铀钚单粒子分析技术进展及其在核保障中的应用

Progress and Application of Mass Spectrometry Techniques for Single Particle Analysis in Nuclear Safeguard

  • 摘要: 《核不扩散条约》是奠定当今国际秩序的基本条约之一。为确保各国严格履约,国际社会逐渐形成了一套完善的核保障监督体系。该体系最主要的技术途径是对含铀的单粒子进行化学分析,进而评判涉核活动及设施的性质。其中,能够得到同位素信息这一最关键特征的质谱技术无疑是最核心的。近年来,用于单粒子分析的质谱方法取得了显著进展,其技术极限得到进步。本文综述了用于核保障领域单粒子的化学组成、微观形态、同位素及年龄分析技术的原理、进展及其应用实践,重点总结了各同位素分析技术的主要特征、难点及其局限性,并展望了该领域待解决的技术问题和发展方向。

     

    Abstract: The nuclear Non-proliferation Treaty (NPT) is one of the cornerstones regulating the international order. To make sure that all the member states fulfill their obligation under the treaty, the International Atomic Energy Agency (IAEA) has constructed a rather sound technological management system, i.e. the nuclear safeguard system. Single particle analysis in wipe samples inside and around nuclear facilities is the main focus of nuclear safeguard and application. The chemical fingerprint information, including 235U abundance, 236U abundance, plutonium content and isotope abundance, fluorine content, chemical composition and form of single particles containing radionuclides (mainly uranium and plutonium) in the micron scale, can reveal the source of materials, processing history, potential use, etc., and then reflect the type of nuclear activities in nuclear facilities, which is of great significance for dealing with the threat of nuclear smuggling and nuclear terrorism to prevent nuclear proliferation. As a powerful technique to analyze the isotopic abundance and ratio of radionuclides, mass spectrometry (MS) is no doubt the core technique in nuclear safeguard. In recent years, the MS technique utilized for single particle analysis has been promoted remarkably. In this review, the principle, technical process, and applications of analytical techniques for chemical compositions, micro morphology, isotope and age analysis of single particle analysis in nuclear safeguards were summarized. Some techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission X-ray microscopy (STXM), micro X-ray rluorescence (MXRF), micro-Raman spectroscopy (MRS), were exploited for studying the chemical composition and morphology of uranium/plutonium-containing single particles. Development and application of techniques for the isotope abundance analysis in uranium or plutonium-contaning single particles, such as secondary ion mass spectrometry (SIMS), thermal ionization mass spectrometry (TIMS), multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), microextraction mass spectrometry (microextraction-MS), were also introduced. The main characteristics, difficulties and limitations of various isotope analysis techniques were emphatically discussed, the unsolved problems and future directions were also prospected.

     

/

返回文章
返回