Acquisition of a femtosecond laser ablation system

购置飞秒激光烧蚀系统

• 批准号: 0901938
• 负责人: Clark Johnson
• 金额: --
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-15 至 2010-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0901938&HistoricalAwards=false
• 关键词: Acquisition; femtosecond; laser; ablation; system

0901938JohnsonThis proposal seeks funding of $60K for partial purchase of a femtosecond laser ablation system (fsLA) to be used as an sample introduction system on an existing multi-collector ICP-MS system within the Radiogenic Isotope Laboratory at UW-Madison. The University will contribute $355K and NASA will contribute $60K toward the purchase. Isotope measurements may be improved by shorter wavelength, faster pulse-width laser ablation systems. Systems with wavelengths in the deep UV and femtosecond pulse widths are beginning to be fielded in the geoscience community. Recent studies show radiogenic isotopes ratios with elements like Sr, Pb and Hf are better preserved from source material when ablated using fsLA. The prime goal for initial experiments is measuring Fe isotopes in individual carbonates produced by microbial Fe3+ reduction. The fsLA system will be necessary to tease out Fe fractionation factors which would not possible with bulk analyses. Measurements with bulk carbonates is particularly challenging because Fe isotopes tend to fractionate during dissolution. The effect is noticeable when sequential acid digestions are performed. The fsLA system should allow individual carbonates to be analyzed mitigating this bias. The PIs present considerable evidence to support the fsLA system over microprobe or SIMS analyses. Combination analysis with both SIMS and fsLA is suggested. The fsLA system will offer a wide range of analytical possibilities to UW-M. Students and post-docs will be able to utilize the system. While Fe isotopes will be initial focus, sedimentary and igneous geochemistry will benefit from shorter pulse laser ablation. Zircon U-Pb and Hf analyses will be possible. Collaborative efforts with the Rare Gas Laboratory at UW-M will also be evident.***

0901938Johnson此提案寻求资助 6 万美元，用于部分购买飞秒激光烧蚀系统 (fsLA)，该系统将用作威斯康辛大学麦迪逊分校放射性同位素实验室内现有多接收器 ICP-MS 系统的样品引入系统。大学将出资 35.5 万美元，NASA 将出资 6 万美元用于购买。更短波长、更快脉冲宽度的激光烧蚀系统可以改善同位素测量。具有深紫外波长和飞秒脉冲宽度的系统开始在地球科学界投入使用。最近的研究表明，当使用 fsLA 消融时，源材料中 Sr、Pb 和 Hf 等元素的放射性同位素比率可以得到更好的保存。初始实验的主要目标是测量微生物 Fe3+ 还原产生的单个碳酸盐中的 Fe 同位素。 fsLA 系统对于梳理出铁分馏因子是必要的，而这在批量分析中是不可能实现的。散装碳酸盐的测量尤其具有挑战性，因为铁同位素在溶解过程中往往会分馏。当进行连续酸消化时，效果是显而易见的。 fsLA 系统应该允许对单个碳酸盐进行分析，以减轻这种偏差。 PI 提供了大量证据来支持 fsLA 系统优于微探针或 SIMS 分析。建议使用 SIMS 和 fsLA 进行组合分析。 fsLA 系统将为威斯康星大学密歇根大学提供广泛的分析可能性。学生和博士后将能够使用该系统。虽然铁同位素将成为最初的焦点，但沉积和火成岩地球化学将受益于更短的脉冲激光烧蚀。锆石 U-Pb 和 Hf 分析将成为可能。与威斯康辛大学稀有气体实验室的合作也将是显而易见的。***