Abstract: With a view toward implementing a thermal controlling method for making reversible a temperature characteristic of a magnetic field generator using permanent magnets small in Hcj, a magnetic field generator whose temperature characteristic is reversible, using permanent magnets small in Hcj, and an MRI apparatus provided with such a magnetic field generator, there is provided a method for controlling the temperature of a magnetic field generator having a pair of disc-shaped permanent magnets whose magnetic poles opposite in polarity to each other are opposed to each other with spacing defined therebetween, and a yoke that forms return passes for magnetic fluxes of the permanent magnets, comprising the steps of raising the temperature from room temperature to a temperature higher than the room temperature, maintaining the temperature higher than the room temperature, and lowering the temperature from the temperature higher than the room temperature to the room temperature, whereby the temperature characteristi

Abstract: A method for disassembling a permanent magnet of a magnetic field generator where the permanent magnet has a plurality of magnetic blocks having a layout, includes pushing at least one non-magnetic spacer into the layout of the plurality of magnetic blocks. At least one magnetic block is displaced with the at least one non-magnetic spacer until the at least one magnetic block is pushed out of the layout of the plurality of magnetic blocks. When the at least one magnetic block is pushed out of the layout, the magnetic block is removed from the magnetic field generator. The steps of displacing and removing may be repeated until all of the magnetic blocks in the permanent magnet are replaced with a non-magnetic spacer. The magnetic blocks removed from the magnetic field generator may be demagnetized using known methods.

Abstract: An apparatus and method for shimming a magnetic field of a magnet in a volume of interest includes a nonmagnetic holder configured with an array of fluid containing pockets; and a solidified ferromagnetic fluid in each pocket of the array of fluid containing pockets, wherein the solidified ferromagnetic fluid is fabricated from a ferromagnetic fluid, a diluting liquid, a hardener, and an accelerator agent. The ferromagnetic fluid includes a carrier liquid, ferromagnetic particles, and a surfactant.

Abstract: A method for monitoring the stereoselectivity of at least one organic chemical reaction and the relative rate of at least one organic chemical reaction, wherein the reaction produces a product that can exist as at least two stereoisomers, the process comprising: providing a first reaction zone containing (1) an organic phase comprising the reaction mixture for producing the product and (2) an aqueous phase adjacent to, but substantially immiscible with the organic phase, the aqueous phase containing at least one first sensing agent that preferentially acts on a first stereoisomer in the product to produce a monitorable change, the product being diffusible into the aqueous layer (2).

Abstract: An apparatus and method for shimming a magnetic field of a magnet in a volume of interest includes a nonmagnetic holder configured with an array of fluid containing pockets; and a solidified ferromagnetic fluid in each pocket of the array of fluid containing pockets, wherein the solidified ferromagnetic fluid is fabricated from a ferromagnetic fluid, a diluting liquid, a hardener, and an accelerator agent. The ferromagnetic fluid includes a carrier liquid, ferromagnetic particles, and a surfactant.

Abstract: A method and apparatus for magnetic field drift compensation for a superconducting magnet system includes electrically coupling a micro-flux injection system to a secondary B0 superconducting coil in a secondary compensation circuit; magnetically coupling the secondary compensation circuit to the superconducting magnet via the secondary B0 superconducting coil; switching the micro-flux injection system on and off either thermally or magnetically to induce a first current from a flux coil of the secondary compensation circuit into the secondary B0 superconducting coil producing a secondary field to compensate magnet field drift of the superconducting magnet.

Abstract: A method and apparatus for magnetic field drift compensation for a superconducting magnet system includes electrically coupling a micro-flux injection system to a secondary B0 superconducting coil in a secondary compensation circuit; magnetically coupling the secondary compensation circuit to the superconducting magnet via the secondary B0 superconducting coil; switching the micro-flux injection system on and off either thermally or magnetically to induce a first current from a flux coil of the secondary compensation circuit into the secondary B0 superconducting coil producing a secondary field to compensate magnet field drift of the superconducting magnet.

Abstract: A method for bonding a plurality of magnetized blocks together includes providing at least two magnetized blocks, and bonding at least two magnetized blocks together using a door translatable in two orthogonal directions.

Abstract: A method of operating an imaging system having a main coil and a shield coil electromagnetically coupled to the main coil, wherein the method includes monitoring for an external environmental fluctuation of electromagnetism, and controlling current flow through the main and shield coils based upon the monitoring using a quench heater.

Abstract: A system and a method for magnetizing one of a plurality of substantially non-magnetized blocks disposed on a plate of a magnetic assembly used in an MRI device are provided. The system includes first and second arm portions operably coupled together. The system further includes a first electromagnetic coil disposed on a first end of the first arm portion, wherein the first electromagnetic coil is configured to generate a magnetic field that propagates from the first electromagnetic coil through at least one non-magnetized block and the plate and further through the first and second arm portions to magnetize the block.

Abstract: A magnetic field generator assembly includes a plurality of magnetic elements configured to collectively generate a magnetic field sufficient for diagnostic data acquisition and a non-magnetizable pane operationally connected to limit separation of one magnetic element from another magnetic element. Accordingly, the multi-element magnetic field generator is efficiently secured against deterioration often associated with prolonged exposure to high order magnetic fields.

Abstract: The present invention provides a method and apparatus for measuring the level of a liquid cryogen. The invention provides for use of a current source (52), a length, or multiple lengths, of superconducting filament (40) situated within a cryostat (1) containing a cryogenic fluid (2) and a voltmeter (51) for measuring the voltage drop across the filament (40). The invention further provides a method for using said apparatus.

Abstract: A magnetic field generator assembly includes a plurality of magnetic elements configured to collectively generate a magnetic field sufficient for diagnostic data acquisition and a non-magnetizable pane operationally connected to limit separation of one magnetic element from another magnetic element. Accordingly, the multi-element magnetic field generator is efficiently secured against deterioration often associated with prolonged exposure to high order magnetic fields.

Abstract: A method for positioning permanent magnetic blocks includes providing a plurality of magnetized blocks, positioning the magnetized blocks on a yoke in a row by applying a mechanical force at a first end of the row with a first clamping member and at a second end of the row with a second clamping member, and repositioning the blocks by reducing the mechanical force at the first end by moving the first clamping member away from the first end, and moving the second clamping member toward the second end.

Abstract: A product line of MRI systems includes a first MRI system including a first yoke and a plurality of magnet blocks forming a first central assembly disposed on the first yoke. The product line also includes a second MRI system including a second yoke, a plurality of magnet blocks forming a second central assembly disposed on the second yoke and shaped the same as the first central assembly, and a first set of magnet blocks mounted to the second yoke at a periphery of the second central assembly.

Abstract: A method of operating an imaging system having a main coil and a shield coil electromagnetically coupled to the main coil, wherein the method includes monitoring for an external environmental fluctuation of electromagnetism, and controlling current flow through the main and shield coils based upon the monitoring using a quench heater.

Abstract: The present invention provides a method and apparatus for measuring the level of a liquid cryogen. The invention provides for use of a current source (52), a length, or multiple lengths, of superconducting filament (40) situated within a cryostat (1) containing a cryogenic fluid (2) and a voltmeter (51) for measuring the voltage drop across the filament (40). The invention further provides a method for using said apparatus.

Abstract: The present invention relates to a method and system for adjusting a magnetic center field of a magnetic field generator in an MRI. One embodiment of the presenting invention relates to a magnetic field generator system having a magnetic center field. This embodiment comprises opposing posts and opposing yokes connected to the opposing posts, where at least one of the posts has a spacer. At least one permanent magnetic block is connected to at least one of the opposing yokes. Further, at least one spacer is formed in at least one of the posts, the yokes and/or the permanent magnetic block.

Abstract: A method for bonding a plurality of magnetized blocks together includes providing at least two magnetized blocks, and bonding at least two magnetized blocks together using a door translatable in two orthogonal directions.

Abstract: A method for positioning permanent magnetic blocks includes providing a plurality of magnetized blocks, positioning the magnetized blocks on a yoke in a row by applying a mechanical force at a first end of the row with a first clamping member and at a second end of the row with a second clamping member, and repositioning the blocks by reducing the mechanical force at the first end by moving the first clamping member away from the first end, and moving the second clamping member toward the second end.