprocessor controlled, general purpose gene synthesizer for programmably synthesizing selected nucleotide sequences. Depending upon a programmed chemistry, metered volumes of selected bases and reagent/solvents are sequentially metered into the bottom of a reaction cell containing solid-supported nucleotides, where desired linkages are achieved in an agitated suspension. Self-refilling syringe metering and electrically initiated, pneumatically operated valving insures economical, non-contaminated synthesis. Preprogrammed, selectable chemistries and operator programmed sequences are operatively coupled under microprocessor control to ensure a general purpose synthesizer.