Patents by Inventor Gregory Walker

Gregory Walker 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: 6911546
    Abstract: A method is provided for carrying out depolymerization of a polymer containing electrophilic linkages in the presence of a catalyst and a nucleophilic reagent, wherein production of undesirable byproducts resulting from polymer degradation is minimized. The reaction can be carried out at a temperature of 80° C. or less, and generally involves the use of an organic, nonmetallic catalyst, thereby ensuring that the depolymerization product(s) are substantially free of metal contaminants. In an exemplary depolymerization method, the catalyst is a carbene compound such as an N-heterocyclic carbene, or is a precursor to a carbene compound. The method provides an important alternative to current recycling techniques such as those used in the degradation of polyesters, polyamides, and the like.
    Type: Grant
    Filed: December 26, 2002
    Date of Patent: June 28, 2005
    Assignee: International Business Machines Corporation
    Inventors: James Lupton Hedrick, Pinar Kilickiran, Gregory Walker Nyce, Robert M. Waymouth
  • Publication number: 20050103634
    Abstract: Flow-through capacitors are provided with one or more charge barrier layers. Ions trapped in the pore volume of flow-through capacitors cause inefficiencies as these ions are expelled during the charge cycle into the purification path. A charge barrier layer holds these pore volume ions to one side of a desired flow stream, thereby increasing the efficiency with which the flow-through capacitor purifies or concentrates ions.
    Type: Application
    Filed: December 7, 2004
    Publication date: May 19, 2005
    Inventors: Marc Andelman, Gregory Walker
  • Publication number: 20050027156
    Abstract: An ocular brachytherapy device, generally comprising a catheter and wire, impregnated with radioactive material, are provided. The wire is formed having a desired treatment shape and size such that it can be placed near an area requiring treatment and effectuate treatment while not affecting adjacent areas. For ease in placement near such areas the wire is preferably formed using materials having properties that permit formation into a desired shape while allowing the wire to be straightened for retraction into the catheter, the shape returning upon removal from the catheter. The wire is preferably impregnated with radioactive material. When the catheter is placed near the area of treatment and the wire is pushed out of the catheter, the wire retakes the desired form and provides a therapeutic radioactive treatment to the area.
    Type: Application
    Filed: April 30, 2004
    Publication date: February 3, 2005
    Inventors: Jose Pulido, Russell Hamilton, Gregory Walker
  • Publication number: 20040127720
    Abstract: A method is provided for carrying out depolymerization of a polymer containing electrophilic linkages in the presence of a catalyst and a nucleophilic reagent, wherein production of undesirable byproducts resulting from polymer degradation is minimized. The reaction can be carried out at a temperature of 80° C. or less, and generally involves the use of an organic, nonmetallic catalyst, thereby ensuring that the depolymerization product(s) are substantially free of metal contaminants. In an exemplary depolymerization method, the catalyst is a carbene compound such as an N-heterocyclic carbene, or is a precursor to a carbene compound. The method provides an important alternative to current recycling techniques such as those used in the degradation of polyesters, polyamides, and the like.
    Type: Application
    Filed: December 26, 2002
    Publication date: July 1, 2004
    Inventors: James Lupton Hedrick, Pinar Kilickiran, Gregory Walker Nyce, Robert M. Waymouth
  • Publication number: 20040127744
    Abstract: A method is provided for carrying out depolymerization of a polymer containing electrophilic linkages in the presence of a catalyst and a nucleophilic reagent, wherein production of undesirable byproducts resulting from polymer degradation is minimized. The reaction can be carried out at a temperature of 80° C. or less, and generally involves the use of an organic, nonmetallic catalyst, thereby ensuring that the depolymerization product(s) are substantially free of metal contaminants. In an exemplary depolymerization method, the catalyst is a carbene compound such as an N-heterocyclic carbene, or is a precursor to a carbene compound. The method provides an important alternative to current recycling techniques such as those used in the degradation of polyesters, polyamides, and the like.
    Type: Application
    Filed: January 30, 2003
    Publication date: July 1, 2004
    Inventors: James Lupton Hedrick, Pinar Kilickiran, Gregory Walker Nyce, Robert M. Waymouth