Improvements in the sensitivity and reproducibility of nephelometric endotoxin determinations using endotoxin-activated enzyme from Limulus amebocyte lysate are achieved by contacting endotoxin-coagulated lysate with an ionic surface active suspending agent, generally a mixture of detergent and suspending agent. Instrumentation improvements further enhance results.

A method of determining the oxygen content of a liquid metal is disclosed and comprises measuring the EMF across an electrolytic cell in which one of the electrodes comprises the liquid metal and the other electrode is a reference electrode of a mixture comprising a known concentration of one of the metals selected from the group of gallium, indium and tin, and an oxide of said metal with the mixture being liquid at the temperature of measurement, and the electrolyte is an oxygen ion conductive,...

A level determining-device wherein a chain is suspended from a mechanism which is adapted to raise and lower the chain. Means are provided for sensing the weight of a part of the chain hanging freely from the mechanism, whereby the length of the freely hanging part, and hence a desired level, can be determined.

Article orientation determining apparatus is exemplified in apparatus for determining if the tip ends of corn cobs are leading or trailing as they advance toward a kernel cutter head. The cobs pass between a column of sequentially pulsed radiation emitters and corresponding detectors which scan successive slices of the article and develop binary data indicative of the number of emitters that are unblocked during each scan. A computer uses the data to determine orientation and provides signals fo...

An imbalance determining system for a dynamic balancing machine for two-plane balancing of rotary elements such as vehicle wheel-and-tire assemblies includes a chuck and spindle mounted in a spindle housing in vibration-isolation orientation on a machine base. The rotary element is brought to speed by one or more drive mechanisms which are mounted on the machine base to move between a driving orientation in contact with the rotary element and a storage orientation out of contact with the rotary ...

A device is disclosed for determining ion activity in liquid solutions by the use of electrodes and a capillary bridge which promotes ionic migration between the electrodes. The bridge is formed of a porous material layer into which liquid solutions are absorbed, a bottom nonporous layer between the electrodes and the porous material, and a top nonporous layer on the other side of the porous material. Preferably, the three layers are apertured at each electrode to provide wells for receiving dro...

Discrimination of long range targets from short range targets is provided by generating a vertical dipole beam and a narrow uni-directional horizontal beam which may be steered. Targets in the dipole beam are short range targets whose acoustic signals arrive at angles to the horizontal plane, whereas long range targets are those in the horizontal beam, since acoustic signals from long range targets come in on the horizontal plane.

Cholesterol is determined utilizing cholesterol oxidase, and optionally cholesterol esterase to cleave bound cholesterol, in the presence of peroxidase, p-amino-phenazone, a surface-active agent and phenol, the improvement comprising employing an alkanol of up to 4 carbon atoms in the test composition or sample to substantially overcome test error and deviations due to turbidity formation.

An improved position determining device using a delay line with energy absorptive terminations at the ends thereof and having a driver transducer coupled to the delay line for producing a traveling wave on the line and a first receiver transducer coupled to the delay line at the distance to be determined. A second receiver transducer, also coupled to the delay line, is displaced from the first receiver transducer by a distance preferably substantially equal to one-quarter wavelength of the trave...

An apparatus for use in determining the peripheral vision extent of a patient's eye includes a contact lens type construction detachably fitted to the eye having multiple optical fibers each extending to an illuminating source. Upon illumination of a selected fiber, light is directed into the eye and the patient's response noted. The fibers are distributed so as to extend radially outwardly on the lens and thus a patient's responses provide a so-called "map" of peripheral vision extent.