scholarly journals Homogenous nucleation of sulfuric acid and water at close to atmospherically relevant conditions

2011 ◽  
Vol 11 (11) ◽  
pp. 5277-5287 ◽  
Author(s):  
D. Brus ◽  
K. Neitola ◽  
A.-P. Hyvärinen ◽  
T. Petäjä ◽  
J. Vanhanen ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Gas Phase ◽  
Acid Concentration ◽  
High Efficiency ◽  
Detection Efficiency ◽  
Sulfuric Acid Concentration ◽  
Ionization Mass ◽  
Atmospheric Measurements ◽  
Flow Tube ◽  
Particle Counter

Abstract. In this study the homogeneous nucleation rates in the system of sulfuric acid and water were measured by using a flow tube technique. The goal was to directly compare particle formation rates obtained from atmospheric measurements with nucleation rates of freshly nucleated particles measured with particle size magnifier (PSM) which has detection efficiency of unity for particles having mobility diameter of 1.5 nm. The gas phase sulfuric acid concentration in this study was measured with the chemical ionization mass spectrometer (CIMS), commonly used in field measurements. The wall losses of sulfuric acid were estimated from measured concentration profiles along the flow tube. The initial concentrations of sulfuric acid estimated from loss measurements ranged from 108 to 3 × 109 molecules cm−3. The nucleation rates obtained in this study cover about three orders of magnitude from 10−1 to 102 cm−3 s−1 for commercial ultrafine condensation particle counter (UCPC) TSI model 3025A and from 101 to 104 cm−3 s−1 for PSM. The nucleation rates and the slopes (dlnJ/dln [H2SO4]) show satisfactory agreement when compared to empirical kinetic and activation models and the latest atmospheric nucleation data. To the best of our knowledge, this is the first experimental work providing temperature dependent nucleation rate measurements using a high efficiency particle counter with a cut-off-size of 1.5 nm together with direct measurements of gas phase sulfuric acid concentration.

scholarly journals Homogenous nucleation of sulfuric acid and water at atmospherically relevant conditions

2010 ◽  
Vol 10 (11) ◽  
pp. 25959-25989 ◽  
Author(s):  
D. Brus ◽  
K. Neitola ◽  
T. Petäjä ◽  
J. Vanhanen ◽  
A.-P. Hyvärinen ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Detection Efficiency ◽  
Sulfuric Acid Concentration ◽  
Field Measurements ◽  
Ionization Mass ◽  
Atmospheric Measurements ◽  
Flow Tube ◽  
Measured Concentration ◽  
Condensation Particle Counter ◽  
Atmospheric Nucleation

Abstract. In this study the homogeneous nucleation rates of sulfuric acid and water were measured by using a flow tube technique. The goal was to directly compare particle formation rates obtained from atmospheric measurements with nucleation rates of freshly nucleated particles measured with particle size magnifier (PSM) which has detection efficiency of unity for particles having mobility diameter of 1.5 nm. The gas phase sulfuric acid concentration in this study was measured with the chemical ionization mass spectrometer (CIMS), commonly used in field measurements. The wall losses of sulfuric acid were estimated from measured concentration profiles along the flow tube. The initial concentrations of sulfuric acid estimated from loss measurements ranged from 108 to 3×109 molecules cm−3. The nucleation rates obtained in this study cover about three orders of magnitude from 10−1 to 102 cm3 s−1 for commercial ultrafine condensation particle counter (UCPC) TSI model 3025A and from 101 to 104 cm3 s−1 for PSM. The nucleation rates and the slopes (dlnJ/dln[H2SO4]) show satisfactory agreement when compared to empirical kinetic and activation models and the latest atmospheric nucleation data.

scholarly journals Sulfuric acid and OH concentrations in a boreal forest site

2009 ◽  
Vol 9 (19) ◽  
pp. 7435-7448 ◽  
Author(s):  
T. Petäjä ◽  
R. L. Mauldin, III ◽  
E. Kosciuch ◽  
J. McGrath ◽  
T. Nieminen ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Gas Phase ◽  
Acid Concentration ◽  
Sulfuric Acid Concentration ◽  
Particle Formation ◽  
Daily Maximum ◽  
Ionization Mass ◽  
Forest Site ◽  
Aerosol Formation ◽  
Atmospheric Particle

Abstract. As demonstrated in a number of investigations, gaseous sulfuric acid plays a central role in atmospheric aerosol formation. Using chemical ionization mass spectrometer the gas-phase sulfuric acid and OH concentration were measured in Hyytiälä, SMEAR II station, Southern Finland during 24 March to 28 June 2007. Clear diurnal cycles were observed as well as differences between new particle formation event days and non-event days. Typically, the daily maximum concentrations of gas phase sulfuric acid varied from 3×105 to 2×106 molec cm−3 between non-event and event days. Noon-time OH concentrations varied from 3-6×105 molec cm−3 and not a clear difference between event and non-events was detected. The measured time series were also used as a foundation to develop reasonable proxies for sulfuric acid concentration. The proxies utilized source and sink terms, and the simplest proxy is radiation times sulfur dioxide divided by condensation sink. Since it is still challenging to measure sulfuric acid in ambient concentrations, and due to its significant role in atmospheric particle formation, reasonable proxies are needed. We use all together three different proxies and one chemical box model and compared their results to the measured data. The proxies for the sulfuric acid concentration worked reasonably well, and will be used to describe sulfuric acid concentrations in SMEAR II station, when no measured sulfuric acid data is available. With caution the proxies could be applied to other environments as well.

scholarly journals Homogeneous nucleation of sulfuric acid and water mixture: experimental setup and first results

2009 ◽  
Vol 9 (6) ◽  
pp. 23875-23907
Author(s):  
D. Brus ◽  
A.-P. Hyvärinen ◽  
Y. Viisanen ◽  
M. Kulmala ◽  
H. Lihavainen
Keyword(s):  
Sulfuric Acid ◽  
Laminar Flow ◽  
Theoretical Prediction ◽  
Acid Concentration ◽  
Homogeneous Nucleation ◽  
Sulfuric Acid Concentration ◽  
Experimental Setup ◽  
Water Mixture ◽  
Flow Tube ◽  
First Results

Abstract. In this study we introduce a new laminar flow tube suitable for binary and ternary homogeneous nucleation studies. The production of sulfuric acid and water vapor mixture, the experimental setup and the method of sulfuric acid concentration determination are discussed in details. Wall losses were estimated from the measured sulfuric acid concentration profile along the laminar flow tube and compared to a theoretical prediction. In this investigation the experimental evidence of new particle formation was observed at concentration of 109 molecules of sulfuric acid in cm3 and nucleation rates measured at three relative humidities (RH) 10, 30 and 50% cover six orders of magnitudes from 10−3 to 103 particles in cm3. Particle free air was used as a carrier gas. Our first results are compared to theoretical prediction of binary homogeneous nucleation, to results obtained by other investigators and to atmospheric nucleation.

scholarly journals Sulfuric acid and OH concentrations in a boreal forest site

2008 ◽  
Vol 8 (6) ◽  
pp. 20193-20221
Author(s):  
T. Petäjä ◽  
R. L. Mauldin, III ◽  
E. Kosciuch ◽  
J. McGrath ◽  
T. Nieminen ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Gas Phase ◽  
Sulfuric Acid Concentration ◽  
Particle Formation ◽  
Daily Maximum ◽  
Ionization Mass ◽  
Forest Site ◽  
Aerosol Formation ◽  
Atmospheric Particle ◽  
Diurnal Cycles

Abstract. As demonstrated in a number of investigations, gaseous sulfuric acid plays a central role in atmospheric aerosol formation. Using chemical ionization mass spectrometer the gas-phase sulfuric acid and OH concentration were measured in Hyytiälä, SMEAR II station, Southern Finland during 24 March to 28 June 2007. Clear diurnal cycles were observed as well as differences between new particle formation event days and non-event days. The typical daily maximum concentrations of gas phase sulfuric acid varied from 3·105 to 2·106 molec cm−3 between non-event and event days. Noon-time OH concentrations varied from 3–6·105 molec cm−3 and not a clear difference between event and non-events was detected. Since it is still challenging to measure sulfuric acid, and due to its significant role in atmospheric particle formation, three different proxies and one chemical box model calculation were compared to the measured data. The proxies for the sulfuric acid concentration worked reasonably, and with caution, could be applied to other environments.

scholarly journals Homogeneous nucleation of sulfuric acid and water mixture: experimental setup and first results

2010 ◽  
Vol 10 (6) ◽  
pp. 2631-2641 ◽  
Author(s):  
D. Brus ◽  
A.-P. Hyvärinen ◽  
Y. Viisanen ◽  
M. Kulmala ◽  
H. Lihavainen
Keyword(s):  
Sulfuric Acid ◽  
Theoretical Prediction ◽  
Acid Concentration ◽  
Homogeneous Nucleation ◽  
Sulfuric Acid Concentration ◽  
Experimental Setup ◽  
Water Mixture ◽  
Flow Tube ◽  
Atmospheric Nucleation ◽  
First Results

Abstract. In this study we introduce a new flow tube suitable for binary and ternary homogeneous nucleation studies. The production of sulfuric acid and water vapor mixture, the experimental setup and the method of sulfuric acid concentration determination are discussed in detail. Wall losses were estimated from the measured sulfuric acid concentration profiles along the flow tube and compared to a theoretical prediction. In this investigation the experimental evidence of new particle formation was observed at a concentration of 109 molecules cm−3 of sulfuric acid and the nucleation rates measured at three relative humidities (RH) 10, 30 and 50%, cover six orders of magnitude, from 10−3 to 103 particles cm−3. Particle free air was used as a carrier gas. Our initial results are compared to the theoretical prediction of binary homogeneous nucleation, to results obtained by other investigators, and to atmospheric nucleation.

scholarly journals A proxy for atmospheric daytime gaseous sulfuric acid concentration in urban Beijing

2019 ◽  
Vol 19 (3) ◽  
pp. 1971-1983 ◽  
Author(s):  
Yiqun Lu ◽  
Chao Yan ◽  
Yueyun Fu ◽  
Yan Chen ◽  
Yiliang Liu ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Acid Concentration ◽  
Atmospheric Chemistry ◽  
Sulfuric Acid Concentration ◽  
Oh Radicals ◽  
Ionization Mass ◽  
Polluted Atmosphere ◽  
Long Time ◽  
Statistical Analysis Method ◽  
Relative Errors

Abstract. Gaseous sulfuric acid (H2SO4) is known as one of the key precursors for atmospheric new particle formation (NPF) processes, but its measurement remains challenging. Therefore, a proxy method that is able to derive gaseous sulfuric acid concentrations from parameters that can be measured relatively easily and accurately is highly desirable for the atmospheric chemistry community. Although such methods are available for clean atmospheric environments, a proxy that works well in a polluted atmosphere, such as that found in Chinese megacities, is yet to be developed. In this study, the gaseous sulfuric acid concentration was measured in February–March 2018, in urban Beijing using a nitrate based – long time-of-flight chemical ionization mass spectrometer (LToF-CIMS). A number of atmospheric parameters were recorded concurrently including the ultraviolet radiation B (UVB) intensity, the concentrations of O3, NOx (sum of NO and NO2), SO2, and HONO, and aerosol particle number size distributions. A proxy for atmospheric daytime gaseous sulfuric acid concentration was derived via a statistical analysis method using the UVB intensity, [SO2], the condensation sink (CS), [O3], and [HONO] (or [NOx]) as the predictor variables, where square brackets denote the concentrations of the corresponding species. In this proxy method, we considered the formation of gaseous sulfuric acid from reactions of SO2 and OH radicals during the daytime, and the loss of gaseous sulfuric acid due to its condensation onto the preexisting particles. In addition, we explored the formation of OH radicals from the conventional gas-phase photochemistry using O3 as a proxy and from the photolysis of HONO using HONO (and subsequently NOx) as a proxy. Our results showed that the UVB intensity and [SO2] are dominant factors in the production of gaseous sulfuric acid, and that the simplest proxy could be constructed with the UVB intensity and [SO2] alone. When the OH radical production from both homogenously and heterogeneously formed precursors were considered, the relative errors were reduced by up to 20 %.

scholarly journals A proxy for atmospheric daytime gaseous sulfuric acid concentration in urban Beijing

2018 ◽  
Author(s):  
Yiqun Lu ◽  
Chao Yan ◽  
Yueyun Fu ◽  
Yan Chen ◽  
Yiliang Liu ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Acid Concentration ◽  
Atmospheric Chemistry ◽  
Sulfuric Acid Concentration ◽  
Oh Radicals ◽  
Ionization Mass ◽  
Polluted Atmosphere ◽  
Long Time ◽  
Statistical Analysis Method ◽  
Chemistry Community

Abstract. Gaseous sulfuric acid is known as one of the key precursors for atmospheric new particle formation processes, but its measurement remains a major challenge. A proxy method that is able to derive gaseous sulfuric acid concentrations from parameters that can be measured relatively easily and accurately is therefore highly desirable among the atmospheric chemistry community. Although such methods are available for clean atmospheric environments, a proxy that works well in a polluted atmosphere, such as those in Chinese megacities, is yet to be developed. In this study, the gaseous sulfuric acid concentration was measured in February–March, 2018, in urban Beijing by a nitrate based – Long Time-of-Flight Chemical Ionization Mass Spectrometer (LToF-CIMS). A number of atmospheric parameters were recorded concurrently including the ultraviolet radiation B (UVB) intensity, concentrations of O3, NOx, SO2 and HONO, and aerosol particle number size distributions. A proxy for atmospheric daytime gaseous sulfuric acid concentration was derived using a statistical analysis method by using the UVB intensity, [SO2], condensation sink (CS), [O3], and [HONO] (or [NOx]) as the predictor variables. In this proxy method, we considered the formation of gaseous sulfuric acid from reactions of SO2 and OH radicals during the daytime, and loss of gaseous sulfuric acid due to its condensation onto the pre-existing particles. In addition, we explored formation of OH radicals from the conventional gas-phase photochemistry using ozone as a proxy and from the photolysis of heterogeneously-formed HONO using HONO (and subsequently NOx) as a proxy. Our results showed that the UVB intensity and [SO2] are dominant factors for the production of gaseous sulfuric acid, and that the simplest proxy could be constructed with the UVB intensity and [SO2] alone, resulting in up to 29 % relative deviations when sulfuric acid concentrations were larger than 2.0 × 106 molecules cm−3. When the OH radical production from both homogenously- and heterogeneously-formed precursors were considered, the relative deviations were lower than 24 %.

Sign in / Sign up

Export Citation Format

Share Document