US4317035A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gold monitoring procedure
Assignee: AT&T Inc
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Filing: 1979-12-20
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Granted: 1982-02-23
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Expires: 1999-12-20
Abstract
Abstract A gold plating process is described in which gold concentration is monitored by a radioactive excitation procedure. This procedure for measuring gold concentration requires no chemical manipulation and yields immediate results. The procedure can be adapted to continuous concentration measurement for use in automatic control of gold concentration in a gold plating procedure.
Inventors
- 👤 Richard L. Cohen
- 👤 Ronald L. Meek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:09
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/22; G01N23/223; G01N2223/00; G01N2223/07; G01N2223/076
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
66 words
A process for plating gold from a gold plating solution including the step of measuring gold concentration in the gold plating solution characterized in that the gold concentration is measured by exposing the gold plating solution to radiation from a radioactive source emitting photons of sufficiently high energy to excite X-ray fluorescence from the gold and detecting the resulting X-ray fluorescence with a solid state detector.
Claim 2
Dependent Claim
66 words
A process for plating gold from a gold plating solution including the step of measuring gold concentration in the gold plating solution characterized in that the gold concentration is measured by exposing the gold plating solution to radiation from a radioactive source emitting photons of sufficiently high energy to excite X-ray fluorescence from the gold and detecting the resulting X-ray fluorescence with a solid state detector.
Claim 3
Dependent Claim
23 words
The process of claim 1 in which the radioactive source is selected from the group consisting of Co 57 and Eu 155 .
Claim 4
Dependent Claim
19 words
The process of claim 1 in which the excitation energy from the radioactive source is greater than 81 keV.
Claim 5
Dependent Claim
15 words
The process of claim 1 in which the solid state detector is a germanium detector.
Claim 6
Dependent Claim
15 words
The process of claim 4 in which the germanium detector is cooled below room temperature.
Claim 7
Dependent Claim
16 words
The process of claim 5 in which the germanium detector is cooled to liquid nitrogen temperatures.
Claim 8
Dependent Claim
32 words
The process of claim 1 in which the energy band of the X-ray fluorescence for gold is selected by means of pulse height selection of the output of the solid state detector.
Claim 9
Dependent Claim
15 words
The process of claim 7 in which the fluorescence lines selected are the K lines.
Claim 10
Dependent Claim
13 words
The process of claim 1 in which a plastic sample vial is used.
Claim 11
Dependent Claim
14 words
The process of claim 9 in which the sample vial is made of polyethylene.
Claim 12
Dependent Claim
19 words
The process of claim 1 in which the measurement of gold concentration is made on a continuously flowing solution.
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) | 1985-02-22 | 1985-08-24 | 1986-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-02-22 | 1989-08-24 | 1990-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-02-22 | 1993-08-24 | 1994-02-23 | $7700.00 | Window Closed / Lapsed |