【国外标准】 Standard Test Methods for Chemical, Mass Spectrometric, and Spectrochemical Analysis of Nuclear-Grade Plutonium Dioxide Powders and Pellets

4.1 Plutonium dioxide is used in mixtures with uranium dioxide as a nuclear-reactor fuel. In order to be suitable for this purpose, the material must meet certain criteria for plutonium content, isotopic composition, and impurity content. These test methods are designed to show whether or not a given material meets the specifications for these items as described in Specification C757.4.1.1 An assay is performed to determine whether the material has the minimum plutonium content specified on a dry weight basis.4.1.2 Determination of the isotopic content of the plutonium in the plutonium dioxide powder is made to establish whether the effective fissile content is in compliance with the purchaser's specifications.4.1.3 Impurity content is determined to ensure that the maximum concentration limit of certain impurity elements is not exceeded. Determination of impurities is also required for calculation of the equivalent boron content (EBC) as described in Practice C1233.4.2 Fitness for Purpose of Safeguards and Nuclear Safety Applications—Methods intended for use in safeguards and nuclear safety applications shall meet the requirements specified by Guide C1068 for use in such applications.1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade plutonium dioxide powders and pellets to determine compliance with specifications.1.2 The analytical procedures appear in the following order:  SectionsPlutonium Sample Handling   8 to 10Plutonium by Controlled-Potential Coulometry 2Plutonium by Ceric Sulfate Titration 3Plutonium by Amperometric Titration with Iron(II) 2Plutonium by Diode Array Spectrophotometry 3Nitrogen by Distillation Spectrophotometry Using Nessler Reagent  11 to 18Carbon (Total) by Direct Combustion–Thermal Conductivity  19 to 29Total Chlorine and Fluorine by Pyrohydrolysis  30 to 37Sulfur by Distillation Spectrophotometry  38 to 46Plutonium Isotopic Analysis by Mass Spectrometry 4Rare Earth Elements by Spectroscopy  47 to 54Trace Elements by Carrier–Distillation Spectroscopy  55 to 62(Alternative: Impurities by ICP-AES or ICP-MS)  Impurity Elements by Spark-Source Mass Spectrography 63 to 69Moisture by the Coulometric Electrolytic Moisture Analyzer 70 to 77Total Gas in Reactor-Grade Plutonium Dioxide Pellets 5Plutonium-238 Isotopic Abundance by Alpha Spectrometry 3Americium-241 in Plutonium by Gamma-Ray Spectrometry 2Rare Earths By Copper Spark-Spectroscopy 78 to 87Plutonium Isotopic Analysis by Mass Spectrometry 88 to 96Oxygen-To-Metal Atom Ratio by Gravimetry 97 to 1041.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see Sections 6, 16.2.5, 44.7, 51.9 and 92.5.1.