Collé Ronald, Laureano-Pérez Lizbeth, Nour Svetlana, La Rosa Jerome J, Zimmerman Brian E, Pibida Leticia, Bergeron Denis E
National Institute of Standards and Technology, Gaithersburg, MD 20899-8462, USA.
J Res Natl Inst Stand Technol. 2017 Dec 27;122:1-19. doi: 10.6028/jres.122.044. eCollection 2017.
A new natural uranium solution standard has been produced and will be disseminated by the National Institute of Standards and Technology (NIST) as Standard Reference Material 4321d. The standard is certified for the massic activities of U, U, and U in solution, and it is based on isotopic mass data for the metallic Certified Reference Material (CRM) 112-A (originally issued as SRM 960) that was obtained from THE U.S. Department of Energy, New Brunswick Laboratory. The metallic CRM was chemically cleaned, dissolved, and gravimetrically diluted to prepare a master solution, which was quantitatively dispensed into 5 mL aliquots that were contained within flame-sealed glass ampoules for each SRM unit. Homogeneity among SRM units, verifying solution homogeneity, was substantiated by photonic-emission integral counting with a NaI(Tl) well counter. Confirmatory measurements were performed by liquid scintillation counting for the total massic activity, and by isotope dilution α spectrometry for the U and U massic activities.
一种新的天然铀溶液标准已制备完成，并将由美国国家标准与技术研究院（NIST）作为标准参考物质4321d发布。该标准对溶液中U、U和U的质量活度进行了认证，它基于从美国能源部新不伦瑞克实验室获得的金属标准参考物质（CRM）112-A（最初作为SRM 960发布）的同位素质量数据。对金属CRM进行化学清洗、溶解并通过重量法稀释以制备母液，然后将母液定量分装到5 mL的等分试样中，每个SRM单元的等分试样都装在火焰密封的玻璃安瓿中。通过使用NaI（Tl）井型计数器进行光子发射积分计数，证实了SRM单元之间的均匀性，验证了溶液的均匀性。通过液体闪烁计数法测量总质量活度，并通过同位素稀释α能谱法测量U和U的质量活度，进行了确证性测量。
