Operation of a National Ocean Sciences Accelerator Mass Spectrometry Facility at the Woods Hole Oceanographic Institution

伍兹霍尔海洋研究所国家海洋科学加速器质谱设施的运行

• 批准号: 0228996
• 负责人: William Jenkins
• 金额: $ 623.16万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Cooperative Agreement
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2009-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0228996&HistoricalAwards=false
• 关键词: Operation; National; Ocean; Sciences; Accelerator

0228996Hayes This 5-year cooperative agreement award to Woods Hole Oceanographic Institution in Massachusetts provides support for continued operation of the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. NOSAMS provides analyses of 14C at natural abundance levels. Such data are essential for radiocarbon dating, for studies of dynamic geophysical processes in earth's surface environment (for example, the circulation of the oceans), and for studies of the biogeochemical cycling of carbon. The facility accepts samples from all qualified laboratories and charges fees that vary according to the difficulty of the analysis and the nature of the project. During the four years ending 31 March 2002, the facility completed more than 18,000 analyses and recovered more than 56% of its operating costs from user fees. The facility provides both sample-preparation services and quantitative analyses of 14C. Graphite suitable for mass spectrometric analysis is prepared from samples of carbonate minerals, organic carbon, or inorganic carbon dissolved in water. Quantitative analyses are obtained using a mass spectrometer system for which the minimum sample size is 25 micrograms of C. Attainment of full precision (+/- 3.5 parts per thousand for the 14C /12C ratio) requires a sample size of at least 500 micrograms C. During the five-year period of the cooperative agreement, the capabilities of the facility will be enhanced. A gas-accepting ion source will be installed in order to allow analyses of 14C in a continuously flowing stream of carrier gas. This development will provide tens of low-precision analyses per hour for samples as small as 0.1 micrograms C and will be uniquely applicable to surveys and to monitoring of highly diluted radiocarbon tracers. Procedures for treatment of sediments and other samples containing organic carbon will be automated. The capacity of the sample-preparation laboratory to respond to surges of sample submissions and thus to minimize increases in turnaround time will be increased. Components of the mass spectrometer itself will be rebuilt in order to improve and to stabilize performance. As these improvements are made, the facility will continue to serve the ocean sciences research community, promptly providing radiocarbon analyses as needed each year.***

0228996Hayes 与马萨诸塞州伍兹霍尔海洋研究所签订的为期 5 年的合作协议为国家海洋科学加速器质谱 (NOSAMS) 设施的持续运行提供支持。 NOSAMS 提供自然丰度水平的 14C 分析。 这些数据对于放射性碳测年、地球表面环境动态地球物理过程（例如海洋环流）的研究以及碳的生物地球化学循环的研究至关重要。 该设施接受来自所有合格实验室的样品，并根据分析的难度和项目的性质收取不同的费用。 在截至 2002 年 3 月 31 日的四年里，该机构完成了 18,000 多次分析，并从用户费用中收回了超过 56% 的运营成本。 该设施提供样品制备服务和 14C 定量分析。 适用于质谱分析的石墨由溶解在水中的碳酸盐矿物、有机碳或无机碳样品制备。 使用质谱仪系统进行定量分析，最小样品量为 25 微克 C。要达到完全精度（14C / 12C 比率为+/- 3.5 ppm），需要至少 500 微克 C 的样品量在合作协议的五年期间，该设施的能力将得到增强。 将安装气体接受离子源，以便在连续流动的载气流中分析 14C。 这项开发每小时可对小至 0.1 微克 C 的样品进行数十次低精度分析，并且特别适用于调查和高度稀释的放射性碳示踪剂的监测。沉积物和其他含有机碳样品的处理程序将实现自动化。 样品制备实验室应对样品提交激增的能力将得到提高，从而最大限度地减少周转时间的增加。 质谱仪本身的组件将被重建，以提高和稳定性能。 随着这些改进的完成，该设施将继续为海洋科学研究界服务，每年根据需要及时提供放射性碳分析。***