US3569703A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for assaying solutions containing alpha-emitting isotopes using track-registration material
Assignee: General Electric Co
•
Filing: 1968-02-26
•
Granted: 1971-03-09
•
Expires: 1988-02-26
Abstract
Abstract A method for determining the quantity of an alpha-emitting ingredient in a solution. A sheet of track-registration material is brought into close proximity to the solution, held there for given period of time, and then removed. This material has the characteristic of forming damage tracks along paths traversed by alpha particles. These paths may be enlarged and made visible by treatment with a suitable etchant which enlarges the tracks. The number of tracks formed in a given area is an indication of the quantity of the alpha-emitting ingredient present in the solution.
Inventors
- 👤 Henry Ward Alter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:39
CPC Classifications
G; G01; G01T; G01T5/00; G01T5/10; G01T1/00; G01T1/16; G01T1/17; G01T1/178
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
38 words
The method of claim 1 wherein said material is positioned in close proximity to said solution by enclosing said material in a solution-impermeable film which is substantially transparent to alpha-radiation and dipping the enclosed material in said solution.
Claim 2
Dependent Claim
42 words
The method of claim 2 wherein said film forms a bag having an open top extending above the solution surface which permits air to be forced out of the bag by the solution whereby the bag is pressed tightly against said material.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein said material comprises cellulose nitrate.
Claim 4
Dependent Claim
24 words
The method of claim 4 wherein said material is in the form of a sheet having a thickness of at least about 50 microns.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein said material is etched in a solution comprising sodium hydroxide.
Claim 6
Dependent Claim
104 words
An article for measuring the concentration of an alpha-particle emitting ingredient in a solution which comprises: a. an open-topped bag of a material which is impermeable to said solution but permeable to alpha-particles, said bag having an average wall thickness of less than about 20 microns; b. within said bag, at the closed bottom thereof, a member having a density greater than that of said solution; and c. within said bag a sheet of track-registration material; said material being substantially insensitive to light, beta and gamma radiation and having the property of forming damage tracks along paths in said material traversed by alpha particles.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |