Concurrent increases of PM2.5 and Ozone observed in Seoul, May 2019

&#160;In Seoul, PM2.5 concentrations were frequently elevated with O3 in May 2019. The most abundant constituent of PM2.5 was nitrate, which was the best correlated with OC (organic carbon) as well as NH4+. An intensive experiment was conducted in the eastern part of Seoul from March 29 to June 19, 2019. Measurement was made for PM2.5 and its chemical composition including NO3-, SO42-, NH4+ , OC, EC (elemental carbon), and reactive gases including O3, NO, NO2, CO, HONO, HNO3, NH3, and SO2, and meteorological variables including vertical winds and mixed layer height (MLH). The particle number concentration was measured using SMPS (Scanning Mobility Particle Sizer). All measurements were averaged for 1 hour according to the resolution of PM2.5 chemical composition. For the entire experiment, the mean mass concentrations of PM2.5, NO3-, SO42-, NH4+, OC, and EC were 20.40 &#956;g/m3, 4.07 &#956;g/m3, 2.62 &#956;g/m3, 2.01 &#956;g/m3, 4.01 &#956;g/m3, and 1.04 &#956;g/m3, respectively. For reactive gases, the mean concentration was 1.03 ppbv for HONO, 0.70 ppbv for HNO3, 14.87 ppbv for NH3, 2.77 ppbv for SO2, and 48.79 ppbv for O3.&#160;&#160;The maximum PM2.5 concentration of 72.81 &#956;g/m3 was observed under the influence of weak Asian dust event in the end of April. In May, there were three distinct episodes with highly enhanced PM2.5. In the early May, the maximum nitrate concentration (36.11 &#956;g/m3) was observed with high HONO (2.41 ppbv) on 4 May. In the middle of May, PM2.5 was raised with SO42- under stagnant condition. On 25 May, PM2.5 was raised up to 92 &#956;g/m3 with high nitrate concentration (18.56 &#956;g/m3) , when O3 reached 205 ppbv. In this episode, O3 concentration remained around 90 ppbv at night and OC and EC were well correlated with highly enhanced K+. Thus, the concurrent enhancement of PM2.5 and O3 was likely due to the influence of aged biomass combustion plume laden air transported from southeast China. At the same time, HNO3 and HONO concentration was highly elevated, indicating that heterogeneous reactions played a role.

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Chemical composition, sources, and processes of urban aerosols during summertime in northwest China: insights from high-resolution aerosol mass spectrometry

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-12593-2014 ◽

2014 ◽

Vol 14 (23) ◽

pp. 12593-12611 ◽

Cited By ~ 87

Author(s):

J. Xu ◽

Q. Zhang ◽

M. Chen ◽

X. Ge ◽

J. Ren ◽

...

Keyword(s):

Chemical Composition ◽

High Resolution ◽

Coal Combustion ◽

Northwest China ◽

Temporal Variations ◽

Organic Mass ◽

Scanning Mobility Particle Sizer ◽

Aerosol Mass ◽

Early Afternoon ◽

Particle Sizer

Abstract. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed along with a scanning mobility particle sizer (SMPS) and a multi-angle absorption photometer (MAAP) to measure the temporal variations of the mass loading, chemical composition, and size distribution of submicron particulate matter (PM1) in Lanzhou, northwest China, during 11 July–7 August 2012. The average (PM1 mass concentration including non-refractory (PM1 (NR-(PM1) measured by HR-ToF-AMS and black carbon (BC) measured by MAAP during this study was 24.5 μg m−3 (ranging from 0.86 to 105 μg m−3), with a mean composition consisting of 47% organics, 16% sulfate, 12% BC, 11% ammonium, 10% nitrate, and 4% chloride. Organic aerosol (OA) on average consisted of 70% carbon, 21% oxygen, 8% hydrogen, and 1% nitrogen, with the average oxygen-to-carbon ratio (O / C) of 0.33 and organic mass-to-carbon ratio (OM / OC) of 1.58. Positive matrix factorization (PMF) of the high-resolution organic mass spectra identified four distinct factors which represent, respectively, two primary OA (POA) emission sources (traffic and food cooking) and two secondary OA (SOA) types – a fresher, semi-volatile oxygenated OA (SV-OOA) and a more aged, low-volatility oxygenated OA (LV-OOA). Traffic-related hydrocarbon-like OA (HOA) and BC displayed distinct diurnal patterns, both with peak at ~ 07:00–11:00 (BJT: UTC +8), corresponding to the morning rush hours, while cooking-emission related OA (COA) peaked during three meal periods. The diurnal profiles of sulfate and LV-OOA displayed a broad peak between ~ 07:00 and 15:00, while those of nitrate, ammonium, and SV-OOA showed a narrower peak between ~ 08:00–13:00. The later morning and early afternoon maximum in the diurnal profiles of secondary aerosol species was likely caused by downward mixing of pollutants aloft, which were likely produced in the residual layer decoupled from the boundary layer during nighttime. The mass spectrum of SV-OOA was similar to that of coal combustion aerosol and likely influenced by coal combustion activities in Lanzhou during summer. The sources of BC were estimated by a linear decomposition algorithm that uses the time series of the NR-PM1 components. Our results indicate that a main source of BC was local traffic (47%) and that transport of regionally processed air masses also contributed significantly to BC observed in Lanzhou. Finally, the concentration and source of polycyclic aromatic hydrocarbons (PAHs) were evaluated.

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Chemical composition, sources, and processes of urban aerosols during summertime in Northwest China: insights from High Resolution Aerosol Mass Spectrometry

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-16187-2014 ◽

2014 ◽

Vol 14 (11) ◽

pp. 16187-16242 ◽

Cited By ~ 3

Author(s):

J. Xu ◽

Q. Zhang ◽

M. Chen ◽

X. Ge ◽

J. Ren ◽

...

Keyword(s):

Chemical Composition ◽

High Resolution ◽

Coal Combustion ◽

Northwest China ◽

Temporal Variations ◽

Scanning Mobility Particle Sizer ◽

Night Time ◽

Aerosol Mass ◽

Early Afternoon ◽

Particle Sizer

Abstract. An aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed along with a Scanning Mobility Particle Sizer (SMPS) and a Multi Angle Absorption Photometers (MAAP) to measure the temporal variations of the mass loading, chemical composition, and size distribution of sub-micrometer particulate matter (PM1) in Lanzhou, northwest China, during 12 July–7 August 2012. The average PM1 mass concentration including non-refractory PM1 (NR-PM1) measured by HR-ToF-AMS and black carbon (BC) measured by MAAP during this study was 24.5 μg m−3 (ranging from 0.86 to 105μg m−3), with a mean composition consisting of 47% organics, 16% sulfate, 12% BC, 11% ammonium, 10% nitrate, and 4% chloride. The organics was consisted of 70% carbon, 21% oxygen, 8% hydrogen, and 1% nitrogen, with the average oxygen-to-carbon ratio (O / C) of 0.33 and organic mass-to-carbon ratio (OM / OC) of 1.58. Positive matrix factorization (PMF) of the high-resolution mass spectra of organic aerosols (OA) identified four distinct factors which represent, respectively, two primary OA (POA) emission sources (traffic and food cooking) and two secondary OA (SOA) types – a fresher, semi-volatile oxygenated OA (SV-OOA) and a more aged, low-volatility oxygenated OA (LV-OOA). Traffic-related hydrocarbon-like OA (HOA) and BC displayed distinct diurnal patterns both with peak at ~07:00–11:00 (BJT: UTC +8) corresponding to the morning rush hours, while cooking OA (COA) peaked during three meal periods. The diurnal profiles of sulfate and LV-OOA displayed a broad peak between ∼07:00–15:00, while those of nitrate, ammonium, and SV-OOA showed a narrower peak at ~08:00–13:00. The later morning and early afternoon peak in the diurnal profiles of secondary aerosol species was likely caused by mixing down of pollutants aloft, which were likely produced in the residual layer decoupled from the boundary layer during night time. The mass spectrum of SV-OOA also showed similarity with that of coal combustion aerosol, likely contributed by coal combustion activities in Lanzhou during summer. The sources of BC were estimated by a linear decomposition algorithm that uses the time series of the NR-PM1 components. Our results indicate that a main source of BC was local traffic (47%) and that transport of regionally processes air masses also contributed significantly to BC observed in Lanzhou. Finally, the concentration and source of polycyclic aromatic hydrocarbons (PAHs) were evaluated.

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Modeling Nitrate Transport in a Small Upland Stream

Water Quality Research Journal ◽

10.2166/wqrj.1978.013 ◽

1978 ◽

Vol 13 (1) ◽

pp. 161-174

Author(s):

W.N. Stammers ◽

J.B. Robinson ◽

H.R. Whiteley ◽

N. K. Kaushik ◽

P. Sain

Keyword(s):

Peak Flow ◽

Nitrate Concentration ◽

Stream Water ◽

Surface Flow ◽

Nitrate Transport ◽

Stream Channel ◽

Southern Ontario ◽

Flow Rates ◽

High Nitrate Concentration ◽

The Mean

Abstract Swifts Brook, a small headwater stream within the Grand River Watershed in Southern Ontario, originates, during baseflow periods, in a spring with a high nitrate concentration. The spring, which is the principle source of summer streamflow for the brook, has peak flow rates of up to 5.5 l sec 1 in March and April and minimum flowrates as low as 2.8 l sec in August or September. The nitrate concentration in the spring is highest during periods of highest flowrate and lowest in October or November. The mean annual concentrations of NO3 ~*-N in the spring outflow, weighted by flowrate, were 4.3 mg SL * in 1975 and 4.1 mg l in 1976. During dry summer conditions a two km reach of the main channel, beginning at the spring, receives no surface flow contributions from ephemeral tributaries. Stream processes in this portion of the stream channel were studied in detail (Robinson et al. 1977). The location of the spring and study reaches are shown in Fig. 1. For this reach, the stream water surface width varied from 0.7 to 3.8 meters and the water depth and average velocity vary from 0.08 to 0.23 meters and 0.004 to 0.05 m sec respectively.

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Influence of Upslope Fog on Hygroscopicity and Chemical Composition of Aerosols at a Forest Site in Taiwan

10.5194/egusphere-egu2020-6387 ◽

2020 ◽

Author(s):

Chia-Li Chen ◽

Ting-Yu Chen ◽

Hui-Ming Hung ◽

Ping-Wen Tsai ◽

Wei-Nai Chen ◽

...

Keyword(s):

Chemical Composition ◽

Carboxylic Acid ◽

Acid Group ◽

Forest Site ◽

Particle Removal ◽

Carboxylic Acid Group ◽

Scanning Mobility Particle Sizer ◽

Aerosol Mass ◽

Rural Aerosols ◽

Particle Sizer

This study investigated the influence of upslope fog formation on the chemical composition and single hygroscopicity parameter (&#954;) of rural aerosols. The compositions were monitored using a mini compact time-of-flight aerosol mass spectrometer (mini-C-ToF-AMS), and a scanning mobility particle sizer (SMPS) from Dec. 1st to Dec. 24th, 2018 at the Xitou forest site (23.40&#176;N, 120.47&#176;E, 1,178 m asl) in Taiwan. Ambient wet aerosol particles were collected by a 13-stage nano-MOUDI II impactor (micro-orifice uniform deposit impactors) and analyzed using a Fourier-transform infrared spectrometer with an attenuated total reflectance accessory (FTIR-ATR). The single hygroscopicity parameter (&#954;) of aerosols derived from the comparison of AMS pToF size distribution using the &#954;-K&#246;hler equation and FTIR-ATR measurement. The moderate correlation (r = 0.73) between the oxidized oxygenated organic aerosol (OOA) and CO evidenced the upstream anthropogenic emission transport by sea/land breezes. The decreasing (aerosol mass)/CO ratio with decreasing visibility trends during in-fog periods at two dense foggy events indicated that the fog activation scavenging mechanism dominated the aerosol particle removal. The inconsistency of online real-time AMS and offline FTIR-ATR measurement for submicrometer particles indicated that the evaporation loss of HNO3 or NH4NO3 particles during MOUDI filter sampling could lead to the unavailable &#954; retrieval for nitrate-containing particles at non-foggy daytime and the discrepancy of aerosol acidity. Similar &#954; ranges of organic carboxylic acid group particles (0.1 < &#954;p-org < 0.3), ammonium-containing, and sulfate-containing particles (0.2 < &#954;p-NH4 or &#954;p-SO4< 0.5) but ambiguous nitrate-containing particles (0.4 < &#954;p-NO3 < 0.6 or 0.6 < &#954;p-NO3 < 0.8) were observed at foggy daytime, suggesting that ammonium sulfate and organic carboxylic acid compounds were more likely internal mixture particles with similar hygroscopicity and physicochemical mixing state influenced by upslope fog. However, the distinct &#954; ranges of sulfate-containing particles (0.5 < &#954;p-SO4 < 0.7 or 0.6 < &#954;p-SO4 < 0.8) and organic carboxylic acid group particles (0.1 < &#954;p-org < 0.2) revealed the different chemical and physical properties of external mixture particles at non-foggy daytime.&#160;&#160;

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Insights into the growth of newly formed particles in a subtropical urban environment

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-13475-2015 ◽

2015 ◽

Vol 15 (23) ◽

pp. 13475-13485 ◽

Cited By ~ 2

Author(s):

F. Salimi ◽

L. R. Crilley ◽

S. Stevanovic ◽

Z. Ristovski ◽

M. Mazaheri ◽

...

Keyword(s):

Chemical Composition ◽

Quality Parameters ◽

Scanning Mobility Particle Sizer ◽

Particle Volume ◽

Aerosol Mass ◽

Organic Markers ◽

Particle Sizer ◽

Subtropical Environment ◽

Aerosol Chemical Composition

Abstract. The role of different chemical compounds, particularly organics, involved in the new particle formation (NPF) and its consequent growth are not fully understood. Therefore, this study was conducted to investigate the chemical composition of aerosol particles during NPF events in an urban subtropical environment. Aerosol chemical composition was measured along with particle number size distribution (PNSD) and several other air quality parameters at five sites across an urban subtropical environment. An Aerodyne compact Time-of-Flight Aerosol Mass Spectrometer (c-ToF-AMS) and a TSI Scanning Mobility Particle Sizer (SMPS) measured aerosol chemical composition (particles above 50 nm in vacuum aerodynamic diameter) and PNSD (particles within 9–414 nm in mobility diameter), respectively. Five NPF events, with growth rates in the range 3.3–4.6 nm, were detected at two of the sites. The NPF events happened on relatively warmer days with lower condensation sink (CS). Temporal percent fractions of organics increased after the particles grew enough to have a significant contribution to particle volume, while the mass fraction of ammonium and sulfate decreased. This uncovered the important role of organics in the growth of newly formed particles. Three organic markers, factors f43, f44 and f57, were calculated and the f44 vs. f43 trends were compared between nucleation and non-nucleation days. K-means cluster analysis was performed on f44 vs. f43 data and it was found that they follow different patterns on nucleation days compared to non-nucleation days, whereby f43 decreased for vehicle-emission-generated particles, while both f44 and f43 decreased for NPF-generated particles. It was found for the first time that vehicle-generated and newly formed particles cluster in different locations on f44 vs. f43 plot, and this finding can be potentially used as a tool for source apportionment of measured particles.

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Analyse der Partikelbildung aus der Elektrospray‐Flammensprühpyrolyse mittels Scanning Mobility Particle Sizer

Chemie Ingenieur Technik ◽

10.1002/cite.202000195 ◽

2021 ◽

Author(s):

Malte Bierwirth ◽

Vinzent Olszok ◽

Varun Aiyar Ganesan ◽

Jalal Poostforooshan ◽

Alfred P. Weber

Keyword(s):

Scanning Mobility Particle Sizer ◽

Particle Sizer

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Denitrification kinetics of high nitrate concentration water: pH effect on inhibition and nitrite accumulation

Water Research ◽

10.1016/s0043-1354(97)00260-1 ◽

1998 ◽

Vol 32 (3) ◽

pp. 831-839 ◽

Cited By ~ 300

Author(s):

Charles Glass ◽

JoAnn Silverstein

Keyword(s):

Nitrate Concentration ◽

Ph Effect ◽

Nitrite Accumulation ◽

High Nitrate Concentration ◽

Water Ph ◽

Denitrification Kinetics ◽

Kinetics Of

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Zehn Jahre Messungen der Anzahl- und lungendeponierbaren Oberflächenkonzentration ultrafeiner Partikel im städtischen Hintergrund im Ruhrgebiet/Ten years of measurements of the number and lung deposited surface concentration of ultrafine particles in the urban background in the Ruhr Area

Gefahrstoffe ◽

10.37544/0949-8036-2020-01-02-27 ◽

2020 ◽

Vol 80 (01-02) ◽

pp. 25-32

Author(s):

C. Asbach ◽

T. A. J. Kuhlbusch ◽

U. Quass ◽

H. Kaminski

Keyword(s):

Surface Area ◽

Ultrafine Particles ◽

Surface Concentration ◽

Scanning Mobility Particle Sizer ◽

Urban Background ◽

Ruhr Area ◽

Nanoparticle Surface ◽

Particle Sizer

Seit Anfang 2009 werden an einer städtischen Hintergrundmessstation in Mülheim-Styrum im westlichen Ruhrgebiet Anzahlkonzentration, Anzahlgrößenverteilung und lungendeponierbare Oberflächenkonzentration submikroner und ultrafeiner Partikel gemessen. Die dazu eingesetzten Messgeräte Scanning Mobility Particle Sizer (SMPS) und Nanoparticle Surface Area Monitor (NSAM) erwiesen sich als gut geeignet für derartige Messaufgaben. Insbesondere das NSAM ist sehr robust und zuverlässig und wird daher neben der Bestimmung der lungendeponierbaren Oberflächenkonzentration auch zur Funktionsüberwachung des SMPS verwendet. Die ultrafeinen Partikel an der Messstation stammen zu einem großen Teil von einer nahegelegenen Autobahn sowie diversen anderen Quellen in der näheren Umgebung. Der etwa 20 km südlich gelegene Flughafen Düsseldorf scheint keinen merklichen Einfluss zu haben. Eine Auswertung der Wochengänge zeigte überraschenderweise, dass in allen Jahren samstagnachts die im Wochenverlauf höchste Anzahlkonzentration von Partikeln >100 nm gemessen wurde. Während an allen anderen Wochentagen die mittleren Konzentrationen seit 2009 kontinuierlich gesunken sind, blieb die Höhe des Maximums in der Nacht von Samstag auf Sonntag nahezu konstant, was auf eine unveränderte, zeitlich sehr begrenzte Quelle hindeutet.

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Influence of the sex and type of tissue on the basic chemical composition and the content of minerals in the sirloin and offal of fattener pigs

Canadian Journal of Animal Science ◽

10.1139/cjas-2018-0085 ◽

2019 ◽

Vol 99 (2) ◽

pp. 343-348 ◽

Cited By ~ 2

Author(s):

Marek Babicz ◽

Anna Kasprzyk ◽

Kinga Kropiwiec-Domańska

Keyword(s):

Chemical Composition ◽

Mineral Content ◽

Cadmium Concentration ◽

Pork Meat ◽

Threshold Values ◽

Large White ◽

Sodium Calcium ◽

Mineral Components ◽

Longissimus Lumborum ◽

The Mean

The aim of the study was to determine the basic chemical composition and mineral content in the sirloin and offal of fattener pigs, taking their sex into consideration. In addition, comparative analysis of the content of chemical and mineral components in the sirloin and offal was performed. The experimental material included 24 crossbred (Polish Landrace × Polish Large White) fatteners, from which samples of sirloin (musculus longissimus lumborum), liver, heart, and kidneys were collected for the analysis. A significant effect of the sex on the fat content in the sirloin and liver and on the level of magnesium (Mg), zinc, and iron (Fe) in the sirloin was demonstrated. Significant differences were found in the basic chemical composition and mineral content between the sirloin and the offal. In comparison with the liver, the sirloin contained lower amounts of protein and fat and higher potassium and Mg contents. In turn, the offal was shown to be a rich source of sodium, calcium, and trace elements (Fe, manganese, and copper). The mean cadmium concentration in the sirloin and offal was significantly lower than the threshold values for these elements, i.e., it accounted for 26% and 6.2% (liver)–19.5% (heart) of the allowable content of this element in pork meat and offal.

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