Abstract:
An apparatus for measuring the properties of a sample includes a sensor block with at least one sensor module whose housing contains a measuring chamber in contact with a sensor, the housing of the sensor module M including a mixing chamber for indirect measurement of a sample property, which chamber is placed upstream of the measuring chamber, and is connected with a sample channel and a reagent channel. Due to the modular design of the sensor block, the sample and reagent paths in the sensor block or sensor module may be kept short; along with the compact arrangement of mixing chamber and measuring chamber this permits the required sample and reagent volumes to be kept to a minimum.
Abstract:
An electrochemical measuring apparatus may be charged with an option of several media by providing a feeder part with the respective media connections, and by guiding a piece of pipe in a bore, which is sealed off and is movable relative to this feeder part. On its end facing away from a measuring chamber in the apparatus, the piece of pipe has a connection for additional media. Besides, it carries at least one circumferential bore which may be brought to coincide with at least one of the input openings into the bore connecting to the feed lines, by means of a relative motion - preferably controlled via a stepping motor - between the pipe piece and the above bore.
Abstract:
The measuring electrode to be checked is polarized cyclically with an alternating voltage and the maximum amplitude of the electrode current as occuring during cyclical polarization is directly used as a measure for the metrologically relevant condition of the electrode.
Abstract:
In a squeezed tube valve which comprises a valve block with a longitudinal groove to guide a flexible tube and a transverse groove for an electromagnetically actuated clamping bolt to shut off the tube, the crossing between the longitudinal and the transverse groove is rounded off at its edges, and the clamping force exerted by the bolt rises from zero according to an asymptotic rise function over the duration of the shutting action.
Abstract:
The measured values are calculated from the following equation: ##EQU1## in which X.sub.1, X.sub.i+1, X.sub.i+2 are three values of signals obtained from one electrode measured successively at equal intervals of time, namely after a latent time .tau. has elapsed.The time required for calibration and measurement in the course of a blood gas analysis can be substantially reduced by the consistent application of this procedure for obtaining the measured value for each calibration and measurement.
Abstract:
In order to simplify the performance of serial measurements by means of a measuring device for determining chemical parameters of an aqueous sample, with at least one symmetrical, ion-sensitive membrane being located between the sample and an electrolytic medium and the sample and the electrolytic medium being in contact with reference electrodes connected to an evaluation unit, a measuring element is provided which can be inserted into a measuring device and which has a sample chamber connected with a reference chamber via a bore. At least one measuring chamber is provided, which is separated from the sample chamber by a symmetrical, ion-sensitive membrane. The reference chamber and all measuring chambers contain electrolytic media into which are dipped the reference electrodes located in the measuring device.
Abstract:
In order to produce a small-volume flow measuring cell with good flow characteristics in a sensor device for determining the concentration of a substrate in a sample medium, comprising an enzyme electrode which is covered by a membrane and a reference electrode, both of which are in contact with the measuring cell, the proposal is put forward that the reference electrode be located outside of the membrane cover of the enzyme electrode and that the maximum extension of the flow measuring cell normal to the flow direction of the sample medium essentially be the same as the diameter of the sensitive layer of the enzyme electrode.
Abstract:
A feeding device with a feeder element for liquid or gaseous samples includes an automatic sample exchanger having sample vessels for the liquid or gaseous samples and openings between the sample vessels through which the feeder element is automatically shifted from the feed position for serial samples to an initial position in contact with a feed opening for calibrating or cleansing media.
Abstract:
A feeding device for introducing liquid or gaseous media into the analysis path of an analyzing apparatus includes a feeder element which cooperates in an initial position with a feed opening for calibrating or cleansing media and which may by brought into one or more sample feed positions. The feeder element is fastened by means of chain pins to a driven link chain which is guided by a guide pulley, the chain permitting the feeder element to be moved from the initial position and then tilted into a sample feed position upon contact of the feeder element with the guide pulley.
Abstract:
In its initial position an input opening of a sample input device provides a seal against a funnel element which is directly connected to a feed pipe delivering standard media and to a valve-controlled air supply, and which has a feed opening cooperating with the input opening. Thus, in the initial position of the sample input device, the input opening and the feed opening at the funnel element together are part of a closed path for the additional media required for measurement and cleaning purposes, which will simplify the overall design of the apparatus.