1.1 这种做法是实践的替代方案 C1411 用于在小质量样品（约5μg钚和1mL溶液中高达0.5mg铀）中离子交换分离铀和钚，并将其与其他杂质分离，以便随后通过热电离质谱法（TIMS）进行同位素丰度和含量分析。除了适用于较小的样品尺寸外，这种做法还避免了使用盐酸（HCl）和氢氟酸（HF），并且不需要使用实践中要求的两个阴离子交换柱 C1411 . 1.2 在化学上未分离的样品中，质量为238的等压核素( 238 U和 238 Pu）和质量241( 241 蒲和 241 Am）将一起测量，从而影响钚同位素组成结果的准确性。因此，在同位素分析之前，元素的化学分离至关重要。以下段落中给出的浓度和体积可以根据更大的样品量、不同类型的阴离子交换树脂等进行修改。 1.3 以国际单位制表示的值应被视为标准值。本标准不包括其他计量单位。 1.4 本标准并不旨在解决与其使用相关的所有安全问题（如果有的话）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 =====意义和用途====== 5.1 铀和钚用于核反应堆燃料，必须进行分析，以确保它们符合规范中所述的同位素组成验收标准 C833 和 C1008 标准由制造商和最终用户（或买方和卖方）共同商定。本标准规程用于从化学上分离等压干扰 238 U和 238 蒲和从 241 我和 241 在TIMS进行同位素丰度测定之前。 5.2 在授权使用高氯酸的设施中，试验方法中的分离 C698 可以在同位素丰度测定之前使用。使用TIMS的铀和钚含量以及同位素丰度可以通过使用这种分离实践和以下测试方法来确定 C698 , C1625 ，或 C1672 .

1.1 This practice is an alternative to Practice C1411 for the ion exchange separation in small mass samples (~5 μg of plutonium and up to 0.5 mg of uranium in 1 mL of solution) of uranium and plutonium from each other and from other impurities for subsequent isotopic abundance and content analysis by thermal ionization mass spectrometry (TIMS). In addition to being adapted to smaller sample sizes, this practice also avoids the use of hydrochloric acid (HCl) and hydrofluoric acid (HF) and does not require the use of two anion exchange columns as required in Practice C1411 . 1.2 In chemically unseparated samples isobaric nuclides at mass 238 ( 238 U and 238 Pu), and mass 241 ( 241 Pu and 241 Am) will be measured together thus compromising the accuracy of the results of isotopic composition of Pu. Therefore, chemical separation of elements is essential prior to isotopic analyses. Concentrations and volumes given in the paragraphs below can be modified for larger sample sizes, different types of anion exchange resin, etc. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Uranium and plutonium are used in nuclear reactor fuel and must be analyzed to ensure that they meet acceptance criteria for isotopic composition as described in Specifications C833 and C1008 . The criteria are set by mutual agreement between the manufacturer and end user (or between buyer and seller). This standard practice is used to separate chemically the isobaric interferences from 238 U and 238 Pu and from 241 Am and 241 Pu, and from other impurities prior to isotopic abundance determination by TIMS. 5.2 In facilities where perchloric acid use is authorized, the separation in Test Method C698 may be used prior to isotopic abundance determination. Uranium and plutonium content as well as isotopic abundances using TIMS can be determined by using this separation practice and by following Test Methods C698 , C1625 , or C1672 .