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Markku Kulmala - One of the best experts on this subject based on the ideXlab platform.
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modelling the influence of biotic plant stress on Atmospheric Aerosol particle processes throughout a growing season
Atmospheric Chemistry and Physics, 2021Co-Authors: Ditte Taipale, Velimatti Kerminen, Mikael Ehn, Markku Kulmala, Ulo NiinemetsAbstract:Abstract. Most trees emit volatile organic compounds (VOCs) continuously throughout their life, but the rate of emission, and spectrum of emitted VOCs, become substantially altered when the trees experience stress. Still, models to predict the emissions of VOCs do not account for perturbations caused by biotic plant stress. Considering that such stresses have generally been forecast to increase in both frequency and severity in future climate, the neglect of plant stress-induced emissions in models might be one of the key obstacles for realistic climate change predictions, since changes in VOC concentrations are known to greatly influence Atmospheric Aerosol processes. Thus, we constructed a model to study the impact of biotic plant stresses on new particle formation and growth throughout a full growing season. We simulated the influence on Aerosol processes caused by herbivory by European gypsy moth (Lymantria dispar) and autumnal moth (Epirrita autumnata) feeding on pedunculate oak (Quercus robur) and mountain birch (Betula pubescens var. pumila), respectively, and also fungal infections of pedunculate oak and balsam poplar (Populus balsamifera var. suaveolens) by oak powdery mildew (Erysiphe alphitoides) and poplar rust (Melampsora larici-populina), respectively. Our modelling results indicate that all the investigated plant stresses are capable of substantially perturbing both the number and size of Aerosol particles in Atmospherically relevant conditions, with increases in the amount of newly formed particles by up to about one order of magnitude and additional daily growth of up to almost 50 nm. We also showed that it can be more important to account for biotic plant stresses in models than significant variations in e.g. leaf area index, and temperature and light conditions, which are currently the main parameters controlling predictions of VOC emissions. Our study, thus, demonstrates that biotic plant stress can be highly Atmospherically relevant and it supports biotic plant stress emissions to be integrated into numerical models for prediction of Atmospheric chemistry and physics, including climate change projection models.
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direct observations of Atmospheric Aerosol nucleation
Science, 2013Co-Authors: Markku Kulmala, Katrianne Lehtipalo, Tuomo Nieminen, Jenni Kontkanen, Heikki Junninen, H E Manninen, Tuukka Petaja, Mikko Sipila, Siegfried SchobesbergerAbstract:Atmospheric nucleation is the dominant source of Aerosol particles in the global atmosphere and an important player in Aerosol climatic effects. The key steps of this process occur in the sub–2-nanometer (nm) size range, in which direct size-segregated observations have not been possible until very recently. Here, we present detailed observations of Atmospheric nanoparticles and clusters down to 1-nm mobility diameter. We identified three separate size regimes below 2-nm diameter that build up a physically, chemically, and dynamically consistent framework on Atmospheric nucleation—more specifically, Aerosol formation via neutral pathways. Our findings emphasize the important role of organic compounds in Atmospheric Aerosol formation, subsequent Aerosol growth, radiative forcing and associated feedbacks between biogenic emissions, clouds, and climate.
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Measurement of the nucleation of Atmospheric Aerosol particles
Nature Protocols, 2012Co-Authors: Markku Kulmala, Katrianne Lehtipalo, Tuomo Nieminen, Heikki Junninen, H E Manninen, Tuukka Petaja, Mikko Sipila, Miikka Dal Maso, Pasi P Aalto, Pauli PaasonenAbstract:The formation of new Atmospheric Aerosol particles and their subsequent growth have been observed frequently at various locations all over the world. The Atmospheric nucleation rate (or formation rate) and growth rate (GR) are key parameters to characterize the phenomenon. Recent progress in measurement techniques enables us to measure Atmospheric nucleation at the size (mobility diameter) of 1.5 (±0.4) nm. The detection limit has decreased from 3 to 1 nm within the past 10 years. In this protocol, we describe the procedures for identifying new-particle-formation (NPF) events, and for determining the nucleation, formation and growth rates during such events under Atmospheric conditions. We describe the present instrumentation, best practices and other tools used to investigate Atmospheric nucleation and NPF at a certain mobility diameter (1.5, 2.0 or 3.0 nm). The key instruments comprise devices capable of measuring the number concentration of the formed nanoparticles and their size, such as a suite of modern condensation particle counters (CPCs) and air ion spectrometers, and devices for characterizing the pre-existing particle number concentration distribution, such as a differential mobility particle sizer (DMPS). We also discuss the reliability of the methods used and requirements for proper measurements and data analysis. The time scale for realizing this procedure is 1 year.
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aliphatic and aromatic amines in Atmospheric Aerosol particles comparison of three ionization techniques in liquid chromatography mass spectrometry and method development
Talanta, 2012Co-Authors: Jose Ruizjimenez, Markku Kulmala, Tuukka Petaja, Sanna Hautala, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa RiekkolaAbstract:Abstract A complete methodology was developed for the determination of ten aliphatic and nine aromatic amines in Atmospheric Aerosol particles. Before the liquid chromatography — tandem mass spectrometric separation and determination, the derivatization reaction of the analytes using dansyl chloride was accelerated by ultrasounds. From three different ionization techniques studied electrospray ionization was superior in terms of sensitivity, linearity, repeatability and reproducibility over Atmospheric pressure chemical ionization and photoionization for the target analytes. The method developed was validated for the gas phase, 30 nm and total suspended Atmospheric Aerosol particles. The method quantification limits ranged between 1.8 and 71.7 pg. The accuracy and the potential matrix effects were evaluated using a standard addition methodology. Recoveries from 92.1% to 109.1%, the repeatability from 0.6% to 8.4% and the reproducibility from 2.3% to 9.8% were obtained. The reliability of the methodology was proved by the statistical evaluation. Finally, the developed methodology was applied to the determination of the target analytes in eight size separated ultrafine particulate (Dp=30±4 nm) samples and in eight total suspended particulate samples collected at the SMEAR II station. The mean concentrations for aliphatic amines were between 0.01 and 42.67 ng m−3 and for aromatic amines between 0.02 and 1.70 ng m−3. Thirteen amines were quantified for the first time in 30 nm Aerosol particles.
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a complete methodology for the reliable collection sample preparation separation and determination of organic compounds in ultrafine 30 nm 40 nm and 50 nm Atmospheric Aerosol particles
Analytical Methods, 2011Co-Authors: Jose Ruizjimenez, Tuukka Petaja, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa Riekkola, Aki Virkkula, Markku KulmalaAbstract:A complete reliable methodology including several extraction and chromatographic techniques has been developed for the determination of selected organic compounds in Atmospheric Aerosol particles. Size separated ultrafine particles (Dp ≤ 50nm) and total suspended particles (TSP) were collected in a urban and forest environment. One third of the samples contained TS particles and the rest of the samples were size-separated (30, 40 or 50 nm particles) with a differential mobility analyzer (DMA). Gas chromatography-mass spectrometric and liquid chromatography-mass spectrometric methods were developed for the analysis of the target compounds and the sample pretreatment was shortened by exploiting ultrasonic energy. The investigated compounds included seven amines (average concentrations ranged between 0.1 and 10.9 ng m−3), eight aldehydes (0.1–11.9 ng m−3), two polyols (0.1–81.5 ng m−3) and sixteen acids (0.1–47.2 ng m−3). The whole methodology including sample preparation and analysis methods was carefully validated by comparison of the results obtained with those provided by a conventional extraction method, non-assisted by ultrasound and by standard addition methodology, respectively. There were clear differences, up to two orders of magnitude, in the concentrations of the target compounds in Aerosol samples with different sizes collected from an urban and forest environment.
Marjaliisa Riekkola - One of the best experts on this subject based on the ideXlab platform.
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aliphatic and aromatic amines in Atmospheric Aerosol particles comparison of three ionization techniques in liquid chromatography mass spectrometry and method development
Talanta, 2012Co-Authors: Jose Ruizjimenez, Markku Kulmala, Tuukka Petaja, Sanna Hautala, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa RiekkolaAbstract:Abstract A complete methodology was developed for the determination of ten aliphatic and nine aromatic amines in Atmospheric Aerosol particles. Before the liquid chromatography — tandem mass spectrometric separation and determination, the derivatization reaction of the analytes using dansyl chloride was accelerated by ultrasounds. From three different ionization techniques studied electrospray ionization was superior in terms of sensitivity, linearity, repeatability and reproducibility over Atmospheric pressure chemical ionization and photoionization for the target analytes. The method developed was validated for the gas phase, 30 nm and total suspended Atmospheric Aerosol particles. The method quantification limits ranged between 1.8 and 71.7 pg. The accuracy and the potential matrix effects were evaluated using a standard addition methodology. Recoveries from 92.1% to 109.1%, the repeatability from 0.6% to 8.4% and the reproducibility from 2.3% to 9.8% were obtained. The reliability of the methodology was proved by the statistical evaluation. Finally, the developed methodology was applied to the determination of the target analytes in eight size separated ultrafine particulate (Dp=30±4 nm) samples and in eight total suspended particulate samples collected at the SMEAR II station. The mean concentrations for aliphatic amines were between 0.01 and 42.67 ng m−3 and for aromatic amines between 0.02 and 1.70 ng m−3. Thirteen amines were quantified for the first time in 30 nm Aerosol particles.
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a complete methodology for the reliable collection sample preparation separation and determination of organic compounds in ultrafine 30 nm 40 nm and 50 nm Atmospheric Aerosol particles
Analytical Methods, 2011Co-Authors: Jose Ruizjimenez, Tuukka Petaja, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa Riekkola, Aki Virkkula, Markku KulmalaAbstract:A complete reliable methodology including several extraction and chromatographic techniques has been developed for the determination of selected organic compounds in Atmospheric Aerosol particles. Size separated ultrafine particles (Dp ≤ 50nm) and total suspended particles (TSP) were collected in a urban and forest environment. One third of the samples contained TS particles and the rest of the samples were size-separated (30, 40 or 50 nm particles) with a differential mobility analyzer (DMA). Gas chromatography-mass spectrometric and liquid chromatography-mass spectrometric methods were developed for the analysis of the target compounds and the sample pretreatment was shortened by exploiting ultrasonic energy. The investigated compounds included seven amines (average concentrations ranged between 0.1 and 10.9 ng m−3), eight aldehydes (0.1–11.9 ng m−3), two polyols (0.1–81.5 ng m−3) and sixteen acids (0.1–47.2 ng m−3). The whole methodology including sample preparation and analysis methods was carefully validated by comparison of the results obtained with those provided by a conventional extraction method, non-assisted by ultrasound and by standard addition methodology, respectively. There were clear differences, up to two orders of magnitude, in the concentrations of the target compounds in Aerosol samples with different sizes collected from an urban and forest environment.
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solid phase extraction of organic compounds in Atmospheric Aerosol particles collected with the particle into liquid sampler and analysis by liquid chromatography mass spectrometry
Talanta, 2010Co-Authors: Jevgeni Parshintsev, Markku Kulmala, Kari Hartonen, Tuulia Hyotylainen, Marjaliisa RiekkolaAbstract:Abstract Atmospheric Aerosol particles, collected with the particle-into-liquid sampler at SMEARII station in Finland in mid-August 2007, were analysed for biogenic acids. The sample pretreatment method, comprising solid-phase extraction with anion exchange and hydrophilic–lipophilic balance materials, was optimized. Extraction efficiencies of solid-phase extraction from 10 and 20 ml samples were about 100%, with average relative standard deviation of 8.9%, in concentration range from 12.5 to 50 ng/ml of the acid. Extraction of aldehydes was less successful, with efficiencies from 69 to 163% and average 10% deviation. Pretreated samples were analysed by reversed phase high performance liquid chromatography with ion trap mass spectrometric detection. Limits of detection achieved for organic acids with the analytical procedure developed ranged from 9 to 27 μg/l of extracted sample, while limits of quantitation were from 31 to 90 μg/l. Oxidation with ozone was used for the preparation of the acid of β-caryophyllene (β-caryophyllinic acid), which was also studied in Aerosol samples. MS 2 experiments were used to confirm the identification of trans -pinic, trans -pinonic and β-caryophyllinic acids. Azelaic, hexadecanoic, cis -pinonic, and cis - and trans -pinic acids were quantitated in the samples with use of authentic standards, while the concentrations of trans -pinonic and β-caryophyllinic acids were determined with cis -pinonic acid as surrogate. Also, the contribution of β-caryophyllene oxidation products to Aerosol organic carbon was evaluated. Aldehydes could not be analysed in real samples due to the insufficient extraction. The particle-into-liquid sampler proved to be suitable for the collection of Aerosol particles for the elucidation of daily and diurnal variation of selected species. The optimized sample pretreatment, together with the analysis method, offer a promising approach for the study of Aerosol chemical composition, where artifact formation is minimal and time resolution is good.
Xuguang Chi - One of the best experts on this subject based on the ideXlab platform.
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long term observations of Atmospheric Aerosol cloud condensation nuclei concentration and hygroscopicity in the amazon rain forest part 1 size resolved characterization and new model parameterizations for ccn prediction
Atmospheric Chemistry and Physics, 2016Co-Authors: Mira L Pohlker, Thomas Klimach, Joel Brito, Samara Carbone, Yafang Cheng, C. Pöhlker, Isabella Hrabe De Angelis, Henrique M J Barbosa, Xuguang ChiAbstract:Size-resolved long-term measurements of Atmospheric Aerosol and cloud condensation nuclei (CCN) concentrations as well as hygroscopicity were conducted at the remote Amazon Tall Tower Observatory (ATTO) in the central Amazon Basin over a one-year period and full seasonal cycle (March 2014 - February 2015). The presented measurements provide a climatology of CCN properties for a characteristic central Amazonian rain forest site. The CCN measurements were continuously cycled through 10 levels of supersaturation (S = 0.11 to 1.10 %) and span the Aerosol particle size range from 20 to 245 nm. The observed mean critical diameters of CCN activation range from 43 nm at S = 1.10 % to 172 nm at S = 0.11 %. The particle hygroscopicity exhibits a pronounced size dependence with lower values for the Aitken mode (κAit = 0.14 ± 0.03), elevated values for the accumulation mode (κAcc = 0.22 ± 0.05), and an overall mean value of κmean = 0.17 ± 0.06, consistent with high fractions of organic Aerosol. The hygroscopicity parameter κ exhibits remarkably little temporal variability: no pronounced diurnal cycles, weak seasonal trends, and few short-term variations during long-range transport events. In contrast, the CCN number concentrations exhibit a pronounced seasonal cycle, tracking the pollution-related seasonality in total Aerosol concentration. We find that the variability in the CCN concentrations in the central Amazon is mostly driven by Aerosol particle number concentration and size distribution, while variations in Aerosol hygroscopicity and chemical composition matter only during a few episodes. For modelling purposes, we compare different approaches of predicting CCN number concentration and present a novel parameterization, which allows accurate CCN predictions based on a small set of input data.
Tuukka Petaja - One of the best experts on this subject based on the ideXlab platform.
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direct observations of Atmospheric Aerosol nucleation
Science, 2013Co-Authors: Markku Kulmala, Katrianne Lehtipalo, Tuomo Nieminen, Jenni Kontkanen, Heikki Junninen, H E Manninen, Tuukka Petaja, Mikko Sipila, Siegfried SchobesbergerAbstract:Atmospheric nucleation is the dominant source of Aerosol particles in the global atmosphere and an important player in Aerosol climatic effects. The key steps of this process occur in the sub–2-nanometer (nm) size range, in which direct size-segregated observations have not been possible until very recently. Here, we present detailed observations of Atmospheric nanoparticles and clusters down to 1-nm mobility diameter. We identified three separate size regimes below 2-nm diameter that build up a physically, chemically, and dynamically consistent framework on Atmospheric nucleation—more specifically, Aerosol formation via neutral pathways. Our findings emphasize the important role of organic compounds in Atmospheric Aerosol formation, subsequent Aerosol growth, radiative forcing and associated feedbacks between biogenic emissions, clouds, and climate.
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Measurement of the nucleation of Atmospheric Aerosol particles
Nature Protocols, 2012Co-Authors: Markku Kulmala, Katrianne Lehtipalo, Tuomo Nieminen, Heikki Junninen, H E Manninen, Tuukka Petaja, Mikko Sipila, Miikka Dal Maso, Pasi P Aalto, Pauli PaasonenAbstract:The formation of new Atmospheric Aerosol particles and their subsequent growth have been observed frequently at various locations all over the world. The Atmospheric nucleation rate (or formation rate) and growth rate (GR) are key parameters to characterize the phenomenon. Recent progress in measurement techniques enables us to measure Atmospheric nucleation at the size (mobility diameter) of 1.5 (±0.4) nm. The detection limit has decreased from 3 to 1 nm within the past 10 years. In this protocol, we describe the procedures for identifying new-particle-formation (NPF) events, and for determining the nucleation, formation and growth rates during such events under Atmospheric conditions. We describe the present instrumentation, best practices and other tools used to investigate Atmospheric nucleation and NPF at a certain mobility diameter (1.5, 2.0 or 3.0 nm). The key instruments comprise devices capable of measuring the number concentration of the formed nanoparticles and their size, such as a suite of modern condensation particle counters (CPCs) and air ion spectrometers, and devices for characterizing the pre-existing particle number concentration distribution, such as a differential mobility particle sizer (DMPS). We also discuss the reliability of the methods used and requirements for proper measurements and data analysis. The time scale for realizing this procedure is 1 year.
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aliphatic and aromatic amines in Atmospheric Aerosol particles comparison of three ionization techniques in liquid chromatography mass spectrometry and method development
Talanta, 2012Co-Authors: Jose Ruizjimenez, Markku Kulmala, Tuukka Petaja, Sanna Hautala, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa RiekkolaAbstract:Abstract A complete methodology was developed for the determination of ten aliphatic and nine aromatic amines in Atmospheric Aerosol particles. Before the liquid chromatography — tandem mass spectrometric separation and determination, the derivatization reaction of the analytes using dansyl chloride was accelerated by ultrasounds. From three different ionization techniques studied electrospray ionization was superior in terms of sensitivity, linearity, repeatability and reproducibility over Atmospheric pressure chemical ionization and photoionization for the target analytes. The method developed was validated for the gas phase, 30 nm and total suspended Atmospheric Aerosol particles. The method quantification limits ranged between 1.8 and 71.7 pg. The accuracy and the potential matrix effects were evaluated using a standard addition methodology. Recoveries from 92.1% to 109.1%, the repeatability from 0.6% to 8.4% and the reproducibility from 2.3% to 9.8% were obtained. The reliability of the methodology was proved by the statistical evaluation. Finally, the developed methodology was applied to the determination of the target analytes in eight size separated ultrafine particulate (Dp=30±4 nm) samples and in eight total suspended particulate samples collected at the SMEAR II station. The mean concentrations for aliphatic amines were between 0.01 and 42.67 ng m−3 and for aromatic amines between 0.02 and 1.70 ng m−3. Thirteen amines were quantified for the first time in 30 nm Aerosol particles.
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a complete methodology for the reliable collection sample preparation separation and determination of organic compounds in ultrafine 30 nm 40 nm and 50 nm Atmospheric Aerosol particles
Analytical Methods, 2011Co-Authors: Jose Ruizjimenez, Tuukka Petaja, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa Riekkola, Aki Virkkula, Markku KulmalaAbstract:A complete reliable methodology including several extraction and chromatographic techniques has been developed for the determination of selected organic compounds in Atmospheric Aerosol particles. Size separated ultrafine particles (Dp ≤ 50nm) and total suspended particles (TSP) were collected in a urban and forest environment. One third of the samples contained TS particles and the rest of the samples were size-separated (30, 40 or 50 nm particles) with a differential mobility analyzer (DMA). Gas chromatography-mass spectrometric and liquid chromatography-mass spectrometric methods were developed for the analysis of the target compounds and the sample pretreatment was shortened by exploiting ultrasonic energy. The investigated compounds included seven amines (average concentrations ranged between 0.1 and 10.9 ng m−3), eight aldehydes (0.1–11.9 ng m−3), two polyols (0.1–81.5 ng m−3) and sixteen acids (0.1–47.2 ng m−3). The whole methodology including sample preparation and analysis methods was carefully validated by comparison of the results obtained with those provided by a conventional extraction method, non-assisted by ultrasound and by standard addition methodology, respectively. There were clear differences, up to two orders of magnitude, in the concentrations of the target compounds in Aerosol samples with different sizes collected from an urban and forest environment.
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Atmospheric data over a solar cycle no connection between galactic cosmic rays and new particle formation
Atmospheric Chemistry and Physics, 2009Co-Authors: Markku Kulmala, Tuomo Nieminen, Pauli Paasonen, Ilona Riipinen, Mira Hulkkonen, Larisa Sogacheva, H E Manninen, Tuukka PetajaAbstract:Abstract. Aerosol particles affect the Earth's radiative balance by directly scattering and absorbing solar radiation and, indirectly, through their activation into cloud droplets. Both effects are known with considerable uncertainty only, and translate into even bigger uncertainties in future climate predictions. More than a decade ago, variations in galactic cosmic rays were suggested to closely correlate with variations in Atmospheric cloud cover and therefore constitute a driving force behind Aerosol-cloud-climate interactions. Later, the enhancement of Atmospheric Aerosol particle formation by ions generated from cosmic rays was proposed as a physical mechanism explaining this correlation. Here, we report unique observations on Atmospheric Aerosol formation based on measurements at the SMEAR II station, Finland, over a solar cycle (years 1996–2008) that shed new light on these presumed relationships. Our analysis shows that none of the quantities related to Aerosol formation correlates with the cosmic ray-induced ionisation intensity (CRII). We also examined the contribution of ions to new particle formation on the basis of novel ground-based and airborne observations. A consistent result is that ion-induced formation contributes typically significantly less than 10% to the number of new particles, which would explain the missing correlation between CRII and Aerosol formation. Our main conclusion is that galactic cosmic rays appear to play a minor role for Atmospheric Aerosol formation events, and so for the connected Aerosol-climate effects as well.
Jevgeni Parshintsev - One of the best experts on this subject based on the ideXlab platform.
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aliphatic and aromatic amines in Atmospheric Aerosol particles comparison of three ionization techniques in liquid chromatography mass spectrometry and method development
Talanta, 2012Co-Authors: Jose Ruizjimenez, Markku Kulmala, Tuukka Petaja, Sanna Hautala, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa RiekkolaAbstract:Abstract A complete methodology was developed for the determination of ten aliphatic and nine aromatic amines in Atmospheric Aerosol particles. Before the liquid chromatography — tandem mass spectrometric separation and determination, the derivatization reaction of the analytes using dansyl chloride was accelerated by ultrasounds. From three different ionization techniques studied electrospray ionization was superior in terms of sensitivity, linearity, repeatability and reproducibility over Atmospheric pressure chemical ionization and photoionization for the target analytes. The method developed was validated for the gas phase, 30 nm and total suspended Atmospheric Aerosol particles. The method quantification limits ranged between 1.8 and 71.7 pg. The accuracy and the potential matrix effects were evaluated using a standard addition methodology. Recoveries from 92.1% to 109.1%, the repeatability from 0.6% to 8.4% and the reproducibility from 2.3% to 9.8% were obtained. The reliability of the methodology was proved by the statistical evaluation. Finally, the developed methodology was applied to the determination of the target analytes in eight size separated ultrafine particulate (Dp=30±4 nm) samples and in eight total suspended particulate samples collected at the SMEAR II station. The mean concentrations for aliphatic amines were between 0.01 and 42.67 ng m−3 and for aromatic amines between 0.02 and 1.70 ng m−3. Thirteen amines were quantified for the first time in 30 nm Aerosol particles.
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a complete methodology for the reliable collection sample preparation separation and determination of organic compounds in ultrafine 30 nm 40 nm and 50 nm Atmospheric Aerosol particles
Analytical Methods, 2011Co-Authors: Jose Ruizjimenez, Tuukka Petaja, Jevgeni Parshintsev, Totti Laitinen, Kari Hartonen, Marjaliisa Riekkola, Aki Virkkula, Markku KulmalaAbstract:A complete reliable methodology including several extraction and chromatographic techniques has been developed for the determination of selected organic compounds in Atmospheric Aerosol particles. Size separated ultrafine particles (Dp ≤ 50nm) and total suspended particles (TSP) were collected in a urban and forest environment. One third of the samples contained TS particles and the rest of the samples were size-separated (30, 40 or 50 nm particles) with a differential mobility analyzer (DMA). Gas chromatography-mass spectrometric and liquid chromatography-mass spectrometric methods were developed for the analysis of the target compounds and the sample pretreatment was shortened by exploiting ultrasonic energy. The investigated compounds included seven amines (average concentrations ranged between 0.1 and 10.9 ng m−3), eight aldehydes (0.1–11.9 ng m−3), two polyols (0.1–81.5 ng m−3) and sixteen acids (0.1–47.2 ng m−3). The whole methodology including sample preparation and analysis methods was carefully validated by comparison of the results obtained with those provided by a conventional extraction method, non-assisted by ultrasound and by standard addition methodology, respectively. There were clear differences, up to two orders of magnitude, in the concentrations of the target compounds in Aerosol samples with different sizes collected from an urban and forest environment.
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solid phase extraction of organic compounds in Atmospheric Aerosol particles collected with the particle into liquid sampler and analysis by liquid chromatography mass spectrometry
Talanta, 2010Co-Authors: Jevgeni Parshintsev, Markku Kulmala, Kari Hartonen, Tuulia Hyotylainen, Marjaliisa RiekkolaAbstract:Abstract Atmospheric Aerosol particles, collected with the particle-into-liquid sampler at SMEARII station in Finland in mid-August 2007, were analysed for biogenic acids. The sample pretreatment method, comprising solid-phase extraction with anion exchange and hydrophilic–lipophilic balance materials, was optimized. Extraction efficiencies of solid-phase extraction from 10 and 20 ml samples were about 100%, with average relative standard deviation of 8.9%, in concentration range from 12.5 to 50 ng/ml of the acid. Extraction of aldehydes was less successful, with efficiencies from 69 to 163% and average 10% deviation. Pretreated samples were analysed by reversed phase high performance liquid chromatography with ion trap mass spectrometric detection. Limits of detection achieved for organic acids with the analytical procedure developed ranged from 9 to 27 μg/l of extracted sample, while limits of quantitation were from 31 to 90 μg/l. Oxidation with ozone was used for the preparation of the acid of β-caryophyllene (β-caryophyllinic acid), which was also studied in Aerosol samples. MS 2 experiments were used to confirm the identification of trans -pinic, trans -pinonic and β-caryophyllinic acids. Azelaic, hexadecanoic, cis -pinonic, and cis - and trans -pinic acids were quantitated in the samples with use of authentic standards, while the concentrations of trans -pinonic and β-caryophyllinic acids were determined with cis -pinonic acid as surrogate. Also, the contribution of β-caryophyllene oxidation products to Aerosol organic carbon was evaluated. Aldehydes could not be analysed in real samples due to the insufficient extraction. The particle-into-liquid sampler proved to be suitable for the collection of Aerosol particles for the elucidation of daily and diurnal variation of selected species. The optimized sample pretreatment, together with the analysis method, offer a promising approach for the study of Aerosol chemical composition, where artifact formation is minimal and time resolution is good.