Development of novel sample preparation techniques for analysis of micro-gram quantities of bulk actinides

为了支持核安全、核取证和制造过程控制，需要准确和精确地分析散装鳗系元素材料。该项目的目标是评价微尺度采样和光谱技术在支持核安全方面对鳗系元素材料进行化学分析的性能。减少样品大小是处理放射性材料时的一个关键好处，因为它可以提高安全性和减少废物产生。原则上，聚焦离子束扫描电子显微镜(FIB-SEM)和激光切割可以产生亚微克的铀和钚样品，用于同位素、痕量元素、表面、物相和形态分析。要研究的关键发展是如何在保持正在分析的材料性质的同时，准备用于小规模分析的鳗系元素样品。在这个范围广泛的项目中，学生将通过FIB和激光切割制备样品，并使用先进的质谱学和表面技术(如TIMS、SIMS、LIBS、ESI-MS、LA-ICP-MS、APT、TEM等)进行分析。在学术界和工业界。还将研究这些样品的微尺度溶解和放射化学，并通过非破坏性辐射测量来比较其性能与整体方法。该项目将涉及现代核分析化学中的许多关键领域，确定应用最先进工艺所需的最小样本量，并确定与整体放射化学方法相比较的表面技术分析鳗系元素材料的交叉点。任何发展的结果都将产生具有广泛工业意义的新方法。

The accurate and precise analysis of bulk actinide materials is required in support of nuclear security, nuclear forensics and manufacturing process control. The objective of the project is to evaluate the performance of micro-scale sampling and spectrometry techniques for the chemical analysis of actinide materials in support of nuclear security. Reduced sample size is a key benefit when working with radioactive materials, as it leads to improved safety and reduced waste generation.In principal, focused ion beam scanning electron microscopy (FIB-SEM) and laser cutting can generate sub-microgram samples of uranium and plutonium for isotopic, trace elemental, surface, phase and morphological analysis. The key development to be investigated is how actinide samples can be prepared for analysis on the small scale, whilst retaining the material properties being analysed for. In this wide-ranging project the student will prepare samples by FIB and laser cutting and analyse them by advanced mass spectrometry and surface techniques (e.g. TIMS, SIMS, LIBS, ESI-MS, LA-ICP-MS, APT, TEM etc.) in academia and industry. These samples will also be studied for their micro-scale dissolution and radiochemistry, and by non-destructive radiometry to compare performance to bulk methods. The project will address many of the key areas in modern nuclear analytical chemistry, establishing minimum sample sizes required by applying state-of-the-art processes, and determining the crossover point in the analysis of actinide materials by surface techniques in comparison with bulk radiochemical methods. The outcomes of any developments will yield novel approaches of wide industrial relevance.