GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Copernicus GmbH  (3)
  • 2020-2024  (3)
Material
Publisher
  • Copernicus GmbH  (3)
Person/Organisation
Language
Years
  • 2020-2024  (3)
Year
  • 1
    Online Resource
    Online Resource
    The shifting of secondary inorganic aerosol formation mechanisms during haze aggravation: the decisive role of aerosol liquid water
    Copernicus GmbH ; 2023
    In:  Atmospheric Chemistry and Physics Vol. 23, No. 4 ( 2023-02-21), p. 2365-2378
    Details
    In: Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 23, No. 4 ( 2023-02-21), p. 2365-2378
    Abstract: Abstract. Although many considerable efforts have been done to reveal the driving factors on haze aggravation, however, the roles of aerosol liquid water (ALW) in secondary inorganic aerosol (SIA) formation were mainly focused on the condition of aerosol liquid water content (ALWC) 〈 100 µg m−3. Based on the in situ high-resolution field observations, this work studied the decisive roles and the shifting of secondary inorganic aerosol formation mechanisms during haze aggravation, revealing the different roles of ALWC on a broader scale (∼500 µg m−3) in nitrate and sulfate formation induced by aqueous chemistry in the ammonia-rich atmosphere. The results showed that chemical domains of perturbation gas limiting the generation of secondary particulate matter presented obvious shifts from a HNO3-sensitive to a HNO3- and NH3-co-sensitive regime with the haze aggravation, indicating the powerful driving effects of ammonia in the ammonia-rich atmosphere. When ALWC 〈 75 µg m−3, the sulfate generation was preferentially triggered by the high ammonia utilization and then accelerated by nitrogen oxide oxidation from clean to moderate pollution stages, characterized by nitrogen oxidation ratio (NOR) 〈 0.3, sulfur oxidation ratio (SOR) 〈 0.4, ammonia transition ratio (NTR) 〈 0.7 and the moral ratio of NO3-/SO42-=2:1. When ALWC 〉 75 µg m−3, the aqueous-phase chemistry reaction of SO2 and NH3 in ALW became the prerequisite for SIA formation driven by Henry's law in the ammonia-rich atmosphere during heavy and serious stages, characterized by high SOR (0.5–0.9), NOR (0.3–0.5) and NTR (〉0.7), as well as the high moral ratio of NO3-/SO42-=1:1. A positive feedback of sulfate on nitrate production was also observed in this work due to the shift in ammonia partitioning induced by the ALWC variation during haze aggravation. It implies the target controlling of haze should not simply focus on SO2 and NO2, but more attention should be paid to gaseous precursors (e.g., SO2, NO2, NH3) and aerosol chemical constitution during different haze stages.
    Type of Medium: Online Resource
    ISSN: 1680-7324
    URL: Article
    URL: Article
    DOI: 10.5194/acp-23-2365-2023
    DOI: 10.5194/acp-23-2365-2023-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2023
    detail.hit.zdb_id: 2092549-9
    detail.hit.zdb_id: 2069847-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Chemical characteristics and sources of PM 2.5 in Hohhot, a semi-arid city in northern China: insight from the COVID-19 lockdown
    Copernicus GmbH ; 2022
    In:  Atmospheric Chemistry and Physics Vol. 22, No. 18 ( 2022-09-19), p. 12153-12166
    Details
    In: Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 22, No. 18 ( 2022-09-19), p. 12153-12166
    Abstract: Abstract. A knowledge gap exists concerning how chemical composition and sources respond to implemented policy control measures for aerosols, particularly in a semi-arid region. To address this, a single year's offline measurement was conducted in Hohhot, a semi-arid city in northern China, to reveal the driving factors of severe air pollution in a semi-arid region and assess the impact of the COVID-19 lockdown measures on chemical characteristics and sources of PM2.5. Organic matter, mineral dust, sulfate and nitrate accounted for 31.5 %, 14.2 %, 13.4 % and 12.3 % of the total PM2.5 mass, respectively. Coal combustion, vehicular emission, crustal source and secondary inorganic aerosols were the main sources of PM2.5 in Hohhot, at 38.3 %, 35.0 %, 13.5 %, and 11.4 %, respectively. Due to the coupling effect of emission reduction and improved atmospheric conditions, the concentration of secondary inorganic components, organic matter and elemental carbon declined substantially from the pre-lockdown (pre-LD) period to the lockdown (LD) and post-lockdown (post-LD) periods. The source contribution of secondary inorganic aerosols increased (from 21.1 % to 37.8 %), whereas the contribution of vehicular emission reduced (from 35.5 % to 4.4 %) due to lockdown measures. The rapid generation of secondary inorganic components caused by unfavorable meteorological conditions during lockdown led to serious pollution. This study elucidates the complex relationship between air quality and environmental policy.
    Type of Medium: Online Resource
    ISSN: 1680-7324
    URL: Article
    URL: Article
    DOI: 10.5194/acp-22-12153-2022
    DOI: 10.5194/acp-22-12153-2022-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2022
    detail.hit.zdb_id: 2092549-9
    detail.hit.zdb_id: 2069847-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    The evolutionary behavior of chromophoric brown carbon during ozone aging of fine particles from biomass burning
    Copernicus GmbH ; 2020
    In:  Atmospheric Chemistry and Physics Vol. 20, No. 8 ( 2020-04-21), p. 4593-4605
    Details
    In: Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 20, No. 8 ( 2020-04-21), p. 4593-4605
    Abstract: Abstract. Biomass burning (BB) emits large amounts of brown carbon (BrC); however, the evolutionary behavior of BrC in BB emissions (BB BrC) resulting from complex atmospheric processes is poorly understood. In this study, the transformation of contents and the chromophoric characteristics of BrC in smoke particles emitted by the burning of rice straw (RS), corn straw (CS), and pinewood (PW) under O3 aging are investigated. The O3 aging induced the reduction of light absorption and fluorescence for the BB BrC, suggesting the decomposition of chromophores and fluorophores. These changes were accompanied by a decrease in aromaticity, average molecular weight, and the light absorption capacity for the chromophores, as well as an increase in humification for the fluorophores. The excitation emission matrix combined with a parallel factor analysis revealed that protein-like components (C3) were predominantly decomposed by O3 aging, while the relative distribution of a humic-like component with highly oxygenated chromophores (C4) gradually increased. In general, the humic-like substances (C1 + C2 + C4) were transformed to be the most abundant fluorophores for all the BB BrC samples, which accounted for 84 %–87 % of the total fluorophores in final O3-aged BB BrC. Two-dimensional correlation spectroscopy (2D-COS) was performed on the synchronous fluorescence, which suggested that the RS and CS BrC exhibits the same susceptible fluorophores changes upon O3 aging. It showed that O3 firstly reacted with protein-like fractions (263–289 nm) and then with fulvic-like fractions (333–340 nm). In comparison, the changing sequence of susceptible fluorophores in the PW BrC to O3 was in the order of fulvic-like fluorophores with shorter wavelengths (309 nm), protein-like fluorophores (276 nm), and fulvic-like fluorophores with longer wavelengths (358 nm). The 2D-FTIR-COS (2D-COS combined with FTIR) analysis showed conjugated C=O and aromatic C=C and C=O groups were the most susceptible functional groups to O3 aging for all BB BrC. Moreover, it also revealed a consistent sequential change, which is in the order of aromatic OH; conjugated C=O groups and aromatic C=O; aromatic COO−; and finally lignin-derived C–C, C–H, and C–O groups. Our results provide new insights into the evolutionary behavior of the chromophoric and fluorescent properties of BB BrC during O3 aging, which are of great significance for better understanding the heterogeneous oxidation pathways of BB-derived BrC in the atmospheric environment.
    Type of Medium: Online Resource
    ISSN: 1680-7324
    URL: Article
    URL: Article
    DOI: 10.5194/acp-20-4593-2020
    DOI: 10.5194/acp-20-4593-2020-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2020
    detail.hit.zdb_id: 2092549-9
    detail.hit.zdb_id: 2069847-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...