Xiang Liu

US Patent:

7704301, Apr 27, 2010

Filed:

Apr 11, 2008

Appl. No.:

12/101890

Inventors:

Xin Zhou - Rancho Cucamonga CA, US
Xiang Liu - Phoenix AZ, US
Alfred Feitisch - Los Gatos CA, US
Gregory M. Sanger - Chico CA, US

Assignee:

SpectraSensors, Inc. - Rancho Cucamonga CA

International Classification:

B01D 59/26

US Classification:

95 90, 95136, 95235, 96413, 73 232, 73 2321, 73 2323, 73863, 423210, 702 24

Abstract:

A differential absorption spectrum for a reactive gas in a gas mixture can be generated for sample absorption data by subtracting background absorption data set from the sample absorption data. The background absorption data can be characteristic of absorption characteristics of the background composition in a laser light scan range that includes a target wavelength. The differential absorption spectrum can be converted to a measured concentration of the reactive gas using calibration data. A determination can be made whether the background composition has substantially changed relative to the background absorption data, and new background absorption data can be used if the background composition has substantially changed. Related systems, apparatus, methods, and/or articles are also described.

US Patent:

7728978, Jun 1, 2010

Filed:

Oct 17, 2007

Appl. No.:

11/873723

Inventors:

Xin Zhou - Rancho Cucamonga CA, US
Xiang Liu - Phoenix AZ, US
Gregory M. Sanger - Chico CA, US

Assignee:

SpectraSensors, Inc. - Rancho Cucamonga

International Classification:

G01N 21/00
G01N 21/37

US Classification:

356437, 356436, 250343

Abstract:

Moisture can be detected in a refrigerant background such as HFC (Hydrofluorocarbon) HFC-134A and HFC-152A and exampled by HFC-23, HFC-32, HFC-143A, HFC-125, HFC-245FA, HFC-227EA, and the like. The system can include a light source operating at any one of several wavelengths within the water absorption bands at wavelengths such as 1. 4, 1. 9 and 2. 7 μm and a detector that measures the transmitted light intensity through the HFC samples. In one variation, the light source is a tunable diode laser and the moisture level is determined by direct absorption and harmonic spectroscopy. Related techniques, apparatus, systems, and articles are also described.

US Patent:

7819946, Oct 26, 2010

Filed:

Apr 19, 2010

Appl. No.:

12/763124

Inventors:

Xin Zhou - Rancho Cucamonga CA, US
Xiang Liu - Phoenix AZ, US
Alfred Feitisch - Los Gatos CA, US
Gregory M. Sanger - Chico CA, US

Assignee:

SpectraSensors, Inc. - Rancho Cucamonga CA

International Classification:

B01D 59/26

US Classification:

95 90, 95136, 95235, 96413, 73 232, 73 2321, 73 2323, 73863, 423210, 702 24

Abstract:

A differential absorption spectrum for a reactive gas in a gas mixture can be generated for sample absorption data by subtracting background absorption data set from the sample absorption data. The background absorption data can be characteristic of absorption characteristics of the background composition in a laser light scan range that includes a target wavelength. The differential absorption spectrum can be converted to a measured concentration of the reactive gas using calibration data. A determination can be made whether the background composition has substantially changed relative to the background absorption data, and new background absorption data can be used if the background composition has substantially changed. Related systems, apparatus, methods, and/or articles are also described.

US Patent:

7829046, Nov 9, 2010

Filed:

Aug 29, 2008

Appl. No.:

12/202098

Inventors:

Marc M. Baum - Arcadia CA, US
John Moss - Los Angeles CA, US
Xin Zhou - Rancho Cucamonga CA, US
Alex Kwan - Chino Hills CA, US
Alfred Feitisch - Los Gatos CA, US
Xiang Liu - Rancho Cucamonga CA, US

Assignee:

SpectraSensors, Inc. - Rancho Cucamonga CA

International Classification:

B01D 47/00
B01J 38/12

US Classification:

423210, 502 38

Abstract:

Scrubber media for reactive gases, that can include but are not necessarily limited to hydrogen chloride (HCl), hydrogen sulfide (HS), hydrogen fluoride (HF), and ammonia (NH), can include reactive particles, potentially as small as nano-scale, that can optionally be suspended on macro-scale carrier particles. Reactive gases can be converted to non-volatile compounds by being passed through a bed of such scrubber media. Such scrubber media can be used to remove reactive gases from gas mixtures. Potential applications include differential absorption spectroscopy, air pollutant emission controls, and the like. Methods of preparing scrubber media are also described.

US Patent:

8152900, Apr 10, 2012

Filed:

Oct 25, 2010

Appl. No.:

12/911666

Inventors:

Xin Zhou - Rancho Cucamonga CA, US
Xiang Liu - Phoenix AZ, US
Alfred Feitisch - Los Gatos CA, US
Gregory M. Sanger - Chico CA, US

Assignee:

SpectraSensors, Inc. - Rancho Cucamonga CA

International Classification:

B01D 59/26

US Classification:

95 90, 95136, 95235, 96413, 423210, 73 232, 73 2321, 73 2323, 73863, 702 24

Abstract:

A differential absorption spectrum for a reactive gas in a gas mixture can be generated for sample absorption data by subtracting background absorption data set from the sample absorption data. The background absorption data can be characteristic of absorption characteristics of the background composition in a laser light scan range that includes a target wavelength. The differential absorption spectrum can be converted to a measured concentration of the reactive gas using calibration data. A determination can be made whether the background composition has substantially changed relative to the background absorption data, and new background absorption data can be used if the background composition has substantially changed. Related systems, apparatus, methods, and/or articles are also described.

US Patent:

8500849, Aug 6, 2013

Filed:

Mar 23, 2012

Appl. No.:

13/428626

Inventors:

Xin Zhou - Rancho Cucamonga CA, US
Xiang Liu - Phoenix AZ, US
Alfred Feitisch - Los Gatos CA, US
Gregory M. Sanger - Chico CA, US

Assignee:

SpectraSensors, Inc. - Rancho Cucamonga CA

International Classification:

B01D 59/26

US Classification:

95 90, 95136, 95235, 96413, 423210, 73 232, 73 2321, 73 2323, 73863, 702 24

Abstract:

A differential absorption spectrum for a reactive gas in a gas mixture can be generated for sample absorption data by subtracting background absorption data set from the sample absorption data. The background absorption data can be characteristic of absorption characteristics of the background composition in a laser light scan range that includes a target wavelength. The differential absorption spectrum can be converted to a measured concentration of the reactive gas using calibration data. A determination can be made whether the background composition has substantially changed relative to the background absorption data, and new background absorption data can be used if the background composition has substantially changed. Related systems, apparatus, methods, and/or articles are also described.

US Patent:

20120099109, Apr 26, 2012

Filed:

Sep 16, 2011

Appl. No.:

13/235105

Inventors:

Xiang Liu - Rancho Cucamonga CA, US
John Lewison - Corona CA, US
Wenhai Ji - Fontana CA, US
Alfred Feitisch - Rancho Cucamonga CA, US

International Classification:

G01N 21/00

US Classification:

356437

Abstract:

A reference harmonic absorption curve of a laser absorption spectrometer, which can include a tunable or scannable laser light source and a detector, can have a reference curve shape and can include a first, second, or higher order harmonic signal of a reference signal generated by the detector in response to light passing from the laser light source through a reference gas or gas mixture. The reference gas or gas mixture can include one or more of a target analyte and a background gas expected to be present during analysis of the target analyte. The reference harmonic absorption curve can have been determined for the laser absorption spectrometer in a known or calibrated state. A test harmonic absorption curve having a test curve shape is compared with the reference harmonic absorption curve to detect a difference between the test curve shape and the reference curve shape that exceeds a predefined allowed deviation and therefore indicates a change in an output of the laser light source relative to the known or calibrated state. One or more operating and/or analytical parameters of the laser absorption spectrometer are adjusted to correct the test curve shape to reduce the difference between the test curve shape and the reference curve shape.

US Patent:

20230065553, Mar 2, 2023

Filed:

Aug 25, 2021

Appl. No.:

17/445880

Inventors:

- Rancho Cucamonga CA, US
Xiang Liu - Rancho Cucamonga CA, US
Thomas Wilhelm - Chemnitz, DE

International Classification:

G01N 21/64
G01N 21/39
G01N 21/17

Abstract:

The present disclosure relates to a device for measuring a first analyte concentration and a second analyte concentration in a measuring medium, the device including: a sample cell; a first light source unit; a first detector unit; a functional element; a second light source unit; a second detector unit; and a control unit adapted to analyze a detected first light for determining a first value representing the concentration of the first analyte in the measuring medium and adapted to analyze a detected third light for determining a second value representing the concentration of the second analyte in the measuring medium. A method of using the device is also disclosed.