Patents by Inventor Grazyna Zakrzewska-Trznadel

Grazyna Zakrzewska-Trznadel 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).

  • Enrichment of water in components of heavy water
    Patent number: 5084181
    Abstract: A method for the enrichment of the natural water in the components of heavy water such as D.sub.2 O and/or HDO being the source of deuterium. The method utilizes the passing of water through semipermeable hydrophobic membranes on which phase transition occurs. The latter is caused by vacuum or neutral carrier gas on the vapor side of the membrane. Lighter isotopes preferentially pass through the membrane leaving the original water enriched in heavy water components.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: January 28, 1992
    Assignee: The University of Tennessee Research Corporation
    Inventors: W. Alexander Van Hook, Andrzej G. Chmielewski, Grazyna Zakrzewska-Trznadel, Nada Miljevic
  • Method of enrichment of oxygen-18 in natural water
    Patent number: 5057225
    Abstract: A method for the enrichment of natural water in oxygen-18. Permeation followed by phase transition of lighter isotopes of water across a hydrophobic semipermeable membrane are employed to enrich the natural water in O-18 isotopes. Unexpectedly large fractionation factors have been found.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: October 15, 1991
    Assignee: The University of Tennessee Research Corporation
    Inventors: W. Alexander van Hook, Andrzej G. Chmielewski, Grazyna Zakrzewska-Trznadel, Nada Miljevic