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Jeffrey L Collett - One of the best experts on this subject based on the ideXlab platform.
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airborne characterization of smoke marker ratios from prescribed burning
Atmospheric Chemistry and Physics, 2014Co-Authors: Amy P Sullivan, Andrew A May, Taehyoung Lee, G R Mcmeeking, S M Kreidenweis, S K Akagi, Robert J Yokelson, Shawn Urbanski, Jeffrey L CollettAbstract:Abstract. A Particle-Into-Liquid Sampler – Total Organic Carbon (PILS-TOC) and fraction collector system was flown aboard a Twin Otter aircraft sampling prescribed burning emissions in South Carolina in November 2011 to obtain smoke marker measurements. The fraction collector provided 2 min time-integrated offline samples for carbohydrate (i.e., smoke markers Levoglucosan, mannosan, and galactosan) analysis by high-performance anion-exchange chromatography with pulsed amperometric detection. Each fire location appeared to have a unique ΔLevoglucosan/Δwater-soluble organic carbon (WSOC) ratio (RF01/RF02/RF03/RF05 = 0.163 ± 0.007 μg C μg−1 C, RF08 = 0.115 ± 0.011 μg C μg−1 C, RF09A = 0.072 ± 0.028 μg C μg−1 C, and RF09B = 0.042 ± 0.008 μg C μg−1 C, where RF means research flight). These ratios were comparable to those obtained from controlled laboratory burns and suggested that the emissions sampled during RF01/F02/RF03/RF05 were dominated by the burning of grasses, RF08 by leaves, RF09A by needles, and RF09B by marsh grasses. These findings were further supported by the Δgalactosan/ΔLevoglucosan ratios (RF01/RF02/RF03/RF05 = 0.067 ± 0.004 μg μg−1, RF08 = 0.085 ± 0.009 μg μg−1, and RF09A = 0.101 ± 0.029 μg μg−1) obtained as well as by the ground-based fuel and filter sample analyses during RF01/RF02/RF03/RF05. Differences between Δpotassium/ΔLevoglucosan ratios obtained for these prescribed fires vs. laboratory-scale measurements suggest that some laboratory burns may not accurately represent potassium emissions from prescribed burns. The ΔLevoglucosan/ΔWSOC ratio had no clear dependence on smoke age or fire dynamics suggesting that this ratio is more dependent on the type of fuel being burned. Levoglucosan was stable over a timescale of at least 1.5 h and could be useful to help estimate the air quality impacts of biomass burning.
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Levoglucosan stability in biomass burning particles exposed to hydroxyl radicals
Geophysical Research Letters, 2010Co-Authors: Christopher J. Hennigan, Amy P Sullivan, Jeffrey L Collett, Allen L RobinsonAbstract:[1] Experiments were carried out in a smog chamber to investigate the oxidation of Levoglucosan in biomass burning particles exposed to gas-phase hydroxyl radicals (OH). The experiments featured atmospherically-relevant particle and oxidant concentrations and both high and low relative humidity conditions. In every experiment, we observed Levoglucosan decay in particles exposed to OH. The extent of decay ranged from ∼20% to ∼90% and was strongly correlated to the integrated OH exposure. Increased relative humidity did not enhance or impede reaction. Relative kinetics indicate that Levoglucosan has an atmospheric lifetime of 0.7–2.2 days when biomass burning particles are exposed to 1 × 106 molecules cm−3 of OH (typical average summertime conditions). This implies that Levoglucosan reacts with OH on a timescale similar to that of transport and deposition, which has important implications for the use of Levoglucosan as a tracer for biomass burning emissions in source apportionment studies.
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a method for smoke marker measurements and its potential application for determining the contribution of biomass burning from wildfires and prescribed fires to ambient pm2 5 organic carbon
Journal of Geophysical Research, 2008Co-Authors: Amy P Sullivan, Sonia M Kreidenweis, William C Malm, G R Mcmeeking, Amanda S Holden, L A Patterson, Cyle Wold, Jeffrey L CollettAbstract:[1] Biomass burning is an important source of particulate organic carbon (OC) in the atmosphere. Quantifying this contribution in time and space requires a means of routinely apportioning contributions of smoke from biomass burning to OC. Smoke marker (for example, Levoglucosan) measurements provide the most common approach for making this determination. A lack of source profiles for wildfires and prescribed fires and the expense and complexity of traditional smoke marker measurement methods have thus far limited routine estimates of these contributions to ambient aerosol concentrations and regional haze. We report here on the collection of source profiles for combustion of numerous wildland fuels and on the development of an inexpensive and robust technique for routine smoke marker measurements. Hi-Volume filter source samples were collected during two studies at the Fire Science Laboratory in Missoula, MT in 2006 and 2007. Levoglucosan (and other carbohydrates) were measured in these samples using high-performance anion-exchange chromatography with pulsed amperometric detection. Results of this analysis along with water-soluble potassium, OC, and elemental carbon are presented. The results show that emissions of Levoglucosan are fairly correlated with OC with an average ratio of 0.031 μg C/μg C. Further, there was a definite pattern that emerged based on fuel component burned with the typical Levoglucosan/OC ratio of branches > straw > needles > leaves. Additionally, this carbohydrate measurement method appears to provide fingerprint information about the type of fuel burned that could help constrain profiles chosen for aerosol source apportionment and lead to a better determination of source contributions from biomass burning.
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determination of Levoglucosan in biomass combustion aerosol by high performance anion exchange chromatography with pulsed amperometric detection
Atmospheric Environment, 2006Co-Authors: Guenter Engling, Jeffrey L Collett, Christian M Carrico, Sonia M Kreidenweis, William C Malm, Emily Lincoln, Yoshiteru Iinuma, Hartmut HerrmannAbstract:Abstract Atmospheric particulate matter can be strongly affected by smoke from biomass combustion, including wildfires, prescribed burns, and residential wood burning. Molecular source tracer techniques help determine contributions of biomass smoke to particle concentrations if representative source profiles are available. Various wood smoke source profiles have been generated for residential wood burning; however, few emission data are available for the combustion of biomass under open-burning conditions. Anhydrosugars, produced as thermal degradation products of cellulose and hemicellulose, are typically analyzed by gas chromatography-mass spectrometry (GC-MS) after chemical derivatization. A simpler alternative analytical method, based on high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), was developed here and utilized to measure several isomeric anhydrosugars (Levoglucosan, mannosan, and galactosan) in primary smoke aerosol from various types of biomass and from different combustion conditions representative of prescribed and wildfires. Highly varying patterns were observed in the emission profiles of various molecular markers as a function of fuel type and combustion conditions. Emission factors of Levoglucosan were a strong function of fuel type, combustion phase, and uphill versus downhill burn direction, varying from 36 to 1368 μg mg−1 organic carbon. Fuel type was the most important determinant, causing variations in emission factors of Levoglucosan over an order of magnitude, while combustion phase and burn direction generally affected emission factors by a factor of 2–3. Mannosan and galactosan showed emission trends similar to Levoglucosan. Levoglucosan emission factors from selected samples were compared to data obtained by two independent analytical methods, high-performance liquid chromatography (HPLC-MS) and GC-MS, showing rather good agreement. The HPAEC-PAD analytical method offers a simple alternative to GC-MS for future studies of aerosol concentrations of anhydrosugars, enabling more accurate estimates of contributions from biomass combustion to ambient particle concentrations.
H Puxbaum - One of the best experts on this subject based on the ideXlab platform.
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chemical characterisation of fine particle emissions from wood stove combustion of common woods growing in mid european alpine regions
Atmospheric Environment, 2008Co-Authors: Christoph Schmidl, Alexandre Caseiro, Anne Kaspergiebl, Petra Kotianova, Axel Erne, Heidi Aue, H PuxbaumAbstract:Woodsmoke samples derived from the combustion of beech, oak, spruce, larch and softwood briquettes in a closed stove have been collected and analysed so as to derive chemical profiles for ambient particulate matter (PM) source apportionment studies, for example, by CMB modelling. Trace metals, soluble ions, carbon species total carbon (TC), elemental carbon (EC) and organic carbon (OC), anhydrosugars, polar and non-polar trace organics, cellulose and humiclike substances (HULIS) have been measured. The inorganic and most organic components were not significantly different for the different woods, so that one profile could be derived for CMB modelling. The anhydrosugar Levoglucosan was present in high concentrations, 4–15% w/w, and for the mix of woods important for Austria, one conversion factor can be used to derive the mass of woodsmoke from the Levoglucosan concentration in ambient air. Mannosan is also a major component, 0.3–4% w/w, which, taken together with the Levoglucosan content, permits estimates to be made of the proportion of hard- and softwood smoke to ambient PM. r 2007 Elsevier Ltd. All rights reserved.
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determination of saccharides in atmospheric aerosol using anion exchange high performance liquid chromatography and pulsed amperometric detection
Journal of Chromatography A, 2007Co-Authors: Alexandre Caseiro, M Claeys, Iain L Marr, Anne Kaspergiebl, H PuxbaumAbstract:Abstract An improved method is described for the quantification of primary sugars, sugar alcohols and anhydrosugars in atmospheric aerosols, making use of separation by high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). Quartz fibre filters from high-volume samplers were extracted with water and the extract injected directly. Repeatability is typically 4% RSD, for e.g. Levoglucosan at 50 ng m−3 in air, better for winter levels around 700 ng m−3. Limits of detection for individual sugars are in the range 0.02–0.05 μg mL−1 in solution, corresponding to 2–5 ng m−3 from a 20 m3 air sample. The overlap of arabitol and levogluocosan is overcome by using a Dionex PA-1 column, with appropriate control of eluent composition, and peak deconvolution software, allowing quantification of both sugars in difficult summer samples containing low-levels of Levoglucosan. Analysis of a set of ambient aerosol samples by both GC-flame ionization detection and HPAEC-PAD shows good agreement. The new method has the advantage of requiring no sample pretreatment or derivatization and is thus well suited to handling large numbers of samples.
Guenter Engling - One of the best experts on this subject based on the ideXlab platform.
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Stable carbon isotope ratio analysis of anhydrosugars in biomass burning aerosol particles from source samples.
Environmental science & technology, 2012Co-Authors: Xue F Sang, I. Gensch, W. Laumer, B. Kammer, Chuen Y. Chan, Guenter Engling, Andreas Wahner, Holger Wissel, Astrid Kiendler-scharrAbstract:A new method for stable carbon isotope ratio analysis of anhydrosugars from biomass burning aerosol particle source filter samples was developed by employing Thermal Desorption--2 Dimensional Gas Chromatography--Isotope Ratio Mass Spectrometry (TD-2DGC-IRMS). Compound specific isotopic measurements of Levoglucosan, mannosan, and galactosan performed by TD-2DGC-IRMS in a standard mixture show good agreement with isotopic measurements of the bulk anhydrosugars, carried out by Elemental Analyzer--Isotope Ratio Mass Spectrometry (EA-IRMS). The established method was applied to determine the isotope ratios of Levoglucosan, mannosan, and galactosan from source samples collected during combustion of hard wood, softwood, and crop residues. δ(13)C values of Levoglucosan were found to vary between -25.6 and -22.2‰, being higher in the case of softwood. Mannosan and galactosan were detected only in the softwood samples showing isotope ratios of -23.5‰ (mannosan) and -25.7‰ (galactosan). The isotopic composition of holocellulose in the plant material used for combustion experiments was determined with δ(13)C values between -28.5 and -23.7‰. The difference in δ(13)C of Levoglucosan in biomass burning aerosol particles compared to the parent fuel holocellulose was found to be -1.89 (±0.37)‰ for the investigated biomass fuels. Compound specific δ(13)C measurements of anhydrosugars should contribute to an improved source apportionment.
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chemical speciation transport and contribution of biomass burning smoke to ambient aerosol in guangzhou a mega city of china
Atmospheric Environment, 2010Co-Authors: Zhisheng Zhang, Guenter Engling, Chuanyao Lin, Charles C K Chou, Shihchun Candice Lung, Shihyu Chang, Shaojia Fan, Chuenyu Chan, Yuanhang ZhangAbstract:Abstract Intensive measurements of aerosol (PM 10 ) and associated water-soluble ionic and carbonaceous species were conducted in Guangzhou, a mega city of China, during summer 2006. Elevated levels of most chemical species were observed especially at nighttime during two episodes, characterized by dramatic build-up of the biomass burning tracers Levoglucosan and non-sea-salt potassium, when the prevailing wind direction had changed due to two approaching tropical cyclones. High-resolution air mass back trajectories based on the MM5 model revealed that air masses with high concentrations of Levoglucosan (43–473 ng m −3 ) and non-sea-salt potassium (0.83–3.2 μg m −3 ) had passed over rural regions of the Pearl River Delta and Guangdong Province, where agricultural activities and field burning of crop residues are common practices. The relative contributions of biomass burning smoke to organic carbon in PM 10 were estimated from Levoglucosan data to be on average 7.0 and 14% at daytime and nighttime, respectively, with maxima of 9.7 and 32% during the episodic transport events, indicating that biomass and biofuel burning activities in the rural parts of the Pearl River Delta and neighboring regions could have a significant impact on ambient urban aerosol levels.
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determination of Levoglucosan in biomass combustion aerosol by high performance anion exchange chromatography with pulsed amperometric detection
Atmospheric Environment, 2006Co-Authors: Guenter Engling, Jeffrey L Collett, Christian M Carrico, Sonia M Kreidenweis, William C Malm, Emily Lincoln, Yoshiteru Iinuma, Hartmut HerrmannAbstract:Abstract Atmospheric particulate matter can be strongly affected by smoke from biomass combustion, including wildfires, prescribed burns, and residential wood burning. Molecular source tracer techniques help determine contributions of biomass smoke to particle concentrations if representative source profiles are available. Various wood smoke source profiles have been generated for residential wood burning; however, few emission data are available for the combustion of biomass under open-burning conditions. Anhydrosugars, produced as thermal degradation products of cellulose and hemicellulose, are typically analyzed by gas chromatography-mass spectrometry (GC-MS) after chemical derivatization. A simpler alternative analytical method, based on high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), was developed here and utilized to measure several isomeric anhydrosugars (Levoglucosan, mannosan, and galactosan) in primary smoke aerosol from various types of biomass and from different combustion conditions representative of prescribed and wildfires. Highly varying patterns were observed in the emission profiles of various molecular markers as a function of fuel type and combustion conditions. Emission factors of Levoglucosan were a strong function of fuel type, combustion phase, and uphill versus downhill burn direction, varying from 36 to 1368 μg mg−1 organic carbon. Fuel type was the most important determinant, causing variations in emission factors of Levoglucosan over an order of magnitude, while combustion phase and burn direction generally affected emission factors by a factor of 2–3. Mannosan and galactosan showed emission trends similar to Levoglucosan. Levoglucosan emission factors from selected samples were compared to data obtained by two independent analytical methods, high-performance liquid chromatography (HPLC-MS) and GC-MS, showing rather good agreement. The HPAEC-PAD analytical method offers a simple alternative to GC-MS for future studies of aerosol concentrations of anhydrosugars, enabling more accurate estimates of contributions from biomass combustion to ambient particle concentrations.
Hartmut Herrmann - One of the best experts on this subject based on the ideXlab platform.
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atmospheric stability of Levoglucosan a detailed laboratory and modeling study
Environmental Science & Technology, 2010Co-Authors: Dirk Hoffmann, Yoshiteru Iinuma, Andreas Tilgner, Hartmut HerrmannAbstract:Levoglucosan, an important molecular marker for biomass burning, represents an important fraction of the water-soluble organic carbon in atmospheric particles influenced by residential wood burning and wildfires. However, particle phase oxidation processes of Levoglucosan by free radicals are not well-known. Hence, detailed kinetic studies on the reactivity of Levoglucosan with OH, NO3, and SO4− radicals in aqueous solutions were performed to better understand the Levoglucosan oxidation in the deliquescent particles. The data obtained were implemented into a parcel model with detailed microphysics and complex multiphase chemistry to investigate the degradation fluxes of Levoglucosan in cloud droplets and in deliquescent particles. The model calculations show that Levoglucosan can be oxidized readily by OH radicals during daytime with mean degradation fluxes of about 7.2 ng m−3 h−1 in summer and 4.7 ng m−3 h−1 in winter for a polluted continental plume. This indicates that the oxidation of Levoglucosan in ...
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determination of Levoglucosan in biomass combustion aerosol by high performance anion exchange chromatography with pulsed amperometric detection
Atmospheric Environment, 2006Co-Authors: Guenter Engling, Jeffrey L Collett, Christian M Carrico, Sonia M Kreidenweis, William C Malm, Emily Lincoln, Yoshiteru Iinuma, Hartmut HerrmannAbstract:Abstract Atmospheric particulate matter can be strongly affected by smoke from biomass combustion, including wildfires, prescribed burns, and residential wood burning. Molecular source tracer techniques help determine contributions of biomass smoke to particle concentrations if representative source profiles are available. Various wood smoke source profiles have been generated for residential wood burning; however, few emission data are available for the combustion of biomass under open-burning conditions. Anhydrosugars, produced as thermal degradation products of cellulose and hemicellulose, are typically analyzed by gas chromatography-mass spectrometry (GC-MS) after chemical derivatization. A simpler alternative analytical method, based on high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), was developed here and utilized to measure several isomeric anhydrosugars (Levoglucosan, mannosan, and galactosan) in primary smoke aerosol from various types of biomass and from different combustion conditions representative of prescribed and wildfires. Highly varying patterns were observed in the emission profiles of various molecular markers as a function of fuel type and combustion conditions. Emission factors of Levoglucosan were a strong function of fuel type, combustion phase, and uphill versus downhill burn direction, varying from 36 to 1368 μg mg−1 organic carbon. Fuel type was the most important determinant, causing variations in emission factors of Levoglucosan over an order of magnitude, while combustion phase and burn direction generally affected emission factors by a factor of 2–3. Mannosan and galactosan showed emission trends similar to Levoglucosan. Levoglucosan emission factors from selected samples were compared to data obtained by two independent analytical methods, high-performance liquid chromatography (HPLC-MS) and GC-MS, showing rather good agreement. The HPAEC-PAD analytical method offers a simple alternative to GC-MS for future studies of aerosol concentrations of anhydrosugars, enabling more accurate estimates of contributions from biomass combustion to ambient particle concentrations.
Alexandre Caseiro - One of the best experts on this subject based on the ideXlab platform.
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chemical characterisation of fine particle emissions from wood stove combustion of common woods growing in mid european alpine regions
Atmospheric Environment, 2008Co-Authors: Christoph Schmidl, Alexandre Caseiro, Anne Kaspergiebl, Petra Kotianova, Axel Erne, Heidi Aue, H PuxbaumAbstract:Woodsmoke samples derived from the combustion of beech, oak, spruce, larch and softwood briquettes in a closed stove have been collected and analysed so as to derive chemical profiles for ambient particulate matter (PM) source apportionment studies, for example, by CMB modelling. Trace metals, soluble ions, carbon species total carbon (TC), elemental carbon (EC) and organic carbon (OC), anhydrosugars, polar and non-polar trace organics, cellulose and humiclike substances (HULIS) have been measured. The inorganic and most organic components were not significantly different for the different woods, so that one profile could be derived for CMB modelling. The anhydrosugar Levoglucosan was present in high concentrations, 4–15% w/w, and for the mix of woods important for Austria, one conversion factor can be used to derive the mass of woodsmoke from the Levoglucosan concentration in ambient air. Mannosan is also a major component, 0.3–4% w/w, which, taken together with the Levoglucosan content, permits estimates to be made of the proportion of hard- and softwood smoke to ambient PM. r 2007 Elsevier Ltd. All rights reserved.
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determination of saccharides in atmospheric aerosol using anion exchange high performance liquid chromatography and pulsed amperometric detection
Journal of Chromatography A, 2007Co-Authors: Alexandre Caseiro, M Claeys, Iain L Marr, Anne Kaspergiebl, H PuxbaumAbstract:Abstract An improved method is described for the quantification of primary sugars, sugar alcohols and anhydrosugars in atmospheric aerosols, making use of separation by high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). Quartz fibre filters from high-volume samplers were extracted with water and the extract injected directly. Repeatability is typically 4% RSD, for e.g. Levoglucosan at 50 ng m−3 in air, better for winter levels around 700 ng m−3. Limits of detection for individual sugars are in the range 0.02–0.05 μg mL−1 in solution, corresponding to 2–5 ng m−3 from a 20 m3 air sample. The overlap of arabitol and levogluocosan is overcome by using a Dionex PA-1 column, with appropriate control of eluent composition, and peak deconvolution software, allowing quantification of both sugars in difficult summer samples containing low-levels of Levoglucosan. Analysis of a set of ambient aerosol samples by both GC-flame ionization detection and HPAEC-PAD shows good agreement. The new method has the advantage of requiring no sample pretreatment or derivatization and is thus well suited to handling large numbers of samples.