Abstract: A ceramic superconductor is made by consolidating a plurality of metals and a chalcogen and applying a magnetic field during the consolidation operation.

Abstract: A medical nuclear magnetic resonance system is provided with a primary field magnet assembly having a ferromagnetic frame. The system resists field variations caused by coil movement and confines the field within the frame.

Abstract: An apparatus and method for processing a first electrical signal having a frequency interval I containing information, and increasing the signal-to-noise ratio thereof utilizes a mixer for shifting the frequencies of the first signal in the interval I to an interval I.sub.s. A plurality of filters, coupled in parallel, to the mixer pass, respectively, only frequencies in subintervals of I.sub.s, which are mutually disjoint. A second embodiment utilizes a plurality of mixers which shift, respectively, mutually disjoint subintervals of I such that their left end points are substantially equal. A plurality of filters, coupled, respectively, to the mixers, pass, respectively, only those frequencies in the shifted subintervals. Preferably, the frequency intervals passed by the filters in both embodiments are equal in bandwidth, and have no gaps therebetween.

Abstract: An NMR scanner apparatus uses a permanent magnet comprised of an assembly of magnetic material formed of a substantial number of low energy permanent magnetic elements producing magnetic flux and arranged in at least one row of columns. A frame of magnetically soft material provides a return path for the magnetic flux and provides a surface from which the columns of magnetic elements extend. A flux concentrator plate is disposed adjacent to a surface of the assembly and recessed a sufficient distance from the edge of the assembly to inhibit the loss of magnetic flux. The flux concentrator plate and the frame sandwich the magnetic assembly therebetween. A pole piece consisting of a soft magnetic material is disposed adjacent to a surface of the flux concentrator plate. The pole piece defines a scanning area substantially smaller than the area of the adjacent surface of the flux concentrator plate such that the pole piece exhibits parallel lines of magnetic flux for inducing polarization in living tissue.

Abstract: An apparatus for nuclear magnetic resonance scanning and imaging which employs a primary magnetic field, an rf field, and a detector for detecting a nuclear magnetic resonance signal, the primary magnetic field being produced by an assembly of relatively low energy flux magnetic material combined with an assembly of relatively high energy flux magnetic material. The magnetic flux of the relatively low energy flux magnetic material is concentrated in a magnetic flux conductor means which is in turn combined with the magnetic flux of the relatively high energy flux magnetic material and is concentrated at a pole piece.