摘要:
In a device for freezing milk, in particular colostrum (3), in a container (5) comprising a temperature control element (10), the temperature control element remains in the frozen milk.
摘要:
A method and test devices are used for field calibration of gas detectors. Brand new gas detectors are used as measurement standards in field calibration. The brand new gas detectors are in this case either employed directly as working standards, in which case the regular calibration by a reference standard is dispensed with, since the brand new gas detectors are always deemed to be sufficiently accurate. Alternatively, the brand new gas detectors are employed directly, namely as sufficiently accurately calibrated reference standards for the reference gas sensors acting as working standards and incorporated into the test device. In both cases the measured values of the gas sensors in the gas detectors to be calibrated are fed back to a sufficiently calibrated system, namely either directly to at least one brand new gas detector as a working standard or else to a reference sensor of a calibrated test device.
摘要:
The measuring arrangement contains a measuring cell and a reference cell, respectively, and microphones assigned to these cells, to which microphones an electronic evaluation circuit is connected and in which a subtraction of the signals of the microphones takes place, as well as a radiation source for applying a modulated signal to the measuring cell. The modulation frequency of the radiation source coincides with the resonant frequency of the measuring cell, and the measuring cell and the reference cell are open at at least one end to the gas to and/or aerosol to be detected. The measuring arrangement is used as smoke alarm, gas alarm, fire hazard alarm or as combined smoke and gas alarm, wherein each of the measuring cells is exposed to a radiation of a wavelength at which a relevant substance to be detected is absorbent and an opto-acoustic effect is produced as a result.
摘要:
Workpieces such as chips are removed from a receiving plane by a transfer unit, which carries them to a delivery plane. The workpieces are transported in two segments during two phases, each workpiece being deposited between the phases on an intermediate station arranged in the region of the feed path. The transfer unit has two working heads, which simultaneously transport one workpiece from the receiving plane to the intermediate station, and another workpiece from the intermediate station to the delivery plane. The workpiece can be pivoted or rotated at the intermediate station so that its lower surface can be grasped by the depositing head.
摘要:
Novel constituent materials for gas sensors detecting gaseous impurities in air contain metal oxides and catalyst additives. The materials are prepared by mixing a colloidal solution A of an oxide or a hydroxide of at least one metal selected from the groups Ib, IIa, IIb, IIIa, IIIb, IVa, IVb, Va, Vb, VIa, VIb, VIIb, VIII and the lanthanides and actinides of the periodic system with a solution B containing a salt or a complex compound of at least one metal selected from the group: lanthanum, chromium, manganese, iron, cobalt, nickel, copper, ruthenium, iridium, palladium, platinum, rhodium, osmium, silver, gold, antimony, bismuth, thorium, and irradiating the mixture thus obtained with light of the visible and ultraviolet spectral region in order to photochemically deposit the metal in finely distributed form on the metal oxide or metal hydroxide, respectively. The irradiated solution C thus obtained is processed without substantial change in the size of the colloidal particles of the metal oxide or metal hydroxide, respectively, in order to yield a solid D which subsequently is dried at a temperature which is higher than the intended operating temperature of the gas sensor by a maximum of 700.degree. C., particularly by a maximum of 500.degree. C. and preferably by a maximum of 300.degree. C.
摘要:
A test device, for checking the functioning capability of a gas-alarm annunciator, has a reservoir in which are located a target fluid and a carrier fluid. At least a part of the carrier fluid is present in a liquid aggregate state and the target fluid is at least partially dissolved in the liquid carrier fluid. An extraction device engages into the reservoir such that the target fluid can be extracted along with the liquid carrier fluid. The target fluid is constituted such that on reaching a coverage area of a properly functioning gas-alarm annunciator it will cause the gas-alarm annunciator to annunciate an alarm. A test system and a test method for checking a gas-alarm annunciator's functioning capability use such a test device.
摘要:
A method for automatically calibrating the control system of a device for providing domestic animals with a feed. The feed or the constituents thereof are discharged from supply containers (2.1-2.5) into a mixing container (1) which is connected to an area (3) from which the animals can take the feed. The time at which the feed or at least one of its constituents is added is predetermined in the control system and the time required for a certain quantity (volume and/or weight) of the feed or of a certain constituent of the feed to reach the mixing container (1) is determined automatically at intervals. In the event that the desired quantity is modified, the time which is predetermined in the control system is also modified.
摘要:
In a photo-acoustic gas sensor having a measuring cell, a lamp, a photo-diode, a gas-permeable diaphragm and a microphone, a device is included for monitoring the gas-permeable diaphragm and the microphone. The device is operated in an explosion-proof manner. Intentionally, for diagnostic purposes, an artificial pressure modulation is generated in the measuring cell. The pressure modulation is converted by the microphone into electrical monitoring signals which are amplified by an amplifier circuit and assigned to preset ranges by a microprocessor, for determining the functional condition of the diaphragm and the microphone, and of microphone sensitivity. Depending on the range assigned to the monitoring signal, an output signal is generated indicating a fault in the microphone and/or the diaphragm. In the event of long-term drift in microphone sensitivity, a calibration is performed in which gas concentration values are re-calculated and stored in an EEPROM. A heater wire can be used, for modulated heating to generate the pressure modulation.
摘要:
A photo-acoustic gas sensor for measuring a gas concentration, e.g., of an explosive gas, consists of a cylindrical sensor body (1) which includes a cylindrical measurement chamber (13) whose longitudinal axis extends perpendicular to the longitudinal axis of the cylindrical sensor body. Without changing the outer dimensions of the sensor body, the length of the measurement chamber can be changed in accordance with a desired measurement sensitivity and a desired measurement range. A light source (5) is disposed such that it irradiates the measurement chamber without irradiating a gas-permeable membrane (2), so that the membrane will not produce an interference signal. The gas sensor is rendered explosion-proof as the light source and a photo-diode (6) which monitors the light source are tightly sealed from the environment. Proper functioning of a microphone (4), the light source and the photo-diode are monitored by analyzing a background signal.
摘要:
A pyroelectric detector comprising a substrate, pyroelectric material distributed in a binder and applied to said substrate, and at least two electrically conductive electrodes, wherein the pyroelectric material comprises lithium tantalate consisting of single crystal particles, said lithium tantalate containing an amount of tantalum ranging from 25 to 75 mole % as tantalum pentoxide.