MRI: Development of an instrument for quantitative characterization of size distribution of aquatic colloids

胶体是海洋和其他水生环境中最丰富的颗粒，在这些生态系统的结构和功能中起着至关重要的作用。PI申请资金用于设计和制造一种新仪器，水生胶体分析仪（ACAN），用于定量测定水悬浮液中不均匀胶体组合（包括纳米颗粒）的浓度和大小分布。目前还没有仪器可以提供关于水生胶体的多分散系统在大约10纳米到1微米的广泛尺寸范围内的尺寸分布的准确信息。ACAN将利用纳米颗粒跟踪分析（NTA）方法，该方法基于布朗运动和胶体光散射的物理原理。对未扰动样品的ACAN测量将提供一种能力，可以获得关于自然发生的水生胶体多分散组合的前所未有的科学新信息和有价值的信息，这些信息是使用现有技术无法获得的。来自这些测量的数据将是扩展对海洋生物地球化学、碳循环、用于生物地球化学和气候研究的海洋卫星遥感、微生物在海洋生态系统中的作用、大气胶体颗粒及其在海洋中的沉积（通过雨水分析）的理解的基础。更广泛的影响：拟议的仪器有可能影响与粒子动力学相关的广泛环境研究，如生物学、化学、光学、物理学和气候科学。这些测量对于水生科学的许多领域都是至关重要的。该项目将与UCSD普鲁斯学校和斯克里普斯伯奇水族馆的教育和推广项目相结合，这些项目是为K-12学生、大学生和普通公众设计的。

Colloids are the most abundant particles in the ocean and other aquatic environments, and play a crucial role in the structure and functioning of these ecosystems. The PI's request funding to design and fabricate a new instrument, an Aquatic Colloidal Analyzer (ACAN), for quantitative determinations of concentration and size distribution of heterogeneous colloidal assemblages (including nanoparticles) present in aqueous suspensions. No instrumentation is presently available which provides accurate information about size distribution of polydisperse systems of aquatic colloids over a broad size range from about 10 nm to 1 µm. The ACAN will utilize a Nanoparticle Tracking Analysis (NTA) method, which is based on physical principles of Brownian motion and light scattering by colloids. The ACAN measurements on unperturbed samples will provide a capability for acquiring an unprecedented wealth of scientifically new and valuable information on polydisperse assemblages of naturally occurring aquatic colloids, which cannot be obtained using present techniques. The data from these measurements will be fundamental in extending the understanding of the biogeochemistry of the ocean, the carbon cycle, satellite remote sensing of the oceans for biogeochemical and climate studies, the roles of microbes in ocean ecosystems, and atmospheric colloidal particles and their deposition into the ocean (via rainwater analysis).Broader Impacts: The proposed instrument has the potential to impact a broad range of environmental studies related to particle dynamics, such as biology, chemistry, optics, physics and climate science. These measurement are critical for many fields in the aquatic sciences The project would interface with the education and outreach projects with the UCSD Preuss School and the Scripps Birch Aquarium designed for K-12 students, college students, and general public.