Development of Laser-Based Resonance Ionization Spectroscopy Techniques for 81Kr and 85Kr Measurements in the Geosciences

地球科学中用于 81Kr 和 85Kr 测量的激光共振电离光谱技术的开发

• 批准号: 9410695
• 负责人: Norbert Thonnard
• 金额: $ 40万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-01 至 2000-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9410695&HistoricalAwards=false
• 关键词: Development; Laser; Based; Resonance; Ionization

9410695 Thonnard This award provides funding for the development of a laser-based resonance ionization spectroscopy technique capable of measuring the isotopic abundances of noble gas constituents krypton-81 and krypton-85 in natural samples. The project is to be carried out in the Institute for Rare Isotope Measurements at the University of Tennessee. Accurate measurements of the radionuclei of krypton-81 and krypton-85 can contribute to a better understanding of processes in the environment, including dating of polar ice and very old groundwater, deep ocean circulation rates, and modern water flow patterns. These isotopes have half-lives of 210,000 and 10.8 years respectively and are found in natural samples with isotopic abundances usually less than a part per trillion. Accurate analysis is a problem that has not yet been solved. The PI and colleagues on this project will develop a multi-step technique aimed at achieving an analytical procedure capable of measuring hundreds of environmentally significant samples per year. *** 9405805 Craig This award provides 75% of the funds required for the acquisition of a microscope system for use with transmitted and reflected light to be used in the rare gas isotope laboratory, Scripps Institution of Oceanography at the University of California, San Diego. The University is committed to providing the remaining funds necessary for the acquisition. The microscope system is mainly to be used by researchers working with fluid, glass, and crystalline inclusions trapped in samples of basaltic rocks that have been extruded from the Earth's mantle. The microscope is needed for the location and identification of these small inclusions prior to extraction of the rare gases (argon, helium, and neodymium) for isotopic analysis. The researchers at the Scripps Institution of Oceanography are using the isotopic content of the rare gases brought up from the mantle to understand the geochemical evolution of the mantle. ***

小行星9410695 该奖项提供资金，用于开发一种基于激光的共振电离光谱技术，该技术能够测量天然样品中惰性气体成分氪-81和氪-85的同位素丰度。 该项目将在田纳西大学稀有同位素测量研究所进行。 精确测量氪-81和氪-85的放射性核有助于更好地了解环境中的过程，包括极地冰和非常古老的地下水的年代测定、深海循环速率和现代水流模式。这些同位素的半衰期分别为210，000年和10.8年，在天然样品中发现的同位素丰度通常低于万亿分之一。准确的分析是一个尚未解决的问题。该项目的PI和同事将开发一种多步骤技术，旨在实现每年能够测量数百个环境重要样品的分析方法。 克雷格 该奖项提供了75%的资金，用于购买一个显微镜系统，用于传输和反射光，用于稀有气体同位素实验室，斯克里普斯海洋学研究所在加州，圣地亚哥大学。该大学致力于提供收购所需的剩余资金。 显微镜系统主要用于研究从地幔中挤出的玄武岩样品中捕获的流体，玻璃和结晶包裹体的研究人员。在提取稀有气体（氩、氦和钕）进行同位素分析之前，需要使用显微镜来定位和识别这些小包裹体。斯克里普斯海洋学研究所的研究人员正在利用从地幔中携带的稀有气体的同位素含量来了解地幔的地球化学演化。 地幔 ***