Patents Represented by Attorney Harry T. Stephenson

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  • Corrosion inhibitor
    Patent number: 6811747
    Abstract: The present invention relates to water treatment chemical formulations, and more particularly to chemical formulations used to treat water containing halogens as a sanitizing agent. The water treatment chemical formulations contain cyanuric acid and an alkali metal molybdate or silicate as an anticorrosion agent.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: November 2, 2004
    Assignee: Bioquest, LLC
    Inventor: Michael A. Silveri
  • Method and device for the determination of polymeric biguanides in aqueous fluids
    Patent number: 5498547
    Abstract: A test method and device is described for determining biguanides in aqueous fluids such as swimming pool water which involve contacting the fluid with a matrix incorporating a pH sensitive indicator material which exhibits the biguanide error effect. A buffer is advantageously used to maintain the test system within a defined constant pH range to eliminate the effect of pH changes on the test system.
    Type: Grant
    Filed: May 24, 1994
    Date of Patent: March 12, 1996
    Assignee: Environmental Test Systems, Inc.
    Inventors: Kenneth A. Blake, Chauncey O. Rupe, Carol A. Terry
  • Multilayer test device having fusion bonding attachment layer
    Patent number: 5330715
    Abstract: A unitized multilayer dry reagent analytical chemistry test structure and device and method of fabricating such device is described. The device includes two or more contiguous layers of absorbent or porous paper or polymeric material, at least one of which is incorporated with a test reagent composition, the layers attached to each other with intermediate porous attachment layers by fusion bonding. When the device is contacted with the fluid being tested the attachment layers allow the free flow of such fluid from one layer to the next.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: July 19, 1994
    Assignee: Environmental Test Systems, Inc.
    Inventors: Kenneth A. Blake, James E. Christner, Leonard J. Lucchese, II
  • Test for Helicobacter pylori
    Patent number: 5314804
    Abstract: A rapid method and easy to use unitized test device is disclosed for determining the presence of Helicobacter pylori in a biological tissue specimen by detecting the presence of urease in the tissue. The system basically utilizes a multilayer test device for separating and optimizing the various reactions involved, i.e. the urease in the specimen with a substrate and the ammonia generated thereby with an indicator element.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: May 24, 1994
    Assignee: Serim Research Corporation
    Inventors: Robert C. Boguslaski, Robert J. Carrico
  • Test devices and methods for determining halides in aqueous samples
    Patent number: 5229299
    Abstract: A test device and method of use for determination of aqueous halide ions is described. The device has a porous matrix containing a silver dichromate reagent that gives a colorimetric response in the presence of halide ions and a cationic substance that prevents the formation of silver oxide products. The cationic substance has no colorimetric response in the presence of halide ions that would interfere with the measurement of the colorimetric change of the silver dichromate reagent.
    Type: Grant
    Filed: April 21, 1992
    Date of Patent: July 20, 1993
    Assignee: Environmental Test Systems, Inc.
    Inventor: Carol Ann Terry
  • Test composition and device for the determination of cyanuric acid in water
    Patent number: 4855239
    Abstract: A colorimetric test reagent composition is presented for determining the amount of cyanuric acid in water. Cyanuric acid is added to outdoor swimming pool water to stabilize the chlorine added as a sanitizer. Basically the test composition utilizes melamine and an indicator material which responds to a change in pH of the test environment caused by the action of cynanuric acid on the reagent composition. Preferably the test composition is incorporated in a porous matrix which results in a convenient solid state test device.
    Type: Grant
    Filed: December 28, 1987
    Date of Patent: August 8, 1989
    Assignee: Environmental Test Systems, Inc.
    Inventor: Chauncey O. Rupe