MRI: Acquisition of Light Stable Isotope Mass Spectrometers for Research and Teaching in Geochemistry, Paleobiology, and Cosmochemistry

MRI：购买光稳定同位素质谱仪用于地球化学、古生物学和宇宙化学的研究和教学

• 批准号: 0923831
• 负责人: Albert Colman
• 金额: $ 46.32万
• 依托单位: University of Chicago
• 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: 2009-09-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0923831&HistoricalAwards=false
• 关键词: MRI; Acquisition; Light; Stable; Isotope

0923831Colman "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." This proposal seeks funding for acquisition of two light stable isotope mass spectrometers. These instruments will be incorporated into the newly renovated stable isotope geochemistry lab at the University of Chicago. The "newest" IRMS currently in the facility is a 20 year old Delta E which cannot be fitted for continuous flow operation. The proposal seeks a Thermo Delta V Plus IRMS configured for continuous flow with various introduction interfaces (EA, TCEA, GasBench II). This will allow determination of bulk H, C, N, O and S isotopes. Additionally, a MAT 253 IRMS for carbon dioxide, carbon monoxide, and sulfur isotopologue studies is requested. The IRMS will be used to understand the marine phosphorous cycle and biogeochemistry. The inorganic phosphorous oxygen isotope composition differs among riverine, estuarine and marine systems. Isotopic measurements will be used to track P cycling in freshwaters and coastal systems. Pi cycling by bacteria and archaea will be inferred from disequilibrium measurements. Isotopic disequilibria will be measured in oceanic profiles to better understand OM turnover. These measurements require the TCEA with reverse-flow configuration. Sulfur isopotologues will be used to understand non-mass-dependent photochemical and paleo- (atmospheric) sulfur cycling. Experiments will be conducted with sulfur dioxide under a range of uv irradiation in oxygen/ozone-free atmospheres. Complementary oxygen isotopes measurements will be made in order to tighten constraints on oxygen partial pressures in the Archean atmosphere. Strain across the Tibetan plateau will be analyzed in terms of crustal subduction, crustal thickening, mantle lithosphere removal, and elevation. Light stable isotope paleoaltimetry will be the analytical method ? using the strong fractionation effects seen in oxygen and hydrogen in orographic precipitation. Clumped isotope thermometry will be used to refine paleotemperature estimates to within ±2 °C. IRMS analysis will be used to elucidate sponge metabolism and its impact on nutrient cycling in nutrient-poor reef systems. Diagnostic gene transcripts have recently been identified in sponge symbionts implicating nitrogen fixation in associated bacteria. CO metabolism was likely significant in early Earth?s history. The PI and collaborators will study carbon isotopic fractionation during anaerobic carboxydotrophic microbial growth. A modified injection loop system will be developed allowing smaller sample size(s) and ultimately increased precision. The PI intends to perform calculations relating minor carbon and oxygen isotopologues to infer CO temperature formation. The instruments will be incorporated into the existing UC isotope laboratory and will support multiple departments. The acquisition will represent the only isotopologue measurement capability in the Midwest (and offer inter-calibration possibilities). Stable isotopes will be used in four new or revised courses at the undergraduate and graduate level. The laboratory will also support a mentorship program to train high school teachers from disadvantaged areas of South Chicago. Isotope measurements will be incorporated into four new or revised courses. There are over 70 graduate students and ~70 post-docs who would also benefit. The PI will be responsible for the overall operation and maintenance of both acquired IRMS systems. A full-time technician will be hired to manage day-to-day laboratory use and cost recovery. Remuneration will be used to cover remaining salary and consumables. Space is available to house the new IRMS systems including proper power, temperature, chilling and humidity requirements. Fluorination and vacuum lines are available. Sample prioritization will be transparent and published for outside users. This grant will thus lead to a new hire position at the University of Chicago in addition to equipment purchase.***

0923831Colman “该奖项由 2009 年美国复苏和再投资法案（公法 111-5）资助。”该提案寻求资助购买两台光稳定同位素质谱仪，这些仪器将纳入新装修的稳定同位素地球化学中。芝加哥大学实验室目前该设施中的“最新”IRMS 是一台已有 20 年历史的 Delta E，无法安装。该提案寻求配备各种引入接口（EA、TCEA、GasBench II）的 Thermo Delta V Plus IRMS，这将允许测定大量 H、C、N、O 和 S 同位素。需要用于二氧化碳、一氧化碳和硫同位素体研究的 MAT 253 IRMS。IRMS 将用于了解海洋磷循环和生物地球化学。河流、河口和海洋系统中的无机磷氧同位素组成不同，将用于跟踪淡水和沿海系统中的磷循环，并将通过海洋剖面中的同位素不平衡测量来推断磷循环。为了更好地了解 OM 周转率，这些测量需要使用具有逆流配置的 TCEA。将在无氧/臭氧大气中在一系列紫外线照射下进行非质量依赖的光化学和古（大气）硫循环实验，以加强对氧的限制。青藏高原太古宙大气的分压将从地壳俯冲、地壳增厚、地幔岩石圈去除和地壳俯冲等方面进行分析。光稳定同位素古高度测量将使用在地形降水中观察到的强分馏效应，将使用团块同位素测温法将古温度估计精确到±2°C之内。海绵代谢及其对营养贫乏的珊瑚礁系统中营养循环的影响最近在海绵共生体中发现了诊断基因转录物，这表明相关的固氮作用。二氧化碳代谢在地球早期历史中可能具有重要意义，PI 和合作者将研究厌氧一氧化碳微生物生长过程中的碳同位素分馏。进行与少量碳和氧同位素同位素相关的计算，以推断二氧化碳的形成温度。这些仪器将纳入现有的 UC 同位素实验室，并将支持多个部门。中西部的同位素测量能力（并提供相互校准的可能性）将用于本科生和研究生的四门新课程或修订课程，该实验室还将支持一项指导计划，以培训来自贫困地区的高中教师。南芝加哥同位素测量将纳入四门新课程或修订课程中，70 多名研究生和约 70 名博士后也将受益于所收购的 IRMS 的整体运营和维护。将聘请一名全职技术人员来管理实验室的日常使用和成本回收，并将用于支付剩余工资和消耗品的空间，包括适当的电源、温度和冷却系统。氟化和真空管线的样品优先顺序将是透明的，并会向外部用户公布。因此，除了设备购买之外，这项拨款还将在芝加哥大学带来新的聘用职位。***