Abstract: A method for determining a shape of particles in a distribution with reduced measuring and analyzing complexity includes detecting the number of particles, measuring and storing a particle chord length for each particle as a measurement for particle size and measuring at least first and second distributions of the particle size from the particle chord length measured for each particle. The first distribution is based on a first quantity type, the second distribution is based on a second quantity type and the quantity types correspond to different powers of the particle size. A first distribution parameter, corresponding to a cumulative or density distribution, of the first distribution is set into a distribution parameter ratio with a second distribution parameter, corresponding to a cumulative or density distribution, of the second distribution. An aspect ratio is determined from the distribution parameter ratio as a value characterizing the shape of the particles.

Abstract: A method for determining a shape of particles in a distribution with reduced measuring and analyzing complexity includes detecting the number of particles, measuring and storing a particle chord length for each particle as a measurement for particle size and measuring at least first and second distributions of the particle size from the particle chord length measured for each particle. The first distribution is based on a first quantity type, the second distribution is based on a second quantity type and the quantity types correspond to different powers of the particle size. A first distribution parameter, corresponding to a cumulative or density distribution, of the first distribution is set into a distribution parameter ratio with a second distribution parameter, corresponding to a cumulative or density distribution, of the second distribution. An aspect ratio is determined from the distribution parameter ratio as a value characterizing the shape of the particles.

Abstract: A method and an apparatus for determining the particle content of a particle stream using a source of light and two receivers arranged offset from one another in the flow direction of the particle stream. The receivers provide an electrical signal to an evaluation unit as a function of the radiation intensity which they receive, and this signal makes possible a determination of the flow velocity and particle size. Coincident passage of two particles is indicated by a pulse occurring in the signal due to a “roof collapse” in the pulse caused by a weakening of the radiation intensity as the particles pass a receiver.

Abstract: A method and an apparatus for determining the particle content of a particle stream using a source of light and two receivers arranged offset from one another in the flow direction of the particle stream. The receivers provide an electrical signal to an evaluation unit as a function of the radiation intensity which they receive, and this signal makes possible a determination of the flow velocity and particle size. Coincident passage of two particles is indicated by a pulse occurring in the signal due to a “roof collapse” in the pulse caused by a weakening of the radiation intensity as the particles pass a receiver.

Abstract: A measuring head for determining particle size in transparent media, comprising a measuring head body which has an opening for an optical measuring point with two measuring windows, consisting of an illuminating device and a light receiving device which is connected to an opto-electronic converter device. A rinsing device is used to clean the optical measuring point. The windows can be reliably prevented from becoming fouled or wetted by particles contained in the particle flow, enabling optical permeability of the measuring point and avoiding false measuring values. The rinsing device has a rinsing medium source, a channel extending to the opening inside the measuring head body for delivery of a rinsing medium and at least one discharge opening near the opening, which extends perpendicularly to and directly in front of the measuring windows. At least one defined rinsing jet is spread over the surfaces of the measuring windows.

Abstract: In an exemplary embodiment, the control circuit for controlling filament current to maintain x-ray tube voltage at a set point value is disabled near the beginning of an x-ray exposure by the cut-off of filament current to provide a falling load characteristic as a function of time. During the cooling of the x-ray tube filament, the x-ray tube voltage is maintained near its set point value by the timed switching of taps of a variable-ratio transformer to change the input voltage to the x-ray tube high voltage transformer, and by the coordinated changing of the loading of the primary circuit of such high voltage transformer, the control circuit for maintaining x-ray tube voltage at the set point value thereafter being placed in control of the filament current for the remainder of the x-ray exposure.