Measurement of Surfactants on Wavy Water Surfaces Using Vibrational Sum-Frequency Spectroscopy

天然存在的表面活性剂存在于大部分海洋的表面。这些物质对海洋和大气之间的气体交换具有关键影响，并可能构成来自海洋的大部分有机物质，形成有机大气气溶胶。研究这些物质的浓度和动力学一直很困难，因为没有一种非侵入性的方法来测量它们而不改变环境波和湍流特性，这与表面活性剂浓度密切相关。EAGER项目将开发一种新的方法，并证明其在波浪水面上的可行性，如果仪器能够充分硬化，这将使实验室和海洋中的许多有趣的研究成为可能。本研究的目的是证明，振动和频光谱（VSFS）可以作为一种非侵入性的原位方法，直接测量表面活性剂浓度的风粗糙的水面。这项研究将使用合成射流阵列坦克（SJAT）在华盛顿大学。表面活性剂浓度将使用振动和频光谱的非线性激光光谱法原位测量。SJAT是一个独特的设施，作为先前NSF赞助的工作的一部分。这项研究将提供一种新的方法来测量空气-水界面上的表面活性剂。如果成功的话，VSFS将提供对表面活性物质影响空气-水气体传输过程并被输送到大气中形成有机气溶胶的机制的详细了解。PI在这一领域有着广泛的重大贡献记录。实验室的实验是必不可少的长期目标的发展VSFS方法，可用于在现场海洋测量天然存在的surfactors.Broader影响：该项目将促进教学，培训和学习，通过参与安排通过华盛顿空间赠款夏季本科生研究计划（SURP）的暑期本科生研究实习生。 该项目将通过以下方式加强研究和教育基础设施：1.开发一个关于空气-水交换过程的实践演示，该演示将每年在太平洋科学中心主办的科学博览会上展示。继续以问答形式举办研讨会，讨论海洋在全球气候变化中的作用，重点是海气交换过程，为8 - 12年级的20 - 30名学生提供小组（与观众的复杂程度相匹配）3.继续参加华盛顿大学的"数学日"在华盛顿州的高中开展推广计划，每年为大约120名学生和高中教师举办关于海洋学中数学应用的讲座。为感兴趣的学校和班级开发合成射流阵列坦克设施的标准参观和演示2。通过美国宇航局赞助的华盛顿太空补助金SURP，从有色人种学生人数较多的地方社区大学招募暑期研究实习生

Naturally occurring surfactants are found at the surface of much of the ocean. These substances have a critical impact on the exchange of gases between the ocean and the atmosphere and may compose the bulk of the organic mass coming from the ocean to form organic atmospheric aerosols. It has been difficult to study the concentration and dynamics of these substances because there is not a noninvasive method to measure them without altering the ambient wave and turbulence characteristics, which are intricately linked with the surfactant concentration. This EAGER project will develop a new method and demonstrate its feasibility for wavy water surfaces, which should enable many interesting studies both in the laboratory, and in the ocean if the instrument can be sufficiently hardened. The objective of this research is to demonstrate that vibrational sum-frequency spectroscopy (VSFS) can be used as a non-invasive in situ method for direct measurement of surfactant concentrations on wind-roughened water surfaces. This research will use the synthetic jet array tank (SJAT) at the University of Washington. Surfactant concentrations will be measured in situ using the nonlinear laser spectroscopic method of vibrational sum-frequency spectroscopy. The SJAT is a unique facility constructed as part of prior NSF-sponsored work.The study will provide a novel approach to measurement of surfactants on air-water interfaces. If successful, VSFS will provide detailed understanding on the mechanisms by which surface active material affect air-water gas transfer processes and are transported to the atmosphere to form organic aerosols. The PI has an extensive record of significant contributions in this area. The laboratory experiments are essential for progress towards the long-term goal of developing a VSFS methodology that could be used for in situ oceanographic measurements of naturally occurring surfactants.Broader Impacts :The project will promote teaching, training, and learning through participation of a summer undergraduate research intern arranged through the Washington Space Grant Summer Undergraduate Research Program (SURP). The project will enhance infrastructure for research and education by:1. Developing a hands-on demonstration on air-water exchange processes that will be presented yearly at the Science Expo sponsored by the Pacific Science Center 2. Continuing to present a seminar in a question and answer discussion format dealing with the role of the oceans in global climate change, with emphasis on air-sea exchange processes, presented to groups of 20-30 students for grades 8-12 (with level of sophistication matched to the audience)3.Continuing to participate in the University of Washington's "Math Day" outreach program for high schools in Washington State by presenting lectures on the use of mathematics in oceanography to approximately 120 students and high school teachers per yearThe project will broaden the participation of underrepresented groups by:1. Developing a standard tour and demonstration of the synthetic jet array tank facility including for interested schools and classes2. Recruiting summer research interns from local community colleges with high populations of students of color through the NASA-sponsored Washington Space Grant SURP