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. 7 figures.
- Inventors:
- Issue Date:
- OSTI Identifier:
- 7274801
- Patent Number(s):
- 5067820
- Application Number:
- PPN: US 7-540240
- Assignee:
- Dept. of Energy, Washington, DC (United States)
- DOE Contract Number:
- AC04-76DP03533
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 19 Jun 1990
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 47 OTHER INSTRUMENTATION; 38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; CALORIMETRY; DATA ACQUISITION; ELECTRONIC CIRCUITS; DESIGN; RADIOACTIVE MATERIALS; OPERATION; TEMPERATURE GRADIENTS; MATERIALS; 440500* - Thermal Instrumentation- (1990-); 400702 - Radiochemistry & Nuclear Chemistry- Properties of Radioactive Materials
Citation Formats
Donohoue, T P, Oertel, C P, Tyree, W H, and Valdez, J L. Radionuclide calorimeter system. United States: N. p., 1991.
Web.
Donohoue, T P, Oertel, C P, Tyree, W H, & Valdez, J L. Radionuclide calorimeter system. United States.
Donohoue, T P, Oertel, C P, Tyree, W H, and Valdez, J L. Tue .
"Radionuclide calorimeter system". United States.
@article{osti_7274801,
title = {Radionuclide calorimeter system},
author = {Donohoue, T P and Oertel, C P and Tyree, W H and Valdez, J 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. 7 figures.},
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}
}