Radionuclide calorimeter system

Patent · Tue Nov 26 04:00:00 EST 1991

OSTI ID:7274801

Donohoue, T P; Oertel, C P; Tyree, W H; Valdez, J L

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.

• DOE Contract Number: AC04-76DP03533
• Assignee: Dept. of Energy, Washington, DC (United States)
• Patent Number(s): US 5067820; A
• Application Number: PPN: US 7-540240
• OSTI ID: 7274801
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400702 -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
440500* -- Thermal Instrumentation-- (1990-)
47 OTHER INSTRUMENTATION
CALORIMETRY
DATA ACQUISITION
DESIGN
ELECTRONIC CIRCUITS
MATERIALS
OPERATION
RADIOACTIVE MATERIALS
TEMPERATURE GRADIENTS