James E Atwater

US Patent:

58829377, Mar 16, 1999

Filed:

Jul 9, 1997

Appl. No.:

8/903279

Inventors:

Richard L. Sauer - League City TX
James R. Akse - Roseburg OR
John O. Thompson - Roseburg OR
James E. Atwater - Eugene OR

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

G01N 3300
G01N 2700

US Classification:

436113

Abstract:

Ammonia monitor and method of use are disclosed. A continuous, real-time determination of the concentration of ammonia in an aqueous process stream is possible over a wide dynamic range of concentrations. No reagents are required because pH is controlled by an in-line solid-phase base. Ammonia is selectively transported across a membrane from the process stream to an analytical stream under pH control. The specific electrical conductance of the analytical stream is measured and used to determine the concentration of ammonia.

US Patent:

57926212, Aug 11, 1998

Filed:

Jun 28, 1995

Appl. No.:

8/496230

Inventors:

Charles E. Verostko - Houston TX
James E. Atwater - Eugene OR
James R. Akse - Roseburg OR
Jeffrey L. DeHart - Myrtle Creek OR
Richard R. Wheeler - Myrtle Creek OR

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

C12Q 154
C12Q 128
C12Q 126
G01N 2176

US Classification:

435 14

Abstract:

A "reagentless" chemiluminescent biosensor and method for the determination of hydrogen peroxide, ethanol and D-glucose in water. An aqueous stream is basified by passing it through a solid phase base bed. Luminol is then dissolved in the basified effluent at a controlled rate. Oxidation of the luminol is catalyzed by the target chemical to produce emitted light. The intensity of the emitted light is detected as a measure of the target chemical concentration in the aqueous stream. The emitted light can be transmitted by a fiber optic bundle to a remote location from the aqueous stream for a remote reading of the target chemical concentration.

US Patent:

59104481, Jun 8, 1999

Filed:

Apr 4, 1997

Appl. No.:

8/826645

Inventors:

James E. Atwater - Eugene OR
James R. Akse - Roseburg OR
Jeffrey DeHart - Yoncalla OR

Assignee:

Umpqua Research Company - Myrtle Creek OR

International Classification:

G01N 3318

US Classification:

436133

Abstract:

The process of this invention comprises providing a membrane for separating CO. sub. 2 into a first CO. sub. 2 sample phase and a second CO. sub. 2 analyte phase. CO. sub. 2 is then transported through the membrane thereby separating the CO. sub. 2 with the membrane into a first CO. sub. 2 sample phase and a second CO. sub. 2 analyte liquid phase including an ionized, conductive, dissociated CO. sub. 2 species. Next, the concentration of the ionized, conductive, dissociated CO. sub. 2 species in the second CO. sub. 2 analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO. sub. 2 to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO. sub. 2 in the first CO. sub. 2 sample phase.

US Patent:

56437994, Jul 1, 1997

Filed:

Oct 31, 1994

Appl. No.:

8/332570

Inventors:

James E. Atwater - Eugene OR
James R. Akse - Roseburg OR
Jeffrey DeHart - Yoncalla OR

Assignee:

Umpqua Research Company - Myrtle Creek OR

International Classification:

G07N 3318

US Classification:

436133

Abstract:

The process of this invention comprises providing a membrane for separating CO. sub. 2 into a first CO. sub. 2 sample phase and a second CO. sub. 2 analyte phase. CO. sub. 2 is then transported through the membrane thereby separating the CO. sub. 2 with the membrane into a first CO. sub. 2 sample phase and a second CO. sub. 2 analyte liquid phase including an ionized, conductive, dissociated CO. sub. 2 species. Next, the concentration of the ionized, conductive, dissociated CO. sub. 2 species in the second CO. sub. 2 analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO. sub. 2 to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO. sub. 2 in the first CO. sub. 2 sample phase.

US Patent:

60774789, Jun 20, 2000

Filed:

Jun 30, 1998

Appl. No.:

9/111371

Inventors:

Richard L. Sauer - League City TX
James E. Atwater - Eugene OR
Roger W. Dahl - Tenmile OR
Frank C. Garmon - Canyonville OR
Teddie D. Lunsford - Sutherlin OR
William F. Michalek - Roseburg OR
Richard R. Wheeler - Azalea OR

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

A61L 208

US Classification:

422 21

Abstract:

A device and method for elimination of contamination during transfer of materials either into or from bioreactors, food containers, or other microbially vulnerable systems. Using microwave power, thermal sterilizations of mating fixtures are achieved simply, reliably, and quickly by the volatilization of small quantities of water to produce superheated steam which contacts all exposed surfaces.