US4228512A
Expired / Lapsed
US
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Nuclear pulse counting apparatus and technique
Assignee: Dow Chemical Co
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Filing: 1978-05-03
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Granted: 1980-10-14
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Expires: 1998-05-03
Abstract
Abstract A nuclear pulse counting experiment, such as typified by the art of X-ray fluorescence empolys a multichannel analog to digital converter (ADC) which is interfaced with a microprocessor to yield sample/matrix concentration data, as an illustrative example, with a precision which is given by the theoretical nuclear decay statistical limits. In specific regard to X-ray fluorescence analysis, the ADC characterizes each pulse or count according to magnitude without conventional backscatter peak gain stabilization. The data is transferred through a buffer to the microprocessor, which scans the higher energy characterizations for maximum count, identifies that characterization as the peak, ± 1 characterization, and interpolates to develop a refined backscatter peak, stated to at least 1/10 of a characterization, and from which data base all ensuing calculations are predicated.
Inventors
- 👤 John W. Thompson
- 👤 Arthur J. Kamp
- 👤 Edward R. Sederlund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:03
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/22; G01N23/223; G01N2223/00; G01N2223/07; G01N2223/076
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
146 words
In a nuclear pulse counting experiment wherein pulse charges are developed pursuant to a detection step, and converted to amplified voltage pulses proportional to the magnitude of the pulse charges, the method of tabulating such voltage pulses, occurring in a specified energy range, and defining the energy peak center, comprising the steps of: sorting the voltage pulses into at least 128 characterizations according to magnitude, said sorting function being performed essentially without compensation for meandering amplification gain shifts, discontinuing the experiment based on a statistically reliable counting of a numerically sufficient sample of pulse charges, determining that characterization containing the maximum count, ±1 characterization, and defining that characterization as the energy peak center, interpolating to refine the energy peak center to an accuracy of at least 1/10 of a characterization, and tabulating the numerical count of the pulse charges based on the refined energy peak center.
Claim 2
Dependent Claim
146 words
In a nuclear pulse counting experiment wherein pulse charges are developed pursuant to a detection step, and converted to amplified voltage pulses proportional to the magnitude of the pulse charges, the method of tabulating such voltage pulses, occurring in a specified energy range, and defining the energy peak center, comprising the steps of: sorting the voltage pulses into at least 128 characterizations according to magnitude, said sorting function being performed essentially without compensation for meandering amplification gain shifts, discontinuing the experiment based on a statistically reliable counting of a numerically sufficient sample of pulse charges, determining that characterization containing the maximum count, ±1 characterization, and defining that characterization as the energy peak center, interpolating to refine the energy peak center to an accuracy of at least 1/10 of a characterization, and tabulating the numerical count of the pulse charges based on the refined energy peak center.
Claim 3
Dependent Claim
33 words
An X-ray fluorescence analysis performed according to the method of claim 1 to determine sample/matrix quantitative data, wherein the energy peak center of the backscatter is defined according to the mode therein described.
Claim 4
Dependent Claim
34 words
The method of claim 2 wherein the step of terminating data gathering is based on a specified count occurring in any one characterization, and wherein that characterization is defined as the energy peak center.
Claim 5
Dependent Claim
31 words
The method of claim 2 wherein the voltage pulses are sorted into at least 256 characterizations, said experiment being distinguished by a precision expressed by the theoretical nuclear decay statistical limit.
Claim 6
Dependent Claim
20 words
The method of claim 4 including the step of regulating the frequency of the transmission of the characterized voltage pulses.
References Cited (Backward Citations)
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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) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |