摘要:
An inner and outer cylindrical cathode are concentrically positioned about a vertical center axis. Vertical anode electrodes extend parallel to the center axis and are symmetrically arranged around the inter-cylinder space between the cathodes. The ends of the anode wires are supported by a pair of insulator rings mounted near the top and bottom of the cathode cylinders. A collection voltage applied to each anode wire for establishing an inward radial E field to the inner cathode cylinder and an outward radial E field to the outer cathode cylinder. The anode-cathode assembly is mounted within a housing containing a conversion gas. A radioactive sample is inserted into the inner cathode which functions as a tubular, deep well radiation window between the sample environment and the conversion gas environment. A portion of the gamma radiations passing through the inter-cylinder region interact with the conversion gas to produce free electrons which are accelerated by the E fields and collected on the anode wires. The extremely small diameter of the anode wires intensifies the electric fields proximate each wire causing avalanche multiplication of the free electrons resulting in a detectable charge pulse.
摘要:
A multiple single use optical sensor includes a series of continuous sensor stripes deposited on a substrate web. At least one sample chamber is adapted to extend transversely across a discrete portion of the series of sensor stripes to facilitate analysis of a sample disposed therein. The sample chamber may be moved, or additional sample chambers provided to enable subsequent measurements of additional samples at unused discrete portions of the sensor stripes. The continuous nature of the sensor stripes provides consistency along the lengths thereof to enable calibration data obtained from one discrete portion of the sensor stripes to be utilized for testing an unknown sample an other discrete portion of the sensor stripes. This advantageously eliminates the need for any particular discrete portion of the sensor stripes to be contacted by more than one sample, for improved sensor performance.
摘要:
Disclosed is an apparatus for a method for assuring the quality of the results obtained from a blood gas analyzer. The apparatus comprises a device for storing blood gas quality control reagent comprising a first variable volume, gas impermeable container for receiving the reagent. The reagent is stored exclusively in the liquid phase therein. A valved exit passageway emanates from the container which container is situated in a second container surrounding the first, a space being present therebetween and a compressed gas situated in the space. Upon opening the valve, the compressed gas decreases the volume of the first container and reagent is expelled through the exit passageway. The present device is uneffected by changes in ambient temperature since the reagent is stored exclusively in the liquid phase. The device is reusable since a portion of the reagent may be expelled without contamination of the remaining contents. Further, a method is disclosed for storing blood gas quality control reagent such that it is stored exclusively in a liquid phase.
摘要:
Apparatus for controlling the temperature of an open liquid body when actual measurement of that temperature is not possible. A thermal analog of the liquid body, which is exposed to the same heating or cooling source as the liquid body, is incorporated into a sensor which provides controlling feedback to the heating or cooling source. The sensor, which is disposed in the atmosphere which surrounds or flows by the liquid body, includes a dry element and a wet wick, body of which are in thermal contact with a temperature sensing element. The dry element senses the temperature of the atmosphere and the wet wick has a cooling effect on the sensing element that is related to the rate of evaporation of liquid from the body. This sensor is advantageously employed in a system for regulating the temperature of a reagent film on a microscope slide.
摘要:
Multi-analyte reference solutions having a stable partial pressure of oxygen (pO2) in zero headspace packaging and methods for preparing such solutions are disclosed. The solutions have long shelf and use lives when stored at room temperature and are packaged in laminated foil containers having low or no oxygen reactivity. Access devices are also disclosed.
摘要:
A multiple single use optical sensor includes a series of continuous sensor stripes deposited on a substrate web. At least one sample chamber is adapted to extend transversely across a discrete portion of the series of sensor stripes to facilitate analysis of a sample disposed therein. The sample chamber may be moved, or additional sample chambers provided to enable subsequent measurements of additional samples at unused discrete portions of the sensor stripes. The continuous nature of the sensor stripes provides consistency along the lengths thereof to enable calibration data obtained from one discrete portion of the sensor stripes to be utilized for testing an unknown sample an other discrete portion of the sensor stripes. This advantageously eliminates the need for any particular discrete portion of the sensor stripes to be contacted by more than one sample, for improved sensor performance.
摘要:
Provided is an optical sensor including a support and a detection layer, wherein the detection layer includes: (a) a luminescent material wherein the luminescence intensity of the luminescent material varies as the amount of an analyte varies; (b) a reflective material having a highly efficient reflectance of the wavelengths of excitation and of emission of the luminescent material; and (c) a polymeric binder to support and hold together the luminescent material and the reflective material. Such an optical sensor can be advantageously used in the detection of gaseous, ionic, and nonionic analytes in highly scattering samples. Also provided are methods for the manufacture of such optical sensors.
摘要:
Method and apparatus for staining biological specimens by forming a film of staining reagents on the surface of the specimen containing slide. Heating means raises the temperature of the staining reagents on the slide. The temperature of the reagent film is determined, and a feedback signal to the heating means accurately maintains the temperature of the film within a predetermined range.
摘要:
A sample introduction device is provided that is particularly useful in the critical care environment for the anaerobic withdrawal of small volumes of arterial blood from a sample collection syringe and introduction thereof into a sample chamber of a sensor for analysis. The sample introduction device includes a Luer fitting adapted to mate an outlet of the container in a concentric orientation with an input aperture of the sample chamber. A tubular probe is adapted for concentric placement with both the outlet and inlet aperture, with a first end thereof extending into the syringe and a second end adapted for attachment to an air supply. The probe has a predetermined diameter sufficient to provide an annular clearance between the probe and each of the outlet and inlet aperture. A predetermined volume of air is injected through the probe into the container to displace a predetermined volume of sample therefrom, through the annular clearance into the sample chamber. Injecting air into the syringe through the probe to displace the sample therefrom, rather than drawing the sample into the probe, advantageously reduces or eliminates the need for washing the interior of the probe to relatively reduce the use of wash reagents.
摘要:
A liquid permeable metallic coating is utilized in conjunction with a fluorescence based optical sensor. The metallic coating is deposited directly on, and is in physical contact with, the sensing membrane. The metallic coating does not require an intervening substrate layer or other components. When light from a light source is shone through the substantially light transmissive substrate onto the sensing membrane, the metallic overcoating reflects back the excitation light as well as the fluorescence light generated by the sensor such that substantially no light reaches the sample where the light may be scattered and/or absorbed by the sample. Accordingly, the accuracy and repeatability of the sensor is improved while the cost and production times associated with manufacturing the sensor are minimized.