Nitrate-Enhanced Gas-to-Particle-Phase Partitioning of Water-Soluble Organic Compounds in Chinese Urban Atmosphere: Implications for Secondary Organic Aerosol Formation DOI

Shaojun Lv,

Can Wu, Fanglin Wang

et al.

Environmental Science & Technology Letters, Journal Year: 2022, Volume and Issue: 10(1), P. 14 - 20

Published: Dec. 29, 2022

To understand the gas-to-particle-phase partitioning process of water-soluble organic compounds (WSOCs) in atmosphere, we conducted simultaneous measurements gaseous WSOCs and particulate Shanghai during summer 2020. We found that pollution events (PEs) PM2.5 campaign can be classified as sulfate-dominated (SD) or nitrate-dominated (ND) episodes. The coefficients (Fp) ND episodes (0.36 ± 0.04) were 40% higher than those SD (0.25 0.05). These results largely driven by aerosol liquid water content acidity episodes, respectively. Such bulk-level are consistent with behaviors oxalic acid molecules PEs, demonstrating kinetics differed for two types PEs. thermodynamic model simulation Fp trend analysis composition revealed efficiency atmospheric throughout China past 20 years has increased increasing abundance nitrate relative to sulfate, indicating formation secondary aerosols will more efficient near future because increasingly WSOCs.

Language: Английский

A chemical cocktail during the COVID-19 outbreak in Beijing, China: Insights from six-year aerosol particle composition measurements during the Chinese New Year holiday DOI Open Access
Yele Sun,

Lu Lei,

Wei Zhou

et al.

The Science of The Total Environment, Journal Year: 2020, Volume and Issue: 742, P. 140739 - 140739

Published: July 4, 2020

Language: Английский

Citations

201
Laboratory Investigation of Renoxification from the Photolysis of Inorganic Particulate Nitrate DOI Creative Commons

Qianwen Shi,

Ye Tao, Jordan Krechmer

et al.

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(2), P. 854 - 861

Published: Jan. 4, 2021

Nitrogen oxides (NOx) play a key role in regulating the oxidizing capacity of atmosphere through controlling abundance O3, OH, and other important gas particle species. Some recent studies have suggested that particulate nitrate, which is conventionally considered as ultimate oxidation product NOx, can undergo "renoxification" via photolysis, recycling NOx HONO back to phase. However, there are large discrepancies estimates importance this channel, with reported renoxification rate constants spanning three orders magnitude. In addition, previous laboratory derived constant using bulk samples collected on substrates instead suspended particles. work, we study submicron sodium ammonium nitrate controlled photolysis experiments an environmental chamber. We find that, under atmospherically relevant wavelengths relative humidities, inorganic releases less than 10 times rapidly gaseous nitric acid, putting our measurements low end recently constants. To extent conditions representative real atmosphere, from appears limited contributing OH budgets remote environments. These results based simplified model systems; future should investigate more complex aerosol mixtures represent broader spectrum properties better constrain ambient aerosols.

Language: Английский

Citations

119
Gas-to-Aerosol Phase Partitioning of Atmospheric Water-Soluble Organic Compounds at a Rural Site in China: An Enhancing Effect of NH3 on SOA Formation DOI

Shaojun Lv,

Fanglin Wang, Can Wu

et al.

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(7), P. 3915 - 3924

Published: March 17, 2022

Partitioning gaseous water-soluble organic compounds (WSOC) to the aerosol phase is a major formation pathway of atmospheric secondary aerosols (SOA). However, fundamental mechanism WSOC-partitioning process remains elusive. By simultaneous measurements both gas-phase WSOC (WSOCg) and aerosol-phase (WSOCp) formic acetic acids at rural site in Yangtze River Delta (YRD) region China during winter 2019, we showed that WSOCg campaign dominantly partitioned dry period (relative humidity (RH) < 80%) but liquid water (ALW) humid (RH > 80%), suggesting two distinct SOA processes region. In period, temperature was driving factor for uptake WSOCg. contrast, factors controlling absorption were ALW content pH, which significantly elevated by NH3 through NH4NO3 neutralization with acids. Additionally, found relative abundances WSOCp strong linear correlation throughout spatial distribution consistent NH3, further indicating key role national scale. Since constitutes part SOA, such promoting effect on production elevating partitioning suggests emission control necessary mitigating haze pollution, especially China.

Language: Английский

Citations

85
Secondary Formation of Atmospheric Brown Carbon in China Haze: Implication for an Enhancing Role of Ammonia DOI Creative Commons
Xiaodi Liu, Haoyang Wang, Fanglin Wang

et al.

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(30), P. 11163 - 11172

Published: July 5, 2023

Optical characteristics and molecular compositions of brown carbon (BrC) were investigated during winter 2019 at a rural site China with focus on nitro-aromatic compounds (NACs) imidazoles (IMs). The abundance gaseous nitrophenols relative to CO the campaign maximized noontime, being similar O3, while particulate NACs haze periods strongly correlated toluene NO2, suggesting that in region are largely formed from gas-phase photooxidation. Strong correlations IMs dry mass ratio EC/PM2.5 concentration levoglucosan observed, indicating events derived biomass burning emissions. However, an increase increasing aerosol liquid water content pH was observed humid events, along much lower abundances K+ PM2.5, mostly aqueous reactions periods. These exponentially increased NH3 owing reaction carbonyls free ammonia. Our findings for first time revealed enhancing effect ammonia BrC formation China, especially

Language: Английский

Citations

44
Efficient Heterogeneous Formation of Ammonium Nitrate on the Saline Mineral Particle Surface in the Atmosphere of East Asia during Dust Storm Periods DOI
Can Wu, Si Zhang,

Gehui Wang

et al.

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(24), P. 15622 - 15630

Published: Nov. 30, 2020

To understand the chemical evolution of dust in current East Asian atmosphere, chemistry PM2.5 and size-resolved aerosols Shanghai, China, during 2019 storm event was investigated. Our results showed that concentrations SO42- city highly correlated with Ca2+ Na+ due to direct emissions CaSO4 Na2SO4 from upwind deserts. In contrast, event, NO3- linearly NH4+ at a molar ratio close 1:1, both almost entirely stayed coarse particles, suggesting they accumulated on surface as NH4NO3. Based field observations laboratory smog chamber simulations, we found NO2 O3 Shanghai period reacted form N2O5, which subsequently hydrolyzed into HNO3 saline mineral dusts (e.g., Na2SO4) further neutralized by NH3 The relative abundances were notably higher than those decade ago, indicating this heterogeneous formation NH4NO3 enhanced abundantly coexisting NOx, O3, should be considered future modeling studies.

Language: Английский

Citations

100
On the Relevancy of Observed Ozone Increase during COVID-19 Lockdown to Summertime Ozone and PM2.5 Control Policies in China DOI
Mingjie Kang, Jie Zhang, Hongliang Zhang

et al.

Environmental Science & Technology Letters, Journal Year: 2021, Volume and Issue: 8(4), P. 289 - 294

Published: March 24, 2021

In February 2020, China's strict lockdown policies led to significant reductions in anthropogenic nitrogen oxides (NOx) emissions, and notable increases surface ozone (O3) followed many urban areas, raising concerns about potential rises summertime O3 due NOx emission controls. On the basis of isopleths from a series air quality simulations under different levels volatile organic compound (VOC) reductions, we found that such are not necessary. As emissions have been reduced recent years for particulate matter control, future generally favorable maximum daily average 8-h (MDA8) reductions. Decreases will also lead lower atmospheric oxidation capacity, characterized by decreased OH NO3 concentrations, resulting further reduction secondary inorganic aerosols (nitrate, sulfate, ammonium ion, NSA) formation. VOC help reduce MDA8 needed control HCHO primary toxics simultaneously, but they ineffective reducing NSA. This study indicates nationwide policy has great controlling PM2.5 simultaneously. However, its effectiveness could be greatly when applied on limited spatial scale.

Language: Английский

Citations

78
Enhanced Nitrite Production from the Aqueous Photolysis of Nitrate in the Presence of Vanillic Acid and Implications for the Roles of Light-Absorbing Organics DOI
Yalin Wang, Dan Dan Huang,

Wanyi Huang

et al.

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(23), P. 15694 - 15704

Published: Nov. 17, 2021

A prominent source of hydroxyl radicals (

Language: Английский

Citations

59
Nitrate Photolysis in Mixed Sucrose–Nitrate–Sulfate Particles at Different Relative Humidities DOI
Zhancong Liang, Ruifeng Zhang, Masao Gen

et al.

The Journal of Physical Chemistry A, Journal Year: 2021, Volume and Issue: 125(17), P. 3739 - 3747

Published: April 26, 2021

Atmospheric particles can be viscous. The limitation in diffusion impedes the mass transfer of oxidants from gas phase to particle and hinders multiphase oxidation processes. On other hand, nitrate photolysis has been found effective producing such as OH radicals within particles. Whether effectively proceed viscous how it may affect physicochemical properties have not much explored. In this study, we investigated particulate mixed sucrose–nitrate–sulfate surrogates atmospheric containing organic inorganic components a function relative humidity (RH) molar fraction sucrose total solute (FSU) with an situ micro-Raman system. Sucrose suppressed crystallization, high rate constants (∼10–5 s–1) were found, irrespective RH. For FSU = 0.5 0.33 under irradiation at 30% RH, observed morphological changes droplets formation inclusions then likely "hollow" semisolid particles, which did show Raman signal central locations. Together states inorganics indicated by full width half-maxima (FWHM), images bulged surfaces, size increase optical microscopic imaging, inferred that hindered gaseous products (i.e., NOx, NOy) is reason for changes. implications these results are also presented.

Language: Английский

Citations

58
Rapid sulfate formation from synergetic oxidation of SO2 by O3 and NO2 under ammonia-rich conditions: Implications for the explosive growth of atmospheric PM2.5 during haze events in China DOI

Si Zhang,

Dapeng Li, Shuangshuang Ge

et al.

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 772, P. 144897 - 144897

Published: Jan. 29, 2021

Language: Английский

Citations

57
High atmospheric oxidation capacity drives wintertime nitrate pollution in the eastern Yangtze River Delta of China DOI Creative Commons

Han Zang,

Yue Zhao, Juntao Huo

et al.

Atmospheric chemistry and physics, Journal Year: 2022, Volume and Issue: 22(7), P. 4355 - 4374

Published: April 5, 2022

Abstract. Nitrate aerosol plays an increasingly important role in wintertime haze pollution China. Despite intensive research on nitrate chemistry recent years, quantitative constraints the formation mechanisms of Yangtze River Delta (YRD), one most developed and densely populated regions eastern China, remain inadequate. In this study, we identify major pathways their key controlling factors during winter period YRD using 2-year (2018–2019) field observations detailed observation-constrained model simulations. We find that high atmospheric oxidation capacity, coupled with liquid water content (ALWC), made both heterogeneous hydrolysis dinitrogen pentoxide (N2O5) gas-phase OH nitrogen dioxide (NO2) for region, contribution percentages 69 % 29 urban areas 63 35 suburban episodes, respectively. further gas-to-particle partitioning nitric acid (HNO3) was very efficient so rate-determining step overall process NOx to HNO3 through processes. The capacity (i.e., availability O3 radicals) factor production rate from During COVID-19 lockdown (January–February 2020), enhanced greatly promoted hence weakened response emission reductions areas. Our study sheds light highlights demand synergetic regulation emissions mitigate

Language: Английский

Citations

53