CAREER: A Molecular Level Investigation of Halogenation as a Mechanism of Trace Gas Production and Organic Carbon Transformation at the Surface Ocean

职业：卤化作为表层海洋痕量气体产生和有机碳转化机制的分子水平研究

• 批准号: 2236695
• 负责人: Yina Liu
• 金额: $ 96.59万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2028-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2236695&HistoricalAwards=false
• 关键词: CAREER; Molecular; Level; Investigation; Halogenation

Halogenation occurs when elements such as chlorine and bromine are added to organic compounds in the ocean. This process can produce gases that damage the ozone layer. Halogenation in the ocean is not well understood because most halogen-containing molecules remain unknown. Understanding halogenation in seawater is key because: (1) it may control recovery of the ozone hole as the Montreal Protocol phases out the use of man-made ozone-depleting substances and (2) some halogen-containing molecules can contribute to removing carbon dioxide from the atmosphere. This CAREER research project will develop new analytical and data science tools that can be used to identify halogen-containing molecules in the marine environment. The research also contributes to public health because damage to the ozone layer in the stratosphere is known to increase risks for skin cancer and cataracts. This CAREER research project includes educational activities to improve scientific literacy and to train the next generation of scientists and policymakers. Project activities include: (1) cutting-edge research training for undergraduate and graduate students, (2) partnerships with high school teachers to develop teaching materials, and (3) building relationships with communities underrepresented in STEM by working with established outreach programs led by the Texas Sea Grant Program.The motivation for this NSF CAREER research project is that organic carbon (OC) halogenation simultaneously affects the carbon cycle and atmospheric chemistry, contributing to stratospheric ozone depletion. The overarching research goal of this CAREER project is to identify the molecular-level chemical drivers of volatile and non-volatile halogenated organic carbon (VHOC and HOC) formation in the surface ocean. A series of laboratory experiments, student-led field observations, untargeted analyses using high-resolution mass spectrometry, and novel data pipelines will be used to achieve this goal through the pursuit of four specific research objectives: (1) identify OC moieties susceptible to halogenation, (2) identify VHOC precursor compounds in halogenation and assess production efficiency in single model compounds and complex mixtures, (3) identify HOC precursor compounds, trace HOC products, and predict their stabilities, and (4) determine the natural occurrence and chemical characteristics of HOC in the ocean. These research objectives are integral to the educational objectives. HOC characterization in the ocean will be achieved through annual undergraduate student-led cruises that will expose students to cutting-edge research. High school teachers will be funded in the summer to contribute to laboratory experiments alongside the Principal Investigator (PI) and graduate and undergraduate students. The collaboration between the PI and teachers will be used to develop high school instructional resources and classroom activities for a Marine Organic Biogeochemistry curriculum. Research results from this CAREER research will be synthesized and communicated to underrepresented communities through collaboration with the statewide network of the Texas Sea Grant agents, specialists, and communicators. This project will produce a first-of-its-kind HOC library and time series in the Gulf of Mexico that will provide a solid foundation for future HOC research by the broader scientific community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

当氯和溴等元素添加到海洋中的有机化合物中时，就会发生卤化。这个过程会产生破坏臭氧层的气体。海洋中的卤化作用尚不清楚，因为大多数含卤素分子仍然未知。了解海水中的卤化作用至关重要，因为：(1) 随着《蒙特利尔议定书》逐步淘汰人造臭氧消耗物质的使用，它可以控制臭氧空洞的恢复；(2) 一些含卤素分子有助于去除二氧化碳来自大气层。该职业研究项目将开发新的分析和数据科学工具，可用于识别海洋环境中的含卤素分子。这项研究还对公共健康做出了贡献，因为众所周知，平流层臭氧层的破坏会增加皮肤癌和白内障的风险。该职业研究项目包括旨在提高科学素养和培训下一代科学家和政策制定者的教育活动。项目活动包括：(1) 为本科生和研究生提供前沿研究培训，(2) 与高中教师合作开发教材，以及 (3) 通过与由以下机构领导的既定外展项目合作，与 STEM 中代表性不足的社区建立关系德克萨斯州海洋资助计划。该 NSF 职业研究项目的动机是有机碳 (OC) 卤化同时影响碳循环和大气化学，导致平流层臭氧消耗。该 CAREER 项目的总体研究目标是确定海洋表层挥发性和非挥发性卤化有机碳（VHOC 和 HOC）形成的分子水平化学驱动因素。一系列实验室实验、学生主导的现场观察、使用高分辨率质谱的非针对性分析以及新颖的数据管道将用于通过追求四个具体研究目标来实现这一目标：（1）识别易受卤化影响的OC部分，(2) 识别卤化中的 VHOC 前体化合物并评估单一模型化合物和复杂混合物的生产效率，(3) 识别 HOC 前体化合物，追踪 HOC 产物并预测其稳定性，以及 (4) 确定自然存在和化学特征的HOC在海洋中。这些研究目标是教育目标的组成部分。海洋中的 HOC 表征将通过年度本科生主导的巡游来实现，这将使学生接触到前沿研究。高中教师将在夏季获得资助，与首席研究员 (PI) 以及研究生和本科生一起为实验室实验做出贡献。 PI 和教师之间的合作将用于开发海洋有机生物地球化学课程的高中教学资源和课堂活动。这项职业研究的研究结果将通过与德克萨斯州海洋补助金代理、专家和传播者的全州网络合作进行综合并传达给代表性不足的社区。该项目将在墨西哥湾建立首个 HOC 库和时间序列，为更广泛的科学界未来的 HOC 研究提供坚实的基础。该奖项反映了 NSF 的法定使命，并被认为是值得的通过使用基金会的智力优势和更广泛的影响审查标准进行评估来提供支持。