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: 7560922Abstract: 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: GrantFiled: September 29, 2008Date of Patent: July 14, 2009Assignee: Varian, Inc.Inventors: Thomas M. Barbara, Thomas de Swiet
-
Publication number: 20090021259Abstract: 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: ApplicationFiled: September 29, 2008Publication date: January 22, 2009Inventors: Thomas M. Barbara, Thomas de Swiet
-
Patent number: 7476330Abstract: 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: GrantFiled: September 24, 2003Date of Patent: January 13, 2009Assignee: Varian, Inc.Inventors: Thomas M. Barbara, Thomas de Swiet
-
Patent number: 7068034Abstract: 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: GrantFiled: October 19, 2004Date of Patent: June 27, 2006Assignee: Varian, Inc.Inventor: Thomas de Swiet
-
Patent number: 6917201Abstract: 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: GrantFiled: December 9, 2002Date of Patent: July 12, 2005Assignee: Varian, Inc.Inventor: Thomas de Swiet
-
Publication number: 20050077900Abstract: 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: ApplicationFiled: October 19, 2004Publication date: April 14, 2005Inventor: Thomas de Swiet
-
Patent number: 6812703Abstract: 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: GrantFiled: December 17, 2002Date of Patent: November 2, 2004Assignee: Varian, Inc.Inventors: Thomas de Swiet, Knut G. Mehr
-
Publication number: 20040113617Abstract: 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: ApplicationFiled: December 17, 2002Publication date: June 17, 2004Inventors: Thomas de Swiet, Knut G. Mehr
-
Publication number: 20040108852Abstract: 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: ApplicationFiled: December 9, 2002Publication date: June 10, 2004Inventor: Thomas de Swiet
-
Patent number: 6667674Abstract: 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: GrantFiled: April 12, 2002Date of Patent: December 23, 2003Assignee: Varian, Inc.Inventors: Thomas de Swiet, Wai Ha Wong, Marco Romo, James Finnigan, Sean Burns
-
Publication number: 20030193380Abstract: 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: ApplicationFiled: April 12, 2002Publication date: October 16, 2003Inventors: Thomas de Swiet, Wai Ha Wong, Marco Romo, James Finnigan, Sean Burns
-
Patent number: 6593743Abstract: 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: GrantFiled: October 26, 2001Date of Patent: July 15, 2003Assignee: Varian, Inc.Inventors: Thomas de Swiet, Marco A. Romo, Nancy Winward
-
Publication number: 20030080740Abstract: 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: ApplicationFiled: October 26, 2001Publication date: May 1, 2003Inventors: Thomas de Swiet, Marco A. Romo, Nancy Winward