A5051409058- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Atmospheric aerosols and clouds
- Atmospheric and Environmental Gas Dynamics
- Inhalation and Respiratory Drug Delivery
- Atmospheric Ozone and Climate
- Aerosol Filtration and Electrostatic Precipitation
- Catalysis and Oxidation Reactions
- Water Quality Monitoring and Analysis
- Combustion and flame dynamics
- Global Energy Security and Policy
- Indoor Air Quality and Microbial Exposure
- Infection Control and Ventilation
- Material Dynamics and Properties
- Various Chemistry Research Topics
- Radioactivity and Radon Measurements
- Agriculture, Land Use, Rural Development
- Geophysics and Gravity Measurements
- Supply Chain Resilience and Risk Management
- Regional Development and Management Studies
- Ionosphere and magnetosphere dynamics
- Combustion and Detonation Processes
- Liquid Crystal Research Advancements
- Theoretical and Computational Physics
University of Helsinki
2019-2024
University of Salzburg
2013-2024
Abstract Over Boreal regions, monoterpenes emitted from the forest are main precursors for secondary organic aerosol (SOA) formation and primary driver of growth new particles to climatically important cloud condensation nuclei (CCN). Autoxidation leads rapid Highly Oxygenated Molecules (HOM). We have developed first model with near-explicit representation atmospheric particle (NPF) HOM formation. The can reproduce observed NPF, gas-phase composition SOA over forest. During spring, increases...
Abstract. In the present-day atmosphere, sulfuric acid is most important vapour for aerosol particle formation and initial growth. However, growth rates of nanoparticles (<10 nm) from remain poorly measured. Therefore, effect stabilizing bases, contribution ions impact attractive forces on molecular collisions are under debate. Here, we present precise rate measurements uncharged particles 1.8 to 10 nm, performed atmospheric conditions in CERN (European Organization Nuclear Research)...
The Aerosol Dynamics in Containments (ADiC) model describes the dynamic changes of inhaled cigarette smoke droplets during puffing, mouth-hold, and inspiration expiration, considering coagulation, phase transition, conductive heat diffusive/convective vapor transport, dilution/mixing. ADiC has been implemented into a single path representation stochastic lung dosimetry IDEAL to compute particulate deposition as well airway generations human lung. In present study, applied inhalation...
Abstract. In this study we modeled secondary organic aerosol (SOA) mass loadings from the oxidation (by O3, OH and NO3) of five representative biogenic volatile compounds (BVOCs): isoprene, endocyclic bond-containing monoterpenes (α-pinene limonene), exocyclic double-bond compound (β-pinene) a sesquiterpene (β-caryophyllene). The simulations were designed to replicate an idealized smog chamber oxidative flow reactors (OFRs). Master Chemical Mechanism (MCM) together with peroxy radical...
Abstract. Atmospheric new particle formation occurs frequently in the global atmosphere and may play a crucial role climate by affecting cloud properties. The relevance of newly formed nanoparticles depends largely on dynamics governing their initial growth to sizes where they become important for microphysics. One key proper understanding nanoparticle effects is therefore hidden mechanisms. In this study we have developed successfully tested two independent methods based aerosol general...
Abstract A multitude of biogeochemical feedback mechanisms govern the climate sensitivity Earth in response to radiation balance perturbations. One mechanism, which remained missing from most current System Models applied predict future change IPCC AR6, is impact higher temperatures on emissions biogenic volatile organic compounds (BVOCs), and their subsequent effects hydroxyl radical (OH) concentrations. OH, turn, main sink term for many gaseous including methane, second important...
Abstract The oxidation of aromatics contributes significantly to the formation atmospheric aerosol. Using toluene as an example, we demonstrate existence a molecular rearrangement channel in mechanism. Based on both flow reactor experiments and quantum chemical calculations, show that bicyclic peroxy radicals (BPRs) formed OH-initiated aromatic are much less stable than previously thought, case derived ipso-BPRs, lead aerosol-forming low-volatility products with up 9 oxygen atoms sub-second...
The primary objectives of the present study were to mathematically describe particle coagulation within human respiratory tract and analyze its impact on local deposition patterns for high concentrations inhaled cigarette smoke particles. Coagulation mechanisms simulated thermal motion, gravitational settling, laminar shear, turbulences, electrical charges, inertial effects at airway bifurcations. To implement concentration dependent processes, Lagrangian random walk model IDEAL, simulating...
Abstract Comprehensive representation of nanoparticle dynamics is necessary for understanding nucleation and growth phenomena. This critical in atmospheric physics, as airborne particles formed from vapors have significant but highly uncertain effects on climate. While the vapor–particle mass exchange driving particle can be described by a macroscopic, continuous substance large enough particles, smallest nanoparticles involve stochastic fluctuations size due to discrete molecular collision...
Electronic cigarette (EC) aerosols are typically composed of a mixture nicotine, glycerine (VG), propylene glycol (PG), water, acidic stabilizers and variety flavors. Inhalation e-cigarette is characterized by continuous modification particle diameters, concentrations, composition phase changes, smoker-specific inhalation conditions, i.e. puffing, mouth-hold bolus inhalation. The dynamic changes inhaled droplets in the lungs due to coagulation, conductive heat diffusive heat/convective vapor...
Secondary organic aerosols (SOAs) influence the Earth's climate and threaten human health. Aromatic hydrocarbons (AHs) are major precursors for SOA formation in urban atmosphere. However, revealed oxidation mechanism dramatically underestimates contribution of AHs to formation, strongly suggesting importance seeking additional pathways formation. Using toluene, most abundant AHs, as a model system combination quantum chemical method field observations based on advanced mass spectrometry, we...
Abstract. In the present-day atmosphere, sulfuric acid is most important vapour for aerosol particle formation and initial growth. However, growth rates of nanoparticles (
Abstract. We introduce the Atmospherically Relevant Chemistry and Aerosol box model ARCA (v.1.2.2). It is a zero-dimensional process with focus on atmospheric chemistry submicron aerosol processes, including cluster formation. A novel feature in its comprehensive graphical user interface, allowing for detailed configuration documentation of simulation settings, flexible input, output visualization. Additionally, interface contains tools module customization input data acquisition. These...
Abstract. Atmospheric new particle formation occurs frequently in the global atmosphere and may play a crucial role climate by affecting cloud properties. The relevance of newly formed nanoparticles depends largely on dynamics governing their initial growth to sizes where they become important for microphysics. One key proper understanding nanoparticle effects is therefore hidden mechanisms. In this study we have developed successfully tested two independent methods based aerosol general...
For radiation protection purposes, the relative contributions of bronchial (BB), bronchiolar (bb) and alveolar-interstitial (AI) doses to lung cancer risk are represented by their corresponding apportionment factors. The current assumption equal factors can be tested comparing different radon thoron progeny exposures, which produce regional dose distributions, with pathologically observed distributions: (1) inhalation, (2) (3) exhalation (Thorotrast patients) (4) RP inhalation in rats,...
Abstract. In this study we modeled secondary organic aerosols (SOA) mass loadings from the oxidation (by O3, OH and NO3) of five representative Biogenic Volatile Organic compounds (BVOCs): isoprene, endocyclic bond containing monoterpenes (α-pinene limonene), exocyclic double compound (β-pinene) a sesquiterpene (β-caryophyllene). The simulations were designed to replicate idealized smog chamber oxidative flow reactors (OFR). master chemical mechanism (MCM) together with peroxy radical...
Aromatic compounds like xylene contribute significantly to the formation of tropospheric secondary organic aerosol (SOA) that have strong implications on health and climate. The sources this class molecules are primarily anthropogenic, but biogenic aromatics can be significant too. To form SOA, volatile needs oxidize into low volatility precursors with multiple oxygen containing polar functional groups called highly oxygenated (HOMs). It does through autoxidation mechanism, which is a...
In the last few decades, atmospheric formation of secondary organic aerosols (SOA) has gained increasing attention due to their impact on air quality and climate. However, methods predict abundance are mainly empirical may fail under real conditions. this work, a close-to-mechanistic approach allowing SOA quantification is presented, with focus chain-like chemical reaction called "autoxidation". A novel framework employed (a) describe gas-phase chemistry, (b) products' molecular structures...
Abstract. Autoxidation is key process that transforms volatile organic compounds into condensable species, thereby significantly contributing to the formation and growth of airborne particles. Given enormous complexity this chemistry, explicit reaction mechanisms describing autoxidation multitude atmospherically relevant precursors seem out reach. The present work suggests an alternative solution path: based on theoretically suggested types recent advances in mass spectroscopy,...
We applied the 1D model SOSAA to simulate atmospheric concentrations of OH, NO 3 , and H 2 SO 4 from 2007 2018 at SMEAR II. The results showed that daily OH increased by 2.39% per year decreased 3.41% 2.78% year, respectively.