Patent US4138322A successfully refreshed from Google Patents.
US4138322A
Expired / Lapsed
US
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Polarographic apparatus
Assignee: University of Strathclyde
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Filing: 1977-07-12
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Granted: 1979-02-06
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Expires: 1997-07-12
Abstract
Abstract A polarographic analysis cell is described for analysis of a continuously flowing stream of liquid using a dropping mercury cathode technique. In a cell having an inlet and an outlet for throughflow of liquid, a shielded dropping mercury cathode is mounted, the cathode shield having the configuration of a funnel having an upper cup portion and a lower stem portion, the lower extremity of the stem terminating in a laterally-directed orifice which prevents entry into the shield of gas bubbles issuing from a gas diffuser also provided in the cell to diffuse deoxygenating inert gas into the cell during use.
Inventors
- 👤 David Barnes
- 👤 Champa H. Metters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:36
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30; G01N27/34; G01N27/416; G01N27/48
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
204 words
Apparatus for use in the continuous polarographic analysis of a flowing stream of liquid including, a cell having a floor, liquid inlet means opening into the cell above the floor and liquid outlet means located above the said inlet means; means connected to the inlet means for effecting flow of liquid to be analysed through the cell; a dropping mercury cathode extending into the cell, said cathode having an end portion terminating in a mercury-discharge tip directed towards said floor; an open-ended tubular cathode shield surrounding the end portion of the cathode and located in the cell at a level intermediate the said inlet and outlet means, said shield having an upper cup portion and a lower stem portion, means on the stem portion defining a laterally-directed terminal orifice, said orifice having a cross-sectional area less than that of the stem portion; support means for said shield and said cathode, said support means permitting relative displacement of the shield and cathode whereby the extent of insertion of the cathode end portion into the shield is adjustable; means supplying mercury to the cathode and discharging used mercury from the cell; and anode within the cell; and electrical conductor means associated with said anode and cathode.
Claim 2
Dependent Claim
204 words
Apparatus for use in the continuous polarographic analysis of a flowing stream of liquid including, a cell having a floor, liquid inlet means opening into the cell above the floor and liquid outlet means located above the said inlet means; means connected to the inlet means for effecting flow of liquid to be analysed through the cell; a dropping mercury cathode extending into the cell, said cathode having an end portion terminating in a mercury-discharge tip directed towards said floor; an open-ended tubular cathode shield surrounding the end portion of the cathode and located in the cell at a level intermediate the said inlet and outlet means, said shield having an upper cup portion and a lower stem portion, means on the stem portion defining a laterally-directed terminal orifice, said orifice having a cross-sectional area less than that of the stem portion; support means for said shield and said cathode, said support means permitting relative displacement of the shield and cathode whereby the extent of insertion of the cathode end portion into the shield is adjustable; means supplying mercury to the cathode and discharging used mercury from the cell; and anode within the cell; and electrical conductor means associated with said anode and cathode.
Claim 3
Dependent Claim
30 words
Apparatus as claimed in claim 1, wherein said means defining a laterally-directed terminal orifice on the stem portion is a tapered and laterally curved end portion of the stem portion.
Claim 4
Dependent Claim
24 words
Apparatus according to claim 2, including means for introducing a chemical reagent into the liquid prior to passage of the liquid into the cell.
Claim 5
Dependent Claim
22 words
Apparatus according to claim 1 in which means for deaerating liquid prior to passage of the liquid into the cell are provided.
Claim 6
Dependent Claim
24 words
Apparatus according to claim 4, including means for introducing a chemical reagent into the liquid prior to passage of the liquid into the cell.
Claim 7
Dependent Claim
21 words
Apparatus according to claim 1 in which a peristaltic pump provides the means for effecting flow of liquid through the cell.
Claim 8
Dependent Claim
24 words
Apparatus according to claim 6, including means for introducing a chemical reagent into the liquid prior to passage of the liquid into the cell.
Claim 9
Dependent Claim
24 words
Apparatus according to claim 1, including means for introducing a chemical reagent into the liquid prior to passage of the liquid into the cell.
Claim 10
Dependent Claim
65 words
Apparatus according to claim 1, in which the shield is of circular cross-section throughout, the cup portion has a diameter of 0.75 centimeters and the stem portion an internal bore of 0.32 centimeters, the dropping mercury cathode having an external diameter of 0.315 centimeters thus forming a gap between cathode and shield of 0.5 mm, and the overall length of the shield is 2.0 centimeters.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-05 | 1982-08-07 | 1983-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-05 | 1986-08-07 | 1987-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-05 | 1990-08-07 | 1991-02-06 | $7700.00 | Window Closed / Lapsed |