Delayed neutron method for measurement of fissile/fertile content of samples ranging from environmental to irradiated fuel

Conference · Sun Jul 01 04:00:00 EDT 1984 · Nucl. Mater. Manage.; (United States)

OSTI ID:6318149

Proctor, A E; Akers, D W; Harker, Y D; Mandler, J W

A delayed-neutron assay method is described which is capable of accurately determining the /sup 235/U and /sup 238/U contents of a wide range of materials. The method consists of irradiation in the Coupled Fast Reactivity Measurement Facility (CFRMF) at the Idaho National Engineering Laboratory (INEL), one position in the thermal driver area for /sup 235/U assay, and a fast neutron flux position for /sup 238/U. After irradiation, delayed neutron counting is used to measure the uranium content of the sample. By utilizing fast and thermal neutron irradiation and counting cycles, the samples /sup 238/U and /sup 235/U contents are determined. Minimal sample preparation and handling is required to obtain accurate results. The method has been used successfully on a wide range of samples, including environmental (soil) samples, irradiated and unirradiated fuel, and debris from the Three Mile Island Unit II Reactor core. Measurement precision of up to 0.5% can be achieved; sensitivity for low level samples is 9 counts min/sup -1/ nanogram/sup -1/ for /sup 235/U and 0.02 counts min/sup -1/ nanogram/sup -1/ for /sup 238/U. The fissile and/or fertile contents of samples containing /sup 233/U, /sup 239/Pu, /sup 240/Pu, /sup 237/Np, or /sup 232/Th could be determined by the same method. Data from representative samples are presented to illustrate the usefulness of these techniques.

• Research Organization: EG and G Idaho, Inc., Idaho Falls, Idaho
• OSTI ID: 6318149
• Report Number(s): CONF-840734-
• Conference Information: Journal Name: Nucl. Mater. Manage.; (United States) Journal Volume: 13
• Country of Publication: United States
• Language: English

Related Subjects

055001* -- Nuclear Fuels-- Safeguards
Inspection
& Accountability-- Technical Aspects
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101 -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
ACCURACY
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
CFRMF REACTOR
CHEMICAL ANALYSIS
COUNTING TECHNIQUES
DELAYED NEUTRON ANALYSIS
ENERGY SOURCES
EPITHERMAL REACTORS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
EXPERIMENTAL REACTORS
FAST REACTORS
FERTILE MATERIALS
FISSILE MATERIALS
FISSIONABLE MATERIALS
FUELS
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE RATIO
ISOTOPES
MANAGEMENT
MATERIALS
MINUTES LIVING RADIOISOTOPES
NEPTUNIUM 237
NEPTUNIUM ISOTOPES
NONDESTRUCTIVE ANALYSIS
NUCLEAR FUELS
NUCLEAR MATERIALS MANAGEMENT
NUCLEAR REACTION ANALYSIS
NUCLEI
ODD-EVEN NUCLEI
PLUTONIUM 239
PLUTONIUM 240
PLUTONIUM ISOTOPES
QUANTITATIVE CHEMICAL ANALYSIS
RADIOACTIVE WASTE MANAGEMENT
RADIOISOTOPES
REACTOR MATERIALS
REACTORS
RESEARCH AND TEST REACTORS
SAMPLE PREPARATION
SENSITIVITY
SOILS
SPENT FUELS
THORIUM 232
THORIUM ISOTOPES
URANIUM 233
URANIUM 235
URANIUM 238
URANIUM ISOTOPES
WASTE MANAGEMENT
YEARS LIVING RADIOISOTOPES
ZERO POWER REACTORS