Abstract This study presents a new approach to filament modification by laser ablation for analysis of femtograms of plutonium (Pu) by thermal ionization mass spectrometry (TIMS). This method simplifies the often rigorous and labor-intensive sample loading necessary for low-level analyses by TIMS with solution-loaded laser ablation modified sources (SLLAMS). By applying a Parafilm™ coating to the surface of the filament and then ablating through the film to reveal metal beneath, a point source is created at the optical center of the filament. A solution containing ppt-levels of Pu can then be applied over the ablated region, dried slowly into the crater, and then carburized. All analyses were made by multiple ion counting system on a Nu Instruments TIMS. We report uncertainties of 10% 2σ for 240Pu/239Pu of CRM-137 samples totaling 5 – 7 femtograms (fg; 1E-15 g) with an average sample utilization efficiency of 1.3%.

中文翻译：

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用于热电离质谱的溶液加载激光烧蚀修正源 (SLLAMS) 增强 Pu 发射

摘要 本研究提出了一种新的激光烧蚀灯丝改性方法，用于通过热电离质谱 (TIMS) 分析飞克级的钚 (Pu)。这种方法简化了 TIMS 使用溶液加载激光烧蚀修改源 (SLLAMS) 进行低级分析所需的通常严格且劳动密集型的样品加载。通过在灯丝表面涂上一层 Parafilm™ 涂层，然后通过薄膜烧蚀露出下面的金属，在灯丝的光学中心产生一个点光源。然后可以将含有 ppt 级 Pu 的溶液涂在烧蚀区域上，慢慢干燥到凹坑中，然后进行渗碳。所有分析均通过 Nu Instruments TIMS 上的多离子计数系统进行。