A Cost-effective, Miniature Electrical Ultrafine Particle Sizer (mini-eUPS) for Ultrafine Particle (UFP) Monitoring Network

Qiaoling Liu,Qiang Zhang,Jingkun Jiang,Xiaotong Chen,Di Liu,Da-Ren Chen

doi:10.4209/aaqr.2018.11.0427

Qiaoling Liu, Qiang Zhang + Show 4 more

Open Access

https://doi.org/10.4209/aaqr.2018.11.0427

Copy DOI

Abstract

ABSTRACT A cost-effective, miniature electrical ultrafine particle sizer (mini-eUPS) has been developed for future UFP (ultrafine particle) monitoring networks in cities with high traffic density and in communities close to freeways, airports or stationary combustion sources. The mini-eUPS mainly consists of a mini-plate unipolar particle charger, a mini-plate differential mobility classifier and a mini-particle Faraday cage with a sensitive electrometer. A custom-made circuit board was designed for operating the mini-eUPS. In addition to the primary function of measuring the UFP size distribution, the mini-eUPS records the temperature, relative humidity, pressure, altitude, timing and location for each measured data set. The operational status of the mini-eUPS is also registered for data quality assurance. Due to the built-in features of self-diagnosis, malfunction reporting and wireless networking, this particle sizer is suitable for UFP monitoring network. The prototype, which possesses overall dimensions of 6.5′′ (L) × 5.0′′ (W) × 4′′ (H) and a total weight of ~1.0 kg, measures particles ranging in size from 5 to 200 nm. To evaluate the performance of the mini-eUPS, size distribution measurements of lab-generated particles in both unimodal and bimodal distributions and of UFPs emitted from a low-cost 3D printer and diesel engine were compared with those taken by a Scanning Mobility Particle Sizer (SMPS; TSI Inc.). A reasonably good agreement between the mini-eUPS and SMPS data was found.

Highlights

To evaluate the performance of the mini-eUPS, size distribution measurements of lab-generated particles in both unimodal and bimodal distributions and of UFPs emitted from a low-cost 3D printer and diesel engine were compared with those taken by a Scanning Mobility Particle Sizer (SMPS; TSI Inc.)
The concern of adverse impact of ultrafine particles (UFPs, defined as particles in the sizes less than 100 nm) on the environment and health has been increasing in recent years as the number of scientific evidences published in the literature increased
Examples of integral instruments are condensation particle counters (CPCs), for total number concentration measurement; nanoparticle surface area monitors (NSAMs), for sensing total surface area concentration of particles deposited in a human lung; and electrical aerosol detectors (EADs), for measuring the total mass concentration of UFPs

Summary

INTRODUCTION

The concern of adverse impact of ultrafine particles (UFPs, defined as particles in the sizes less than 100 nm) on the environment and health has been increasing in recent years as the number of scientific evidences published in the literature increased. Examples of integral instruments are condensation particle counters (CPCs), for total number concentration measurement; nanoparticle surface area monitors (NSAMs), for sensing total surface area concentration of particles deposited in a human lung; and electrical aerosol detectors (EADs), for measuring the total mass concentration of UFPs. In addition, particleelectrical-mobility-based instruments (e.g., Electrical Aerosol Analyzer, EAA, and Differential Mobility Analyzer, DMA) have been widely applied in measuring the size distributions of UFPs. Electrical-mobility-based instruments in the portable version (listed in the Table 1) have been made available in recent years. Examples are at last given to demonstrate the overall performance of the mini-eUPS

MATERIALS AND METHODS

AND DISCUSSION