Absorbed dose water calorimeter
An absorbed dose water calorimeter that takes advantage of the low thermal diffusivity of water and the water-imperviousness of polyethylene film. An ultra-small bead thermistor is sandwiched between two thin polyethylene films stretched between insulative supports in a water bath. The polyethylene films insulate the thermistor and its leads, the leads being run out from between the films in insulated sleeving and then to junctions to form a wheatstone bridge circuit. Convection barriers may be provided to reduce the effects of convection from the point of measurement. Controlled heating of different levels in the water bath is accomplished by electrical heater circuits provided for controlling temperature drift and providing adiabatic operation of the calorimeter. The absorbed dose is determined from the known specific heat of water and the measured temperature change.
- Assignee:
- EDB-82-084946
- Patent Number(s):
- US 4312224
- OSTI ID:
- 5676232
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CALORIMETERS
CALORIMETRIC DOSEMETERS
CONTROL
CONVECTION
DESIGN
DOSEMETERS
DOSES
HYDROGEN COMPOUNDS
MEASURING INSTRUMENTS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POLYETHYLENES
POLYMERS
POLYOLEFINS
RADIATION DOSES
SEMICONDUCTOR DEVICES
SPECIFIC HEAT
TEMPERATURE CONTROL
TEMPERATURE MEASUREMENT
THERMISTORS
THERMODYNAMIC PROPERTIES
WATER