Patents by Inventor Randall L. Simpson

Randall L. Simpson 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: 20040060625
    Abstract: Sol-gel chemistry is used to prepare igniters comprising energetic multilayer structures coated with energetic booster materials. These igniters can be tailored to be stable to environmental aging, i.e., where the igniters are exposed to extremes of both hot and cold temperatures (−30 C to 150C) and both low (0%) and high relative humidity (100%).
    Type: Application
    Filed: October 1, 2002
    Publication date: April 1, 2004
    Applicant: The Regents of the University of California.
    Inventors: Troy W. Barbee, Randall L. Simpson, Alexander E. Gash, Joe H. Satcher
  • Patent number: 6666935
    Abstract: Sol-gel chemistry is used for the preparation of energetic materials (explosives, propellants and pyrotechnics) with improved homogeneity, and/or which can be cast to near-net shape, and/or made into precision molding powders. The sol-gel method is a synthetic chemical process where reactive monomers are mixed into a solution, polymerization occurs leading to a highly cross-linked three dimensional solid network resulting in a gel. The energetic materials can be incorporated during the formation of the solution or during the gel stage of the process. The composition, pore, and primary particle sizes, gel time, surface areas, and density may be tailored and controlled by the solution chemistry. The gel is then dried using supercritical extraction to produce a highly porous low density aerogel or by controlled slow evaporation to produce a xerogel. Applying stress during the extraction phase can result in high density materials.
    Type: Grant
    Filed: September 9, 1997
    Date of Patent: December 23, 2003
    Assignee: The Regents of the University of California
    Inventors: Randall L. Simpson, Ronald S. Lee, Thomas M. Tillotson, Lawrence W. Hrubesh, Rosalind W. Swansiger, Glenn A. Fox
  • Publication number: 20020104599
    Abstract: A synthetic route for producing nanostructure metal-oxide-based materials using sol-gel processing. This procedure employs the use of stable and inexpensive hydrated-metal inorganic salts and environmentally friendly solvents such as water and ethanol. The synthesis involves the dissolution of the metal salt in a solvent followed by the addition of a proton scavenger, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively. Using this method synthesis of metal-oxide nanostructured materials have been carried out using inorganic salts, such as of Fe3+, Cr3+, Al3+, Ga3+, In3+, Hf4+, Sn4+, Zr4+, Nb5+, W6+, Pr3+, Er3+, Nd3+, Ce3+, U3+ and Y3+.
    Type: Application
    Filed: October 16, 2001
    Publication date: August 8, 2002
    Inventors: Thomas M. Tillotson, Randall L. Simpson, Lawrence W. Hrubesh, Alexander Gash
  • Patent number: 5648636
    Abstract: A simulator which is chemically equivalent to an explosive, but is not detonable or explodable. The simulator is a combination of an explosive material with an inert material, either in a matrix or as a coating, where the explosive has a high surface ratio but small volume ratio. The simulator has particular use in the training of explosives detecting dogs, calibrating analytical instruments which are sensitive to either vapor or elemental composition, or other applications where the hazards associated with explosives is undesirable but where chemical and/or elemental equivalence is required. The explosive simulants may be fabricated by different techniques. A first method involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and a second method involves coating inert substrates with thin layers of explosive.
    Type: Grant
    Filed: May 9, 1995
    Date of Patent: July 15, 1997
    Assignee: Regents of the University of California
    Inventors: Randall L. Simpson, Cesar O. Pruneda
  • Patent number: 5413812
    Abstract: A simulator which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules.
    Type: Grant
    Filed: April 1, 1994
    Date of Patent: May 9, 1995
    Assignee: The Regents of the University of California
    Inventors: Randall L. Simpson, Cesar O. Pruneda
  • Patent number: 5359936
    Abstract: A simulator which is chemically equivalent to an explosive, but is not detonable. The simulator has particular use in the training of explosives detecting dogs and calibrating sensitive analytical instruments. The explosive simulants may be fabricated by different techniques, a first involves the use of standard slurry coatings to produce a material with a very high binder to explosive ratio without masking the explosive vapor, and the second involves coating inert beads with thin layers of explosive molecules.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: November 1, 1994
    Assignee: Regents of the University of California
    Inventors: Randall L. Simpson, Cesar O. Pruneda