Abstract: Nuclear magnetic resonance sensing apparatus includingone or more magnets operative to generate a static magnetic field in a region remote therefrom containing materials sought to be analyzed, the one or more magnets defining a longitudinal axis, the static magnetic field having a static field direction substantially perpendicular to the longitudinal axis and having generally uniform amplitude along the azimuth with respect to the longitudinal axis in the remote region;apparatus for generating a variable magnetic field in said remote region in a direction substantially parallel to the static magnetic field;apparatus for generating a radio frequency magnetic field in the remote region for exciting nuclei of the materials sought to e analyzed and having a radio frequency magnetic field direction substantially perpendicular to both the longitudinal axis and to the static field direction; andapparatus for receiving nuclear magnetic resonance signals from the excited nuclei and for providing an output indication o

Abstract: Nuclear magnetic resonance sensing apparatus including at least three magnets operative to generate a static magnetic field in a region remote therefrom containing materials sought to be analyzed, the at least three non-conductive permanent magnets being arranged along a longitudinal axis in side to side arrangement and having generally uniform cross sections, which, when joined, together define a circular cross section, the overall length of said at least three magnets along said longitudinal axis being greater than their dimensions perpendicular to said longitudinal axis and greater than twice the radial separation of said remote region and said longitudinal axis, the at least three magnets being magnetized in magnetization directions extending generally perpendicular to the longitudinal axis, at least one of the at least three magnets having a magnetization direction opposite to the magnetization direction of at least another one of the at least three magnets, the static magnetic field having a static fiel

Abstract: A split cycle cryogenic cooler system of the Stirling split type comprises a compressor which is positioned in a sealed casing, the drive for the compressor being constituted by an electro-motor positioned outside the casing, magnetic torque coupling transmitting rotational movement from the motor to the piston of the compressor via a crankshaft.

Abstract: In order to control the passive motion of the pneumatically driven displacer in a cryogenic cooler system of the split cycle type, the refrigerant gas is forced to flow through a narrow passage within the pneumatic pillow in a manner that the gas during that passage is in viscous friction with the wall of the passage.

Abstract: Apparatus for producing linear motion comprising a coil defining an electromagnetic field across a gap; and a permanent magnet disposed within the magnetic field in the gap and arranged to be driven in motion by the magnetic field, the permanent magnet being configured such that its axis of magnetization lies along its smallest dimension.

Abstract: Apparatus for producing linear motion comprising a coil defining an electromagnetic field across a gap; and a permanent magnet disposed within the magnetic field in the gap and arranged to be driven in motion by the magnetic field, the permanent magnet being configured such that its axis of magnetization lies along its smallest dimension.

Abstract: Hair cutting apparatus comprising a housing; an AC electromagnet fixed in the housing and defining a gap; at least one permanent magnet disposed for reciprocating motion in the gap; a mounting member pivotally mounting the at least one permanent magnet about an axis fixed in the housing; and apparatus for drivingly connecting the mounting member to a hair cutting head for reciprocal motion of cutting apparatus in the cutting head in response to reciprocating motion of the at least one permanent magnet in the gap.

Abstract: A device and method for obtaining an identification pattern of polished gemstones. The device comprises, in combination, means for holding the gemstone in a reproducible position, means for creating a collimated parallel light beam, a lens for projecting a pattern obtained by reflecting the collimated parallel light beam from the gemstone onto a plane recording medium facing a plane reference surface of the gemstone. The distinctive pattern may be projected onto the plane recording medium via beam-splitting means. The light used can be white, or monochromatic. Polarized light may be used. Rotation of the pattern about the reference point of the optical axis provides a pattern which may be evaluated automatically.

Abstract: An intruder detection system comprising a line adapted to be located substantially at ground level and consisting of an elongated high permeability magnetic core on which is wound a coil in the form of successive sections of respectively opposite winding handednesses, a high gain low noise amplifier coupled to the line and a detector coupled to the amplifier and adapted to be coupled to an alarm system.