Abstract: In order to reduce the water content in piezoelectric GaPO.sub.4 crystal elements the proposal is put forward that each GaPO.sub.4 crystal element should be cut in its entirety from one uniform growth zone of a GaPO.sub.4 raw crystal bar and should not contain any zone boundaries, and that the piezoelectric GaPO.sub.4 crystal elements should be treated with a dehydrating solution, until an infrared coefficient of .alpha.<1.5 cm.sup.-1 is obtained at a wavelength in the vicinity of 2.0 .mu.m.

Abstract: A transducer comprising a flexible piezoelectric layer as a sensor element for measuring mechanical quantities in hollow bodies, above all pressures in pipes, the opposite sides of this layer being bonded to electrically-conductive contact layers and being connectable via leads to a display and evaluation unit. In order to achieve a high temperature stability in such transducers and to make them suitable for use at temperatures exceeding 80.degree. C., the piezoelectric layer is proposed to consist of wurtzite or sphalerite. One of the electrically-conductive contact layers can be of some heat-resistant, flexible supporting material, for instance flexible metal foil, such as Cu-Be foil, or a sheet of plastic, one or both of whose sides are metallized, and the other electrically-conductive contact layer can be a metal coating applied by evaporation.

Abstract: A device for equilibrating small quantities of a liquid reagent or a test solution with a gas-containing liquid or a gas in which at least part of the passage of the reagent leads through a hollow space that is separated by a permeable wall from a gas chamber which is closed, except for an inlet and an outlet opening, and which may be charged with the gas or gas-containing liquid. In order to ensure good mixing of the test liquid during equilibration, the hollow space carrying the liquid is configured as a tube or hose with one or more helical sections inside the gas chamber whose walls are permeable to the gas.

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: A pressure measuring device is provided with a change-over valve connecting the pressure sensor either with the pressure to be measured or with a reference pressure. The change-over valve is actuated by a separate control pressure and will protect the pressure sensor from the influence of the pressure medium to be measured in the spring-loaded idle position of the valve.

Abstract: A transducer with a flexible sensor element for measurement of mechanical values, at least one flexible piezoelectric sensor element being provided for piezoelectrical or capacitive measurement, the opposite surfaces of the sensor element being at least partially connected to electrically leading contact surfaces.

Abstract: In a pressure indicator for measurement of hot pressure mediums, comprising an indicator housing adjustable to an opening in an enclosure for the medium to be measured, a measuring element, and a power train comprising a diaphragm connected to the housing and a power transmission element for connecting the diaphragm to the measuring element, a narrow gap is provided for between at least one of the parts of the power train on the one side and the housing on the other side, and that part of the housing being adjacent the gap is substantially in direct heat conducting connection with the enclosure for the medium when the indicator is adjusted to the opening therein.

Abstract: An analyzing apparatus for measuring samples of a liquid has feeding means for feeding the samples contained in sample containers to a subsequent sample conduit, the feeding means having a substantially funnel shaped filling mouth serving for fastening sample containers of very different shapes, such as syringes, pipettes or capillary tubes, and the dimensions of the outlet opening thereof varying within wide limits. A cleaning device can be used, which has a washing body which during the cleaning operation, together with the funnel shaped filling mouth, defines an annular gap adapted to match the form of the filling mouth and is providable with a cleaning medium.

Abstract: A transducer device for measuring the internal pressure in pipes, comprises two housing parts which are articulately connected with one another by a connecting element and adapted to be fixedly mounted on the pipe by means of a clamping device. Each housing part contains at least one measuring element with a bipolar take-off of the test signals. At least one pole of each take-off is electrically conductingly connected with a part of the connecting element which is electrically insulated relative to the other pole and the connecting element comprises connection terminals for the further conduction or transmission of the test signals. The other pole is potentially in direct connection with the pipe.

Abstract: A transducer comprising a piezoelectric measuring sensor element for measurement of mechanical values on hollow bodies, especially of the pressure distribution within pipes, the piezoelectric sensor element being a flexible piezoelectric film, the opposite surfaces of the film being in connection with electrically leading contact surfaces, and the measuring sensor element being at least partially and at least indirectly closely joinable to the surface of the hollow body.

Abstract: A transducer for measuring the internal pressure in pipes, preferably injection pipes of diesel engines by determination of pipe deformations, comprises a rigid housing enclosing the pipe in which the pressure is to be measured, and at least one elastic sensor element arranged inside the housing and adjacent to at least a part of the circumference of the pipe. The sensor element and the housing are detachably mounted on the pipe and between the housing and the sensor element there is arranged an endorsing element elastically forcing the sensor element against the pipe whereby deformations of the pipe are transmitted frictionally to the sensor element.

Abstract: A multi-wire oxygen electrode and method of manufacturing the same, said electrode having a reactive electrode surface formed by a glass electrode tip having an end surface and a number of electrode wires are distributed in the end surface of the electrode tip along a circle. The cross-sectional surfaces of said electrode wires are freely exposed in such end surface and the electrode wires are fused in the electrode tip and electrically conductively connected with a cathode wire arranged in a glass sleeve. There is provided a substantially semi-spherical shaped support surface having an apex, said support surface being coaxially arranged with respect to the electrode tip, and said cathode wire being held in the electrode tip at the apex of the support surface.

Abstract: A multi-wire oxygen electrode and method of manufacturing the same, said electrode having a reactive electrode surface formed by a glass electrode tip having an end surface and a number of electrode wires are distributed in the end surface of the electrode tip along a circle. The cross-sectional surface of said electrode wires are freely exposed in such end surface and the electrode wires are fused in the electrode tip and electrically conductively connected with a cathode wire arranged in a glass sleeve. There is provided a substantially semi-spherical shaped support surface having an apex, said support surface being coaxially arranged with respect to the electrode tip, and said cathode wire being held in the electrode tip at the apex of the support surface.