Development and Deployment of Isotopic Dilution Methods for Determining Atmospheric Dimethyl Sulfide and Dimethyl Sulfone

PI计划开发气态二甲基亚砜(DMSO)和二甲基砜(DMSO2)的分析方法，并在附近的沿海地点进行探索性测量。他的目标是(1)使用同位素稀释来提高精密度，避免由于捕集器中的反应以及采样和分析效率的差异而产生的问题，(2)用超临界流体二氧化碳解吸，以简化提取过程，从而实现自动化，(3)使用四极质谱计作为检测器，将3分钟样品的检测下限提高到0.3PPTV；(4)通过直接向歧管中添加零空气来评估多种本底水平。

The PI plans to develop analytical methods for gaseous dimethylsulfoxide (DMSO) and dimethylsulfone (DMSO2) and to conduct exploratory measurements at a nearby coastal site. His objectives are to (1) use isotopic dilution to improve precision and circumvent problems due to reactions in the trap and variability in sampling and analysis efficiencies, (2) desorb with supercritical fluid carbon dioxide to simplify the extraction process thus allowing automation, (3) improve detection limits to 0.3 pptv for 3 minute samples using a quadrupole mass spectrometer as a detector, and (4) evaluate manifold background levels by adding zero air directly to the manifold.