An integrated observation of aerosol aminiums was
conducted in a coastal city (Shanghai) in eastern China, a nearby island
(Huaniao Island), and over the Yellow Sea and East China Sea (YECS).
Triethylaminium (TEAH+) was abundant over Shanghai but not detected
over the island and the open seas, suggesting its predominantly terrestrial
origin. By contrast, relatively high concentrations of dimethylaminium
(DMAH+) and trimethylaminium + diethylaminium (TMDEAH+) were
measured over the ocean sites, indicating the significant marine source
contribution. Environmental factors, including boundary layer height (BLH),
temperature, atmospheric oxidizing capacity and relative humidity, were
found to be related to aminium concentrations. All the detected aminiums
demonstrated the highest levels in winter in Shanghai, consistent with the
lowest BLH and temperature in this season. Aminiums mainly existed in fine
particles and showed a bimodal distribution, with two peaks at 0.18–0.32 µm and 0.56–1.0 µm, indicating that condensation and cloud
processing were the main formation pathways for aminiums in analogy with
NH4+ and non-sea-salt SO42- (nss-SO42-).
Nonetheless, a unimodal distribution for aerosol aminiums was usually
measured over the YECS or over Huaniao Island when influenced mainly by
the marine air mass, which suggested that aminiums in marine aerosols may
undergo different formation pathways from those on the land. Terrestrial
anthropogenic sources and marine biogenic sources were both important
contributors for DMAH+ and TMDEAH+, and the latter exhibited a
significantly higher TMDEAH+ to DMAH+ ratio. By using the mass
ratio of methanesulfonate (MSA) to nss-SO42- as an indicator of
marine biogenic source, we estimated that marine biogenic source contributed
to 26 %–31 % and 53 %–78 % of aerosol aminiums over Huaniao Island in the
autumn of 2016 and summer of 2017, respectively. Due to the important role
of atmospheric amines in new particle formation, the estimation results
highlighted the importance of marine biogenic emission of amines on the
eastern coast of China, especially in summer.
Introduction
Low molecular weight amines are commonly found in the atmosphere in both gas
and particle phases (Ge et al., 2011a, b). Based on present theoretical
calculations (Kurtén et al., 2008; Loukonen et al., 2010; Paasonen et al.,
2012; Olenius et al., 2017), laboratory simulations (Wang et al., 2010a, b; Kurtén et al., 2014; Erupe et al., 2011; Almeida et al.,
2013; Yu et al., 2012) and field observations (Smith et al., 2010;
Kürten et al., 2016; Tao et al., 2016), amines in the atmosphere have
been proved to play an important role in new particle formation and
subsequent particle growth and thus affect both the number concentrations
of aerosols and cloud condensation nuclei that are closely relevant to
regional climate (Tang et al., 2014; Yao et al., 2018). For example,
dimethylamine (DMA) was found to be a key species involved in new particle
formation events in the urban area of Shanghai, and the nucleation mechanism
was likely to be H2SO4–DMA–H2O ternary nucleation (Yao et
al., 2018). Gaseous amines in the atmosphere can react with oxidants such as
⚫OH and O3 to form secondary organic aerosols (SOA) (Murphy
et al., 2007) or gaseous oxidation products such as imines, formamides,
nitrosamines and nitramines (Nielsen et al., 2012). In aerosols, amines are
mainly in the form of protonated cations, namely aminiums (Ge et al.,
2011a), and the formation of aminium salts from an acid–base reaction or
heterogeneous reaction, such as replacing the NH4+ in particles,
is another important pathway for amines to form SOA in the atmosphere
(Pankow, 2015; Kupiainen et al., 2012; Liu et al., 2012; Chan and Chan,
2013).
Amines originate from a wide range of sources, including anthropogenic
sources such as animal husbandry and industrial emissions, as well as
natural sources such as marine sources, vegetation emissions and soil
processing (Ge et al., 2011b; Hemmilä et al., 2018). Dawson et al. (2014) measured concentrations of trimethylamine (TMA, 1.3–6.8 ppt)
near a cattle farm, which were 2–3 orders of magnitude higher than those in
ambient environments. Shen et al. (2017) demonstrated that coal combustion
could emit abundant methylaminium (MMAH+), ethylaminium (MEAH+)
and diethylaminium (DEAH+) through combustion experiments, and the
corresponding emission factors were 18.0±16.4, 30.1±25.6 and
14.6±10.1 mg (kg coal)-1, respectively. In the marine boundary
layer, marine source is an important contributor for amines and it was found
to be closely related to the biological activities on the ocean surface. In the
North Atlantic, the concentrations of dimethylaminium (DMAH+) and
DEAH+ were significantly higher during the periods with high biological
activity and clean air masses than those with low biological activity or
polluted air masses advecting to the sampling site, and the contributions of
these two aminiums to SOA and water-soluble organic nitrogen (WSON) reached
11 % and 35 %, respectively (Facchini et al., 2008). The observation in
Cabo Verde also showed that the concentrations of aminiums were higher
during the occurrence of algal blooms (Müller et al., 2009). In addition
to gas-to-particle conversion, which has been generally considered to be the
major formation pathway (Facchini et al., 2008; Rinaldi et al., 2010),
aminiums in the marine boundary layer may also be generated with primary marine
aerosols. For example, Fourier transform infrared (FTIR) spectroscopy
measurements demonstrated that the submicron organic carbon was composed of
50 % hydroxyl, 33 % alkane, and 14 % amine in nascent sea spray
aerosols artificially generated off the California coast (Bates et al.,
2012) and of 55 % hydroxyl, 32 % alkane, and 13 % amine over the open
ocean (Frossard et al., 2014). Aerosol time-of-flight mass spectrometry
(ATOFMS) analyses of ambient aerosols in the Antarctic sympagic environment
also indicated that 11 %–25 % of aminiums were contributed by primary
marine source (Dall'Osto et al., 2019).
Map of sampling sites and area. The red stars represent
the locations of Shanghai (Fudan University) and Huaniao Island, and the
black line in the surrounding marginal seas represents the cruise track in the spring of
2017.
Given the potentially important roles of amines in the atmosphere and the
complexity of their sources, it is important to conduct a systematic
analysis of their concentrations, affecting factors, formation pathways and
source contributions. Eastern China is a densely populated region with
strong human activity and large emissions of atmospheric pollutants. Under
the influence of the summer monsoon, marine source components can be vital
to the atmospheric composition of the coastal area. Although the lifetime of
gaseous amines in the atmosphere is only a few hours, it can be prolonged
after amines partition into the particle phase, and thus they may be
transported over a long range (Nielsen et al., 2012). Many studies have been
done on the gas and/or particle phases of amines over eastern China and
adjacent seas (Huang et al., 2012, 2016; Hu et al., 2015; Zheng et al., 2015; Tao et al., 2016; Yu et al., 2016; Shen et al., 2017;
Xie et al., 2018; Yao et al., 2016, 2018). For example, C1 to
C6 amines over Shanghai were measured during the summer of 2015, of which
C1, C2 and C4 amines were the dominant species with average
concentrations of 15.7, 40.0 and 15.4 ppt, respectively (Yao et al., 2016).
Zheng et al. (2015) measured an average concentration 7.2 ppt of total
amines in a suburban site of Nanjing during the summer of 2012, derived
mainly from industrial emissions in adjacent areas. The aminiums in fine
particles over Shanghai in the summer of 2013 were found to exhibit a high
concentration (mean 86.4 ng m-3) and play an important role in the
new particle formation events (Tao et al., 2016). Previous studies on
aminiums over the marginal seas off the coast of China indicated that DMAH+ and
trimethylaminium (TMAH+) were overwhelmingly from marine sources (Hu et
al., 2015; Yu et al., 2016; Xie et al., 2018). In May 2012, the
concentrations of DMAH+ and TMAH+ over the Yellow Sea (YS) and
Bohai Sea even reached 4.4 and 7.2 nmol m-3, which was 1–3 orders of
magnitude higher than those reported in other oceanic regions (Hu et al.,
2015). These extremely high concentrations were thought to be associated
with high biological activities. In spite of these field studies,
long-term observations of aminiums over coastal seas and the quantitative
estimates of the contribution of marine biogenic source to aerosol aminiums
are still lacking.
In this study, the aminiums over a coastal megacity (Shanghai), a nearby
island (Huaniao Island) and surrounding marginal seas (the Yellow Sea and East China
Sea, YECS) were measured. The relationships between aminium concentrations
and environmental factors were systematically analyzed. The size
distributions of aminiums were investigated with speculation on the main
formation pathways. Aside from this, the dominant sources determining the
concentrations and ratios between aminium species were elucidated, and the
contributions of terrestrial anthropogenic and marine biogenic sources to
aminiums were quantitatively estimated. Our results will be a great help for
understanding the chemical properties, reaction pathways, and sources of
aerosol aminiums over the coastal area and the ocean.
Sampling and analysisAerosol sampling
The sampling site in Shanghai was located on top of the No. 4 teaching
building of Fudan University (31.30∘ N, 121.50∘ E) (Fig. 1). This site is affected by the school, residential, commercial and traffic
activities and can be taken as representative of coastal cities. Particulate matter
with an aerodynamic diameter less than 2.5 µm (PM2.5) was
simultaneously collected by two medium-flow samplers (100 L min-1,
HY-120B, Hengyuan) using a 90 mm pre-combusted quartz filter (Whatman) and a
cellulose filter (Grade 41, Whatman), respectively. A total of 131 samples
were collected within four seasons with a sampling duration of around 24 h (spring: 25 March–26 April 2013; summer: 16 July–17 August 2013;
autumn: 30 October–30 November 2013; winter: 1 December 2013–23 January 2014)
(Table 1).
Summary of sampling information from the different campaigns.
Sampling siteSamplerSampling periodNumber of samplesor sample setsFudan University, ShanghaiMedium-flow PM2.5 sampler25 March–26 April 2013 (spring)2916 July–17 August 2013 (summer)2630 October–30 November 2013(autumn)291 December 2013–23 January 2014 (winter)37Huaniao IslandMedium-flow PM2.5 sampler4–18 August 2016(summer)14Huaniao IslandMOUDI12 November–3 December 2016 (autumn)911–19 March 2017 (spring)422 June–9 July 2017(early summer)827 August–12 September 2017 (late summer)7Yellow Sea and East China SeaMOUDI27 March–14 April 2017(spring)9
Aerosols were also collected on Huaniao Island (HNI, 30.86∘ N,
121.67∘ E), which is about 80 km away from Shanghai in the East
China Sea (ECS) (Fig. 1). The locally anthropogenic emissions were
negligible, but the site was affected by the terrestrial transport and the
ship emissions from nearby container ports (Wang et al., 2016, 2018). PM2.5 samples were collected in the summer of 2016 (4–18 August) and size-segregated samples were obtained using a 10-stage
Micro-Orifice Uniform Deposit Impactor (30 L min-1, MOUDI, MSP Model
110-NR) and 47 mm PTFE filters (Zeflour, PALL) in the autumn of 2016 (12
November–3 December), the spring of 2017 (11–19 March) and early and
late summer 2017 (22 June–9 July and 27 August–12 September, respectively)
(Table 1). The 50 % cutoff diameters for the 10 stages were 18, 10, 5.6, 3.2,
1.8, 1.0, 0.56, 0.32, 0.18, 0.10 and 0.056 µm and the sampling
durations were 24–48 h.
The size-segregated samples were also collected over the YECS on board
research vessel (R/V) Dongfanghong II in the spring of 2017. The cruise started from
Qingdao on 27 March and returned on 15 April (Fig. 1), and a total of nine sets
of samples were obtained.
Chemical analysis
One-fourth of PM2.5 and half of MOUDI sample filters were cut and
placed into a polypropylene jar (Nelgene) with 15 and 20 mL of ultrapure
water (18.25 MΩ cm-1), respectively, for a 40 min ultrasonic
extraction. The extract was filtered through a 0.45 µm PTFE filter
(Jinteng) and stored at 4∘ for ion measurement. An ion chromatograph
(IC, DIONEX ICS-3000, Thermo Fisher) assembled with AG11-HC and AS11-HC was used
to determine anions, including Cl-, NO3-, SO42-,
HCOO-, methanesulfonate (MSA), malonate, succinate, glutarate, maleate
and C2O42-. The columns CG17 and CS17 were used to measure
inorganic cations including Na+, NH4+, K+, Mg2+ and
Ca2+ and aminiums. Six aminiums, including DMAH+,
TMAH++ DEAH+, propylaminium (MPAH+), triethylaminium
(TEAH+), ethanolaminium (MEOAH+) and triethanolaminium
(TEOAH+), could be effectively separated and measured using the IC
method. The MMAH+ and MEAH+ in the aerosols could not be
quantified because their peaks were obscured by the wide and distorted peak
of NH4+. It should be noted that TMAH+ and DEAH+ could
not be completely separated using the IC system (VandenBoer et al., 2011, 2012; Zhou et al., 2018; Huang et al., 2014). Therefore,
the sum of TMAH+ and DEAH+ concentrations (TMDEAH+)
were quantified using the calibration curve of TMAH+ with errors less
than 3 % (Zhou et al., 2018). With the sampling volumes of 144 and 86 m3 for PM2.5 and MOUDI samples, respectively, the detection limits
of DMAH+, TMDEAH+, TEAH+, MPAH+, MEOAH+ and
TEOAH+ were 0.55, 0.78, 1.93, 2.59, 1.94 and 4.96 ng m-3 for
PM2.5 samples and 0.20, 0.29, 0.71, 0.95, 0.56 and 1.82 ng m-3 for
samples collected in each MOUDI stage. MPAH+, MEOAH+ and
TEOAH+ were rarely detected in the aerosol samples (<10 %)
and thereby not reported in this study. Detailed information about
analysis of aminiums is given in Zhou et al. (2018).
One-fourth of the PM2.5 cellulose sample filter was cut and digested with 7
mL of HNO3 and 1 mL of HF (both acids were purified from GR using a
sub-boiling system) at 185 ∘C for 30 min in a microwave digestion
system (MARS5 Xpress, CEM). Inductively coupled plasma optical emission
spectroscopy (ICP-OES, SPECTRO) was used for determining the following elements: Al, Ca,
Fe, Na, P, S, Cu, K, Mg, Mn, Zn, As, Ba, Cd, Ce, Co, Cr, Mo, Ni, Pb, Ti and
V. The detailed procedures refer to Wang et al. (2016).
Auxiliary data
The 3 h resolution meteorological data from Baoshan station in Shanghai
(WMO index: 58362) were obtained from the National Climatic Data Center
(NCDC, https://www.ncdc.noaa.gov/isd, last access: 10 October 2018). The 10 s resolution
meteorological data were recorded by a shipborne meteorological station
during the cruise. The planetary boundary layer height (BLH) and 6 h
accumulated precipitation (TPP6) were extracted from NCEP's Global Data
Assimilation System Data (GDAS). The daily concentrations of gaseous
pollutants (SO2, CO, NO2 and O3) averaged from nine real-time
monitoring stations in Shanghai were obtained from the Shanghai
Environmental Monitoring Center (http://www.semc.gov.cn/aqi/home/DayData.aspx, last access: 3 May 2017). The farthest station,
Chuansha, is about 23.5 km away from Fudan site, and the daily concentrations
of gaseous pollutants varied consistently in the nine stations.
The 3 d air mass backward trajectories were calculated using a Hybrid
Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model
(http://ready.arl.noaa.gov/HYSPLIT.php, last access: 3 March 2018) with the starting height of 100 m.
The mass concentrations (mean values ± 1 standard deviation) of NH4+ and aminiums over Shanghai,
Huaniao Island and the YECS compared to other sites reported in the literature.
The values below the detection limits are indicated by < DL.
No.SiteSiteSampling periodParticleNH4+Aminium (ng m-3) Referencetypesize(µg m-3)MMAH+DMAH+TMDEAH+MEAH+TEAH+1Shanghai, ChinaurbanSpring (March–April 2013)PM2.56.0±3.46.4±6.14.8±2.38.4±8.4This study2Summer (July–August 2013)PM2.53.1±2.99.1±15.21.7±1.60.9±1.03Autumn (November 2013)PM2.56.8±4.515.5±13.42.8±2.912.7±12.24WinterPM2.513.7±9.827.3±29.07.3±6.235.2±45.6(December 2013–January 2014)5Shanghai, ChinaurbanJuly–August 2013PM1.82.5±1.38.9±6.115.7±7.938.8±17.011.5±17.4Tao et al. (2016)6PM102.6±1.39.9±6.920.1±10.747.0±19.915.7±26.47Shanghai, ChinaurbanJanuary 2013PM2.52.40.2Huang et al. (2016)8July–August 2013PM2.53.90.39Yangzhou, ChinaurbanNovember 2015–April 2016PM2.54.9±1.94.3±2.415.4±8.1Shen et al. (2017)10Nanjing, ChinaurbanApril–May 2016PM2.57.64.221.711August 2014PM1.87.2±4.118.0±11.736.4±18.612Xi'an, ChinaurbanJuly 2008–August 2009PM2.514.4±9.63.3±2.4Ho et al. (2015)13Guangzhou, ChinaurbanSeptember–October 2014PM0.954.3±1.141.8±11.414.5±3.23.7±0.93.2±0.4Liu et al. (2017)14PM35.1±1.450.4±13.717.7±3.64.8±1.44.0±0.515PM105.2±1.451.8±13.919.0±3.85.4±1.64.2±0.616Tampa Bay, Florida, USAurbanJuly–September 2005PM2.51.4±1.231.6±28.3Calderón et al. (2007)17A traffic site, Milan,ItalyurbanOctober 2013TSP4.2±2.990±20360±20Perrone et al. (2016)18A limited traffic site, Milan, ItalyurbanOctober 2013TSP4.0±3.0100±10420±10019Qingdao, Chinasemi-urbanMay 2013,PM0.056-106.35.8Xie et al. (2018)November–December 2013,November–December 201520Resort beach site in Qingdao, Chinacoastal, ruralAugust 2016PM0.056-1028.5±23.09.0±6.621Egbert, Toronto, Canadaagricultural and semi-forestedOctober 2010PM2.50.1±0.21±0.6VandenBoer et al. (2012)22Hyytiälä, southern Finlandboreal forestMarch 2015PM100.4±0.16.81.51.1Hemmilä et al. (2018)23April 2015PM100.1±0.12.93.10.724July 2015PM100.1±0.13.08.4±4.91.8±1.40.425Nanling, Guangdong, ChinaforestOctober 2016PM2.50.9±0.68.8±7.82.4±3.21.1±1.8Liu et al. (2018a)26May–June 20171.8±1.611.9±9.85.0±2.21.7±1.7
Continued.
No.SiteSiteSampling periodParticleNH4+Aminium (ng m-3) Referencetypesize(µg m-3)MMAH+DMAH+TMDEAH+MEAH+TEAH+27Brent, Alabama, USAforest1 June–15 July 2013submicron0.52148∗You et al. (2014)28Huaniao Island, ChinamarineAugust 2016PM2.50.7±0.44.0±0.68.7±3.7< DLThis study29November–December 2016PM1.81.9±1.510.7±9.36.0±6.8< DL30PM102.1±1.815.1±12.48.4±8.8< DL31March 2017PM1.82.0±1.26.8±4.62.7±1.8< DL32PM102.3±1.411.4±11.63.1±2.2< DL33June–July 2017PM1.82.1±1.429.0±10.824.8±5.4< DL34PM102.2±1.632.2±11.027.5±5.7< DL35August–September 2017PM1.81.4±0.725.8±8.725.0±11.0< DL36PM101.5±0.827.4±9.126.3±11.6< DL37Yellow Sea and East China SeamarineMarch–April 2017PM1.82.8±2.011.9±9.014.6±12.9< DL38PM103.0±2.213.5±10.116.6±14.5< DL39Yellow Sea and the northwestern PacificmarineApril 2015PM0.056-1012.9±10.613.2±13.8Xie et al. (2018)40East China SeamarineJanuary 2016PM0.056-1030.8±9.712.0±6.641Yellow Sea andmarineAugust 2015,PM0.056-1033.319.4Bohai SeaJune–July 201642Southern Yellow SeamarineNovember 2013PM0.056-1018.9±16.631.8±19.243Yellow Sea and Bohai SeamarineMay 2012PM11202±170432±426Hu et al. (2015)44Southern Yellow SeamarineNovember 2012PM1013.3±4.630.0±12.6Yu et al. (2016)45Northern Yellow Sea and Bohai SeamarineNovember 2012PM10–15.0±6.646Arabian SeamarineAugust–October 1994PM0.90.043.22.10.3Gibb et al. (1999)47November–December 1994PM0.90.13.711.10.548Mace Head, IrelandmarineJanuary–December 2006PM14.7±6.07.6±9.4Facchini et al. (2008)49Irish West CoastmarineJune–July 2006PM114.7±14.314.3±8.750São Vicente, CabomarineMay–June,PM0.14-0.420.10.10.40.2Müller et al. (2009)VerdeDecember 200751Off the Central Coast of California, USAmarineJuly 2007PM122Sorooshian et al. (2009)52Eastern Mediterranean, Greecemarine2005–2006PM19.2±36.8< DLViolaki and Mihalopoulos (2010)
Results and discussionSeasonal and spatial variations in aminium concentrations
The mean concentrations of NH4+ and aminiums in each campaign of
this study and reported in the literature were listed in Table 2. It should be
noted that TEAH+ concentrations over Huaniao Island and the YECS were
mostly below the detection limits (< DL). For other aminiums and
TEAH+ over Shanghai, the number of samples below detection limits was
generally less than 30 %. These undetectable concentrations were
considered to be zero for the calculation of means and standard deviations.
Three aminiums, DMAH+, TMDEAH+ and TEAH+, were commonly
detected in the aerosol samples collected from Shanghai. The most abundant
aminiums were DMAH+ and TEAH+, with annual means of 15.6 and
16.0 ng m-3, respectively. By comparison, the average TMDEAH+
concentration (4.4 ng m-3) was significantly lower. All three aminiums
showed the highest concentrations in winter and the lowest levels in spring
(DMAH+) and summer (TMDEAH+ and TEAH+), which generally
agreed with the seasonal trends of PM2.5 and NH4+
concentrations in Shanghai (Fig. 2). Specifically, the average TEAH+
reached 35.2 ng m-3 in winter in Shanghai, about 40 times as much as
that in summer. TEAH+ was mostly below the detection limit in the
aerosols collected over Huaniao Island and the YECS, suggesting its dominant
land sources and negligible marine contribution. By contrast, the average
DMAH+ and TMDEAH+ concentrations (14.0 and 13.2 ng m-3)
over Huaniao Island were close to and significantly higher than those over
Shanghai, respectively. Similarly high concentrations of DMAH+ and
TMDEAH+ (11.9 and 14.6 ng m-3) were also observed over the YECS
(Fig. 2 and Table 2), suggesting that the two aminiums might have notable
marine sources. Accordingly, both species reached the highest levels during
the summer campaigns in 2017 on Huaniao Island, consistent with the highest
primary productivity in the coastal ECS and prevailing winds from the ocean
in summer. As a major component of fine particles over eastern China with
similar chemical properties to aminiums, NH4+ was mainly from
terrestrial sources and its concentrations over Huaniao Island and YECS were
much lower than those over Shanghai (Fig. 2).
Our measurement of DMAH+ in Shanghai was comparable to those previously
reported from the urban sites but generally higher than those measured in
the forest areas of Toronto (VandenBoer et al., 2012), Hyytiälä
(Hemmilä et al., 2018) and Guangdong (Liu et al., 2018a). This implies
that anthropogenic activities may be crucial sources of DMAH+ in the
urban atmosphere. The TMDEAH+ concentrations in our study were much
lower than those reported by Tao et al. (2016) in Shanghai. Their sampling
location was close to the residential areas and could be
influenced by local sources, such as human excreta emissions (Zhou et al.,
2018). The aerosol TEAH+ concentrations in China were reported in our
study for the first time and could not be compared to previous work.
According to previous measurement results for gaseous amines in the same
site from 25 July to 25 August in 2015, the average mass concentrations of
C2, C3 plus C4 and C6 amines were 80.4, 53.1 and 15.8 ng m-3,
respectively (Yao et al., 2016). The order of concentrations was consistent
with that of the corresponding aerosol aminiums in the summer of 2013, which
was DMAH+> TMDEAH+> TEAH+ (9.1, 1.7
and 0.9 ng m-3, respectively) in this study. Based on these
concentrations, the ratios of each amine vs. aminium were roughly calculated
and C2 amines / DMAH+, (C3 plus C4 amines) / TMDEAH+ and
C6 amines / TEAH+ were 8.8, 30.1 and 17.9, respectively. These values
were comparable to the ratio of total amines to total aminiums (14.9) over a
mountain site in southern China (Liu et al., 2018a). Except for the three
aminiums commonly detected in this study, MMAH+ and MEAH+ (Liu et
al., 2018a; Ho et al., 2015; Shen et al., 2017) were other abundant aminiums
detected in the urban site.
Aerosols were collected using a MOUDI over Huaniao Island and the YECS.
Aminiums in PM1.8 of the MOUDI samples were compared to those of
PM2.5, since MOUDI does not have the 50 % cutoff diameter of 2.5 µm and aminiums in PM1.8 accounted for over 60 % of the concentrations over
the whole size range of aerosols. Our measurements of aminiums over Huaniao
Island and the YECS were comparable to those previously observed over the
seas off the eastern coast of China (Hu et al., 2015; Yu et al., 2016; Xie et al., 2018), but
they were apparently higher than many other oceanic regions, such as the Arabian
Sea (Gibb et al., 1999) and Cabo Verde (Müller et al., 2009). The high
aminiums over the YECS were probably associated with the severe air
pollution in eastern China and the high ocean productivity in
nearby marginal seas.
The mass concentrations of PM2.5, fine-particle
NH4+, and three aminiums (TEAH+, DMAH+ and TMDEAH+)
in different campaigns in Shanghai (SH), Huaniao Island (HNI) and the Yellow
and East China seas (YECS). The columns and error bars represent average
concentrations and standard deviations, respectively. The orange horizontal
lines represent the annual average concentrations of aminiums in SH and HNI.
(a) Relationships between concentrations of aminiums and
boundary layer height (BLH) over Shanghai in 2013. (b) Relationships between mass ratios of aminiums and NH4+ to
PM2.5 and temperature over Shanghai in 2013.(c) Relationships
between mass ratios of aminiums to NH4+ and O3 concentrations over Shanghai during the summer of 2013.
The concentrations of PM2.5, NH4+ and three aminiums sampled
in Shanghai in 2013 dropped significantly when the BLH increased from 200
to 500 m and then slowly decreased with the further increase in BLH (Figs. 3a
and S1), due to the enhanced ventilation. Specifically, the
concentrations of DMAH+, TMDEAH+ and TEAH+ (58.4, 13.9 and
80.5 ng m-3) in Shanghai reached its maximum, along with PM2.5 (447 µg m-3), during the severe haze event between 30 November and 8 December
2013, when the average BLH and wind speed were 298 m and 1.35 m s-1,
respectively (Fig. S2 in the Supplement). By comparison, the average concentrations of
DMAH+, TMDEAH+ and TEAH+ (8.9, 4.0 and 10.1 ng m-3) were
much lower prior to the haze event (on 26–29 November 2018) associated with the
higher BLH (636.4 m) and wind speed (2.73 m s-1). Thus, the generally
stagnant meteorology in winter (Liu et al., 2013) could cause a substantial
accumulation of aerosol aminiums and lead to the seasonal variation in
aminiums in Shanghai.
Temperature
To eliminate the synchronous change of aminiums and NH4+ with
PM2.5, the mass ratios of aminiums to PM2.5
(aminiums /PM2.5) and NH4+ to PM2.5
(NH4+/PM2.5) were applied for analysis. These ratios were
found to be negatively correlated with air temperature in Shanghai (Fig. 3b). Similar to NH4+, aminiums combined with NO3-,
Cl- and organic acids are semi-volatile and can dissociate in the
atmosphere (Tao and Murphy, 2018). Thus, the negative correlations may be
explained by the movement of gas-particle partitioning equilibrium to the
gas phase at higher temperatures (Ge et al., 2011a). This is consistent with
the previous observation that the proportion of particles containing
aminiums in the urban area of Shanghai was much higher in winter (23.4 %)
than in summer (4.4 %) (Huang et al., 2012). The seasonal variation
in temperature may also lead to the change of concentrations of aerosol
aminiums. It should be pointed out that environmental variables like BLH and
temperature are constantly changing with time and their impacts on aminium
concentrations may vary within the sampling duration (24 or 48 h).
However, these variables must be averaged over the same time interval as
aminium concentrations. This analysis may eliminate the instant discordance
and improve the correlations between environmental variables and aminiums or
aminiums /PM2.5, and the results could explain the seasonal
variation in aminiums well.
Time series of meteorological parameters and the
concentrations of aminiums and NH4+ during the 2017 spring cruise. The time range spanned by the column of each aminium concentration corresponds
to the sampling time.
Oxidizing capacity
As gaseous amines can be oxidized by oxidants such as ⚫OH,
O3 and NO3⚫ in the atmosphere before partitioning into
the particulate phase (Ge et al., 2011b; Nielsen et al., 2012; Yu and Luo,
2014), aminium concentrations in aerosols may decrease with enhanced
atmospheric oxidizing capacity. Ozone concentration can represent oxidizing
capacity of the lower atmosphere (Thompson, 1992). Here the relationship
between aminium /NH4+ ratios and O3 was examined because the
formation of particulate aminiums and NH4+ were both
temperature-dependent and using their ratios could avoid the temperature
effect to some extent. Besides, the residence time of NH3 in the
atmosphere due to the oxidation reaction is about 72.3 d (Ge et al.,
2011b), and therefore NH4+ concentrations in aerosols should not
be affected by O3. Negative correlations were found between
aminiums /NH4+ and O3 concentrations in Shanghai during the
summer of 2013 (Fig. 3c). In other seasons, the correlations were not
obvious, especially in winter when O3 concentrations were the lowest
and neither of the aminiums /NH4+ were correlated with O3 (Fig. S3). In general, atmospheric oxidizing capacity is the strongest in summer
(Logan, 1985; Liu et al., 2010), and the results verified that high
oxidizing capacity in summer may reduce the formation of particulate
aminiums by oxidizing gaseous amines. It was consistent with the diurnal
pattern of gaseous amines with the lowest values at noon and the negative
correlations between the concentrations of amines and O3 observed in
Shanghai during the summer of 2015 (Yao et al., 2016). It should be noted
that there was no significant variation in temperature and little rainfall
during the sampling periods in the summer of 2013. In other seasons, due to
the relatively weak photochemistry and more complex sources and meteorology,
other factors except oxidizing capacity played more important roles in
affecting aerosol aminiums.
Size distributions of aminiums during different
campaigns: (a–b) in the autumn of 2016 on Huaniao Island,
(c–d) in early summer 2017 on Huaniao Island, (e–f) in late summer 2017 on Huaniao Island, and (g–h) during the 2017 spring
cruise over the Yellow and East China seas.
Relative humidity and fog processing
In the spring of 2017 over the YECS, although the sample of 4–5 April was
influenced by high Chl a concentrations and low BLH, the concentrations of
DMAH+ and TMDEAH+ (13.3 and 17.4 ng m-3) were about half of
those on 7–9 April (Fig. 4). This was probably due to the intense fog event
that occurred on 7–9 April with relative humidity >90 %, which could
enhance the gas-to-particle partitioning of amines. The enhancement of TMA
gas to particles by cloud and fog processing has been observed in both field
and laboratory simulations (Rehbein et al., 2011). It was also found that
the number fraction of TMA-containing particles dramatically increased from
∼7 % on clear days to ∼35 % on foggy days
and that number-based size distribution of TMA-containing particles shifted
towards larger mode, peaking at the droplet mode (0.5–1.2 µm) in
Guangzhou (Zhang et al., 2012). The investigation over the Yellow and Bohai
seas in the summer of 2015 found significantly positive correlations between
the concentrations of DMAH+ and TMAH+ and relative humidity (Yu et
al., 2016). Therefore, fog and high relative humidity (RH) are also
favorable conditions for gas-to-particle conversion of amines.
The α values of NH4+,
nss-SO42- and aminiums in different campaigns. The diameter of the
circle is proportional to the concentration and the diamond-shaped symbol
represents the average value of α for each campaign. It should be
noted that the bottom of column is the line of α=1.
Size distributions and formation pathways of aerosol aminiums
The aminiums were mainly distributed in fine aerosols with diameter less
than 1.8 µm, and the mass percentages of DMAH+ and TMDEAH+ in
the coarse mode were around 36 % in the autumn of 2016 on Huaniao Island
and less than 15 % in all other campaigns on Huaniao Island and over the
YECS (Fig. 5a–d). This is consistent with the previous reports that
>70 % of aminiums were distributed in fine particles over
Shanghai during the summer of 2013 (Tao et al., 2016) and over the western
North Pacific and its marginal seas (Xie et al., 2018). The aminiums mostly
demonstrated a bimodal distribution in the autumn and early summer campaigns
on Huaniao Island with peaks at 0.18–0.32 µm (condensation mode) and
0.56–1.0 µm (droplet mode). This is similar to the size distributions
of DMAH+ and TMDEAH+ observed in Shanghai (Tao et al., 2016) and
to NH4+ and non-sea salt (nss-SO42-) in all campaigns
over Huaniao Island and the YECS (Figs. S4–S5). The size distribution suggests
that the gas-to-particle condensation (condensation mode) and cloud
processing (droplet mode) seem to be major mechanisms for the formation of
aminiums and other secondary species NH4+ and nss-SO42-.
Correlation coefficient matrix among the concentrations
of PM2.5 components and gaseous pollutants over Shanghai in 2013.
In order to compare the contributions between condensation and cloud
processing to the formation of specific species, the ratio of its
concentrations in droplet mode (0.56–1.0 µm) to those in condensation mode
(0.18–0.32 µm) was calculated (denoted as α). It could be seen
that the α values of NH4+ and nss-SO42- were
significantly greater than 1, especially in the case of high concentrations,
indicating that the cloud processing probably determined the concentrations
of these species (Fig. 6). In contrast, aminiums had α values around
1, suggesting that condensation and cloud processing might be equally
important to the formation of aminiums.
The spatial distribution of aminiums over the YECS in the
spring of 2017.The
light blue, pink and red lines represent 72 h backward trajectories
corresponding to sample sets collected on 7–9, 9–11 and 14 April,
respectively.
In late summer on Huaniao Island and the spring cruise over the YECS, when
air masses were mainly from oceanic regions (see Sect. 3.4.3), the aminiums
generally exhibited a unimodal distribution with one wide peak at 0.18–1.0 µm due to the increased concentrations at 0.32–0.56 µm (Fig. 5e–h). The concentrations of NH4+ and nss-SO42- also
showed a significant elevation in the size range of 0.32–0.56 µm
during these periods. The deviation of MOUDI cutoff diameters during the
sampling could be ruled out because the concentrations of particulate matter
always presented a trimodal distribution with peaks at 0.18–0.32,
0.56–1.8 and 3.2–10 µm. The unimodal distributions of
aminiums with the peak at 0.18–1.0 µm have been widely reported over
the seas off the eastern coast of China (Hu et al., 2015; Yu et al., 2016; Xie et al., 2018).
This suggests that the formation mechanisms of aerosol aminiums over the
ocean may be different from those over the land. It was indicated that the
high concentration and unique size distribution of TMAH+ observed over
the oligotrophic western North Pacific were mainly attributed to the primary
TMAH+ in sea-spray aerosols (Hu et al., 2018). In addition, some
studies have demonstrated that artificially generated sea spray aerosols and
actual primary marine aerosol both contained amines or aminiums (Bates et al.,
2012; Frossard et al., 2014; Dall'Osto et al., 2019). Thus, we speculate that
the elevated concentrations of aminiums at 0.32–0.56 µm over the seas off the eastern coast China may be also associated with the increased concentration
of sea-spray aerosols that contain substantial primary aminiums. On the other
hand, the heterogeneous formation of secondary aminiums on the surface of
sea spray aerosols cannot be ruled out (Yu et al., 2016).
(a) Size distributions of NO3- over the YECS in
the spring of 2017. (b) Correlations between concentrations of
aminiums and NH4+ for the samples mainly influenced by marine air
masses. (c) Correlations between concentrations of aminiums and
NH4+ for the samples predominantly influenced by terrestrial
transport.
Correlations between aminiums and NH4+
concentrations over Huaniao Island for each campaign: (a) in the
summer of 2016, (b) in the autumn of 2016, (c) in early
summer 2017, and (d) in late summer 2017.
Sources of aerosol aminiumsAnthropogenic sources on the land
Correlation analysis was carried out between aminiums, other PM2.5 components and gaseous pollutants measured in Shanghai (Fig. 7). It can be
seen that the secondary inorganic components SO42-, NO3-
and NH4+ (SNA), PM2.5, and DMAH+ were significantly
correlated with each other with the correlation coefficients above 0.6. This
suggests that anthropogenic sources may have a great contribution to the
atmospheric DMA in Shanghai, which is consistent with previous findings in
Nanjing (Zheng et al., 2015). Considering the unique role of DMA in new
particle formation (Almeida et al., 2013), our results reinforce that the
frequent new particle formation events observed in extremely polluted
Chinese cities are indeed, at least in part, due to amines (Yao et al.,
2018). The correlations between TEAH+ and SNA were relatively weak, but
TEAH+ was found to be significantly correlated with the components
mainly from industrial sources (represented by the high concentrations of K,
Mn, Cd, Pb, Zn and Cl-) (Tian et al., 2015; Liu et al., 2018b),
indicating that industrial emissions could be an important source of triethylamine.
It was consistent with the observation result in a suburban site, where
gaseous C4 to C6 amines had some abrupt and frequent increases during the night,
and may be caused by some local emissions (You et al., 2014). Compared to
the DMAH+ and TEAH+, TMDEAH+ showed much weaker correlation
with the anthropogenically derived components. Weak correlations were also
found between all the aminiums and V, Ni, Al, Mg, Ca and Fe, suggesting that
ship emissions (traced by V and Ni) and soil dust (represented by Al, Ca and
Fe) were not the main sources of aminiums in PM2.5 over Shanghai.
The 72 h backward trajectories starting from Huaniao
Island and the average Chl a concentration retrieved and combined
from Aqua-MODIS and Terra-MODIS during the sampling period. Each sample during
the summer of 2016 corresponds to one trajectory with a starting time in the
middle of sampling period. Each sample set during the autumn of 2016 and the
summer of 2017 corresponds to three trajectories and the starting times are
taken at equal intervals in the sampling period.
Marine biogenic source
As discussed in Sect. 3.1, the relatively high concentrations of DMAH+
and TMDEAH+ over Huaniao Island and the YECS implied that the marine
sources contributed substantially to these two aminiums. Accordingly, a
spatial variation in aminium concentrations was observed over the YECS
during the spring cruise. The concentrations of DMAH+ and TMDEAH+
increased by a factor of 3–5 in the southern ECS (average 24.4 and 40.3 ng m-3 for the samples of 7–11 April, respectively) compared to the YS and
northern ECS (average 7.0 and 8.4 ng m-3 for the samples of 27 March–5 April, respectively) (Fig. 8). This is consistent with the noticeable
difference of Chl a concentrations between the southern and northern YECS
(2.3 times higher in the southern YECS than that in northern YECS, unpublished
data). Furthermore, the highest TMDEAH+ and lowest NH4+
concentrations observed on 7–11 April corresponded to the air mass back
trajectories originating from the ocean, suggesting that the metabolic
activities of surface plankton in highly productive seas could be a strong
source of amines, as previously reported (Facchini et al., 2008; Müller
et al., 2009; Sorooshian et al., 2009; Hu et al., 2015). In contrast, the
high concentrations of aminiums observed on 14 April near Qingdao were
affected by the air masses transported from eastern China (Fig. 8) and
thereby contributed to mainly by terrestrial sources.
Correlations between DMAH+ and TMDEAH+ for
each campaign over Huaniao Island and the YECS.
Fine-mode NH4NO3 could decompose during its transport from the
land to the ocean, and the released HNO3 gas would react with dust and
sea salt aerosols to form coarse-mode NO3-. Therefore, negative
correlations were observed between the concentrations of fine-mode
NO3- and alkaline species (Na++Ca2+) over East
Asia (Bian et al., 2014; Uno et al., 2017). Since only one dust event was
encountered on 12–13 April during the cruise (unpublished data), the
coarse-mode NO3- in this study should be mostly formed by
heterogeneous reaction with sea salts. Therefore, the importance of
terrestrial transport to marine aerosols could be roughly estimated by the
percentage of NO3- in the fine mode. For aerosols collected on
29–31 March and 4–5, 7–9, and 9–11 April, over two-thirds of concentrations of
NO3- were in the coarse mode (>1.8µm, Fig. 9a).
These samples should be less affected by the terrestrial air masses
(referred to hereafter as Category 1) compared to other samples (referred to hereafter as Category 2),
and the analysis was consistent with the forward directions of air mass
trajectories (Fig. S6). Aminiums were negatively correlated with
NH4+ for Category 1 samples, suggesting that aminiums were probably
dominated by marine biogenic sources, whereas NH4+ was influenced
by terrestrial transport (Fig. 9b). For Category 2 samples, a positive
correlation was found between aminiums and NH4+, indicating that
terrestrial sources could contribute significantly to aminiums over the YECS
in these cases (Fig. 9c).
Source contributions to aminiums over the coastal sea
Huaniao Island is located on the front line of terrestrial transport to the
ECS and influenced by the air masses from the land or ocean, depending on the
seasonal variation in prevailing winds. Significantly positive correlations
were found between the concentrations of aminiums and NH4+ in the
autumn but not in the summer of 2016 or in late summer 2017 (Fig. 10).
Accordingly, the majority of backward trajectories pointed towards northern
China in autumn, whereas air masses predominantly originate from the ECS in
summer (Fig. 11). Meanwhile, NO3- demonstrated a trimodal
distribution with three peaks at 0.18–0.32 µm (condensation mode),
0.56–1.0 µm (droplet mode) and 3.2–5.6 µm (coarse mode) in
autumn but only one peak at 3.2–5.6 µm in late summer 2017 (Fig. S7). This implies that terrestrial transport could be a dominant source for
aminiums over the coastal ECS in autumn, whereas marine sources were dominant
in late summer. In early summer 2017, the mass ratios of aminiums to
NH4+ were significantly lower on 26–28 June than those on other
days (Fig. S8), corresponding to different origins and properties of the air
masses. Removing the data measured on 26–28 June, we found a significantly
positive correlation between the concentrations of DMAH+ and
NH4+ but not between TMDEAH+ and NH4+. This
suggests that DMAH+ and TMDEAH+ may be predominantly derived from
terrestrial and marine sources, respectively.
Calculated terrestrial and marine source contributions to
aerosol aminiums over Huaniao Island (mean; minimum–maximum).
Good positive correlations were generally found between the concentrations
of TMDEAH+ and DMAH+ over Huaniao Island and the YECS, and the
slope for autumn samples dominated by terrestrial sources was significantly
lower than those influenced primarily by marine air masses (e.g., late summer
on Huaniao Island and spring over the YECS, Fig. 12). The highest slope of
TMDEAH+ vs. DMAH+ (1.98) occurred in the summer of 2016, which was
also mainly affected by marine sources. Therefore, it is speculated that
aminiums derived from marine biogenic source might have significantly higher
TMDEAH+ to DMAH+ ratios than those from terrestrial sources.
Similarly, Hu et al. (2015) observed a significant correlation between the
TMDEAH+ and DMAH+ concentrations over the Yellow Sea with a
slope of 1.27–2.49. In early summer 2017, the weak correlation between
the DMAH+ and TMDEAH+ and very low slope (0.29) suggested the
mixing of terrestrial and marine influence on aminiums over Huaniao Island
during that period as discussed above.
Dimethylsulfide (DMS) produced in seawater by the metabolism of plankton
will be released into the atmosphere, and SO2, MSA, SO42- and
other products can be formed through a series of oxidation reactions
(Saltzman et al., 1985; Charlson et al., 1987; Faloona, 2009; Barnes et al.,
2006). MSA is often used as a tracer of marine biogenic source to calculate
the marine biogenic contribution to nss-SO42- (Yang et al., 2009, 2015). Therefore, the mass ratio of MSA to nss-SO42-
(MSA / nss-SO42-) can be used to indicate the contribution of marine
sources to relevant aerosol components. A significant linear relationship
was found between aminium /NH4+ and MSA / nss-SO42- for the
samples collected in the autumn of 2016 and summer of 2017 over Huaniao
Island (Fig. 13). The value of aminium /NH4+ increased with the
increasing contribution of marine sources to the aerosol aminium. When the
marine biogenic source contribution is 0, the corresponding
aminium /NH4+ values (b in Eq. 1) represent the average ratios
that are completely contributed by terrestrial sources. By multiplying the ratios by
NH4+ concentrations, the aerosol aminiums contributed by
terrestrial sources can be calculated (Eq. 2). Therefore, the
contributions of terrestrial and marine sources to aerosol aminiums can be
quantitatively estimated.
1aminium/NH4+terrestrial=k×MSA/nss-SO42-terrestrial+b,2aminium=aminium/NH4+terrestrial×NH4++aminiummarine,
where k and b are the slope and intercept of the linear fitting equation of
aminium/NH4+ and MSA/nss-SO42-, respectively (Fig. 13).
Correlations between aminium /NH4+ and
MSA / nss-SO42- over Huaniao Island during autumn 2016 and summer 2017.
Although most of MSA comes from marine sources, the terrestrial sources may
also make up a certain contribution (Yuan et al., 2004). Therefore,
MSA / nss-SO42-= 0 was not used as the end member value for
calculating the terrestrial contribution. We have simultaneously measured
MSA and nss-SO42- in a total of 64 total suspended particle (TSP)
samples collected in the autumn of 2016 and the summer of 2017. The
retention percentage of air mass over the land (RL) was calculated for
each sample based on 3 d backward trajectories (see Figure S9 and
supplementary text for more information). Samples with the largest 10 %
RL values (n=7, RL>74 %) were considered to be
terrestrially dominant with an average MSA / nss-SO42- (±1
standard deviation) of 0.0021±0.0013. Therefore, this value was
regarded as the end member value of terrestrial MSA / nss-SO42- in
these seasons. Substituting it into the previous fitting equation, the
values of DMAH+/NH4+terrestrial and TMDEAH+/NH4+terrestrial were 0.0068 (0.0038–0.0105) and
0.0034 (0.00005–0.0076), respectively. Then the average contributions of
terrestrial and marine sources to the two aminiums in each campaign were
calculated and shown in Table 3. It can be seen that the average terrestrial
contributions to DMAH+ and TMDEAH+ in aerosols were both more than
60 % in autumn, higher than those in summer. The contributions of marine
sources during late summer 2017 (63.0 % for DMAH+ and 78.3 % for
TMDEAH+) were higher than those in early summer (53.3 % for
DMAH+ and 74.2 % for TMDEAH+), which was consistent with
previous hypothesis. Furthermore, the contribution of marine sources was
greater to TMDEAH+ than to DMAH+ in all campaigns, which
corresponded to the higher ratio of TMDEAH+/ DMAH+ in the samples
influenced primarily by marine air masses (Fig. 12). It should be pointed
out that aminium /NH4+ ratios could vary with the chemistry of
aerosols due to slightly different gas-to-particle partitioning of the
amines and NH3 (Chan and Chan, 2013; Pankow, 2015; Xie et al., 2018)
and marine aminiums may also partially originate from primary sources, as
discussed above. Therefore, our discussion is constrained in the source
analysis of aerosol aminiums but not gaseous or total amines (gaseous
amines + aerosol aminiums). Although NH4+ was mainly derived
from the land, marine sources may also have made a certain contribution (Altieri
et al., 2014; Paulot et al., 2015). This was neglected in our calculation
and might lead to the overestimate of terrestrial contributions to aminiums.
Besides, the relatively small number of data points used in the fitting (25
points) and the treatment of aminium/NH4+terrestrial as a fixed value ignoring its variation could cause
uncertainty in the results. Nonetheless, our method is the first attempt to
calculate the contributions of marine biogenic and terrestrial sources to
aerosol aminiums over the coastal sea, which will provide an insight of
sources and roles of amines in the atmosphere.
Conclusions
Amines in the atmosphere play an important role in new particle formation
and subsequent particle growth, and studying aerosol aminiums can provide
insight into the sources, reaction pathways and environmental effects of
amines. An integrated observation was conducted on aerosol aminiums
(DMAH+, TMDEAH+ and TEAH+) in a coastal city
(Shanghai), a nearby island (Huaniao) and the surrounding marginal seas (the YECS). All
three aminiums exhibited significant seasonal variation in Shanghai, with
their highest concentrations in winter, which was consistent with relatively
severe air pollution associated with the winter monsoon (continental winds)
and the lowest BLH and temperature in this season. Atmospheric oxidizing
capacity and relative humidity may also influence the concentrations of
aerosol aminiums to some extent by oxidizing gaseous amines and enhancing
gas-particle partitioning, respectively. By comparing the ocean sites to
Shanghai, similar DMAH+ concentrations and 3-fold higher
TMDEAH+ concentrations were observed, suggesting that these two aminiums may have
significant marine sources. In contrast, TEAH+ was abundant in Shanghai
but was below the detection limit over Huaniao Island and the YECS,
implying its terrestrial origin.
Aminiums influenced substantially by terrestrial transport showed a bimodal
distribution with two peaks at 0.18–0.32 µm (condensation mode) and
0.56–1.0 µm (droplet mode), suggesting that the gas-to-particle
condensation and cloud processing were main formation pathways for aerosol
aminiums. Nonetheless, aminiums demonstrated a unimodal distribution with a
wide peak at 0.18–1.0 µm over the YECS and in late summer on Huaniao
Island, and the elevated concentration at 0.32–0.56 µm might be
related to sea-spray aerosols that either contain primary aminiums or
provide a surface for heterogeneous reactions to form secondary aminiums. This
indicates that aminiums in marine aerosols may undergo different formation
pathways from those on the land.
We distinguished the contributions of terrestrial and marine sources to
aerosol aminiums for the first time by taking the mass ratio of MSA to
nss-SO42- as an indicator of marine biogenic sources. In the
autumn of 2016, the contributions of terrestrial sources to aminiums over
Huaniao Island were estimated to be more than 60 %. By contrast, marine
biogenic sources dominated aminium concentrations especially for
TMDEAH+ (∼80 %) in the summer of 2017. Our results indicated
that marine biogenic emission of amines could not be ignored on the eastern
coast of China, especially in summer. Therefore, it is necessary to add this
source into the emission inventory of amines and recent modeling of amines
over eastern China without a marine source (Mao et al., 2018) may result in
significant deviations. Besides, the role of amines in new particle
formation over the open ocean is likely to be more important, due to much
lower pollution compared to the coastal area, which should be
further studied.
Data availability
Data are available from the corresponding author on request
(yingchen@fudan.edu.cn).
The supplement related to this article is available online at: https://doi.org/10.5194/acp-19-10447-2019-supplement.
Author contributions
SZ, YC and CD conceived the study. SZ, YC and CD wrote the paper. SZ, HL
and JX collected the samples. SZ, TY and JX performed the measurements. All
authors contributed to the review of the manuscript.
Competing interests
The authors declare that they have no conflict of interest.
Acknowledgements
We gratefully acknowledge the NOAA Air Resources Laboratory (ARL)
for the provision of the HYSPLIT model used in this publication and the
National Climatic Data Center (NCDC) for the archived observed surface
meteorological data. The MODIS Chl a data were downloaded from NASA
OceanColor website (https://oceancolor.gsfc.nasa.gov/, last access: 8 February, 2018). We are sincerely
grateful to Huaniao Lighthouse, maintained by Shanghai Maritime Safety
Administration, for providing the long-term sampling site and the fisherman
Yueping Chen and his wife for their sampling assistance on Huaniao Island. We also
thank all of the sailors onboard R/V Dongfanghong II for their logistical support during
the cruise. Shengqian Zhou sincerely acknowledges Bo Wang, Xiaofei Qin,
Tianfeng Guo, Fanghui Wang and Yucheng Zhu for their assistance with field
and laboratory work. We thank two anonymous referees sincerely for their constructive comments.
Financial support
This research has been supported by the National Key Research and Development Program of China (grant no. 2016YFA0601304), the National Natural Science Foundation of China (grant no. 41775145), and the Fudan's Undergraduate Research Opportunities Program (grant no. 15100).
Review statement
This paper was edited by Alex Huffman and reviewed by two anonymous referees.
ReferencesAlmeida, J., Schobesberger, S., Kurtén, A., Ortega, I. K., Kupiainen-Maatta,
O., Praplan, A. P., Adamov, A., Amorim, A., Bianchi, F., Breitenlechner, M.,
David, A., Dommen, J., Donahue, N. M., Downard, A., Dunne, E., Duplissy, J.,
Ehrhart, S., Flagan, R. C., Franchin, A., Guida, R., Hakala, J., Hansel, A.,
Heinritzi, M., Henschel, H., Jokinen, T., Junninen, H., Kajos, M.,
Kangasluoma, J., Keskinen, H., Kupc, A., Kurtén, T., Kvashin, A. N.,
Laaksonen, A., Lehtipalo, K., Leiminger, M., Leppa, J., Loukonen, V.,
Makhmutov, V., Mathot, S., McGrath, M. J., Nieminen, T., Olenius, T.,
Onnela, A., Petaja, T., Riccobono, F., Riipinen, I., Rissanen, M., Rondo,
L., Ruuskanen, T., Santos, F. D., Sarnela, N., Schallhart, S., Schnitzhofer,
R., Seinfeld, J. H., Simon, M., Sipila, M., Stozhkov, Y., Stratmann, F.,
Tome, A., Trostl, J., Tsagkogeorgas, G., Vaattovaara, P., Viisanen, Y.,
Virtanen, A., Vrtala, A., Wagner, P. E., Weingartner, E., Wex, H.,
Williamson, C., Wimmer, D., Ye, P., Yli-Juuti, T., Carslaw, K. S., Kulmala,
M., Curtius, J., Baltensperger, U., Worsnop, D. R., Vehkamaki, H., and
Kirkby, J.: Molecular understanding of sulphuric acid-amine particle
nucleation in the atmosphere, Nature, 502, 359–363,
10.1038/nature12663, 2013.Altieri, K. E., Hastings, M. G., Peters, A. J., Oleynik, S., and Sigman, D.
M.: Isotopic evidence for a marine ammonium source in rainwater at Bermuda,
Global Biogeochem. Cy., 28, 1066–1080, 10.1002/2014GB004809,
2014.Barnes, I., Hjorth, J., and Mihalopoulos, N.: Dimethyl sulfide and dimethyl
sulfoxide and their oxidation in the atmosphere, Chem. Rev., 106, 940–975,
10.1021/cr020529+, 2006.Bates, T. S., Quinn, P. K., Frossard, A. A., Russell, L. M., Hakala, J.,
Petäjä, T., Kulmala, M., Covert, D. S., Cappa, C. D., Li, S. M.,
Hayden, K. L., Nuaaman, I., McLaren, R., Massoli, P., Canagaratna, M. R.,
Onasch, T. B., Sueper, D., Worsnop, D. R., and Keene, W. C.: Measurements of
ocean derived aerosol off the coast of California, J. Geophys. Res.-Atmos.,
117, D00V15, 10.1029/2012jd017588, 2012.Bian, Q., Huang, X. H. H., and Yu, J. Z.: One-year observations of size distribution characteristics of major aerosol constituents at a coastal receptor site in Hong Kong – Part 1: Inorganic ions and oxalate, Atmos. Chem. Phys., 14, 9013–9027, 10.5194/acp-14-9013-2014, 2014.Calderón, S. M., Poor, N. D., and Campbell, S. W.: Estimation of the
particle and gas scavenging contributions to wet deposition of organic
nitrogen, Atmos. Environ., 41, 4281–4290,
10.1016/j.atmosenv.2006.06.067, 2007.Chan, L. P. and Chan, C. K.: Role of the aerosol phase state in
ammonia/amines exchange reactions, Environ. Sci. Technol., 47, 5755–5762,
10.1021/es4004685, 2013.Charlson, R. J., Lovelock, J. E., Andreaei, M. O., and Warren, S. G.:
Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate,
Nature, 326, 655–661, 10.1038/326655a0, 1987.Dall'Osto, M., Airs, R., Beale, R., cree, c., fitzsimons, m., Beddows, D. C. S., Harrison, R. M., Ceburnis, D., O'Dowd, C., Rinaldi, M., Paglione, M., Nenes, A., Decesari, S., and Simo, R.: Simultaneous detection of alkylamines in the surface ocean and atmosphere of the Antarctic sympagic environment, ACS Earth Space Chem., 3, 854–862, 10.1021/acsearthspacechem.9b00028, 2019.Dawson, M. L., Perraud, V., Gomez, A., Arquero, K. D., Ezell, M. J., and Finlayson-Pitts, B. J.: Measurement of gas-phase ammonia and amines in air by collection onto an ion exchange resin and analysis by ion chromatography, Atmos. Meas. Tech., 7, 2733–2744, 10.5194/amt-7-2733-2014, 2014.Erupe, M. E., Viggiano, A. A., and Lee, S.-H.: The effect of trimethylamine on atmospheric nucleation involving H2SO4, Atmos. Chem. Phys., 11, 4767–4775, 10.5194/acp-11-4767-2011, 2011.Facchini, M. C., Decesari, S., Rinaldi, M., Carbone, C., Finessi, E.,
Mircea, M., Fuzzi, S., Moretti, F., Tagliavini, E., Ceburnis, D., and
O'Dowd, C. D.: Important source of marine secondary organic aerosol from
biogenic amines, Environ. Sci. Technol., 42, 9116–9121,
10.1021/es8018385, 2008.Faloona, I.: Sulfur processing in the marine atmospheric boundary layer: A
review and critical assessment of modeling uncertainties, Atmos. Environ.,
43, 2841–2854, 10.1016/j.atmosenv.2009.02.043, 2009.Frossard, A. A., Russell, L. M., Burrows, S. M., Elliott, S. M., Bates, T.
S., and Quinn, P. K.: Sources and composition of submicron organic mass in
marine aerosol particles, J. Geophys. Res.-Atmos., 119, 12977–13003,
10.1002/2014jd021913, 2014.Ge, X., Wexler, A. S., and Clegg, S. L.: Atmospheric amines – Part II,
Thermodynamic properties and gas/particle partitioning, Atmos. Environ., 45,
561–577, 10.1016/j.atmosenv.2010.10.013, 2011a.Ge, X., Wexler, A. S., and Clegg, S. L.: Atmospheric amines – Part I, A
review, Atmos. Environ., 45, 524–546,
10.1016/j.atmosenv.2010.10.012, 2011b.Gibb, S. W., Mantoura, R. F. C., and Liss, P. S.: Ocean-atmosphere exchange
and atmospheric speciation of ammonia and methylamines in the region of the
NW Arabian Sea, Global Biogeochem. Cy., 13, 161–178,
10.1029/98gb00743, 1999.Hemmilä, M., Hellén, H., Virkkula, A., Makkonen, U., Praplan, A. P., Kontkanen, J., Ahonen, L., Kulmala, M., and Hakola, H.: Amines in boreal forest air at SMEAR II station in Finland, Atmos. Chem. Phys., 18, 6367–6380, 10.5194/acp-18-6367-2018, 2018.Ho, K. F., Ho, S. S. H., Huang, R.-J., Liu, S. X., Cao, J.-J., Zhang, T.,
Chuang, H.-C., Chan, C. S., Hu, D., and Tian, L.: Characteristics of
water-soluble organic nitrogen in fine particulate matter in the continental
area of China, Atmos. Environ., 106, 252–261,
10.1016/j.atmosenv.2015.02.010, 2015.Hu, Q., Yu, P., Zhu, Y., Li, K., Gao, H., and Yao, X.: Concentration, Size
Distribution, and Formation of Trimethylaminium and Dimethylaminium Ions in
Atmospheric Particles over Marginal Seas of China, J. Atmos. Sci., 72,
3487–3498, 10.1175/jas-d-14-0393.1, 2015.
Hu, Q., Qu, K., Gao, H., Cui, Z., Gao, Y., and Yao, X.: Large increases in primary trimethylaminium and secondary dimethylaminium in atmospheric particles associated with cyclonic eddies in the northwest Pacific Ocean, J. Geophys. Res.-Atmos., 123, 12133–12146, 10.1029/2018jd028836, 2018.Huang, R.-J., Li, W.-B., Wang, Y.-R., Wang, Q. Y., Jia, W. T., Ho, K.-F., Cao, J. J., Wang, G. H., Chen, X., EI Haddad, I., Zhuang, Z. X., Wang, X. R., Prévôt, A. S. H., O'Dowd, C. D., and Hoffmann, T.: Determination of alkylamines in atmospheric aerosol particles: a comparison of gas chromatography-mass spectrometry and ion chromatography approaches, Atmos. Meas. Tech., 7, 2027–2035, 10.5194/amt-7-2027-2014, 2014.Huang, X., Deng, C., Zhuang, G., Lin, J., and Xiao, M.: Quantitative
analysis of aliphatic amines in urban aerosols based on online
derivatization and high performance liquid chromatography, Environ.
Sci.-Proc. Imp., 18, 796–801, 10.1039/c6em00197a, 2016.Huang, Y., Chen, H., Wang, L., Yang, X., and Chen, J.: Single particle
analysis of amines in ambient aerosol in Shanghai, Environ. Chem., 9, 202,
10.1071/en11145, 2012.Kupiainen, O., Ortega, I. K., Kurtén, T., and Vehkamäki, H.: Amine substitution into sulfuric acid – ammonia clusters, Atmos. Chem. Phys., 12, 3591–3599, 10.5194/acp-12-3591-2012, 2012.Kurtén, A., Jokinen, T., Simon, M., Sipila, M., Sarnela, N., Junninen, H.,
Adamov, A., Almeida, J., Amorim, A., Bianchi, F., Breitenlechner, M.,
Dommen, J., Donahue, N. M., Duplissy, J., Ehrhart, S., Flagan, R. C.,
Franchin, A., Hakala, J., Hansel, A., Heinritzi, M., Hutterli, M.,
Kangasluoma, J., Kirkby, J., Laaksonen, A., Lehtipalo, K., Leiminger, M.,
Makhmutov, V., Mathot, S., Onnela, A., Petaja, T., Praplan, A. P.,
Riccobono, F., Rissanen, M. P., Rondo, L., Schobesberger, S., Seinfeld, J.
H., Steiner, G., Tome, A., Trostl, J., Winkler, P. M., Williamson, C.,
Wimmer, D., Ye, P., Baltensperger, U., Carslaw, K. S., Kulmala, M., Worsnop,
D. R., and Curtius, J.: Neutral molecular cluster formation of sulfuric
acid-dimethylamine observed in real time under atmospheric conditions, P. Natl. Acad. Sci. USA, 111, 15019–15024,
10.1073/pnas.1404853111, 2014.Kürten, A., Bergen, A., Heinritzi, M., Leiminger, M., Lorenz, V., Piel, F., Simon, M., Sitals, R., Wagner, A. C., and Curtius, J.: Observation of new particle formation and measurement of sulfuric acid, ammonia, amines and highly oxidized organic molecules at a rural site in central Germany, Atmos. Chem. Phys., 16, 12793–12813, 10.5194/acp-16-12793-2016, 2016.Kurtén, T., Loukonen, V., Vehkamäki, H., and Kulmala, M.: Amines are likely to enhance neutral and ion-induced sulfuric acid-water nucleation in the atmosphere more effectively than ammonia, Atmos. Chem. Phys., 8, 4095–4103, 10.5194/acp-8-4095-2008, 2008.Liu, F., Bi, X., Zhang, G., Peng, L., Lian, X., Lu, H., Fu, Y., Wang, X.,
Peng, P., and Sheng, G.: Concentration, size distribution and dry
deposition of amines in atmospheric particles of urban Guangzhou, China,
Atmos. Environ., 171, 279–288,
10.1016/j.atmosenv.2017.10.016, 2017.Liu, F., Bi, X., Zhang, G., Lian, X., Fu, Y., Yang, Y., Lin, Q., Jiang, F.,
Wang, X., Peng, P., and Sheng, G.: Gas-to-particle partitioning of
atmospheric amines observed at a mountain site in southern China, Atmos.
Environ., 195, 1–11, 10.1016/j.atmosenv.2018.09.038, 2018a.Liu, X. G., Li, J., Qu, Y., Han, T., Hou, L., Gu, J., Chen, C., Yang, Y., Liu, X., Yang, T., Zhang, Y., Tian, H., and Hu, M.: Formation and evolution mechanism of regional haze: a case study in the megacity Beijing, China, Atmos. Chem. Phys., 13, 4501–4514, 10.5194/acp-13-4501-2013, 2013.Liu, X.-H., Zhang, Y., Cheng, S.-H., Xing, J., Zhang, Q., Streets, D. G.,
Jang, C., Wang, W.-X., and Hao, J.-M.: Understanding of regional air
pollution over China using CMAQ, part I performance evaluation and seasonal
variation, Atmos. Environ., 44, 2415–2426,
10.1016/j.atmosenv.2010.03.035, 2010.Liu, Y., Han, C., Liu, C., Ma, J., Ma, Q., and He, H.: Differences in the reactivity of ammonium salts with methylamine, Atmos. Chem. Phys., 12, 4855–4865, 10.5194/acp-12-4855-2012, 2012.Liu, Y., Fan, Q., Chen, X., Zhao, J., Ling, Z., Hong, Y., Li, W., Chen, X., Wang, M., and Wei, X.: Modeling the impact of chlorine emissions from coal combustion and prescribed waste incineration on tropospheric ozone formation in China, Atmos. Chem. Phys., 18, 2709–2724, 10.5194/acp-18-2709-2018, 2018b.Logan, J. A.: Tropospheric ozone: Seasonal behavior, trends, and
anthropogenic influence, J. Geophys. Res.-Atmos., 90, 10463–10482,
10.1029/JD090iD06p10463, 1985.Loukonen, V., Kurtén, T., Ortega, I. K., Vehkamäki, H., Pádua, A. A. H., Sellegri, K., and Kulmala, M.: Enhancing effect of dimethylamine in sulfuric acid nucleation in the presence of water – a computational study, Atmos. Chem. Phys., 10, 4961–4974, 10.5194/acp-10-4961-2010, 2010.Mao, J., Yu, F., Zhang, Y., An, J., Wang, L., Zheng, J., Yao, L., Luo, G., Ma, W., Yu, Q., Huang, C., Li, L., and Chen, L.: High-resolution modeling of gaseous methylamines over a polluted region in China: source-dependent emissions and implications of spatial variations, Atmos. Chem. Phys., 18, 7933–7950, 10.5194/acp-18-7933-2018, 2018.Müller, C., Iinuma, Y., Karstensen, J., van Pinxteren, D., Lehmann, S., Gnauk, T., and Herrmann, H.: Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands, Atmos. Chem. Phys., 9, 9587–9597, 10.5194/acp-9-9587-2009, 2009.Murphy, S. M., Sorooshian, A., Kroll, J. H., Ng, N. L., Chhabra, P., Tong, C., Surratt, J. D., Knipping, E., Flagan, R. C., and Seinfeld, J. H.: Secondary aerosol formation from atmospheric reactions of aliphatic amines, Atmos. Chem. Phys., 7, 2313–2337, 10.5194/acp-7-2313-2007, 2007.Nielsen, C. J., Herrmann, H., and Weller, C.: Atmospheric chemistry and
environmental impact of the use of amines in carbon capture and storage
(CCS), Chem. Soc. Rev., 41, 6684–6704, 10.1039/c2cs35059a,
2012.Olenius, T., Halonen, R., Kurtén, T., Henschel, H.,
Kupiainen-Määttä, O., Ortega, I. K., Jen, C. N., Vehkamäki,
H., and Riipinen, I.: New particle formation from sulfuric acid and amines:
Comparison of monomethylamine, dimethylamine, and trimethylamine, J.
Geophys. Res.-Atmos., 122, 7103–7118, 10.1002/2017jd026501,
2017.Paasonen, P., Olenius, T., Kupiainen, O., Kurtén, T., Petäjä, T., Birmili, W., Hamed, A., Hu, M., Huey, L. G., Plass-Duelmer, C., Smith, J. N., Wiedensohler, A., Loukonen, V., McGrath, M. J., Ortega, I. K., Laaksonen, A., Vehkamäki, H., Kerminen, V.-M., and Kulmala, M.: On the formation of sulphuric acid – amine clusters in varying atmospheric conditions and its influence on atmospheric new particle formation, Atmos. Chem. Phys., 12, 9113–9133, 10.5194/acp-12-9113-2012, 2012.Pankow, J. F.: Phase considerations in the gas/particle partitioning of
organic amines in the atmosphere, Atmos. Environ., 122, 448–453,
10.1016/j.atmosenv.2015.09.056, 2015.Paulot, F., Jacob, D. J., Johnson, M. T., Bell, T. G., Baker, A. R., Keene,
W. C., Lima, I. D., Doney, S. C., and Stock, C. A.: Global oceanic emission
of ammonia: Constraints from seawater and atmospheric observations, Global
Biogeochem. Cy., 29, 1165–1178, 10.1002/2015gb005106, 2015.Perrone, M. G., Zhou, J., Malandrino, M., Sangiorgi, G., Rizzi, C., Ferrero,
L., Dommen, J., and Bolzacchini, E.: PM chemical composition and oxidative
potential of the soluble fraction of particles at two sites in the urban
area of Milan, Northern Italy, Atmos. Environ., 128, 104–113,
10.1016/j.atmosenv.2015.12.040, 2016.Rehbein, P. J., Jeong, C. H., McGuire, M. L., Yao, X., Corbin, J. C., and
Evans, G. J.: Cloud and fog processing enhanced gas-to-particle partitioning
of trimethylamine, Environ. Sci. Technol., 45, 4346–4352,
10.1021/es1042113, 2011.Rinaldi, M., Decesari, S., Finessi, E., Giulianelli, L., Carbone, C., Fuzzi,
S., O'Dowd, C. D., Ceburnis, D., and Facchini, M. C.: Primary and Secondary
Organic Marine Aerosol and Oceanic Biological Activity: Recent Results and
New Perspectives for Future Studies, Adv. Meteorol., 2010, 1–10,
10.1155/2010/310682, 2010.Saltzman, E., Savoie, D., Prospero, J., and Zika, R.: Atmospheric
methanesulfonic acid and non-sea-salt sulfate at Fanning and American
Samoa, Geophys. Res. Lett., 12, 437–440,
10.1029/GL012i007p00437, 1985.Shen, W., Ren, L., Zhao, Y., Zhou, L., Dai, L., Ge, X., Kong, S., Yan, Q.,
Xu, H., Jiang, Y., He, J., Chen, M., and Yu, H.: C1-C2 alkyl aminiums in
urban aerosols: Insights from ambient and fuel combustion emission
measurements in the Yangtze River Delta region of China, Environ. Pollut.,
230, 12–21, 10.1016/j.envpol.2017.06.034, 2017.Smith, J. N., Barsanti, K. C., Friedli, H. R., Ehn, M., Kulmala, M.,
Collins, D. R., Scheckman, J. H., Williams, B. J., and McMurry, P. H.:
Observations of aminium salts in atmospheric nanoparticles and possible
climatic implications, P. Natl. Acad. Sci. USA, 107, 6634–6639,
10.1073/pnas.0912127107, 2010.Sorooshian, A., Padró, L. T., Nenes, A., Feingold, G., McComiskey, A.,
Hersey, S. P., Gates, H., Jonsson, H. H., Miller, S. D., Stephens, G. L.,
Flagan, R. C., and Seinfeld, J. H.: On the link between ocean biota
emissions, aerosol, and maritime clouds: Airborne, ground, and satellite
measurements off the coast of California, Global Biogeochem. Cy., 23,
GB4007, 10.1029/2009gb003464, 2009.Tang, X., Price, D., Praske, E., Vu, D. N., Purvis-Roberts, K., Silva, P. J., Cocker III, D. R., and Asa-Awuku, A.: Cloud condensation nuclei (CCN) activity of aliphatic amine secondary aerosol, Atmos. Chem. Phys., 14, 5959–5967, 10.5194/acp-14-5959-2014, 2014.Tao, Y., Ye, X., Jiang, S., Yang, X., Chen, J., Xie, Y., and Wang, R.:
Effects of amines on particle growth observed in new particle formation
events, J. Geophys. Res.-Atmos., 121, 324–335,
10.1002/2015jd024245, 2016.Tao, Y. and Murphy, J. G.: Evidence for the importance of semi-volatile
organic ammonium salts in ambient particulate matter, Environ. Sci.
Technol., 53, 108–116, 10.1021/acs.est.8b03800, 2018.Thompson, A. M.: The oxidizing capacity of the Earth's atmosphere: Probable
past and future changes, Science, 256, 1157–1165,
10.1126/science.256.5060.1157, 1992.Tian, H. Z., Zhu, C. Y., Gao, J. J., Cheng, K., Hao, J. M., Wang, K., Hua, S. B., Wang, Y., and Zhou, J. R.: Quantitative assessment of atmospheric emissions of toxic heavy metals from anthropogenic sources in China: historical trend, spatial distribution, uncertainties, and control policies, Atmos. Chem. Phys., 15, 10127–10147, 10.5194/acp-15-10127-2015, 2015.Uno, I., Osada, K., Yumimoto, K., Wang, Z., Itahashi, S., Pan, X., Hara, Y., Kanaya, Y., Yamamoto, S., and Fairlie, T. D.: Seasonal variation of fine- and coarse-mode nitrates and related aerosols over East Asia: synergetic observations and chemical transport model analysis, Atmos. Chem. Phys., 17, 14181–14197, 10.5194/acp-17-14181-2017, 2017.VandenBoer, T. C., Petroff, A., Markovic, M. Z., and Murphy, J. G.: Size distribution of alkyl amines in continental particulate matter and their online detection in the gas and particle phase, Atmos. Chem. Phys., 11, 4319–4332, 10.5194/acp-11-4319-2011, 2011.VandenBoer, T. C., Markovic, M. Z., Petroff, A., Czar, M. F., Borduas, N.,
and Murphy, J. G.: Ion chromatographic separation and quantitation of alkyl
methylamines and ethylamines in atmospheric gas and particulate matter using
preconcentration and suppressed conductivity detection, J. Chromatogr. A,
1252, 74–83, 10.1016/j.chroma.2012.06.062, 2012.Violaki, K. and Mihalopoulos, N.: Water-soluble organic nitrogen (WSON) in
size-segregated atmospheric particles over the Eastern Mediterranean, Atmos.
Environ., 44, 4339–4345, 10.1016/j.atmosenv.2010.07.056,
2010.Wang, B., Chen, Y., Zhou, S., Li, H., Wang, F., and Yang, T.: The influence
of terrestrial transport on visibility and aerosol properties over the
coastal East China Sea, Sci. Total. Environ., 649, 652–660,
10.1016/j.scitotenv.2018.08.312, 2018.Wang, F., Chen, Y., Meng, X., Fu, J., and Wang, B.: The contribution of
anthropogenic sources to the aerosols over East China Sea, Atmos. Environ.,
127, 22–33, 10.1016/j.atmosenv.2015.12.002, 2016.Wang, L., Khalizov, A. F., Zheng, J., Xu, W., Ma, Y., Lal, V., and Zhang,
R.: Atmospheric nanoparticles formed from heterogeneous reactions of
organics, Nat. Geosci., 3, 238–242, 10.1038/ngeo778, 2010a.Wang, L., Lal, V., Khalizov, A. F., and Zhang, R.: Heterogeneous chemistry
of alkylamines with sulfuric acid: implications for atmospheric formation of
alkylaminium sulfates, Environ. Sci. Technol., 44, 2461–2465,
10.1021/es9036868, 2010b.Xie, H., Feng, L., Hu, Q., Zhu, Y., Gao, H., Gao, Y., and Yao, X.:
Concentration and size distribution of water-extracted dimethylaminium and
trimethylaminium in atmospheric particles during nine campaigns –
Implications for sources, phase states and formation pathways, Sci. Total.
Environ., 631, 130–141, 10.1016/j.scitotenv.2018.02.303,
2018.Yang, G.-P., Zhang, H.-H., Su, L.-P., and Zhou, L.-M.: Biogenic emission of
dimethylsulfide (DMS) from the North Yellow Sea, China and its contribution
to sulfate in aerosol during summer, Atmos. Environ., 43, 2196–2203,
10.1016/j.atmosenv.2009.01.011, 2009.Yang, G.-P., Zhang, S.-H., Zhang, H.-H., Yang, J., and Liu, C.-Y.:
Distribution of biogenic sulfur in the Bohai Sea and northern Yellow Sea and
its contribution to atmospheric sulfate aerosol in the late fall, March
Chem., 169, 23–32, 10.1016/j.marchem.2014.12.008, 2015.Yao, L., Wang, M.-Y., Wang, X.-K., Liu, Y.-J., Chen, H.-F., Zheng, J., Nie, W., Ding, A.-J., Geng, F.-H., Wang, D.-F., Chen, J.-M., Worsnop, D. R., and Wang, L.: Detection of atmospheric gaseous amines and amides by a high-resolution time-of-flight chemical ionization mass spectrometer with protonated ethanol reagent ions, Atmos. Chem. Phys., 16, 14527–14543, 10.5194/acp-16-14527-2016, 2016.Yao, L., Garmash, O., Bianchi, F., Zheng, J., Yan, C., Kontkanen, J.,
Junninen, H., Mazon, S. B., Ehn, M., Paasonen, P., Sipila, M., Wang, M.,
Wang, X., Xiao, S., Chen, H., Lu, Y., Zhang, B., Wang, D., Fu, Q., Geng, F.,
Li, L., Wang, H., Qiao, L., Yang, X., Chen, J., Kerminen, V. M., Petaja, T.,
Worsnop, D. R., Kulmala, M., and Wang, L.: Atmospheric new particle
formation from sulfuric acid and amines in a Chinese megacity, Science, 361,
278–281, 10.1126/science.aao4839, 2018.
You, Y., Kanawade, V. P., de Gouw, J. A., Guenther, A. B., Madronich, S., Sierra-Hernández, M. R., Lawler, M., Smith, J. N., Takahama, S., Ruggeri, G., Koss, A., Olson, K., Baumann, K., Weber, R. J., Nenes, A., Guo, H., Edgerton, E. S., Porcelli, L., Brune, W. H., Goldstein, A. H., and Lee, S.-H.: Atmospheric amines and ammonia measured with a chemical ionization mass spectrometer (CIMS), Atmos. Chem. Phys., 14, 12181–12194, 10.5194/acp-14-12181-2014, 2014.Yu, F. and Luo, G.: Modeling of gaseous methylamines in the global atmosphere: impacts of oxidation and aerosol uptake, Atmos. Chem. Phys., 14, 12455–12464, 10.5194/acp-14-12455-2014, 2014.Yu, H., McGraw, R., and Lee, S.-H.: Effects of amines on formation of sub-3
nm particles and their subsequent growth, Geophys. Res. Lett., 39, L02807,
10.1029/2011gl050099, 2012.Yu, P., Hu, Q., Li, K., Zhu, Y., Liu, X., Gao, H., and Yao, X.:
Characteristics of dimethylaminium and trimethylaminium in atmospheric
particles ranging from supermicron to nanometer sizes over eutrophic
marginal seas of China and oligotrophic open oceans, Sci. Total. Environ.,
572, 813–824, 10.1016/j.scitotenv.2016.07.114, 2016.Yuan, H., Wang, Y., and Zhuang, G.: MSA in Beijing aerosol, Chinese Sci.
Bull., 49, 1020, 10.1360/03wb0186, 2004.Zhang, G., Bi, X., Chan, L. Y., Li, L., Wang, X., Feng, J., Sheng, G., Fu,
J., Li, M., and Zhou, Z.: Enhanced trimethylamine-containing particles
during fog events detected by single particle aerosol mass spectrometry in
urban Guangzhou, China, Atmos. Environ., 55, 121–126,
10.1016/j.atmosenv.2012.03.038, 2012.Zheng, J., Ma, Y., Chen, M., Zhang, Q., Wang, L., Khalizov, A. F., Yao, L.,
Wang, Z., Wang, X., and Chen, L.: Measurement of atmospheric amines and
ammonia using the high resolution time-of-flight chemical ionization mass
spectrometry, Atmos. Environ., 102, 249–259,
10.1016/j.atmosenv.2014.12.002, 2015.Zhou, S., Lin, J., Qin, X., Chen, Y., and Deng, C.: Determination of
atmospheric alkylamines by ion chromatography using 18-crown-6 as mobile
phase additive, J. Chromatogr. A, 1563, 154–161,
10.1016/j.chroma.2018.05.074, 2018.