Abstract. Aerosols in the size class <2.5 μm (6 daytime and 9 nighttime samples) were collected at a pasture site Rondônia, Brazil, during intensive biomass burning period of 16–26 September 2002 as part Large-Scale Biosphere-Atmosphere Experiment Amazonia – Smoke, Aerosols, Clouds, Rainfall Climate (LBA-SMOCC). Homologous series dicarboxylic acids (C2–C11) related compounds (ketocarboxylic α-dicarbonyls) identified using gas chromatography (GC) GC/mass spectrometry (GC/MS). Among species...

Abstract. The detailed molecular composition of laboratory generated limonene ozonolysis secondary organic aerosol (SOA) was studied using ultrahigh-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Approximately 1200 formulas were identified in the SOA over range 140 to 850 Da. Four characteristic groups high relative abundance species observed; they indicate an array accretion products that retain a large fraction skeleton. each are related one another by...

Abstract. Measurements of organosulfates in ambient aerosols provide insight to the extent secondary organic aerosol (SOA) formation from mixtures biogenic gases and anthropogenic pollutants. Organosulfates have, however, proved analytically challenging quantify, due lack authentic standards complex sample matrix which are observed. This study presents a sensitive accurate new analytical method for quantification based upon ultra-performance liquid chromatography (UPLC) with negative...

The composition and sources of fine particulate matter (PM2.5) were investigated in rural urban locations Iowa, located the agricultural industrial Midwestern United States, from April 2009 to December 2012. Major chemical contributors PM2.5 mass sulfate, nitrate, ammonium, organic carbon. Non-parametric statistical analyses demonstrated that two sites had significantly enhanced levels crustal materials (Si, Al) driven by activities unpaved roads. Meanwhile, three areas secondary aerosols...

Atmospheric aerosol samples ( n = 84) were collected at Gosan site, Jeju Island, South Korea between April 2003 and 2004 for the measurements of total nitrogen (TN) its isotopic ratio δ 15 N) as well species (NH 4 + NO 3 − ). Measurements also conducted remained (remained removed (removed on HCl fume treatment. A pronounced seasonal variation was found in N TN, (mostly NH ), The highest mean values TN (+16.9‰ ± 4.5‰) (+20.2‰ 5.2‰) are detected summer (June–August) whereas lowest (+12.9‰ 3.4‰...

Abstract. Organosulfates are important components of atmospheric organic aerosols, yet their structures, abundances, sources and formation processes not adequately understood. This study presents the identification quantitation benzyl sulfate in which is first confirmed organosulfate with aromatic carbon backbone. Benzyl was identified quantified fine particulate matter (PM2.5) collected Lahore, Pakistan, during 2007–2008. An authentic standard synthesized, standardized, aerosols quadrupole...

Aerosol samples ( n = 84) were collected continuously from April 2003 to 2004 at Gosan site in Jeju Island, South Korea. The analyzed for diacids, ketoacids, and α ‐dicarbonyls, as well organic carbon (OC), elemental (EC), water‐soluble (WSOC), inorganic ions. Oxalic acid (C 2 ) was the most abundant followed by malonic 3 all seasons. mean concentration (784 ng m −3 of total diacids –C 12 their relative abundances species detected, OC WSOC found be highest summer, whereas those ketoacids...

Abstract. Reactions of the hydroxyl (OH) and peroxy (HO2 RO2) radicals play a central role in chemistry atmosphere. In addition to controlling lifetimes many trace gases important issues global climate change, OH radical reactions initiate oxidation volatile organic compounds (VOCs) which can lead production ozone secondary aerosols Previous measurements these forest environments characterized by high mixing ratios isoprene low nitrogen oxides (NOx) (typically less than 1–2 ppb) have shown...

Peroxy radicals play important roles in the atmospheric oxidation of organic compounds and formation ozone secondary aerosol. There are few peroxy radical measurement techniques; most common, chemical amplification using CO NO, requires use toxic reagents, its calibration factor is very sensitive to relative humidity. We present a new method for quantifying radicals, ECHAMP (Ethane CHemical AMPlifier). Sampled air mixed with NO C2H6 (rather than CO), effecting series reactions that...

Abstract. Change in secondary organic aerosols (SOAs) has been predicted to be highly uncertain the future atmosphere Asia. To better quantify SOA change, we examine sub-decadal (2001–2008) trend major surrogate compounds (C2–C10 diacids) of atmospheric from Gosan site on Cheju Island, South Korea. The is influenced by pollution outflows eastern molecular distributions diacids were characterized predominance oxalic (C2) acid followed malonic (C3) and succinic (C4) acids each year. seasonal...

Abstract. Ground-level ozone (O3) is an important pollutant that affects both global climate change and regional air quality, with the latter linked to detrimental effects on human health ecosystems. Ozone not directly emitted in atmosphere but formed from chemical reactions involving volatile organic compounds (VOCs), nitrogen oxides (NOx= NO + NO2) sunlight. The photochemical nature of makes implementation reduction strategies challenging a good understanding its formation chemistry...

Abstract. Aerosols in the size class <2.5 μm (6 daytime and 9 nighttime samples) were collected at a pasture site Rondônia, Brazil, during intensive biomass burning period of 16–26 September 2002 as part Large-Scale Biosphere-Atmosphere Experiment Amazonia – Smoke, Aerosols, Clouds, Rainfall Climate (LBA-SMOCC). Homologous series dicarboxylic acids (C2–C11) related compounds (ketocarboxylic dicarbonyls) identified using gas chromatography GC/mass spectrometry (GC/MS). Among species...

Abstract. Peroxy radicals were measured in a mixed deciduous forest atmosphere Bloomington, Indiana, USA, during the Indiana Radical, Reactivity and Ozone Production Intercomparison (IRRONIC) summer of 2015. Total peroxy ([XO2]≡[HO2]+Σ[RO2]) by newly developed technique involving chemical amplification using nitric oxide (NO) ethane (C2H6) followed NO2 detection cavity-attenuated phase-shift spectroscopy (hereinafter referred to as ECHAMP – Ethane CHemical AMPlifier). The sum hydroperoxy...

Ambient particulate matter (PM2.5 and PM10) concentrations were measured during two different seasons (summer winter) at three locations of Gurugram which is located in the Indo-Gangetic plain India. The ambient both PM2.5 PM10 higher winter season (PM2.5: 261 μg·m-3; PM10: 440 μg·m-3) when compared to summer period 114 202 μg·m-3). Potential Source Contribution Function (PSCF) analysis suggests significant seasonal variation potential contributing over study area. PSCF that cross country...

Abstract. Ground level ozone (O3) is an important pollutant that affects both global climate change and regional air quality, with the latter linked to detrimental effects on human health ecosystems. Ozone not directly emitted in atmosphere but formed from chemical reactions involving volatile organic compounds (VOCs), nitrogen oxides (NOx = NO+NO2) sunlight. The photochemical nature of makes implementation reduction strategies challenging a good understanding its formation chemistry...

Abstract. Measurements of organosulfates in ambient aerosols provide insight to the extent secondary organic aerosol (SOA) formation from mixtures biogenic gases and anthropogenic pollutants. Organosulfates have, however, proved analytically challenging measure. This study presents a sensitive new analytical method for quantification based upon ultra-performance liquid chromatography with negative electrospray ionization mass spectrometry (UPLC-ESI-MS/MS). The separation is hydrophilic...

Abstract. Organosulfates are important components of atmospheric organic aerosols, yet their structures, abundances, sources and formation processes not adequately understood. This study presents the identification quantitation benzyl sulfate in which is first reported organosulfate with aromatic carbon backbone. Benzyl was identified quantified fine particulate matter (PM2.5) collected Lahore, Pakistan during 2007–2008. An authentic standard synthesized, standardized, aerosols using...

Abstract Complex fluids are of nobleness due to their unique mechanical responses applied stress, which different from simple fluids. Therefore, the current study encapsulated behavior SH‐wave in a complex fluid layer overlying fiber‐reinforced half‐space with six cases considered at common interface. These involve various interface conditions, including perfect bonding, spring layer, an infinitely thin membrane loose combined spring‐membrane and bonding. Precisely, effect strength,...

Abstract. Peroxy radicals were measured in a mixed deciduous forest atmosphere Bloomington, Indiana, USA, during the Indiana Radical, Reactivity and Ozone Production Intercomparison (IRRONIC) summer of 2015. Total peroxy ([XO2] ≡ [HO2] + Ʃ[RO2]) by newly developed technique involving nitric oxide (NO) – ethane (C2H6) chemical amplification followed NO2 detection cavity attenuated phase shift spectroscopy (hereinafter referred to as ECHAMP). The sum hydroperoxy (HO2) portion organic ([HO2*] =...