Engine emissions with air pollutants and greenhouse gases and their control technologies

Journal of Cleaner Production, Journal Year: 2022, Volume and Issue: 376, P. 134260 - 134260

Published: Sept. 22, 2022

Language: Английский

---

Microphysical properties of atmospheric soot and organic particles: measurements, modeling, and impacts

npj Climate and Atmospheric Science, Journal Year: 2024, Volume and Issue: 7(1)

Published: March 8, 2024

Abstract Atmospheric soot and organic particles from fossil fuel combustion biomass burning modify Earth’s climate through their interactions with solar radiation modifications of cloud properties by acting as condensation nuclei ice nucleating particles. Recent advancements in understanding individual microscopic composition have led to heightened interest microphysical properties. This review article provides an overview current advanced measurements offers insights into future avenues for studying these To quantify morphology ageing, fractal dimension ( D f ) is a commonly employed quantitative metric which allows characterize morphologies aggregates relation ageing factors like internal mixing state, core-shell structures, phase, heterogeneity. Models been developed incorporate diversity metrics aged particles, enabling assessment optical absorption radiative forcing effects. The are complex they influenced particle sources, process, meteorological conditions. Furthermore, soluble exhibit diverse forms can engage liquid–liquid phase separation sulfate nitrate components. Primary carbonaceous such tar balls warrant further attention due strong light absorbing properties, presence toxic constituents, small size, impact human health. Future research needs include both atmospheric modeling approaches, focusing on changes the structures ensembles, effects dynamics

Language: Английский

---

Characterizing soil Cops Eco-risk in China

Journal of Hazardous Materials, Journal Year: 2025, Volume and Issue: 489, P. 137588 - 137588

Published: Feb. 11, 2025

Language: Английский

---

The effect of pressure up to 6 atm over soot maturity in laminar ethylene flames

Combustion and Flame, Journal Year: 2025, Volume and Issue: 274, P. 113977 - 113977

Published: Jan. 15, 2025

Language: Английский

---

Equal abundance of summertime natural and wintertime anthropogenic Arctic organic aerosols

Nature Geoscience, Journal Year: 2022, Volume and Issue: 15(3), P. 196 - 202

Published: Feb. 28, 2022

Abstract Aerosols play an important yet uncertain role in modulating the radiation balance of sensitive Arctic atmosphere. Organic aerosol is one most abundant, least understood, fractions mass. Here we use data from eight observatories that represent entire to reveal annual cycles anthropogenic and biogenic sources organic aerosol. We show during winter, dominated by emissions, mainly Eurasia, which consist both direct combustion emissions long-range transported, aged pollution. In summer, decreasing pollution replaced natural emissions. These include marine secondary, secondary primary biological have potential be climate modifying cloud condensation nuclei properties acting as ice-nucleating particles. Their source strength or atmospheric processing nutrient availability, solar radiation, temperature snow cover. Our results provide a comprehensive understanding current pan-Arctic aerosol, can used support modelling efforts aim quantify impacts this region.

Language: Английский

---

Enhanced Light Absorption and Radiative Forcing by Black Carbon Agglomerates

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(12), P. 8610 - 8618

Published: June 2, 2022

The climate models of the Intergovernmental Panel on Climate Change list black carbon (BC) as an important contributor to global warming based its radiative forcing (RF) impact. Examining closely these models, it becomes apparent that they might underpredict significantly direct RF for BC, largely due their assumed spherical BC morphology. Specifically, light absorption and agglomerates are enhanced by scattering between constituent primary particles determined Rayleigh-Debye-Gans theory interfaced with discrete dipole approximation recent relations refractive index lensing effect. is about 20% multiple regardless compactness agglomerates. resulting agrees very well observed aerosol optical depth BC. ECHAM-HAM simulations accounting realistic morphology coatings reveal high = 3-5 W/m2 in East, South Asia, sub-Sahara, western Africa, Arabian peninsula. These results agreement satellite AERONET observations indicate a regional contribution 0.75-1.25 °C, solely emissions.

Language: Английский

---

Elucidating the present-day chemical composition, seasonality and source regions of climate-relevant aerosols across the Arctic land surface

Environmental Research Letters, Journal Year: 2022, Volume and Issue: 17(3), P. 034032 - 034032

Published: Feb. 28, 2022

Abstract The Arctic is warming two to three times faster than the global average, and role of aerosols not well constrained. Aerosol number concentrations can be very low in remote environments, rendering local cloud radiative properties highly sensitive available aerosol. composition sources climate-relevant aerosols, affecting formation altering their microphysics, remain largely elusive due a lack harmonized concurrent multi-component, multi-site, multi-season observations. Here, we present dataset on overall chemical seasonal variability total particulate matter (with size cut at 10 μ m, PM , or without any cut) eight observatories representing all sectors. Our holistic observational approach includes Russian Arctic, significant emission source area with less dedicated aerosol monitoring, extends beyond more traditionally studied summer period black carbon/sulfate fine-mode pollutants. major airborne components terms dry mass are sea salt, secondary (non-sea-salt, nss) sulfate, organic (OA), minor contributions from elemental carbon (EC) ammonium. We observe substantial spatiotemporal component ratios, such as EC/OA, ammonium/nss-sulfate OA/nss-sulfate, fractional PM. When combined component-specific back-trajectory analysis identify marine terrestrial origins, companion study by Moschos et al 2022 Nat. Geosci. focusing OA, provides policy-guiding insights into sector-based differences natural anthropogenic sources. In this regard, first reveal regions inner-Arctic biogenic organics, highlight an underappreciated wintertime primary carbonaceous (EC OA) West Siberia, potentially associated oil gas sector. presented assist reducing uncertainties modelling pan-Arctic aerosol-climate interactions, contributors yearly These models then used predict future evolution individual atmospheric light current emerging pollution mitigation measures improved region-specific inventories.

Language: Английский

---

Validation of cantilever-enhanced photoacoustic particle-size-resolved light absorption measurement using nigrosin reference particles and Mie modelling

Aerosol Research, Journal Year: 2025, Volume and Issue: 3(1), P. 1 - 13

Published: Jan. 13, 2025

Abstract. Particle light absorption enhancement, also known as the lensing effect, is a complex phenomenon where particles undergo optical transformation they age. This process influenced by several factors, including particle size. To investigate this study introduces and validates novel method for size-resolved measurements using nigrosin model system. The combines three-wavelength cantilever-enhanced photoacoustic spectrometer (CEPAS) with differential mobility analyser (DMA) to achieve particle-size-resolved measurements. Nigrosin, well-characterised, spherically shaped, water-soluble material, was selected demonstrate feasibility precision of approach. system showed strong agreement (R2>0.94) Mie-modelled absorption, confirming its reliability. While broader motivation work lies in advancing techniques studying ageing, coating, enhancement black carbon other atmospheric aerosols, present serves foundational step validating methodology controlled simplified context. Future studies will expand application systems, coated aggregated particles, explore phenomena such enhancement.

Language: Английский

---

Soot PCF: pore condensation and freezing framework for soot aggregates

Atmospheric chemistry and physics, Journal Year: 2021, Volume and Issue: 21(10), P. 7791 - 7843

Published: May 21, 2021

Abstract. Atmospheric ice formation in cirrus clouds is often initiated by aerosol particles that act as ice-nucleating particles. The aerosol–cloud interactions of soot and associated feedbacks remain uncertain, part because a coherent understanding the nucleation mechanism activity has not yet emerged. Here, we provide new framework predicts on via pore condensation freezing (PCF) that, unlike previous approaches, considers particle properties, capturing their vastly different properties compared to other species such mineral dust. During PCF, water taken up into pores aggregates capillary condensation. At temperatures, can freeze homogeneously subsequently grow macroscopic crystal. In soot-PCF presented here, relative humidity conditions required for these steps are derived types function temperature. considered here encompass n-membered ring form between n individual spheres within same layer primary well inner cavities two layers We treat perfect use contact angle (θsw), diameter (Dpp), degree overlap (overlap coefficient, Cov) characterize properties. find three-membered four-membered right size assuming sizes typical atmospheric For types, derive equations describe all three namely condensation, nucleation, growth. Since at homogeneous be immediate soon volume large enough host critical embryo, PCF becomes limited either or crystal equation parameterize based routinely measured, including size, overlap, fractal dimension. These along with number making an aggregate soot, constrain parameterization. Applying parameterization previously reported laboratory data provides direct evidence takes place PCF. conclude this clarifies perspective represent climate models.

Language: Английский

---

Elucidating the polycyclic aromatic hydrocarbons involved in soot inception

Communications Chemistry, Journal Year: 2023, Volume and Issue: 6(1)

Published: Oct. 16, 2023

Polycyclic aromatic hydrocarbons are the main precursors to soot particles in combustion systems. A lack of direct experimental evidence has led controversial theoretical explanations for transition from gas-phase species organic clusters. This work focuses on sampling infant well-defined flames followed by analysis using state-of-the-art mass spectrometry. We found that PAH molecules present all stabilomers. Kinetic Monte Carlo simulations and thermodynamic stability calculations further identify detected PAHs as peri-condensed without aliphatic chains. Van der Waals forces can easily link such size shape form dimers larger clusters under specified flame conditions. Our results provide inception is initiated a physical process typical improves our understanding aerosol particulates, which implications their environmental climate change impacts.

Language: Английский

---