Development of an ultrafine aerosol particle mobility analyzer with separation and sensitivity enhancement and real-time monitoring

开发分离、灵敏度增强、实时监测的超细气溶胶颗粒迁移率分析仪

• 批准号: 2105929
• 负责人: Carlos Larriba Andaluz
• 金额: $ 30.33万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-15 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2105929&HistoricalAwards=false
• 关键词: Development; ultrafine; aerosol; particle; mobility

The goal of this project is to develop a new instrument to measure accurately the size distribution of nanoparticles sampled in a variety of environmental applications. The new instrument will enhance the sensitivity, selectivity, and detection speed of ultrafine particles up to 100 nanometers in size, which are referred to as PM0.1 particles. Particles of this small size arise from the same natural or human-made sources that produce larger particles, but PM0.1 particles may pose special health threats because they readily enter the body. Improved measurement techniques could help with the detection and control of PM0.1 particles in the environment. The instrument that will be developed is an Ion Mobility Spectrometer (IMS). The IMS will use an electric field that varies spatially to restrict diffusion of particles in the gas phase and therefore will enhance the resolution of measurements of the particle size distribution. In addition, the IMS system will be coupled to a mass spectrometer so that particle mobility can be correlated with particle mass. The use of this new instrument will improve our fundamental understanding of aerosol and nanoparticle characterization and transport in the gas phase. The research team will conduct activities that demonstrate principles of aerosol science to K-12 students, especially those from underrepresented groups, in summer camps. The team will also communicate the role of aerosols in climate change and pollution through K-12 teacher/mentor awareness symposia.Aerosols are generally classified by size obtained from their mobility in the gas phase. Most often, mobility-based size distribution functions of aerosol particles are measured with a scanning mobility particle sizer (SMPS). While the SMPS has been highly successful, it has several shortcomings that could be addressed by employing different techniques. For example, diffusional broadening leads to a degradation in resolution for most operating commercial devices. Furthermore, SMPSs typically require minutes to complete voltage scans. This duration limits the information that can be obtained when aerosol samples vary rapidly in time, which can occur when sampling near aircraft or roadways. These challenges are exacerbated for measurements of PM0.1 particles in the gas phase. Despite continued experimental and theoretical interest, there is still a knowledge gap in the theoretical understanding of momentum transfer of particles that lie in the free molecular regime (1-100nm). The proposed research is expected to impact the aerosol field through increases in instrument separation/resolution by restricting diffusion broadening of nanoparticles, classifications of small aerosols through a mass-mobility and size relationship and quick, low signal-to-noise scans to study rapidly varying aerosols (up to tens of milliseconds per scan for particles smaller than 10 nanometers).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.

该项目的目标是开发一种新的仪器，以准确测量在各种环境应用中采样的纳米颗粒的尺寸分布。新仪器将提高100纳米以下超细颗粒（PM0.1颗粒）的灵敏度、选择性和检测速度。这种小尺寸的颗粒物来自产生较大颗粒物的相同天然或人为来源，但PM0.1颗粒物可能会对健康构成特殊威胁，因为它们很容易进入人体。改进的测量技术可以帮助检测和控制环境中的PM0.1颗粒。将开发的仪器是离子迁移谱仪（IMS）。 IMS将使用空间变化的电场来限制气相中颗粒的扩散，因此将提高颗粒尺寸分布测量的分辨率。此外，IMS系统将与质谱仪耦合，从而可以将粒子迁移率与粒子质量相关联。这种新仪器的使用将提高我们对气溶胶和纳米颗粒表征和气相传输的基本理解。研究团队将在夏令营中开展活动，向K-12学生，特别是来自代表性不足群体的学生，展示气溶胶科学的原理。该小组还将通过K-12教师/导师意识研讨会传达气溶胶在气候变化和污染中的作用。气溶胶通常根据其在气相中的流动性获得的大小进行分类。大多数情况下，气溶胶粒子的基于迁移率的尺寸分布函数是用扫描迁移率粒度仪（SMPS）测量的。虽然SMPS已经非常成功，但是它具有可以通过采用不同技术来解决的若干缺点。例如，扩散加宽导致大多数操作的商业设备的分辨率降低。此外，SMPS通常需要几分钟来完成电压扫描。这一持续时间限制了当气溶胶样品在时间上迅速变化时可以获得的信息，这可能发生在飞机或道路附近采样时。这些挑战对于气相中PM0.1颗粒的测量更加严峻。尽管持续的实验和理论的兴趣，仍然有一个知识的差距，在理论上理解的粒子的动量转移，位于自由分子制度（1- 100纳米）。拟议的研究预计将通过限制纳米颗粒的扩散加宽，通过质量流动性和尺寸关系对小气溶胶进行分类，低信噪比扫描研究快速变化的气溶胶（对于小于10纳米的颗粒，每次扫描时间长达数十毫秒）该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Flow-Optimized Model for Gas Jet Desorption Sampling Mass Spectrometry

气体喷射解吸采样质谱的流量优化模型

• DOI: 10.1021/acs.jpca.2c07999
• 发表时间: 2023
• 期刊: The Journal of Physical Chemistry A
• 作者: Chen, Xi;Newsome, G. Asher;Buchanan, Michael;Glasper, Jeremy;Hua, Leyan;Latif, Mohsen;Gandhi, Viraj;Li, Xintong;Larriba-Andaluz, Carlos
• 通讯作者: Larriba-Andaluz, Carlos

Enhancing Separation and Constriction of Ion Mobility Distributions in Drift Tubes at Atmospheric Pressure Using Varying Fields

• DOI: 10.1021/acs.analchem.2c00467
• 发表时间: 2022-04-12
• 期刊: ANALYTICAL CHEMISTRY
• 影响因子: 7.4
• 作者: Chen, Xi;Latif, Mohsen;Larriba-Andaluz, Carlos
• 通讯作者: Larriba-Andaluz, Carlos