Patents by Inventor David Harris Stewart

David Harris Stewart 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: 20170183920
    Abstract: A method for manufacturing a centralizer. The method includes selecting a tubular having a first inner diameter, cutting the tubular to form a blank including at least one end collar and ribs integrally-formed therewith, and swaging the at least one end collar such that the first inner diameter is modified to a second inner diameter.
    Type: Application
    Filed: May 6, 2015
    Publication date: June 29, 2017
    Inventors: George W. Ribble, Michael L. Betik, David Harris Stewart, Eugene Edward Miller
  • Patent number: 7897248
    Abstract: A method of forming a composite of embedded nanofibers in a polymer matrix is disclosed. The method includes incorporating nanofibers in a plastic matrix forming agglomerates, and uniformly distributing the nanofibers by exposing the agglomerates to hydrodynamic stresses. The hydrodynamic said stresses force the agglomerates to break apart. In combination or additionally elongational flow is used to achieve small diameters and alignment. A nanofiber reinforced polymer composite system is disclosed. The system includes a plurality of nanofibers that are embedded in polymer matrices in micron size fibers. A method for producing nanotube continuous fibers is disclosed. Nanofibers are fibrils with diameters of 100 nm, multiwall nanotubes, single wall nanotubes and their various functionalized and derivatized forms. The method includes mixing a nanofiber in a polymer; and inducing an orientation of the nanofibers that enables the nanofibers to be used to enhance mechanical, thermal and electrical properties.
    Type: Grant
    Filed: February 4, 2008
    Date of Patent: March 1, 2011
    Assignee: William Marsh Rice University
    Inventors: Enrique V. Barrera, Fernando J. Rodriguez-Macias, Karen Lozano, Luis Paulo Felipe Chibante, David Harris Stewart
  • Publication number: 20090104386
    Abstract: A method of forming a composite of embedded nanofibers in a polymer matrix is disclosed. The method includes incorporating nanofibers in a plastic matrix forming agglomerates, and uniformly distributing the nanofibers by exposing the agglomerates to hydrodynamic stresses. The hydrodynamic said stresses force the agglomerates to break apart. In combination or additionally elongational flow is used to achieve small diameters and alignment. A nanofiber reinforced polymer composite system is disclosed. The system includes a plurality of nanofibers that are embedded in polymer matrices in micron size fibers. A method for producing nanotube continuous fibers is disclosed. Nanofibers are fibrils with diameters 100 nm, multiwall nanotubes, single wall nanotubes and their various functionalized and derivatized forms. The method includes mixing a nanofiber in a polymer; and inducing an orientation of the nanofibers that enables the nanofibers to be used to enhance mechanical, thermal and electrical properties.
    Type: Application
    Filed: February 4, 2008
    Publication date: April 23, 2009
    Inventors: Enrique V. Barrera, Fernando J. Rodriguez-Macias, Karen Lozano, Luis Paulo Felipe Chibante, David Harris Stewart