US5268972A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aromatic hydrocarbon optrodes for groundwater monitoring applications
Assignee: United States Department of the Air Force
•
Filing: 1992-02-12
•
Granted: 1993-12-07
•
Expires: 2012-02-12
Abstract
Abstract Fiber optic based optrodes suitable for in-situ monitoring of groundwater and earth material for the presence of aromatic hydrocarbons. The optrodes are fabricated with porous optical waveguides which are impregnated with a chemical indicator whose optical transmission properties change in the presence of aromatic species, providing a high degree of chemical specificity.
Inventors
- 👤 Mary E. Tabacco
- 👤 Bruce J. Nielsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:26
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/75; G01N21/77; G01N21/7703; G01N2021/7706; G01N2021/7709; G01N2021/7713; G01N2021/773; G01N21/84; G01N21/85; G01N21/8507; G01N2021/8528; G01N2021/855
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
68 words
In an optrode for in situ monitoring of chemical species wherein said optrode comprises a borosilicate optical fiber provided with a porous segment cast with a sensing reagent, the improvement wherein said chemical species comprise aromatic hydrocarbons and said sensing reagent is characterized by a sensitivity to less than 50 ppb, a response time less than 1 minute, excellent reproducibility and linearity, and specificity for said aromatic hydrocarbons.
Claim 2
Dependent Claim
68 words
In an optrode for in situ monitoring of chemical species wherein said optrode comprises a borosilicate optical fiber provided with a porous segment cast with a sensing reagent, the improvement wherein said chemical species comprise aromatic hydrocarbons and said sensing reagent is characterized by a sensitivity to less than 50 ppb, a response time less than 1 minute, excellent reproducibility and linearity, and specificity for said aromatic hydrocarbons.
Claim 3
Dependent Claim
18 words
The improved optrode of claim 1 wherein said aromatic hydrocarbons are those comprising the simple components of fuel.
Claim 4
Dependent Claim
22 words
The improved optrode of claim 2 wherein said aromatic hydrocarbons are selected from the group consisting of benzene, toluene, ethylbenzene and xylene.
Claim 5
Dependent Claim
11 words
the improved optrode of claim 3 wherein said reagent is TCNE.
Claim 6
Dependent Claim
28 words
The improved optrode of claim 1 wherein said sensing reagent is selected from the group consisting of TCNQ, fluorescein, AgNO 3 , maleic anhydride, I 2 and TCNE.
Claim 7
Dependent Claim
20 words
The improved optrode of claim 1 wherein said reagent is capable of forming a π-type complex with said aromatic hydrocarbons.
References Cited (Backward Citations)
US4846548A
Cited
US5109442A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-06 | 1997-06-07 | 1997-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-06 | 2001-06-07 | 2001-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-06 | 2005-06-07 | 2005-12-07 | $7700.00 | Window Closed / Lapsed |