Patents by Inventor Dennis S. Tucker

Dennis S. Tucker 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).

  • Publication number: 20240131590
    Abstract: A method of forming an article comprises forming a feed material around one or more shapeholders and sintering the feed material and the one or more shapeholders to form a sintered article comprising the one or more shapeholders in a base material. The sintered article is exposed to a solvent to remove the one or more shapeholders from the base material. Additional methods are disclosed, as well as articles including one or more microchannels exhibiting a diameter of from about 5 ?m to about 10 mm.
    Type: Application
    Filed: October 12, 2023
    Publication date: April 25, 2024
    Inventors: Donna P. Guillen, Robert V. Fox, Dennis S. Tucker, Troy B. Holland
  • Patent number: 11230501
    Abstract: Nano-sized particles of barium-titanate are heated as a gas mixture of 25% hydrogen and 75% nitrogen is passed there through yielding particles of barium-titanate having oxygen vacancies therein. The particles of barium-titanate having oxygen vacancies therein are coated with silica yielding silica-coated particles having a silica coating thickness in a range of 2-5 nanometers. The silica-coated particles are sintered by application of pressure in a range of 35-50 megapascals and temperature in a range of 950-1050° C. The sintered quantity of material is cooled at a cooling rate in a range of 1-3° C. per minute at least until the temperature thereof is less than 120° C.
    Type: Grant
    Filed: February 1, 2021
    Date of Patent: January 25, 2022
    Assignee: United States of America as represented by the Administrator of NASA
    Inventors: Dennis S. Tucker, Terry D. Rolin, Curtis W. Hill
  • Patent number: 10442721
    Abstract: In a unit gravity environment, a glass preform is encased in a material to generate an encased glass preform. The material remains solid at the glass preform's crystal melting temperature and is inert with respect to the glass preform. The encased glass preform is placed in a microgravity environment and heated to a temperature above the crystal melting temperature until the glass preform melts and is free of crystals, wherein a crystallite-free glass preform is encased within the material. The crystallite-free glass preform is then cooled in the microgravity environment to generate a solid crystallite-free glass preform encased within the material. While still in the microgravity environment, the material encasing the solid crystallite-free glass preform is removed in the microgravity environment and the solid crystallite-free glass preform is polished. A glass optical fiber is then drawn from the solid crystallite-free glass preform in the microgravity environment.
    Type: Grant
    Filed: April 15, 2019
    Date of Patent: October 15, 2019
    Inventors: Dennis S. Tucker, Jeremy A. Tucker
  • Patent number: 7848606
    Abstract: A method is provided for eliminating crystals in non-oxide optical fiber preforms as well as optical fibers drawn therefrom. The optical-fiber-drawing axis of the preform is aligned with the force of gravity. A magnetic field is applied to the preform as it is heated to at least a melting temperature thereof. The magnetic field is applied in a direction that is parallel to the preform's optical-fiber-drawing axis. The preform is then cooled to a temperature that is less than a glass transition temperature of the preform while the preform is maintained in the magnetic field. When the processed preform is to have an optical fiber drawn therefrom, the preform's optical-fiber-drawing axis is again aligned with the force of gravity and a magnetic field is again applied along the axis as the optical fiber is drawn from the preform.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: December 7, 2010
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Michael R. LaPointe, Dennis S. Tucker
  • Patent number: 7807097
    Abstract: A process for producing foamed aluminum in space comprising the steps of: heating aluminum until it is molten; applying the force of gravity to the molten aluminum; injecting gas into the molten aluminum to produce molten foamed aluminum; and allowing the molten foamed aluminum to cool to below melting temperature. The apparatus for carrying out this invention comprises: a furnace which rotates to simulate the force of gravity and heats the aluminum until it is molten; a door on the furnace, which is opened for charging the aluminum into the furnace, closed for processing and opened again for removal of the foamed aluminum; a gas injection apparatus for injecting gas into the molten aluminum within the furnace; and an extraction apparatus adjacent the door for removing the foamed aluminum from the furnace.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: October 5, 2010
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Dennis S. Tucker
  • Patent number: 7594530
    Abstract: This invention is a process for producing foamed material in space comprising the steps of: rotating the material to simulate the force of gravity; heating the rotating material until it is molten; extruding the rotating, molten material; injecting gas into the extruded, rotating, molten material to produce molten foamed material; allowing the molten foamed material to cool to below melting temperature to produce the foamed material. The surface of the extruded foam may be heated to above melting temperature and allowed to cool to below melting temperature. The extruded foam may also be cut to predetermined length. The starting material may be metal or glass. Heating may be accomplished by electrical heating elements or by solar heating.
    Type: Grant
    Filed: November 19, 2007
    Date of Patent: September 29, 2009
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Dennis S. Tucker