Developement of Tandem, Double-focusing, Electron Impact, Gas Source Mass Spectrometer for Measurement of Isotopologues in Geochemistry

地球化学同位素体测量串联双聚焦电子轰击气源质谱仪的研制

• 批准号: 0948938
• 负责人: Edward Young
• 金额: $ 50万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0948938&HistoricalAwards=false
• 关键词: Developement; Tandem; Double; focusing; Electron

This instrument development project will design and build a tandem, double-focusing, high-resolution, high-sensitivity, electron impact, gas source, mass spectrometer. The purpose of the instrument is to analyze rare, doubly-substituted isotopologues of gases occurring in volcanic plumes, geothermal hot springs, hydrocarbon reservoirs, deep crustal microbial communities, gas hydrates, soils, and Earth's atmosphere. The list of gases to be investigated with the proposed instrument includes N2 (15N15N), O2 (17O18O, 18O18O), CH4, N2O, SO2, and OCS but is not limited to them exclusively. The investigation of clumped isotope isotopologue distributions in naturally occurring samples confers the advantage of deriving information on temperature of synthesis of gas species from the measurement of a single phase. It is possible that kinetic isotope fractionation effects accompanying synthesis reactions may provide data on the prevalence of specific reaction mechanisms. An extensive program of experimental calibration will be required to assess both the geothermometric potential and kinetic isotope effects of clumped isotopologues with the new instrument. The expected outcome of use of the proposed instrument is to acquire a deeper understanding of present-day atmosphere-hydrosphere-lithosphere interactions. The improved knowledge of the modern world will then be used to develop calibrated interpretations of ancient atmospheric proxies in the geologic record. The ultimate goal is to understand the chemical evolution of Earth's atmosphere with as great a time resolution as permitted by available samples such as polar ice cores or rock strata. The use of a new mass spectrometer of unprecedented capability is likely to give rise to applications that cannot be predicted. In the context of broader impact on human society, the study of trace greenhouse gases such as CH4 and N2O will contribute to evaluating global warming and climate change.

本仪器研制项目将设计并建造一台串联、双聚焦、高分辨率、高灵敏度、电子轰击、气体源、质谱仪。该仪器的目的是分析火山羽流、地热温泉、碳氢化合物储层、地壳深部微生物群落、天然气水合物、土壤和地球大气中出现的气体的稀有双取代同位素。 拟用仪器研究的气体清单包括N2（15 N15 N）、O2（17 O 18 O、18 O 18 O）、CH 4、N2 O、SO2和OCS，但不限于这些气体。 在天然存在的样品中的聚集的同位素同位素体分布的调查赋予从单相的测量导出关于气体物质的合成的温度的信息的优点。 伴随合成反应的动力学同位素分馏效应可能提供关于特定反应机制的流行的数据。将需要一个广泛的实验校准计划，以评估地质温度的潜力和动力学同位素效应的聚集同位素与新的仪器。使用拟议的仪器的预期成果是更深入地了解当今大气圈-水圈-岩石圈的相互作用。 对现代世界的进一步了解将用于对地质记录中的古代大气代用指标进行校准解释。 最终的目标是了解地球大气层的化学演化，并在极地冰芯或岩层等现有样本的允许范围内获得尽可能高的时间分辨率。 使用一种具有前所未有能力的新质谱仪可能会产生无法预测的应用。 在对人类社会产生更广泛影响的背景下，对甲烷和氧化亚氮等微量温室气体的研究将有助于评估全球变暖和气候变化。