Abstract: A device for simultaneously measuring the level of particle and quantum radiation of a plurality of samples which includes a microplate having a plurality of wells for accommodating the plurality of samples. A plurality of light conductors, at least one for each well, is positioned to receive light from each well and forward it to a photodetector. When luminescence is determined, each well has only one conductor associated therewith and when liquid scintillation is determined, each well has two light conductors associated therewith.

Abstract: Process for carrying out an analytical determination of the presence of a substance by means of chemiluminescence, comprising employing fluorescein isothiocyanate (FITC) as a labelling agent, triggering a chemiluminescence reaction by adding an aqueous solution of sodium hypochlorite, and measuring the emission of light.

Abstract: A method and apparatus for automatically stabilizing drift in radiation measurements which employ a detector whose pulse amplitude corresponds to the energy absorbed by the detector, involves the use of a peak produced in the pulse amplitude spectrum by individual electrons. The peak is at the low energy end of the spectrum and is drift stable. It can be produced by for example a direct or indirect light source such as a light emitting diode, by the phosphorescence of e.g. a sodium iodide crystal used as a scintillation crystal in nuclear radiation measurement, or by spontaneous surface emission within the detector, which is suitably a photomultiplier. The apparatus includes a determination device to determine the position of the drift stable peak and a control device to control the detector in response to the output of the determination device.

Abstract: Disclosed is a method of and an apparatus for measuring the thickness of an object, usually a metal strip, by using a radiation beam and digital techniques and, more generally, a method of linearization of an exponential function which can be advantageously implemented by digital techniques. First, a counter is preset to a count corresponding to a predetermined magnitude of a value to be linearized. Then, a sequence of pulses whose number is representative of the value to be linearized is generated. The pulses of this sequence are counted so as to generate a signal each time the number of pulses counted corresponds to a standard value unit. Each signal so generated is used to modify by a predetermined count the count of the preset counter whereby, at the end of the sequence, the contents of the preset counter is representative of the value to be linearized.