Patent US4220515A successfully refreshed from Google Patents.
US4220515A
Expired / Lapsed
US
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Apparatus for automatically determining the amount of one or more substances in a liquid
Assignee: C Alewijnse & Co Bv
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Filing: 1978-11-27
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Granted: 1980-09-02
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Expires: 1998-11-27
Abstract
Abstract A method for automatically determining the amount of one or more substances by stripping voltammetry, said amount ranging from 10 -9 to 10 -5 mol/l (0.1-1000 microgrammes per liter) according to an automatically repeating programme is carried out continuously, not batch-wise, for a time span of a month or more. An apparatus implementing said method preferably comprises a hanging drop electrode and means to renew the hanging drop at the start of each determination. Pretreatment of a physical and/or chemical nature is carried through continuously outside the stripping range. (FIG. 1).
Inventors
- 👤 Casper W. de Kreuk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:42
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/42
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
173 words
Apparatus for automatically determining the amount of one or more substances in a liquid by stripping voltammetry, comprising: a measuring cell; electrode support means disposed in the measuring cell for supporting a drop of mercury therein as a hanging drop electrode; a feeding system for delivering liquid to the measuring cell for testing and for delivering mercury in doses to the electrode support means, said feeding system including a pretreatment chamber in which liquid undergoes pretreatment prior to being delivered to the measuring cell for testing; a discharge system for removing the liquid from the measuring cell after testing; a magnetic stirring device for stirring the liquid in the measuring cell; a knocking device for knocking the measuring cell thereby to detach the mercury drop from the electrode support means, the deteached mercury drop leaving the cell with the liquid by way of the discharge system; and a programming circuit for automatically controlling operation of the apparatus, said programming circuit being connected to control operation of the stirring device and the knocking device.
Claim 2
Dependent Claim
173 words
Apparatus for automatically determining the amount of one or more substances in a liquid by stripping voltammetry, comprising: a measuring cell; electrode support means disposed in the measuring cell for supporting a drop of mercury therein as a hanging drop electrode; a feeding system for delivering liquid to the measuring cell for testing and for delivering mercury in doses to the electrode support means, said feeding system including a pretreatment chamber in which liquid undergoes pretreatment prior to being delivered to the measuring cell for testing; a discharge system for removing the liquid from the measuring cell after testing; a magnetic stirring device for stirring the liquid in the measuring cell; a knocking device for knocking the measuring cell thereby to detach the mercury drop from the electrode support means, the deteached mercury drop leaving the cell with the liquid by way of the discharge system; and a programming circuit for automatically controlling operation of the apparatus, said programming circuit being connected to control operation of the stirring device and the knocking device.
Claim 3
Dependent Claim
149 words
Apparatus as claimed in claim 1, wherein the feeding system includes a pretreatment chamber in which liquid undergoes pretreatment for elimination of oxygen from the liquid, said pretreatment chamber being bounded by a cylindrical wall and two opposite end faces, and being provided with a feeder opening and a discharge opening for nitrogen arranged along a generatrix of the cylindrical wall near the end faces respectively of the chamber, a feeder opening and a discharge opening for the liquid to be pretreated arranged substantially diametrically opposite to the openings for nitrogen, and an overflow opening for liquid in one end face, so that by placing the chamber with the central axis of the cylindrical wall inclined to the horizontal a film of liquid is able to flow from the feeder opening for liquid to the discharge opening for liquid and to the overflow in counterflow to a nitrogen stream.
Claim 4
Dependent Claim
18 words
Apparatus as claimed in claim 1 or 2, wherein the electrode support means are formed from plastics material.
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) | 1983-09-02 | 1984-03-03 | 1984-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-02 | 1988-03-03 | 1988-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-02 | 1992-03-03 | 1992-09-02 | $7700.00 | Window Closed / Lapsed |