Patents by Inventor Ramanathan Panayappan

Ramanathan Panayappan 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: 5364574
    Abstract: A composition is disclosed for forming an EMI shielding gasket for instalion against a metal object, such as an aluminum frame member of an aircraft, wherein the composition is comprised of a mixture of a prepolymer composition of a flexible polyurethane material, a sacrificial metallic material which provides electrical conductivity and anodic protection against corrosion of the metal object, and a curing agent for curing the prepolymer composition. The sacrificial metallic material can be a metal salt selected from the group consisting of water soluble zinc and cadmium salts. Water can also be present to serve two functions, as a curing agent for the polyurethane and as a foaming agent, producing carbon dioxide. A method is also providing for installing an EMI shielding gasket on an aircraft between a graphite skin panel and a metal frame member. The composition for forming the EMI shielding gasket on a metal surface can also include an agent that cleans the metal surface to which the gasket is applied.
    Type: Grant
    Filed: April 2, 1992
    Date of Patent: November 15, 1994
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Ramanathan Panayappan, John C. Cooper, deceased
  • Patent number: 4900715
    Abstract: Superconducting compositions of the general formula A.sub.n Q.sub.m Cu.sub.3 O.sub.y are prepared by wet mixing a combination organic acid salts, inorganic acid salts and oxides of A, Q and Cu, wherein at least one salt is an organic acid salt, drying the mixed salts, and then heating the resultant mixed salts to a temperature between 500.degree. and 950.degree. C. The temperature is maintained for a time sufficient to form a substantially orthorhombic superconducting composition. The method achieves good results with only one heating step. The presence of at least one organic salt causes carbonate and nitrate salts of A, Q and Cu to convert to oxides at temperatures between 300.degree. and 400.degree. C. With lower processing temperatures, semiconductor materials and superconducting materials can be processed together.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: February 13, 1990
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: John C. Cooper, Ramanathan Panayappan, Joseph T. Guy
  • Patent number: 4591510
    Abstract: A chemical composition formed from a chelating agent, polymeryable bonding agent, and a high dielectric solvent which eliminates intermodulation interference when applied to "rusty bolt" junctions.
    Type: Grant
    Filed: April 12, 1985
    Date of Patent: May 27, 1986
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Ramanathan Panayappan, John C. Cooper
  • Patent number: 4529450
    Abstract: A metal oxide composition containing a water soluble polymer, erythorbic acid, a surfactant, a buffer, ascorbic acid (optional), and citric acid (optional). The novel composition may be used according to at least two novel methods. The composition may be sprinkled as a powder onto a wetted, oxidized surface, and then rinsed off, or it may be dissolved in water and the metal surface exposed to the resulting solution.
    Type: Grant
    Filed: October 18, 1983
    Date of Patent: July 16, 1985
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Ramanathan Panayappan
  • Patent number: 4325744
    Abstract: A method of cleaning metal surfaces, particularly irregularly shaped metal surfaces such as exist on a ship, wherein a thick aqueous solution of a water soluble polymer, preferably polyvinylpyrrolidone (PVP), and a chelating agent, is applied to a rusty metal surface as a thick paste, which gradually hardens into an encapsulating film during cleaning. After cleaning is complete, the film and the corrosion products are easily peeled from the clean surface and can be disposed of as solid waste.
    Type: Grant
    Filed: July 25, 1980
    Date of Patent: April 20, 1982
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Ramanathan Panayappan, David L. Venezky
  • Patent number: H348
    Abstract: A chemical composition suitable for reducing intermodulation interference, and which also possesses improved penetrating qualities, contains the following:______________________________________ % by weight ______________________________________ Polyvinylpyrrolidinone (PVP-K-90) 10 Citric Acid 10 Tetrasodium salt of EDTA 5 Sodium Bicarbonate 5 Erythorbic Acid 50 Sodium Tetraborate Decahydrate 7.5 Sodium Laurylsulfate 2.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: October 6, 1987
    Inventor: Ramanathan Panayappan