Patents by Inventor Arthur J. Stipanovic

Arthur J. Stipanovic 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: 5736491
    Abstract: A method of improving the fuel economy characteristic of a lubricant by friction reduction including mixing the lubricant with a C.sub.2 to C.sub.12 aliphatic carboxylate salt of molybdenum and a zinc dialkyldithiophosphate or zinc dialkyldithiocarbamate is disclosed. The synergistic interaction of the aliphatic carboxylate salt of molybdenum and the zinc salt results in at least a 30% reduction in the coefficient of friction at 100.degree. C.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: April 7, 1998
    Assignee: Texaco Inc.
    Inventors: Jitendra A. Patel, Arthur J. Stipanovic, Jeffrey P. Schoonmaker
  • Patent number: 5236046
    Abstract: A variant strain of Agrobacter radiobacter has been found to produce a unique heteropolysaccharide containing D-galactose, D-glucose and pyruvic acid in approximate molar ratios of 2:15:2 in a seventeen member repeat unit having the structure shown below, wherein Glc represents D-glucose, Gal represents D-galactose and Pyr represents pyruvic acid, with the numerals indicating the positions of linkage in these ring structures. The heteropolysaccharide is useful in mobility control in oil reservoir formations, especially when crosslinked with trivalent metal cations (Cr.sup.3+, Al.sup.3+, Fe.sup.3+ or Ti.sup.3+) to form a gel which preferentially fills high permeability zones in such reservoirs.
    Type: Grant
    Filed: January 18, 1991
    Date of Patent: August 17, 1993
    Assignee: Texaco Inc.
    Inventors: Peter D. Robison, Arthur J. Stipanovic, Charles E. Stypulkoski, Nick C. Wan, Susan Easter
  • Patent number: 4874044
    Abstract: A process for recovering hydrocarbons from a subterranean hydrocarbon bearing formation penetrated by an injection well and a production well which comprises injecting an aqueous drive fluid into the formation and forcing the drive fluid through the formation to recover the hydrocarbons from the production well.
    Type: Grant
    Filed: October 11, 1988
    Date of Patent: October 17, 1989
    Assignee: Texaco Inc.
    Inventors: Peter D. Robison, Arthur J. Stipanovic
  • Patent number: 4548268
    Abstract: A process for recovering hydrocarbons from a subterranean hydrocarbon bearing formation penetrated by injection well and a production well includes the steps of injecting into the formation via an injection well an aqueous drive fluid comprising water and more than about 200 parts per million of Beta-(1.fwdarw.6)-D-glucan having an average molecular weight of more than about 2.times.10.sup.4 and comprising recurring units of the disaccharide gentiobiose: ##STR1## forcing said aqueous drive fluid through the formation and recovering hydrocarbons from the production well. The process also includes using a more concentrated solution of the glucan, more than about 2,000 parts per million, as a vertical conformance agent. The invention also includes a concentrate of the glucan in dimethylsulfoxide or in a 4 molar or higher concentration of aqueous urea which is diluted to form the aqueous drive fluid.
    Type: Grant
    Filed: December 27, 1983
    Date of Patent: October 22, 1985
    Assignee: Texaco, Inc.
    Inventor: Arthur J. Stipanovic