US3881111A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for the detection of nitric oxide
Assignee: California Institute of Technology
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Filing: 1973-09-27
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Granted: 1975-04-29
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Expires: 1993-09-27
Abstract
Abstract A method and apparatus for detecting the presence and quantity of nitric oxide is disclosed. A volume of gas being evaluated for the presence and quantity of nitric oxide is illuminated by a source of ultraviolet radiation to produce ionization of any nitric oxide present. Resulting nitric oxide ions are detected by means of an ion detection system. The source of ultraviolet radiation may be either a window or windowless device.
Inventors
- 👤 James B Stephens
- 👤 Parameswar Mahadevan
- 👤 Raymond L Chuan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:34
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/003; G; G01; G01N; G01N27/00; G01N27/62; G01N27/64; F23N1/00; F23N1/02
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
78 words
APPARATUS FOR DECTING THE PRESENCE OF OXIDES OF NITROGEN COMPRISING: A SOURCE OF ULTRAVIOLET RADIATION FOR IONIZING OXIDES OF NITROGEN ILLUMINATED THEREBY, AN ION DETECTOR POSITIONED TO COLLECT IONS OF SAID OXIDES OF NITROGEN, AND BAFFLE MEANS INCLUDING FIRST AND SECOND SECTIONS, SAID SECOND SECTION POSITIONED FOR SHIELDING SAID ION DETECTOR FROM DIRECT INCIDENCE OF ULTRAVIOLET RADIATION FROM SAID SOURCE, SAID FIRST SECTION POSITIONED TO ELECTRICALLY SHIELD SAID SECOND SECTION FROM SAID IONS OF SAID OXIDES OF NITROGEN.
Claim 2
Dependent Claim
78 words
APPARATUS FOR DECTING THE PRESENCE OF OXIDES OF NITROGEN COMPRISING: A SOURCE OF ULTRAVIOLET RADIATION FOR IONIZING OXIDES OF NITROGEN ILLUMINATED THEREBY, AN ION DETECTOR POSITIONED TO COLLECT IONS OF SAID OXIDES OF NITROGEN, AND BAFFLE MEANS INCLUDING FIRST AND SECOND SECTIONS, SAID SECOND SECTION POSITIONED FOR SHIELDING SAID ION DETECTOR FROM DIRECT INCIDENCE OF ULTRAVIOLET RADIATION FROM SAID SOURCE, SAID FIRST SECTION POSITIONED TO ELECTRICALLY SHIELD SAID SECOND SECTION FROM SAID IONS OF SAID OXIDES OF NITROGEN.
Claim 3
Dependent Claim
14 words
The apparatus defined by claim 1, said oxides of nitrogen being primarily nitric oxide.
Claim 4
Dependent Claim
25 words
The apparatus defined by claim 1, said source of ultraviolet radiation providing electromagnetic radiation having a wavelength in the range of 1,200 to 1,300 angstroms.
Claim 5
Dependent Claim
48 words
The apparatus defined by claim 1, said ion detector including: probe means for collecting ions of said oxides of nitrogen; means for maintaining said probe means at a negative potential; and means connected to said probe means for providing an indication of ions collected by said probe means.
Claim 6
Dependent Claim
18 words
The apparatus defined by claim 1, said source of ultraviolet radiation including means for providing a hydrogen arc.
Claim 7
Dependent Claim
50 words
The apparatus defined by claim 5, said means for producing a hydrogen arc including: a source of hydrogen gas; means for feeding said hydrogen gas from said source to a pair of electrodes between which an arc is found; and means for maintaining a predetermined electrical potential between said electrodes.
Claim 8
Dependent Claim
48 words
The apparatus defined by claim 6, said ion detector including: probe means for collecting ions of said oxides of nitrogen; means for maintaining said probe means at a negative potential; and means connected to said probe means for providing an indication of ions collected by said probe means.
Claim 9
Dependent Claim
38 words
The apparatus defined by claim 7, said baffle means being positioned for confining the plasma attendant to said hydrogen arc, said baffle means ducting excess hydrogen gas and hydrogen ions past said probe means and in isolation therefrom.
Claim 10
Dependent Claim
25 words
The apparatus defined by claim 8, said source of ultraviolet radiation providing electroMagnetic radiation having a wavelength in the range of 1,200 to 1,300 angstroms.
Claim 11
Dependent Claim
52 words
The apparatus defined by claim 1, said ion detector including a probe configured to form a central opening, said source including a hydrogen arc, said first and second sections extending through said central opening of said probe to direct excess hydrogen gas and hydrogen ions past said probe and in isolation therefrom.
Claim 12
Dependent Claim
22 words
The apparatus defined by claim 10, said first and second sections being tubular, said second section being positioned within the first section.
Claim 13
Dependent Claim
27 words
The apparatus defined by claim 11, said first section being connected to be maintained electrically positive and said second section being connected to be maintained electrically negative.
Claim 14
Dependent Claim
44 words
The apparatus defined by claim 10, said second section including: a solid portion positioned for shielding said probe from direct incidence of ultraviolet radiation from said source; and a non-solid portion transmissive to ultraviolet radiation for confining the plasma attendant to said hydrogen arc.
Claim 15
Dependent Claim
71 words
The apparatus defined by claim 13, said first and second sections being tubular wherein said second section is axially positioned within said first section, said second section including a solid tubular position and a porous tubular portion both connected to be maintained electrically negative, said first section being porous and connected to be electrically positive, said first section electrically shielding said second section from positive ions of said oxides of nitrogen.
Claim 16
Dependent Claim
82 words
A nitric oxide detector adapted for placement in a duct through which gases are passed, said detector including: source means for irradiating said gases with ultraviolet radiation to ionize nitric oxide forming a part thereof to produce nitric oxide ions; collector means for collecting said nitric oxide ions; and baffle means including an inner section for preventing direct irradiation of said collector means by said ultraviolet radiation, and an outer section for electrically isolating said inner section from said nitric oxide ions.
Claim 17
Dependent Claim
82 words
A nitric oxide detector adapted for placement in a duct through which gases are passed, said detector including: source means for irradiating said gases with ultraviolet radiation to ionize nitric oxide forming a part thereof to produce nitric oxide ions; collector means for collecting said nitric oxide ions; and baffle means including an inner section for preventing direct irradiation of said collector means by said ultraviolet radiation, and an outer section for electrically isolating said inner section from said nitric oxide ions.
Claim 18
Dependent Claim
27 words
The nitric oxide detector defined in claim 15 further including means for providing a quantitative indication of the nitric oxide ions collected by said means for collecting.
Claim 19
Dependent Claim
28 words
The nitric oxide detector defined by claim 15, said source means including a source of ultraviolet radiation having a wavelength in the range of 1,200 to 1,300 angstroms.
Claim 20
Dependent Claim
33 words
The nitric oxide detector defined by claim 17, said source of ultraviolet radiation including an enclosed lamp having a transparent window through which said radiation is directed to ionize nitric oxide illuminated thereby.
Claim 21
Dependent Claim
20 words
The nitric oxide detector defined by claim 17, said source of ultraviolet radiation including means for producing a hydrogen arc.
Claim 22
Dependent Claim
48 words
The nitric oxide detector defined by claim 19, said source being positioned within said inner section, the plasma attendant to said hydrogen arc being confined by said inner section, excess hydrogen gas and ions being ducted by said baffle means past said collector means and in isolation therefrom.
Claim 23
Dependent Claim
27 words
The nitric oxide detector defined by claim 20, said inner and outer sections being tubular, said inner section being positioned within the core of said outer section.
Claim 24
Dependent Claim
32 words
The nitric oxide detector defined by claim 21, said inner section including a solid portion and a porous portion, said outer section being porous to allow the propagation of ultraviolet radiation therethrough.
Claim 25
Dependent Claim
28 words
The nitric oxide detector defined in claim 22, said inner section being connected to be maintained electrically negative, said outer section being connected to be maintained electrically positive.
Claim 26
Dependent Claim
48 words
The nitric oxide detector defined by claim 17 further including: means for providing a quantitative indication of the nitric oxide ions collected by said means for collecting said nitric oxide ions; and mEans for maintaining said means for collecting said nitric oxide ions at a predetermined negative potential.
Claim 27
Dependent Claim
31 words
The nitric oxide detector defined by claim 15, said inner and outer sections being respectively connected to be electrically negative and positive, said inner section being positioned within said outer section.
Claim 28
Dependent Claim
27 words
The nitric oxide detector defined by claim 15, said collector means being configured to form a central aperture, said inner and outer sections extending through said aperture.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |