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Patent US4071427A successfully refreshed from Google Patents.
US4071427A
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Arsenite electrode
Assignee: Bank of America Illinois
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Filing: 1976-11-17
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Granted: 1978-01-31
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Expires: 1996-11-17
Abstract
Abstract An electrode sensitive to arsenite ions in solution, the ion-sensitive portion being an imporous membrane of silver arsenite and silver sulfide.
Inventors
- 👤 Kuang Lu Cheng
- 👤 Eric En-Kuang Chao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:07
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30; G01N27/333
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
35 words
In an electrode for potentiometric determination of the activity of ions in solution, an element sensitive to arsenite ions comprising a membrane of a mixture of Ag 2 S and Ag 3 AsO 3 .
Claim 2
Dependent Claim
35 words
In an electrode for potentiometric determination of the activity of ions in solution, an element sensitive to arsenite ions comprising a membrane of a mixture of Ag 2 S and Ag 3 AsO 3 .
Claim 3
Dependent Claim
15 words
An element as defined in claim 1 wherein said membrane is substantially free of silver.
Claim 4
Dependent Claim
13 words
An element as defined in claim 1 wherein said membrane is substantially imporous.
Claim 5
Dependent Claim
36 words
An element as defined in claim 1 wherein said Ag 3 AsO 3 is in proportion to said Ag 2 S in an optimum range of ratios, expressed in mole percentages, of between 1:9999 and 1:9.
Claim 6
Dependent Claim
57 words
A potentiometric system for measuring the activity of arsenite ions in a solution with a reference electrode and an ion-sensitive electrode both contacting said solution and connected to a potential measuring device, wherein said ion-sensitive electrode has as the ion-sensitive element thereof, a membrane of a mixture of Ag 2 S and Ag 3 AsO 3 .
Claim 7
Dependent Claim
57 words
A potentiometric system for measuring the activity of arsenite ions in a solution with a reference electrode and an ion-sensitive electrode both contacting said solution and connected to a potential measuring device, wherein said ion-sensitive electrode has as the ion-sensitive element thereof, a membrane of a mixture of Ag 2 S and Ag 3 AsO 3 .
Claim 8
Dependent Claim
16 words
A potentiometric system as defined in claim 5 wherein said membrane is substantially free of silver.
Claim 9
Dependent Claim
14 words
A potentiometric system as defined in claim 5 wherein said membrane is substantially imporous.
Claim 10
Dependent Claim
37 words
A potentiometric system as defined in claim 5 wherein said Ag 3 AsO 3 is in proportion to said Ag 2 S in an optimum range of ratios, expressed in mole percentages, of between 1:9999 and 1:9.
References Cited (Backward Citations)
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Cited
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Cited
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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) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |