Standard Test Method for Uranium and Plutonium Concentrations and Isotopic Abundances by Thermal Ionization Mass Spectrometry

Importancia y uso:

5.1 Uranium and plutonium oxides can be used as a nuclear-reactor fuel in the form of pellets. In order to be suitable for use as a nuclear fuel the starting material must meet certain specifications, such as found in Specifications C757, C833, C753, C776, or as specified by the purchaser. The uranium concentration, plutonium concentration, or both, and the isotopic abundances are measured by mass spectrometry following this test method.

5.2 The separated uranium or plutonium element fractions placed on mass spectrometric filaments must be very pure. The quantity required depends upon the sensitivity of the instrument detection system. If an electron multiplier detector is to be used, only a few nanograms of U or Pu are required for isotopic analysis. If a Faraday cup is used, hundreds of nanograms to micrograms of U or Pu are needed. Chemical purity of the sample becomes more important as the sample size decreases, because ion emission of the sample is suppressed by impurities.

Subcomité:

C26.05

Referida por:

C1415-24, E3171-21A, C1636-22, C1411-20, C1832-23, C1816-24, E0321-20, C1672-23, C1128-23, C0698-16, C0697-16

Volúmen:

12.01

Número ICS:

27.120.30 (Fissile materials and nuclear fuel technology)

Palabras clave:

atom percent; isotope dilution mass spectrometry; isotope ratio; mass fraction; thermal ionization mass spectrometry; uranium, plutonium;