Patent US3681027A successfully refreshed from Google Patents.
US3681027A
Expired / Lapsed
US
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Colorimetric indicator for the detection of nitrogen dioxide
Assignee: Resource Control Inc
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Filing: 1971-05-28
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Granted: 1972-08-01
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Expires: 1991-05-28
Abstract
Abstract A SMALL, POCKET TYPE OF "FIELD USE" INDICATOR OF THE COLORIMETRIC TYPE FOR DETECTING AND INDICATING NITROGEN DIOXIDE CONTAMINATION IN AN ATMOSPHERE, IN WHICH A POWDER COMPACT OF DIAZOTIZING, COUPLING AND STABILIZING AGENTS IS MECHANICALLY SUPPORTED IN SUITABLE MANNER TO PROVIDE A SELF-CONTAINED, ONE-TIME INDICATOR UNIT THAT IS DISCARDED AFTER USE.
Inventors
- 👤 Avery B Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:53
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/75; G01N21/77; G01N21/78; Y; Y10; Y10S; Y10S436/00; Y10S436/902; Y10T; Y10T436/00; Y10T436/17; Y10T436/177692; Y10T436/178459
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |