A5085465656- Atmospheric chemistry and aerosols
- nanoparticles nucleation surface interactions
- Air Quality and Health Impacts
- Laser-induced spectroscopy and plasma
- Aerosol Filtration and Electrostatic Precipitation
- Atmospheric aerosols and clouds
- Infection Control and Ventilation
- Atmospheric and Environmental Gas Dynamics
- Vehicle emissions and performance
- Laser-Ablation Synthesis of Nanoparticles
- Aerodynamics and Acoustics in Jet Flows
- Oil, Gas, and Environmental Issues
- Combustion and flame dynamics
- Gas Dynamics and Kinetic Theory
- Spectroscopy and Laser Applications
- Catalytic Processes in Materials Science
- Advanced Optical Sensing Technologies
- Cyclone Separators and Fluid Dynamics
- Radiative Heat Transfer Studies
- Water Systems and Optimization
- Advanced Combustion Engine Technologies
- Spacecraft and Cryogenic Technologies
- COVID-19 and healthcare impacts
- Urban Stormwater Management Solutions
- Seismic Imaging and Inversion Techniques
National Research Council Canada
2021-2025
University of British Columbia
2019-2023
University of Waterloo
2012-2023
Pennsylvania State University
2023
University of Alberta
2021
Combustion and other high-temperature processes can produce solid aerosol nanoparticles with complex morphologies, including fractal-like aggregates of primary particles. Characterizing these as well particle mass, is key to understanding their behavior in natural engineered systems, it provide clues the origin We focus here on characterization soot, although most techniques apply aggregates. A complete description aerosols would include mass morphology every particle. In practice, possible...
Laser-induced incandescence (LII) is a widely used combustion diagnostic for in situ measurements of soot primary particle sizes and volume fractions flames, exhaust gases, the atmosphere. Increasingly, however, it applied to characterize engineered nanomaterials, driven by increasing industrial relevance these materials fundamental scientific insights that may be obtained from measurements. This review describes state art as well open research challenges new opportunities arise LII on...
The mass concentration of soot aggregates is often estimated from mobility size distributions using a mobility-based effective density, ρeff. This ρeff changes with aggregate morphology. In particular, the core increases when it becomes compacted by surface tension condensing coatings, such as combustion-related vapours, secondary aerosols, and cloud water. extent this compaction function coating volume, up to an asymptotic limit complete compaction. While has previously been shown...
Black carbon (BC) is a strongly absorbing component of atmospheric aerosols that has significant warming effect. BC particles are emitted from combustion sources as open-structured fractal aggregates. After emission, often compacted due to capillary condensation semivolatile vapors form coatings. The addition coatings influences the size and radiative properties BC, but representing these details in transfer models computationally difficult neglected. Laboratory studies have measured...
Particle filtration efficiency (PFE) is a critical property of face masks, with the most common test methods using sodium chloride as challenge aerosol. In absence bottom-up uncertainty budgets for PFE, interlaboratory comparisons provide an alternative route to robustly quantify precision and bias method. This work presents results several particle performed across network laboratories. Using log-penetration surrogate it shown that expanded reproducibility intervals were consistent samples,...
Photothermal spectroscopy, and photothermal interferometry (PTI) in particular, has the potential to provide reference measurements of aerosol absorption coefficients βabn. Such βabn represent a fundamental property aerosols such as black carbon brown carbon, accurate knowledge which is essential for understanding their climate forcing: can be used calculating imaginary refractive index, function, or mass cross-section sample. Furthermore, commonly expressed units equivalent (eBC) many...
Conditional Source-term Estimation (CSE) obtains the conditional species mass fractions by inverting a Fredholm integral equation of first kind. In present work, Bayesian framework is used to compare two different regularisation methods: zeroth-order temporal Tikhonov regulatisation and first-order spatial regularisation. The objectives current study are: (i) elucidate ill-posedness inverse problem; (ii) understand origin perturbations in data quantify their magnitude; (iii) uncertainty...
This article provides an overview of methods to evaluate transfer functions for the Couette centrifugal particle mass analyzer (CPMA) and aerosol (APM). The work first considers finite difference approaches solving partial differential equation governing motion, which represents accurate but computationally-demanding approach evaluating function. is used as a baseline compare tracking methods, have been shown yield closed form expressions In this work, we extend on previous treatments by...
Aerosolized metal nanoparticles have numerous existing and emerging applications in materials science, but their functionality these roles is strongly size-dependent. Very recently, time-resolved laser-induced incandescence (TiRe-LII) has been investigated as a candidate for sizing aerosolized nanoparticles, which requires an accurate model of the heat transfer through laser-energized particles re-equilibrate with bath gas. This paper presents such molybdenum then used to analyze...
This paper presents a novel error model for TiRe-LII signals and illustrates how the can be used to diagnose detection system, quantify uncertainties in TiRe-LII, characterize fluctuations measured process. Noise single measurement shot obeys Poisson–Gaussian noise model. Variation aerosol results shot-to-shot signals. These induce quadratic relationship between mean variance of set We show this elucidate aspects system fundamental properties aerosol, by comparing four sets experimental data.