A number of pure salt aerosols were produced in the laboratory, subjected to a controlled humidity environment. The magnitude of the electrooptic response was measured continuously over a range of relative humidity (RH), which was varied from 20 to 90%, with an integrating electrooptical nephelometer. From such observations the influence of water vapor on the salt aerosols, especially the process of phase transition that occurs at the deliquescent point, can be monitored. The use of electrooptic scattering would appear to be a more sensitive indicator of the effect of water vapor on the aerosols at low RH than conventional light scattering intensity measurements.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/AO.19.001349 | DOI Listing |
Environ Sci Technol
January 2025
Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai 200241, China.
Mercury (Hg) is a neurotoxic pollutant that is ubiquitous on the planet and receives global concern because of its adverse health effects. Particle-bound Hg formation in the atmosphere stems mainly from the adsorption of reactive gaseous Hg on aerosol particles, particularly sea salt aerosol. However, the observed comparable abundance of Hg over Hg in the marine atmosphere has not been reproduced by traditional statistics-based schemes, which were constructed by continental observations.
View Article and Find Full Text PDFJ Occup Environ Hyg
January 2025
Metrology Research Centre, National Research Council Canada, Ottawa, Ontario, Canada.
Particle filtration efficiency (PFE) is a critical property of face masks, with the most common test methods using sodium chloride as a challenge aerosol. In the absence of bottom-up uncertainty budgets for PFE, interlaboratory comparisons provide an alternative route to robustly quantify the precision and bias of the method. This work presents the results of several interlaboratory comparisons of particle filtration efficiency performed across a network of laboratories.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.
In both nature and industry, aerosol droplets contain complex mixtures of solutes, which in many cases include multiple inorganic components. Understanding the drying kinetics of these droplets and the impact on resultant particle morphology is essential for a variety of applications including improving inhalable drugs, mitigating disease transmission, and developing more accurate climate models. However, the previous literature has only focused on the relationship between drying kinetics and particle morphology for aerosol droplets containing a single nonvolatile component.
View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Public Health Sciences, University of Rochester, School of Medicine and Dentistry, Rochester, NY, USA; Institute for a Sustainable Environment, Clarkson University, Potsdam, NY, USA.
Advanced receptor models can leverage the information derived from optical and chemical variables as input by a variety of instruments at different time resolutions to extract the source specific absorption Ångström exponent (AAE) from aerosol absorption. The multilinear engine (ME-2), a Positive Matrix Factorization (PMF) solver, serves as a proficient tool for performing such analyses, thereby overcoming the constraints imposed by the assumptions in current optical source apportionment methods such as the Aethalometer approach since the use of a-priori AAE values introduces additional uncertainty into the results of optical methods. Comprehensive PM chemical speciation datasets, and aerosol absorption coefficients (b, λ) at seven wavelengths measured by an Aethalometer (AE33), were used in multi-time source apportionment (MT-PMF).
View Article and Find Full Text PDFAn Acad Bras Cienc
December 2024
Universidade Federal do Rio Grande do Sul, Centro Polar e Climático, Av. Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!