Patents by Inventor Thomas de Swiet

Thomas de Swiet has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7560922
    Abstract: The NMR device with a magnet utilizes a composition exhibiting a desired value of magnetic susceptibility, wherein the composition comprises a metal ion selected from the group consisting of Gd+3, Fe+3 and Mn+2 and an amorphous material using a ligand or chelating agent to solubilize the metal ion throughout the amorphous material, wherein the magnetic susceptibility of the composition exhibits a desired value at cryogenic temperatures such as nearly zero susceptibility at temperatures at or below 77 K.
    Type: Grant
    Filed: September 29, 2008
    Date of Patent: July 14, 2009
    Assignee: Varian, Inc.
    Inventors: Thomas M. Barbara, Thomas de Swiet
  • Publication number: 20090021259
    Abstract: The NMR device with a magnet utilizes a composition exhibiting a desired value of magnetic susceptibility, wherein the composition comprises a metal ion selected from the group consisting of Gd+3, Fe+3 and Mn+2 and an amorphous material using a ligand or chelating agent to solubilize the metal ion throughout the marphous material, wherein the magnetic susceptibility of the composition exhibits a desired value at cryogenic temperatures such as nearly zero susceptibility at temperatures at or below 77 K.
    Type: Application
    Filed: September 29, 2008
    Publication date: January 22, 2009
    Inventors: Thomas M. Barbara, Thomas de Swiet
  • Patent number: 7476330
    Abstract: An composition exhibiting a desired value of magnetic susceptibility, which can be used to fabricate components in an NMR device, and method thereof, wherein the composition comprises a metal ion selected from the group consisting of Gd+3, Fe+3 and Mn+2 and an amorphous material using a ligand or chelating agent to solubilize the metal ion throughout the marphous material, wherein the magnetic susceptibility of the composition exhibits a desired value at cryogenic temperatures such as nearly zero susceptibility at temperatures at or below 77° K.
    Type: Grant
    Filed: September 24, 2003
    Date of Patent: January 13, 2009
    Assignee: Varian, Inc.
    Inventors: Thomas M. Barbara, Thomas de Swiet
  • Patent number: 7068034
    Abstract: Nuclear magnetic resonance (NMR) systems and methods employing squashed (transversely-elongated) sample vessels (sample tubes or flow cells) for holding liquid NMR samples, and matching squashed saddle-shaped RF coils allow reducing sample and/or coil losses and increasing the RF circuit quality factors (Q). In a present implementation, the RF coils and sample vessels have rectangular cross-sections. Rounded (e.g. ellipsoidal) or other squashed cross-sections may also be used. The coil corresponding to the highest sample losses is positioned such that the magnetic field generated by the coil is along the major axis of the sample vessel. Squashed sample vessels may also be used with conventional circular coils, particularly for low-temperature measurements where sample losses dominate.
    Type: Grant
    Filed: October 19, 2004
    Date of Patent: June 27, 2006
    Assignee: Varian, Inc.
    Inventor: Thomas de Swiet
  • Patent number: 6917201
    Abstract: Nuclear magnetic resonance (NMR) systems and methods employing squashed (transversely-elongated) sample vessels (sample tubes or flow cells) for holding liquid NMR samples, and matching squashed saddle-shaped RF coils allow reducing sample and/or coil losses and increasing the RF circuit quality factors (Q). In a present implementation, the RF coils and sample vessels have rectangular cross-sections. Rounded (e.g. ellipsoidal) or other squashed cross-sections may also be used. The coil corresponding to the highest sample losses is positioned such that the magnetic field generated by the coil is along the major axis of the sample vessel. Squashed sample vessels may also be used with conventional circular coils, particularly for low-temperature measurements where sample losses dominate.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: July 12, 2005
    Assignee: Varian, Inc.
    Inventor: Thomas de Swiet
  • Publication number: 20050077900
    Abstract: Nuclear magnetic resonance (NMR) systems and methods employing squashed (transversely-elongated) sample vessels (sample tubes or flow cells) for holding liquid NMR samples, and matching squashed saddle-shaped RF coils allow reducing sample and/or coil losses and increasing the RF circuit quality factors (Q). In a present implementation, the RF coils and sample vessels have rectangular cross-sections. Rounded (e.g. ellipsoidal) or other squashed cross-sections may also be used. The coil corresponding to the highest sample losses is positioned such that the magnetic field generated by the coil is along the major axis of the sample vessel. Squashed sample vessels may also be used with conventional circular coils, particularly for low-temperature measurements where sample losses dominate.
    Type: Application
    Filed: October 19, 2004
    Publication date: April 14, 2005
    Inventor: Thomas de Swiet
  • Patent number: 6812703
    Abstract: An NMR probe comprises a resonator formed of two separate conducting loops disposed on opposite sides of the sample, where one loop is driven and the other floats in a preferred operating mode. Slotted shields are disposed coaxially within said loops and outside the sample with slots aligned with gaps between the loops.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: November 2, 2004
    Assignee: Varian, Inc.
    Inventors: Thomas de Swiet, Knut G. Mehr
  • Publication number: 20040113617
    Abstract: An NMR probe comprises a resonator formed of two separate conducting loops disposed on opposite sides of the sample, where one loop is driven and the other floats in a preferred operating mode. Slotted shields are disposed coaxially within said loops and outside the sample with slots aligned with gaps between the loops.
    Type: Application
    Filed: December 17, 2002
    Publication date: June 17, 2004
    Inventors: Thomas de Swiet, Knut G. Mehr
  • Publication number: 20040108852
    Abstract: Nuclear magnetic resonance (NMR) systems and methods employing squashed (transversely-elongated) sample vessels (sample tubes or flow cells) for holding liquid NMR samples, and matching squashed saddle-shaped RF coils allow reducing sample and/or coil losses and increasing the RF circuit quality factors (Q). In a present implementation, the RF coils and sample vessels have rectangular cross-sections. Rounded (e.g. ellipsoidal) or other squashed cross-sections may also be used. The coil corresponding to the highest sample losses is positioned such that the magnetic field generated by the coil is along the major axis of the sample vessel. Squashed sample vessels may also be used with conventional circular coils, particularly for low-temperature measurements where sample losses dominate.
    Type: Application
    Filed: December 9, 2002
    Publication date: June 10, 2004
    Inventor: Thomas de Swiet
  • Patent number: 6667674
    Abstract: A birdcage resonator has a pair of conductor rings separated from each other along a central axis and a plural number of axially disposed conductor rungs, which extend between the rings and are evenly spaced around the central axis. Each of the rungs has a sectional shape with thickness or a radial extension comparable to or greater than its width or its azimuthal extension. Measures of the width and thickness of the rungs may be determined by using them as parameters to calculate the values of Q factor from an analytical procedure to locate parameter value ranges corresponding to maximal Q. Geometric calculations for filling factor yield ranges of parameters providing for compromise parameter values. Saddle coils have been found to exhibit similar enhancement of Q with radially oriented conductor cross section.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: December 23, 2003
    Assignee: Varian, Inc.
    Inventors: Thomas de Swiet, Wai Ha Wong, Marco Romo, James Finnigan, Sean Burns
  • Publication number: 20030193380
    Abstract: A birdcage resonator has a pair of conductor rings separated from each other along a central axis and a plural number of axially disposed conductor rungs, which extend between the rings and are evenly spaced around the central axis. Each of the rungs has a sectional shape with thickness or a radial extension comparable to or greater than its width or its azimuthal extension. Measures of the width and thickness of the rungs may be determined by using them as parameters to calculate the values of Q factor from an analytical procedure to locate parameter value ranges corresponding to maximal Q. Geometric calculations for filling factor yield ranges of parameters providing for compromise parameter values. Saddle coils have been found to exhibit similar enhancement of Q with radially oriented conductor cross section.
    Type: Application
    Filed: April 12, 2002
    Publication date: October 16, 2003
    Inventors: Thomas de Swiet, Wai Ha Wong, Marco Romo, James Finnigan, Sean Burns
  • Patent number: 6593743
    Abstract: A radio-frequency (RF) coil for a nuclear magnetic resonance (NMR) probe includes rounded longitudinal conductors connecting end rings formed by sheets. The rounded conductors can be formed by curled sheets or wires. The rounded conductors allow reduced RF losses at the coil window edges, and thus allow increased coil sensitivities. The rounded conductors also allow increased coil sensitivities for an orthogonal coil, by allowing increased transparency to the magnetic field generated by the orthogonal coil. A curled-sheet RF coil can be generated from a single etched sheet by curling longitudinal sections of the sheet into tubular longitudinal conductors. To make such a coil, each longitudinal section is inserted into a longitudinal slot of a sheet-curling member, and the member is rotated about its longitudinal axis. As the curling member is rotated, the longitudinal sheet section wraps around the curling member and becomes curled.
    Type: Grant
    Filed: October 26, 2001
    Date of Patent: July 15, 2003
    Assignee: Varian, Inc.
    Inventors: Thomas de Swiet, Marco A. Romo, Nancy Winward
  • Publication number: 20030080740
    Abstract: A radio-frequency (RF) coil for a nuclear magnetic resonance (NMR) probe includes rounded longitudinal conductors connecting end rings formed by sheets. The rounded conductors can be formed by curled sheets or wires. The rounded conductors allow reduced RF losses at the coil window edges, and thus allow increased coil sensitivities. The rounded conductors also allow increased coil sensitivities for an orthogonal coil, by allowing increased transparency to the magnetic field generated by the orthogonal coil. A curled-sheet RF coil can be generated from a single etched sheet by curling longitudinal sections of the sheet into tubular longitudinal conductors. To make such a coil, each longitudinal section is inserted into a longitudinal slot of a sheet-curling member, and the member is rotated about its longitudinal axis. As the curling member is rotated, the longitudinal sheet section wraps around the curling member and becomes curled.
    Type: Application
    Filed: October 26, 2001
    Publication date: May 1, 2003
    Inventors: Thomas de Swiet, Marco A. Romo, Nancy Winward