David E Walters

US Patent:

6514316, Feb 4, 2003

Filed:

Aug 22, 2001

Appl. No.:

09/938140

Inventors:

Gregory Scott Gaisford - Denver CO
David L. Walters - Fort Collins CO

Assignee:

MT Systems, LLC - Denver CO

International Classification:

B01D 1508

US Classification:

95 87, 96101, 96102

Abstract:

Capillary column oxidation in gas chromatography systems, particularly of polyimide clad columns, is a major cause of column failure and it limits the maximum temperature at which columns can be used. A gas chromatography column oven system is described which utilizes inert gas to substantially eliminate column oxidation thereby increasing column thermal stability. These column oven systems thus increase column lifetime and maximum operating temperature. The column oven systems comprise pneumatically sealed oven enclosures with sealed access ports, sealed sample line ports, and inlet and outlet gas ports to which are connected an inert gas supply and an exhaust gas control system respectively.

US Patent:

7467324, Dec 16, 2008

Filed:

Dec 6, 2004

Appl. No.:

11/006015

Inventors:

Bhavesh P. Davda - Westminster CO, US
John F. Kelly - Lafayette CO, US
David L. Walters - Louisville CO, US

Assignee:

Ayaya Inc. - Basking Ridge NJ

International Classification:

G06F 11/00

US Classification:

714 6, 714 5, 714 8, 711162

Abstract:

A system and method for continuing to provide processing in a processing system is disclosed. In one embodiment, a processing system is provided comprising a secondary storage device, a memory, a processor, an operating system, and a plurality of processes stored in the secondary data storage device. The plurality of processes comprise a first group of processes and a second group of processes. The first group of processes is adapted to be swapped between the secondary data storage device and the memory for execution. The second group of processes is adapted to be locked into the memory of the processing system during operation. The request to lock and unlock a process is affected by a watchdog process unrelated to the process being locked. Configuration information for the watchdog process identifies the processes in the first and/or second groups.

US Patent:

60939214, Jul 25, 2000

Filed:

Mar 4, 1999

Appl. No.:

9/262230

Inventors:

Scott Gaisford - Denver CO
David L. Walters - Westminster CO

Assignee:

MT Systems, LLC - Denver CO

International Classification:

H05B 680
H05B 672
G01N 3002

US Classification:

219748

Abstract:

A microwave heating apparatus is used for heating a chromatographic column assembly containing a microwave absorbing material. The microwave heating apparatus includes an antenna transmitting a microwave signal and a resonant cavity containing the chromatographic column assembly and the antenna. The chromatographic column assembly extends relative to predetermined electromagnetic field strength contours within the resonant cavity to provide a predetermined heating profile along the length of the chromatographic column assembly. For example, a single-mode chromatographic column microwave oven can be used to heat a coiled chromatography column to a desired temperature gradient along its length. Oven design embodiments utilizing coaxial transmission line structures, coaxial resonators, and cylindrical resonators are described. To control the electromagnetic field gradient in the axial direction, the oven designs provide for varying some part of the oven geometry in the axial direction.

US Patent:

60294981, Feb 29, 2000

Filed:

Jun 29, 1999

Appl. No.:

9/342368

Inventors:

David L. Walters - Northglenn CO
Scott Gaisford - Denver CO

Assignee:

MT Systems, LLC - Denver CO

International Classification:

G01N 3002

US Classification:

73 2339

Abstract:

A chromatography column for microwave heating either incorporates microwave absorbing material into the column itself or positions the column adjacent to microwave absorbing material so that the column and the chromatography sample contained therein are heated by the microwave absorbing material via conduction or convection. For example, a microwave absorbing material (e. g. , ferrite) can be fused into the inner silica layer or incorporated in an outer polymer layer of the column. Microwave absorbing material can also be incorporated into an external element (e. g. , an outer tube, sleeve, or spool) positioned adjacent to the chromatography column. A layer of thermal insulation can be placed around the column to decrease the rate of heat loss. Optionally, a gap can be provided between the chromatography column and thermal insulation to further reduce heat loss during the heating cycle and to accelerate cooling at the end of the heating cycle by making it possible to ventilate the heated column. The chromatography column assembly can be protected from overheating by selecting a microwave absorbing material having a loss factor that decreases rapidly above a predetermined maximum temperature.

US Patent:

6157015, Dec 5, 2000

Filed:

Jul 23, 1999

Appl. No.:

9/359879

Inventors:

Scott Gaisford - Denver CO
David L. Walters - Northglenn CO

Assignee:

MT Systems, LLC - Denver CO

International Classification:

H05B 680
H05B 672
G01N 3002

US Classification:

219748

Abstract:

A microwave heating apparatus is used for heating a chromatographic column assembly containing a microwave absorbing material. The microwave heating apparatus includes an antenna transmitting a microwave signal and a resonant cavity containing the chromatographic column assembly and the antenna. The chromatographic column assembly extends relative to predetermined electromagnetic field strength contours within the resonant cavity to provide a predetermined heating profile along the length of the chromatographic column assembly. For example, a single-mode chromatographic column microwave oven can be used to heat a coiled chromatography column to a desired temperature gradient along its length. Oven design embodiments utilizing coaxial transmission line structures, coaxial resonators, and cylindrical resonators are described. To control the electromagnetic field gradient in the axial direction, the oven designs provide for varying some part of the oven geometry in the axial direction.

US Patent:

59396148, Aug 17, 1999

Filed:

Jul 1, 1998

Appl. No.:

9/108297

Inventors:

David L. Walters - Westminster CO
Scott Gaisford - Denver CO

Assignee:

MT Systems, LLC - Denver CO

International Classification:

G01N 3002

US Classification:

73 2339

Abstract:

A chromatography column for microwave heating either incorporates microwave absorbing material into the column itself or positions the column adjacent to microwave absorbing material so that the column and the chromatography sample contained therein are heated by the microwave absorbing material via conduction or convection. For example, a microwave absorbing material (e. g. , ferrite) can be fused into the inner silica layer or incorporated in an outer polymer layer of the column. Microwave absorbing material can also be incorporated into an external element (e. g. , an outer tube, sleeve, or spool) positioned adjacent to the chromatography column. A layer of thermal insulation can be placed around the column to decrease the rate of heat loss. Optionally, a gap can be provided between the chromatography column and thermal insulation to further reduce heat loss during the heating cycle and to accelerate cooling at the end of the heating cycle by making it possible to ventilate the heated column. The chromatography column assembly can be protected from overheating by selecting a microwave absorbing material having a loss factor that decreases rapidly above a predetermined maximum temperature.

US Patent:

6316759, Nov 13, 2001

Filed:

Dec 1, 2000

Appl. No.:

9/729134

Inventors:

Gregory Scott Gaisford - Denver CO
David L. Walters - Fort Collins CO

Assignee:

MT Systems, LLC - Denver CO

International Classification:

H05B 680
H05B 672
G01N 3002

US Classification:

219748

Abstract:

A microwave heating apparatus is used for heating a chromatographic column assembly containing a microwave absorbing material. The microwave heating apparatus includes an antenna transmitting a microwave signal and a resonant cavity containing the chromatographic column assembly. The chromatographic column assembly extends relative to predetermined electromagnetic field strength contours within the resonant cavity to provide a predetermined heating profile along the length of the chromatographic column assembly. For example, a single-mode chromatographic column microwave oven can be used to heat a coiled chromatography column to a desired temperature gradient along its length. Oven design embodiments utilizing coaxial transmission line structures, coaxial resonators, and cylindrical resonators are described. Oven designs are provided to achieve more suitable oven size for fixed operating frequencies. Apparatuses for impedance matching an oven to a microwave source are described.

Address:

9441 W Jewell Pl, Lakewood, CO 80227

Phone:

(303)9957400

VIN:

1FTFX1EF4CFA41449

Make:

FORD

Model:

F-150

Year:

2012

Address:

7145 S Oneida Cir, Centennial, CO 80112

Phone:

(207)4505740

VIN:

WBAWV53547P076710

Make:

BMW

Model:

3 SERIES

Year:

2007