Abstract: A hanger for supporting a plurality of pipettes adjacent a horizontal support surface. The hanger comprising contiguous mounting and pipette supporting portions. Each supporting portion comprises a pair of substantially parallel, laterally separated support arms extending forward from a back plate to vertically support a pipette body there between. Each mounting portion comprises a spacer extending rearward from the back plate spacing the back plate from a vertical side of a channel frame to which the hangers are mounted. The hangers are connected to the vertical side of the channel frame by screws extending through openings in the back plates of the hangers and into the vertical side of the channel frame. The channel frame, in turn, is secured to a horizontally extending support member by laterally spaced screw members extending vertically through a bottom side of the channel frame to engage the support member.

Abstract: A volume adjustable pipette for aspirating and dispensing precise volumes of liquid comprising an elongated hollow hand-holdable housing supporting a plunger for turning and for axial movement within the housing the pipette including (i) an upper stop which is axially adjustable within the housing in response to a turning of the plunger to adjust the volume of liquid which may be drawn into a tip secured to a lower end of the housing upon upward axial movement of the plunger to the upper stop and (ii) a manually actuated lock mechanism for locking the plunger against rotation to set the volume adjustment for the pipette and comprising a hand-turnable knob for actuating and releasing the lock mechanism by virtue of two thumb and/or finger engageable wings extending outwardly from diametrically opposite sides of the hand-turnable knob a gripping member for fixedly securing the plunger against turning and being actuated by a turning of the hand-turnable knob to force a cam surface of the knob against a cam surfa

Abstract: A replaceable pipette tip comprising a pipette surface contamination protector comprising an upwardly extending projection connected by the shoulder to the proximal end portion for laterally spacing the pipette device from a tube which contains or which is to receive the sample fluid to prevent contamination of an outer surface of the pipette device by contact with the tube into which the pipette tip is inserted.

Abstract: A manual pipette including a delayed action home position latch for engaging only after the plunger unit of the pipette has moved downward through its home position to thereafter releasably connect a moveable bottom stop member to the plunger unit to move therewith and upon an upward return of the plunger unit by the pipette's return spring to engage a home position stop to releasably lock the plunger unit in its home position without any downward force being exerted by the pipette user on the plunger unit.

Abstract: A manual pipette including a magnet assist for generating a magnetic force opposing a return spring force on a plunger unit to aid a pipette user in locating and maintaining the plunger unit at a "home" position within a pipette body and ready for immersion of a pipette tip in a liquid to be drawn into the tip.

Abstract: A multi-mode attachable hanger for a pipette comprising contiguous mounting and pipette supporting portions. The supporting portion comprises a pair of substantially parallel, laterally separated support arms extending forward from a back plate to vertically support a pipette body there between. The mounting portion comprises a spacer extending rearward from the back plate spacing the back plate from a support surface to which the hanger is to be mounted. A connector extends from the spacer to secure the hanger to the support surface with the rear edge surface bearing against the support surface. The connector is characterized by means for securing the hanger to a ferrous surface, a hollow wall, a wooden surface, and in combination comprises one or more of a magnet, screw of adhesive centered with respect to the spacer.

Abstract: A reusable pipette tip rack for successively receiving and dispensing arrays of pipette tips and including a manually releasable latch mechanism for securing a support plate carrying an array of pipette tips flat on the top of a support tray of the pipette tip rack with the array of tips seated in an array of openings in the top of the support tray. The latch mechanism comprises a latch including a laterally extending locking surface on one of the support plate or the support tray and a manually releasable locking member extending from the other of the support plate or the support tray. Preferably, the latch mechanism comprises a combination of two such latches each including a locking member and locking surface located at opposite edges of the support tray of the pipette tip rack.

Abstract: A pipette tip ejector mechanism for a pipette comprising a releasable connector between a lower end of a pipette tip ejector shaft and an upper end of a pipette tip ejector arm. The connector comprises a female receptor extending from either the shaft or arm and a male connector extending from the other of the shaft or arm to axially fit into the female receptor for support thereby. A cantilever is secured at one end to either the shaft or arm to extend along an outer surface thereof. The cantilever carries one of a locking member or a locking shoulder to engage and lock to the other of the locking member or locking shoulder on the shaft or arm to axially lock the arm relative to the shaft as the male connector is inserted into the female receptor.

Abstract: A refill pack for storing and dispensing pipette tips into an empty tip rack. The refill rack comprises a hand-gripable carrier for an array of pipette tips releasably secured relative to the carrier such that after hand positioning the array of tips on the empty tip rack, the carrier may be released from the tips which are then free to be seated on a lower end of a pipette and removed from the tip rack.

Abstract: A refill pack for storing and dispensing pipette tips into a tip rack, comprising a support plate with an array of holes containing disposable pipette tips arranged in an organized array and a carrier for hand positioning the support plate over the tip rack for release of the array of pipette tips into the tip rack.

Abstract: A refill pack of light weight low mass material containing an array of replacement pipette tips for a reusable tip rack. The refill pack comprises a support plate with an array of holes containing pipette tips arranged in an organized manner and including a skirt-like guide for centering and guiding the support plate onto the tip rack with distal end portions of the pipette tips aligned with and vertically entering corresponding holes in an organizing tray in the tip rack.

Abstract: A manual pipette including user controllable latch and trigger mechanisms for releasably locking the plunger of the pipette in a "home" position ready for immersion of the pipette tip in a fluid to be drawn into the tip and further including a user controllable velocity governor for regulating the rate of plunger return from the "home" position to a first or upper stop position in drawing the fluid into the tip.

Abstract: A method and accompanying apparatus for automatically extending the linear dynamic absorbance range of absorbance detectors including multi-lightpath flow cells. The absorbance of a reference beam in a relatively short reference path is multiplied by a ratio of the absorbance of a sample beam in a relatively long sample path to the reference path absorbance in developing a relative absorbance for the sample path beyond its linear dynamic range.

Abstract: A hand held self-contained automated pipette for portable operation having an electrically operated digital linear actuator. The actuator preferably includes a stepper motor driving a rotor. A threaded screw is coaxially positioned within the rotor and is connected to an actuator shaft having elongate grooves slidable in a guide for preventing shaft rotation so that precise linear motion is imparted to the shaft. A pipetting displacement assembly having one of various sizes is removably attached for actuation by a common actuator including programmed movement of a displacing piston in a displacement cylinder to optimize air interface volume, neutralize variations in vacuum pipette effects, and provide an accommodated stroke and readout for improved accuracy while pipetting and/or titrating different ranges of volumes. Upon calibration the piston undertakes immediate excursion to an end of travel limit and after motor slippage is retracted to a home position.

Abstract: A compact high performance absorbance detector including a flashlamp light source and folded optics system with ruled grating reflecting beam splitter for minimizing flash to flash angular pattern and spectral variations of the flashlamp.

Abstract: A fluid sample flow cell characterized by a circumferentially uniform radial fluid flow into an entry port to and/or from an exit port from a fluid passageway through the body of the cell.

Abstract: A fluid sample flow cell including a high pressure fluid tight circumferential edge seal for a window in the body of the flow cell.

Abstract: A hand held self-contained automated pipette for portable operation having an electrically operated digital linear actuator. The actuator preferably includes a stepper motor driving a rotor. A threaded screw is coaxially positioned within the rotor and is connected to an actuator shaft having elongate grooves slidable in a guide for preventing shaft rotation so that precise linear motion is imparted to the shaft. A pipetting displacement assembly having one of various sizes is removably attached for actuation by a common actuator including programmed movement of a displacing piston in a displacement cylinder to optimize air interface volume, neutralize variations in vacuum pipette effects, and provide an accommodated stroke and readout for improved accuracy while pipetting and/or titrating different ranges of volumes. Upon calibration the piston undertakes immediate excursion to an end of travel limit and after motor slippage is retracted to a home position.

Abstract: A liquid chromatography system mixing chamber having a motor-driven magnet situated beside an interior compartment wherein one or more stirring magnets are disposed for mixing solvents fed to the mixing chamber by appropriate metering pumps. A fitting is provided having an expandable ring seal, the fitting being insertable into the interior compartment for effecting a high-pressure seal for preventing leakage of the solvent mixture, while enabling access to the interior of the mixing chamber for maintenance purposes without the need for a tool.

Abstract: A liquid chromatography column apparatus which utilizes sorbent packing material in a tube having a first end portion and a second end portion. The first end portion of the tube includes a plug having a passage therethrough. The plug fits in the tube adjacent the packing material and is movable within the tube. An end fitting is also employed adjacent the plug. The end fitting has a passage therethrough which communicates with the passage of the plug. A seal is used inside the tube between the tube and the end fitting. The second end portion of the tube is enclosed and also includes a passage from the interior to the exterior of the tube. A manually actuable gear mechanism is incorporated in the end fitting of the first end portion of the tube for facilitating application of axial force to the packing material, thereby compressing the packing material so as to eliminate voids and channels in the packing material. Other features are also disclosed.