Radionuclide calorimeter system
Abstract
A circuit for measuring temperature differentials in a calorimeter is disclosed. The temperature differential between the reference element and sample element containing a radioactive material is measured via a wheatstone bridge arrangement of thermistors. The bridge is driven with an alternating current on a pulsed basis to maintain the thermal floor of the calorimeter at a low reference value. A lock-in amplifier connected to the bridge phase locks a signal from the bridge to the input pulsed AC signal to provide a DC voltage. The DC voltage is sampled over time and provided to a digital computer. The digital computer, using curve fitting algorithms, will derive a function for the sample data. From the function, an equilibrium value for the temperature may be calculated.
- Inventors:
-
- Denver, CO
- Arvada, CO
- Boulder, CO
- Issue Date:
- Research Org.:
- Rockwell International Corp., Canoga Park, CA (United States)
- OSTI Identifier:
- 868072
- Patent Number(s):
- 5067820
- Application Number:
- 07/540,240
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01K - MEASURING TEMPERATURE
G - PHYSICS G01 - MEASURING G01R - MEASURING ELECTRIC VARIABLES
- DOE Contract Number:
- AC04-76DP03533
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- radionuclide; calorimeter; circuit; measuring; temperature; differentials; disclosed; differential; reference; element; sample; containing; radioactive; material; measured; via; wheatstone; bridge; arrangement; thermistors; driven; alternating; current; pulsed; basis; maintain; thermal; floor; value; lock-in; amplifier; connected; phase; locks; signal; input; provide; dc; voltage; sampled; time; provided; digital; computer; curve; fitting; algorithms; derive; function; data; equilibrium; calculated; curve fitting; measuring temperature; radioactive material; active material; alternating current; dc voltage; temperature differential; input pulse; digital computer; bridge arrangement; wheatstone bridge; amplifier connected; lock-in amplifier; measured via; curve fit; temperature differentials; element containing; /374/422/
Citation Formats
Donohoue, Thomas P, Oertel, Christopher P, Tyree, William H, and Valdez, Joe L. Radionuclide calorimeter system. United States: N. p., 1991.
Web.
Donohoue, Thomas P, Oertel, Christopher P, Tyree, William H, & Valdez, Joe L. Radionuclide calorimeter system. United States.
Donohoue, Thomas P, Oertel, Christopher P, Tyree, William H, and Valdez, Joe L. Tue .
"Radionuclide calorimeter system". United States. https://www.osti.gov/servlets/purl/868072.
@article{osti_868072,
title = {Radionuclide calorimeter system},
author = {Donohoue, Thomas P and Oertel, Christopher P and Tyree, William H and Valdez, Joe L},
abstractNote = {A circuit for measuring temperature differentials in a calorimeter is disclosed. The temperature differential between the reference element and sample element containing a radioactive material is measured via a wheatstone bridge arrangement of thermistors. The bridge is driven with an alternating current on a pulsed basis to maintain the thermal floor of the calorimeter at a low reference value. A lock-in amplifier connected to the bridge phase locks a signal from the bridge to the input pulsed AC signal to provide a DC voltage. The DC voltage is sampled over time and provided to a digital computer. The digital computer, using curve fitting algorithms, will derive a function for the sample data. From the function, an equilibrium value for the temperature may be calculated.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 26 00:00:00 EST 1991},
month = {Tue Nov 26 00:00:00 EST 1991}
}