Abstract: The invention relates to a transmitting system for the generation of ultrasonic waves for testing materials, comprising a controllable signal generator and an ultrasonic transducer, wherein the signal generator and the ultrasonic transducer are arranged in the immediate vicinity of one another, in order to provide a transmitting system for ultrasonic testing which has higher effectiveness and lower manufacturing costs than known transmitting systems.

Abstract: A device is disclosed for measuring light scatter by particles (3) suspended in a carrier medium with a view to ascertaining the density, size or size distribution of the particles. The device comprises: at least one light source (8) which directs light onto a light-scattering center (2) in the carrier medium with the suspended particles (3); a receiver (4) to pick up a portion of the scattered light from the light-scattering center; and an evaluating device connected downstream of the receiver (4). The invention provides for an elongated detection chamber bounded radially around its central axis by the wall of a housing (1) which also acts as a duct for the through-flowing carrier medium with the suspended particles (3). Each light source (8) is mounted on the wall of the housing (1) and points toward the central axis of the detection chamber.

Abstract: Apparatus for the bidirectional transfer of information comprises in each case: at least one rotating component (1); a further component (2); receivers (4, 5) on the respective components (1, 2), said receivers facing one another in groups on the axis of rotation (6) of the rotating component (1); and transmitters (7, 8) fitted on the components (1, 2) eccentrically with regard to the axis of rotation and directed towards the corresponding receivers (4, 5).

Abstract: A method and apparatus for monitoring layer erosion in a dry-etching process. The apparatus has a first electrode that is electrically connected to a substrate to be etched, as well as a second electrode that is located above the first electrode. Both electrodes are situated inside a process chamber. An optical photometer is positioned outside of the process chamber and directed onto the substrate in the process chamber. Signals received from the optical photometer are amplified by an electrical circuit and are edited and displayed with a Fourier transformation. The etching process can be automatically interrupted when received periodic signals having essentially constant amplitude and frequency undergo a significant change during the etching process of the upper layer. That is, they are received as signals signficantly deviating from one another, this being identified by the electrical circuit as the passage from one layer to another layer of the substrate during the dry-etching process.

Abstract: A device for mass transfer between fluids through a diaphragm unit comprising a pair of diaphragms with a diaphragm support therebetween, in which the diaphragm unit is a pleated package supported in a case, with the pleats and support defining a plurality of separate flow paths, and the diaphragm unit is shaped in a direction transverse to the longitudinal axis of the pleats with a zig zag or sine-wave shape, so that a compound zig zag or sine-wave shape results for the unit.

Abstract: Apparatus for mass transfer between fluids, comprises two permeable membranes with a porous membrane support sandwiched therebetween, all pleated together with an accordian pleat to form a pleat package, and sealed in a casing to define three flow channels from one end of the casing to the other, to form a filter having a large filter area in a minimum amount of space for use as a dialyzer or as an ultrafilter in the treatment of blood. By selection of different membrane materials, the apparatus may also be used for oxygenation of blood, and three different fluids, including both gases and liquids, may be treated.