A Miniature Monitor for Time-Resolved Airborne Particle Chemistry

项目概述/摘要：将开发一种微型“生长管收集器”，用于将多个连续的空气中颗粒样品直接集中收集到“收集晶片”上。该仪器将单个颗粒封装在微米直径的水滴中，这些水滴是通过撞击收集的。这种缩聚放大是通过为我们的水基冷凝颗粒计数器开发的一种新技术实现的，通过这种技术，小到几纳米的颗粒在热扩散层流中被放大到几微米的大小。一旦扩大，颗粒很容易通过惯性方式收集到“晶片”上。连续的样品将在同一晶片上收集，以提供时间分辨率。收集晶圆将量身定制，易于与芯片上的实验室或标准离子色谱方法接口，以最小的样品处理允许具有成本效益的化学分析。这种方法将允许在家庭、学校、公共汽车、办公室、工业工作场所以及作为个人监视器对空气中的细颗粒进行时间分辨的化学表征。项目说明：空气中的微小颗粒与不利的健康影响、能见度下降和气候变化有关。提出了一种微型，具有成本效益的收集器，用于确定这些颗粒中发现的主要化学成分的小时浓度。

DESCRIPTION (provided by applicant): Project Summary/Abstract: A miniature "growth tube collector" will be developed to provide the concentrated collection of multiple, sequential airborne particle samples directly onto a "collection wafer". This instrument will encapsulate individual particles within micrometer-diameter water droplets that are collected by impaction. This condensational enlargement is achieved using a new technology developed for our water-based condensation particle counters whereby particles as small as a few nanometers are enlarged to a size of several micrometers in a thermally diffusive, laminar flow. Once enlarged, the particles are readily collected onto the "wafer" by inertial means. Sequential samples will be collected on the same wafer to provide time resolution. The collection wafer will be tailored to readily interface with laboratory-on-a-chip or standard ion chromatography methods to permit cost-effective chemical analysis with minimal sample handling. This approach will permit time-resolved chemical characterization of airborne fine particles in homes, schools, buses, offices, industrial work places and as a personal monitor. Project Narrative: Small, airborne particles are associated with adverse health effects, with visibility degradation, and climate change. Proposed is a miniature, cost-effective collector for determining hourly concentrations of the major chemical constituents found in these particles.