Abstract: The present invention is directed to a transparent safety cover for sealing the mouth of a pivotally mounted bucket of a centrifuge rotor. The cover has a first surface configured to make telescoping engagement with the sidewall of the rotor bucket. A shoulder adjacent the first surface abuts the top of the bucket to limit the length of engagement. The first surface has an annular groove containing a resilient O-ring which makes a seal between the cover and the bucket. In the upper portion of the cover, there is a raised dome-like structure with a circular aperture at the top. The aperture has inverted conical walls and is sealed by a movable, resilient, sealing plug. The plug has a tapered body and at the lower portion thereof, are wall gripping means for retaining the plug in a raised, unseated, position. With the plug in the unseated position, the bucket is vented to the atmosphere permitting telescoping movement of the cover with respect to the bucket.

Abstract: A device and method for washing an object in a receptacle. The device includes an end portion introducible into and cooperative with the receptacle to define a substantially enclosed space containing the object to be washed. The fluid is introduced into and aspirated from the substantially enclosed space such that the object is movable in the fluid between the end portion and the receptacle.

Abstract: A rotor seat which automatically adjusts its position with respect to the rotor in response to air flow levitation air entering between the rotor and the rotor seat. The central portion of the rotor seat which has a mating design with the design of the bottom of the rotor is free to move in a vertical direction toward or away from the rotor in response to the flow of air. The rotor seat maintains its optimum position relative to the rotor, allowing the rotor to decelerate in a stable manner.

Abstract: An improved bichromatic or polychromatic spectrophotometer comprising means enabling the user to electronically select which wavelength of a preselected pair of wavelengths shall serve as a "sample" wavelength, with the other then serving as a "reference" wavelength.

Abstract: A membrane for use in the determination of calcium ion concentration in an aqueous solution, the membrane being of the type comprising a calcium ion selective component and a carrier material.

Abstract: An improved apparatus for facilitating the practice of a method for determining the conversion efficiency of the NOx converter of an oxides of nitrogen analyzer. An improved ozone control assembly facilitates the control of the ozone content of the gas mixture that is applied to the input of the analyzer. An improved gas flow regulating arrangement allows the composition of the gas mixture to be changed without affecting the flow rate thereof. Together, these structures improve the stability and ease of use of the conversion efficiency detector.

Abstract: An albumin reagent of the type comprising bromcresol green, a buffering agent having a buffering capacity in the pH range of about 4 to about 4.2, and polyoxyethylene(23) lauryl ether. The albumin reagent is characterized in that it contains from about 0.18 to about 0.22 gm/l bromcresol green and has a polyoxyethylene(23) lauryl ether:bromcresol green weight ratio of from about 10:1 to about 12:1.

Abstract: A solid state ion-sensitive measuring electrode is disclosed in which a filler solution comprising sodium silicate is provided between an outer glass membrane of the electrode and an internal metallic wire which serves as a conductor from the electrode to a meter. The filler solution is inserted into the electrode as a liquid, and is subsequently dehydrated to provide a permanent solid-state matrix which is electrically conducting between the outer glass membrane and the internal wire.

Abstract: A master slave controller communication system is disclosed wherein intercommunication occurs between a master controller and a slave controller over the same communication control line. The communication control line contains three busses. At least one bus is a forward/reverse bus and a second bus is a power bus.

Abstract: A stable enzyme reference composition having an excellent shelf-life. The composition comprises at least one enzyme of known value; about 20 to about 40 weight percent of at least one alkylene polyol having from 2 to 5 carbon atoms; about 3 to about 8 grams (gm) per deciliter (dl) total protein present in a human serum albumin matrix; and about 60 to about 80 weight percent water.

Abstract: A carbon monoxide detection apparatus and process are disclosed in which the amount of carbon monoxide is measured by oxidizing it and measuring the heat of oxidation. To accomplish this platinum oxide is used as the catalyst and an operating temperature is maintained at which oxidation of carbon monoxide occurs in the presence of platinum oxide. Various types of heat-change-responsive techniques are disclosed, including measurement of the voltage drop across forward-biased solid-state diodes, and measurement of the voltage generated by thermo-couples.

Abstract: An improved blood serum reference composition of the type comprising blood serum having constituents of known values, characterized in that said composition further comprises a water soluble amine chloride. The water soluble amine chloride is employed to adjust the negative electrolyte balance of said reference composition without interfering with presently employed blood serum clinical assay procedures or analytical equipment used therein.

Abstract: A method and apparatus for conveying liquids to and from a reaction cell in an automated sample handling apparatus. The conveyance apparatus includes a track and car system. A method and apparatus is disclosed which precisely positions the cars on the track. This positioning method and apparatus includes a plurality of apertures and spaces on the track of a size and spacing to allow the cars to accurately position themselves.

Abstract: In accordance with the present invention, there is provided an air driven centrifuge including a rotor housing having an access door in which there is mounted the illuminating and sensing elements of a photo-optical tachometer with the elements so constructed and arranged that they are positioned over the rotor when the door is in a closed position. There is also provided a rotor cover having at least a portion of its surface conditioned to alternately absorb and reflect incident light, and digital display means to display the rotor speed in R.P.M.

Abstract: A lubricating system which is completely self contained within the vacuum environment of an electric direct drive system for an ultracentrifuge rotor. The lubricating system also functions as a cooling means for an electric motor within the drive system by the use of a unique cooling feed tube in the central portion of the drive system. An orifice in the top of the cooling feed tube will control the head of the lubricating medium within the system. Specific design of the fit between the direct drive assembly and the drive housing in conjunction with the head on the lubricating medium will regulate the drip rate of the lubricating medium to the bearings. The use of the unique lubrication and cooling system maintains the close tolerances of the various elements such as the high speed bearings of the drive system because the temperature of the overall drive system is controlled.

Abstract: An electrophoretic gel of the type comprising a polysaccharide. The electrophoretic gel is characterized in that it further comprises either an acid polysaccharide and salts thereof, wherein the acid moiety of the acid polysaccharide comprises at least one carboxyl group and/or a galatomannan polysaccharide.An improved electrophoretic technique for assaying the relative distribution of lactate dehydrogenase isoenzymes of the type wherein a sample to be assayed is applied to an electrophoretic gel and the electrophoretic gel is electrophoresed. The electrophoretic technique is characterized in that the above described electrophoretic gel is employed therein.

Abstract: A gas analyzer is disclosed which provides a dual channel capability for the simultaneous determination of the presence and concentration of two gases in a stream of sample gas and which has a single infrared source, a single sample cell, two infrared bandpass filters, and two infrared detectors.A separator between the filters and detectors prevents interchange of radiation between the filters. The separator is positioned by fitting it in a slot.

Abstract: An electrophoretic gel of the type comprising a polysaccharide. The electrophoretic gel is characterized in that it further comprises an acid polysaccharide and salts thereof, wherein the acid moiety of the acid polysaccharide comprises at least one carboxyl group.An improved electrophoretic technique for assaying the relative distribution of proteins of the type wherein a sample to be assayed is applied to an electrophoretic gel and the electrophoretic gel is electrophoresed. The electrophoretic technique is characterized in that the above described electrophoretic gel is employed therein.

Abstract: A gas discharge display having valve means comprising a pellet cooperating with a conical opening of a base plate of a display panel, the valve means allowing the continuous introduction of mercury vapor from a liquid mercury reservoir to the envelope of the display, but preventing the entrance of liquid mercury.

Abstract: An electrophoretic gel container. The device includes a base and a cover. The gel is adherently bound to a backing sheet. The cover is positioned to clamp the backing sheet between it and the base. The cover is spaced from the gel.