Conference Agenda

This study compares ELPI’s electrical measurements (2 units equipped with different impaction plates) with well-established aerosol spectrometers, including MPSS, APSS, and CPC, using a set of well-defined aerosols of varying composition, size, and morphology.

Bioaerosols, which come from natural or industrial sources and consist of airborne organisms or their fragments, pose health risks to the public and industry. As a result, there is growing emphasis on developing reliable early detection methods for these pathogens. This project aims to create an affordable "first alert" system to detect airborne bacteria, fungi, and pollen in real time. The system alerts users to potential pathogens or allergens in the air, enabling timely protective actions. While it cannot identify specific types, it captures and stores particles in a liquid sample, which can then be analyzed in the laboratory

We have developed and applied a new measurement technique to determine the 3D shape factor of aerosol particles deposited on impactor trays using scanning electron microscopy (SEM). Besides the determination of two characteristic size of the particles from 2D SEM images, the Everhart-Thornley detector’s “shadow effect” was used to measure the height perpendicular to the Si substrate of the samples. From these informations a 3D shape factor was compiled, and used to determine the size-dependent 3D shape factors of particles emitted from three different dry powder inhalers and to study the shape factor’s effects on their lung deposition properties by numerical modelling.

In this work describe a high purity aerosolization, aerosol heating, and threshold condensation particle counting (CPC) system. We demonstrate the capability of this system using ultrapure water doped with varying concentrations of non-volatile and semi-volatile materials. When the aerosol is heated, the semi-volatile components may evaporate. This reduces the mean size of the aerosolized particle distribution and eventually, particle concentrations above the CPC size threshold fall below its detection limit. Materials tested include mixtures of sodium chloride, sucrose, and adipic and succinic acids. Aerosol temperatures range from 60-250°C.

The triboelectric charging of aerosol particles during particle-wall collisions can be used for basic investigations of the mechanical properties of nanoparticles, but also for the targeted charging of micrometer particles in a material-specific sorting process. In order to understand the charge transfer, the exit work of both contact partners must be known. Two methods for measuring the work function of aerosols and walls/powders at atmospheric pressure are presented here.