US4053772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Locating underground uranium deposits
Assignee: Westinghouse Electric Corp
•
Filing: 1976-06-30
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Granted: 1977-10-11
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Expires: 1996-06-30
Abstract
Abstract Underground uranium deposits are located by placing pairs of dosimeters each about 5 to 18 mg/cm 2 thick underground in a grid pattern. Each dosimeter contains a phosphor which is capable of storing the energy of alpha particles. In each pair one dosimeter is shielded from alpha particles with more than 18 mg/cm 2 thick opaque material but not gamma and beta rays and the other dosimeter is shielded with less than 1 mg/cm 2 thick opaque material to exclude dust. After a period underground the dosimeters are heated which releases the stored energy as light. The amount of light produced from the heavily shielded dosimeter is subtracted from the amount of light produced from the thinly shielded dosimeter to give an indication of the location and quantity of uranium underground.
Inventors
- 👤 Patrick E. Felice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:33
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/04; G01V5/06; G01T; G01T1/00; G01T1/02; G01T1/10; G01T1/11; Y; Y10; Y10S; Y10S250/00; Y10S250/02
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
61 words
A method of locating underground deposits of uranium comprising A. placing underground a dosimeter in the form of a thin layer about 5 to about 18 mg/cm 2 thick which is capable of storing energy from alpha particles: B. activating said dosimeter to cause it to release said stored energy from alpha particles; and C. measuring the amount of energy released.
Claim 2
Independent Claim
61 words
A method of locating underground deposits of uranium comprising A. placing underground a dosimeter in the form of a thin layer about 5 to about 18 mg/cm 2 thick which is capable of storing energy from alpha particles: B. activating said dosimeter to cause it to release said stored energy from alpha particles; and C. measuring the amount of energy released.
Claim 3
Dependent Claim
28 words
A method according to claim 1 wherein said unshielded dosimeter is held in a support which directly exposes both sides of said dosimeter to gases from the ground.
Claim 4
Dependent Claim
15 words
A method according to claim 1 wherein said dosimeter is mounted within an inverted cup.
Claim 5
Dependent Claim
24 words
A method according to claim 1 wherein said dosimeter has an area equal to that of a disk at least 6 mm in diameter.
Claim 6
Dependent Claim
17 words
A method according to claim 1 wherein said dosimeter is directly exposed to gases from the ground.
Claim 7
Dependent Claim
31 words
A method according to claim 1 wherein said dosimeter is placed about 24 to about 30 inches underground and is left underground about 2 to about 4 weeks before being activated.
Claim 8
Dependent Claim
21 words
A method according to claim 1 wherein a plurality of said dosimeters are placed about 100 to about 200 feet apart.
Claim 9
Dependent Claim
17 words
A method according to claim 1 wherein said energy is released as light by heating said dosimeter.
Claim 10
Dependent Claim
68 words
A method according to claim 1 wherein two dosimeters are placed underground together, one thin layer unshielded from alpha particles and the other enclosed in a shield which excludes alpha particles but not gamma and beta rays, and said method includes the additional last step of substracting the measurement of the energy released from said shielded dosimeter from the measurement of the energy released from the shielded dosimeter.
Claim 11
Dependent Claim
15 words
A method according to claim 9 wherein said shield is aluminum about 3 mils thick.
Claim 12
Dependent Claim
24 words
A method according to claim 1 wherein said dosimeter consists of a matrix containing about 2 to about 30% by weight of a phosphor.
Claim 13
Dependent Claim
18 words
A method according to claim 11 wherein said matrix contains about 5 to about 15% by weight phosphor.
Claim 14
Dependent Claim
26 words
A method according to claim 11 wherein said matrix is transparent to alpha particles and said released energy, and can withstand a temperature of 300° C.
Claim 15
Dependent Claim
11 words
A method according to claim 13 wherein said matrix is polytetrafluoroethylene.
Claim 16
Dependent Claim
20 words
A method according to claim 11 wherein said phosphor has a fading rate of less than 6% in 6 months.
Claim 17
Dependent Claim
14 words
A method according to claim 15 wherein said phosphor is doped CaSO 4 .
Claim 18
Dependent Claim
18 words
A method according to claim 16 wherein said CaSO 4 is doped with about 1% by weight Dy.
Claim 19
Dependent Claim
69 words
Apparatus for locating underground deposits of uranium comprising pairs of dosimeters each dosimeter being a thin layer about 5 to about 18 mg/cm 2 thick, each dosimeter containing a phosphor which is capable of storing energy from alpha particles, one of said dosimeters in each pair being unshielded from alpha particles and the other being enclosed in a shield which excludes alpha particles but not gamma and beta rays.
Claim 20
Dependent Claim
69 words
Apparatus for locating underground deposits of uranium comprising pairs of dosimeters each dosimeter being a thin layer about 5 to about 18 mg/cm 2 thick, each dosimeter containing a phosphor which is capable of storing energy from alpha particles, one of said dosimeters in each pair being unshielded from alpha particles and the other being enclosed in a shield which excludes alpha particles but not gamma and beta rays.
Claim 21
Dependent Claim
16 words
Apparatus according to claim 18 wherein each pair of dosimeters is mounted within an inverted cup.
Claim 22
Dependent Claim
24 words
An apparatus according to claim 18 wherein said dosimeter has an area equal to that of a disk at least 6 mm in diameter.
Claim 23
Dependent Claim
17 words
An apparatus according to claim 18 wherein said energy is releasable as light by heating said phosphor.
Claim 24
Dependent Claim
15 words
An apparatus according to claim 18 wherein said shield is aluminum about 3 mils thick.
Claim 25
Dependent Claim
28 words
An apparatus according to claim 18 wherein said unshielded dosimeter is held in a support which directly exposes both sides of said dosimeter to gases from the ground.
Claim 26
Dependent Claim
22 words
An apparatus according to claim 18 wherein both dosimeters consist of a matrix containing about 2 to about 30% by weight phosphor.
Claim 27
Dependent Claim
18 words
An apparatus according to claim 24 wherein said matrix contains about 5 to about 15% by weight phosphor.
Claim 28
Dependent Claim
26 words
An apparatus according to claim 24 wherein said matrix is transparent to alpha particles and said released energy, and can withstand a temperature of 300° C.
Claim 29
Dependent Claim
11 words
An apparatus according to claim 26 wherein said matrix is polytetrafluoroethylene.
Claim 30
Dependent Claim
20 words
An apparatus according to claim 18 wherein said phosphor has a fading rate of less than 6% in 6 months.
Claim 31
Dependent Claim
14 words
An apparatus according to claim 28 wherein said phosphor is doped CaSO 4 .
Claim 32
Dependent Claim
18 words
An apparatus according to claim 29 wherein said CaSO 4 is doped with about 1% by weight Dy.
Claim 33
Dependent Claim
44 words
A shielded dosimeter comprising a dosimeter in the form of a thin layer about 5 to about 18 mg/cm 2 thick which is capable of storing energy from alpha particles, enclosed in a shield which excludes alpha particles but not gamma and beta rays.
Claim 34
Dependent Claim
44 words
A shielded dosimeter comprising a dosimeter in the form of a thin layer about 5 to about 18 mg/cm 2 thick which is capable of storing energy from alpha particles, enclosed in a shield which excludes alpha particles but not gamma and beta rays.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |