US4177318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spectroscopy
Assignee: British Steel Corp
•
Filing: 1977-07-25
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Granted: 1979-12-04
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Expires: 1997-07-25
Abstract
Abstract A graphite electrode for use in spectroscopic analysis in which at least the region of the electrode intended for contact with the material to be analyzed has a layer comprising the heat reaction product of graphite with a salt of a refractory metal and a salt of an alkali earth metal.
Inventors
- 👤 Ernald V. Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:56
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/62; G01N21/71; G01N21/74; Y; Y10; Y10T; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
62 words
A graphite electrode for use in spectrospopic analysis in which at least the region of the electrode intended for contact with the material to be analysed has a layer comprising the heat reaction product of graphite with a salt of a refractory metal selected from the group consisting of zirconium vanadium, molybdenum, and lanthanum and a salt of an alkali earth metal.
Claim 2
Dependent Claim
62 words
A graphite electrode for use in spectrospopic analysis in which at least the region of the electrode intended for contact with the material to be analysed has a layer comprising the heat reaction product of graphite with a salt of a refractory metal selected from the group consisting of zirconium vanadium, molybdenum, and lanthanum and a salt of an alkali earth metal.
Claim 3
Dependent Claim
19 words
A graphite electrode as claimed in claim 1 wherein the reaction product includes a carbide/nitride of the refractory metal.
Claim 4
Dependent Claim
17 words
A graphite electrode as claimed in claim 1 wherein the alkali earth metal is calcium or magnesium.
Claim 5
Dependent Claim
20 words
A graphite electrode as claimed in claim 3 wherein the salt of the alkali earth metal is a metal nitrate.
Claim 6
Dependent Claim
14 words
A graphite electrode as claimed in claim 4 wherein the salt is calcium nitrate.
Claim 7
Dependent Claim
22 words
A graphite electrode as claimed in claim 5 wherein the calcium nitrate is in the form of calcium carbonate in nitric acid.
Claim 8
Dependent Claim
19 words
A graphite electrode as claimed in claim 6, wherein the salt of the refractory metal is a metal nitrate.
Claim 9
Dependent Claim
14 words
A graphite electrode as claimed in claim 7 wherein the salt is zirconium nitrate.
Claim 10
Independent Claim
68 words
A method for producing a graphite electrode for spectroscopic analysis comprising treating at least the region of the electrode intended for contact with the material to be analysed with the salt of a refractory metal selected from the group consisting of zirconium, vanadium, molybdenum and lanthanum and the salt of an alkali earth metal and heating the treated graphite to a temperature producing a reaction with the salt.
Claim 11
Independent Claim
68 words
A method for producing a graphite electrode for spectroscopic analysis comprising treating at least the region of the electrode intended for contact with the material to be analysed with the salt of a refractory metal selected from the group consisting of zirconium, vanadium, molybdenum and lanthanum and the salt of an alkali earth metal and heating the treated graphite to a temperature producing a reaction with the salt.
Claim 12
Dependent Claim
15 words
A method as claimed in claim 9 wherein the heating is in an inert ambient.
Claim 13
Dependent Claim
14 words
A method as claimed in claim 10 wherein the ambient contains a reducing component.
Claim 14
Dependent Claim
16 words
A method as claimed in claim 9 wherein heating is by electric current through the graphite.
Claim 15
Dependent Claim
18 words
A method as claimed in claim 9 wherein the salt of the refractory metal is a metal nitrate.
Claim 16
Dependent Claim
21 words
A method as claimed in claim 9 wherein the alkali earth metal is selected from the group including calcium and magnesium.
Claim 17
Dependent Claim
19 words
A method as claimed in claim 14 wherein the salt of the alkali earth metal is a metal nitrate.
Claim 18
Dependent Claim
11 words
A graphite electrode when produced by the method of claim 9.
References Cited (Backward Citations)
US3342627A
Cited
US3939028A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-12-03 | 1983-06-04 | 1983-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-03 | 1987-06-04 | 1987-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-03 | 1991-06-04 | 1991-12-04 | $7700.00 | Window Closed / Lapsed |