Callback Service

Undefined

The world's leading PTR-MS company

Providing ultra-sensitive solutions for real-time trace gas analysis since 1998

Navigation

You are here

Scientific Articles - PTR-MS Bibliography

Welcome to the new IONICON scientific articles database!

Publications

Found 63 results
Title [ Year(Asc)]
Filters: First Letter Of Title is E  [Clear All Filters]
2016
[1734] VÄISÄNEN, TANELI., "Effects of Thermally Extracted Wood Distillates on the Characteristics of Wood-Plastic Composites", Academic Dissertation, no. 222, Eastern Finland University Library / Sales of publications P.O. Box 107, FI-80101 Joensuu, Finland, Publications of the University of Eastern Finland Dissertations in Forestry and Natural Sciences, 2016.
Link: http://epublications.uef.fi/pub/urn_isbn_978-952-61-2124-6/index_en.html
Abstract
<p>The use of raw materials derived from renewable sources is increasing due to the finiteness of crude oil reserves. In wood-plastic composites (WPCs), the plastic in a material is partially replaced by wood, which is an abundantly available and inexpensive raw material. WPCs are materials that encompass a wide range of performance levels such that they have diverse applications, e.g., in fencing and decking as well as in the manufacture of automobiles. The use of WPCs in indoor applications is also becoming increasingly popular. Despite the increasing popularity of WPCs, certain inherent limitations mean that these materials are unsuitable for some applications. Examples of the limitations associated with WPCs are their insufficient mechanical strength and their susceptibility to excess water absorption. Furthermore, the VOC (volatile organic compound) characteristics of WPCs have not been widely studied and therefore, a better understanding of these properties of WPCs would be of great importance. The properties of WPCs and their constituents can be altered by incorporating additives. However, some additives are rather expensive and their incorporation into WPCs is not straightforward. There is a clear need for novel, affordable and effective filler materials, especially those that would minimize the use of expensive constituents. Wood distillates are products originating from thermal processes where the components of wood are partly or completely decomposed into charcoal, condensable vapors, and non-condensable gases. Although the liquid components of wood have many potential applications, large volumes of liquids are still being discarded and not exploited in industrial applications. Thus, the incorporation of more of wood distillates into WPCs would enhance the use of raw materials and secondary products from the wood-processing industries. This would be both economically valuable and environmentally friendly since it would represent sustainable development by making commercial use of a potentially hazardous waste product. The main aim of this thesis was to investigate whether wood distillates could be used as WPC components. Another aim was to assess the possibility to improve the mechanical properties and water resistance of the WPCs with wood distillates. Furthermore, the applicability of proton-transfer-reaction time-of-flight massspectrometry (PTR-TOF-MS) in determining the VOC emission characteristics of WPCs was studied. The effects of incorporating hardwood and softwood distillates into WPCs were examined by characterizing the mechanical properties, water resistance and VOC emissions of these WPCs modified with the distillates. The distillate content varied from 1 wt% to 20 wt%. The suitability of PTR-TOF-MS for analyzing VOC emissions from WPCs was assessed by measuring VOC emissions from a WPC deck during a 41-day trial and comparing VOC emission rates between seven different WPC decks. Both hardwood and softwood distillates exerted positive effects on the water resistance of the WPC; the addition of hardwood distillate decreased the water absorption of the WPC by over 25% whereas at least a 16% decrease was observed for the WPC with the softwood distillate. Moreover, a 1 wt% addition of hardwood distillate into the WPC led to a highly significant increase (11.5%, p &lt; 0.01) in the tensile modulus as well as achieving minor enhancements in some other mechanical properties. Similarly, when 2 wt% of softwood was added to the WPC, a highly significant increase in the tensile strength (5.0%, p &lt; 0.01) was observed. Even though the addition of the distillates increased the total release of VOCs, the emission rates of harmful compounds, such as benzene, remained low. Nonetheless, the results from the VOC analyses indicated that some of the compounds investigated in this thesis may be smelled from the WPCs because their odor thresholds were exceeded. Wood distillates displayed good potential as natural additives in WPCs as they improved the mechanical properties and water resistance. The results of this thesis provide a basis for the further development of wood distillates as bio-based additives in WPCs</p>
2015
[1760] Seco, R., T. Karl, A. Guenther, K. P. Hosman, S. G. Pallardy, L. Gu, C. Geron, P. Harley, and S. Kim, "Ecosystem-scale volatile organic compound fluxes duringᅡᅠan extreme drought in a broadleaf temperate forestᅡᅠof the Missouri Ozarks (central USA)", Global Change Biology, vol. 21, pp. 3657–3674, Jul, 2015.
Link: http://dx.doi.org/10.1111/gcb.12980
Abstract
<p>Considerable amounts and varieties of biogenic volatile organic compounds (BVOCs) are exchanged between vegetation and the surrounding air. These BVOCs play key ecological and atmospheric roles that must be adequately represented for accurately modeling the coupled biosphere-atmosphere-climate earth system. One key uncertainty in existing models is the response of BVOC fluxes to an important global change process: drought. We describe the diurnal and seasonal variation in isoprene, monoterpene, and methanol fluxes from a temperate forest ecosystem before, during, and after an extreme 2012 drought event in the Ozark region of the central USA. BVOC fluxes were dominated by isoprene, which attained high emission rates of up to 35.4 mg m(-2) h(-1) at midday. Methanol fluxes were characterized by net deposition in the morning, changing to a net emission flux through the rest of the daylight hours. Net flux of CO2 reached its seasonal maximum approximately a month earlier than isoprenoid fluxes, which highlights the differential response of photosynthesis and isoprenoid emissions to progressing drought conditions. Nevertheless, both processes were strongly suppressed under extreme drought, although isoprene fluxes remained relatively high compared to reported fluxes from other ecosystems. Methanol exchange was less affected by drought throughout the season, confirming the complex processes driving biogenic methanol fluxes. The fraction of daytime (7-17 h) assimilated carbon released back to the atmosphere combining the three BVOCs measured was 2% of gross primary productivity (GPP) and 4.9% of net ecosystem exchange (NEE) on average for our whole measurement campaign, while exceeding 5% of GPP and 10% of NEE just before the strongest drought phase. The meganv2.1 model correctly predicted diurnal variations in fluxes driven mainly by light and temperature, although further research is needed to address model BVOC fluxes during drought events.</p>
[1624] Hu, L., D. B. Millet, M. Baasandorj, T. J. Griffis, K. R. Travis, C. W. Tessum, J. D. Marshall, W. F. Reinhart, T. Mikoviny, M. Müller, et al., "Emissions of C 6 -C 8 aromatic compounds in the United States: Constraints from tall tower and aircraft measurements", Journal of Geophysical Research: Atmospheres, vol. 120, pp. 826–842, Jan, 2015.
Link: http://dx.doi.org/10.1002/2014JD022627
Abstract
<p>We present two full years of continuous C6&ndash;C8 aromatic compound measurements by PTR-MS at the KCMP tall tower (Minnesota, US) and employ GEOS-Chem nested grid simulations in a Bayesian inversion to interpret the data in terms of new constraints on US aromatic emissions. Based on the tall tower data, we find that the RETRO inventory (year-2000) overestimates US C6&ndash;C8 aromatic emissions by factors of 2.0&ndash;4.5 during 2010&ndash;2011, likely due in part to post-2000 reductions. Likewise, our implementation of the US EPA&#39;s NEI08 overestimates the toluene flux by threefold, reflecting an inventory bias in non-road emissions plus uncertainties associated with species lumping. Our annual top-down emission estimates for benzene and C8 aromatics agree with the NEI08 bottom-up values, as does the inferred contribution from non-road sources. However, the NEI08 appears to underestimate on-road emissions of these compounds by twofold during the warm season. The implied aromatic sources upwind of North America are more than double the prior estimates, suggesting a substantial underestimate of East Asian emissions, or large increases there since 2000. Long-range transport exerts an important influence on ambient benzene over the US: on average 43% of its wintertime abundance in the US Upper Midwest is due to sources outside North America. Independent aircraft measurements show that the inventory biases found here for C6&ndash;C8 aromatics also apply to other parts of the US, with notable exceptions for toluene in California and Houston, Texas. Our best estimates of year-2011 contiguous US emissions are 206 (benzene), 408 (toluene), and 822 (C8 aromatics) GgC.</p>
[1794] Hu, L., D. B. Millet, M. Baasandorj, T. J. Griffis, K. R. Travis, C. W. Tessum, J. D. Marshall, W. F. Reinhart, T. Mikoviny, M. Müller, et al., "Emissions of C6–C8 aromatic compounds in the United States: Constraints from tall tower and aircraft measurements", Journal of Geophysical Research: Atmospheres, vol. 120, pp. 826–842, 2015.
Link: http://onlinelibrary.wiley.com/doi/10.1002/2014JD022627/abstract
Abstract
<p>We present two full years of continuous C6&ndash;C8 aromatic compound measurements by PTR-MS at the KCMP tall tower (Minnesota, US) and employ GEOS-Chem nested grid simulations in a Bayesian inversion to interpret the data in terms of new constraints on US aromatic emissions. Based on the tall tower data, we find that the RETRO inventory (year-2000) overestimates US C6&ndash;C8 aromatic emissions by factors of 2.0&ndash;4.5 during 2010&ndash;2011, likely due in part to post-2000 reductions. Likewise, our implementation of the US EPA&#39;s NEI08 overestimates the toluene flux by threefold, reflecting an inventory bias in non-road emissions plus uncertainties associated with species lumping. Our annual top-down emission estimates for benzene and C8 aromatics agree with the NEI08 bottom-up values, as does the inferred contribution from non-road sources. However, the NEI08 appears to underestimate on-road emissions of these compounds by twofold during the warm season. The implied aromatic sources upwind of North America are more than double the prior estimates, suggesting a substantial underestimate of East Asian emissions, or large increases there since 2000. Long-range transport exerts an important influence on ambient benzene over the US: on average 43% of its wintertime abundance in the US Upper Midwest is due to sources outside North America. Independent aircraft measurements show that the inventory biases found here for C6&ndash;C8 aromatics also apply to other parts of the US, with notable exceptions for toluene in California and Houston, Texas. Our best estimates of year-2011 contiguous US emissions are 206 (benzene), 408 (toluene), and 822 (C8 aromatics) GgC.</p>
[1637] Wood, E. C., B. W Knighton, E. C. Fortner, S. C. Herndon, T. B. Onasch, J. P. Franklin, D. R. Worsnop, T. R. Dallmann, D. R. Gentner, A. H. Goldstein, et al., "Ethylene glycol emissions from on-road vehicles.", Environ Sci Technol, vol. 49, pp. 3322–3329, Mar, 2015.
Link: http://dx.doi.org/10.1021/acs.est.5b00557
Abstract
<p>Ethylene glycol (HOCH2CH2OH), used as engine coolant for most on-road vehicles, is an intermediate volatility organic compound (IVOC) with a high Henry&#39;s law coefficient. We present measurements of ethylene glycol (EG) vapor in the Caldecott Tunnel near San Francisco, using a proton transfer reaction mass spectrometer (PTR-MS). Ethylene glycol was detected at mass-to-charge ratio 45, usually interpreted as solely coming from acetaldehyde. EG concentrations in bore 1 of the Caldecott Tunnel, which has a 4% uphill grade, were characterized by infrequent (approximately once per day) events with concentrations exceeding 10 times the average concentration, likely from vehicles with malfunctioning engine coolant systems. Limited measurements in tunnels near Houston and Boston are not conclusive regarding the presence of EG in sampled air. Previous PTR-MS measurements in urban areas may have overestimated acetaldehyde concentrations at times due to this interference by ethylene glycol. Estimates of EG emission rates from the Caldecott Tunnel data are unrealistically high, suggesting that the Caldecott data are not representative of emissions on a national or global scale. EG emissions are potentially important because they can lead to the formation of secondary organic aerosol following oxidation in the atmospheric aqueous phase.</p>
[1666] Yamada, H., S. Inomata, and H. Tanimoto, "Evaporative emissions in three-day diurnal breathing loss tests on passenger cars for the Japanese market", Atmospheric Environment, vol. 107, pp. 166–173, Apr, 2015.
Link: http://dx.doi.org/10.1016/j.atmosenv.2015.02.032
Abstract
<p>Breakthrough emissions that dominate diurnal evaporative emissions from gasoline vehicles were observed in continuous 3-day diurnal breathing loss (DBL) tests. These measurements were conducted on nine vehicles for the Japanese market. Two of these vehicles, made by US and European manufacturers, also meet regulations in their countries of origin. Four vehicles exhibited marked emissions caused by breakthrough emissions during the experimental period, all made by Japanese manufacturers. Using our experimental results, we estimate the total diurnal evaporative emissions from gasoline vehicles in Japan to be 32,792 t y&minus;1. The compositions of the breakthrough and permeation emissions were analyzed in real time using proton transfer reaction plus switchable reagent ion mass spectrometry to estimate the ozone formation potential for the evaporative emissions. The real-time measurements showed that the adsorption of hydrocarbons in a sealed housing evaporative determination unit can result in underestimation, when concentrations are only monitored before and after a DBL test. The composition analysis gave an estimated maximum incremental reactivity (MIR) 20% higher for the breakthrough emissions than for the gasoline that was tested, while the MIR for the permeation emissions was almost the same as the MIR for the fuel. Evaporative emissions from gasoline vehicles in Japan were found to contribute 4.2% to emissions from stationary sources using a mass-based estimate, or 6.1% of emissions from stationary sources using a MIR-based estimate.</p>
[1678] Colard, S., G. O'Connell, P. Sulzer, K. Breiev, X. Cahours, and S. S. Biel, "An Experimental Method to Determine the Concentration of Nicotine in Exhaled Breath and its Retention Rate Following Use of an Electronic Cigarette", J Environ Anal Chem, vol. 02, 2015.
Link: http://dx.doi.org/10.4172/2380-2391.1000161
Abstract
<p>An experimental method is presented for the first time to determine the concentration of nicotine in exhaled breath following e-cigarette use in experienced participants and the impact that vaping topography has on the retention rate of nicotine. Aerosols from e-cigarettes containing different concentrations of nicotine were first evaluated by GC-FID to determine the concentration of nicotine delivered per puff versus machine - vaping intensity. These e-cigarettes were then vaped by participants through a cigarette holder attached to a smoking topography analyzer which recorded puff volume and puff duration. This allowed the concentration of nicotine in the aerosol inhaled by the participant during each puff to be determined. A PTR-MS instrument was then used to determine the concentration of nicotine exhaled following each use of the e-cigarette. By dividing this figure by the nicotine concentration delivered enabled its retention rate to be calculated. The principal finding was over 99% of the nicotine was retained by the participants when the e-cigarette aerosol was inhaled and a reduced but still substantial quantity was retained (on average 86%) when the e-cigarette aerosol was held in the mouth only (i.e, no inhalation). In both cases, the nicotine concentrations detected in the exhaled breath were low (range 1.8 - 1786 ppb). The experimental method presented here may be used to determine the concentration of other e-cigarette aerosol constituents in exhaled breath and the retention rate of those constituents which is useful for the evaluation of e-cigarettes from a consumer and bystander perspective.</p>
2014
[1549] Karl, T., L. Kaser, and A. Turnipseed, "Eddy covariance measurements of isoprene and 232-MBO based on NO+ time-of-flight mass spectrometry", International Journal of Mass Spectrometry, vol. 365-366, pp. 15 - 19, 2014.
Link: http://www.sciencedirect.com/science/article/pii/S1387380613004272
Abstract
<div>Isoprene and 2-methyl-3-buten-2-ol (232-MBO) are the dominant</div> <div>biogenic \{VOCs\} released throughout the US, thus requiring simultaneous</div> <div>measurements. Recent measurements suggest the presence of isoprene</div> <div>in 232-MBO dominated ecosystems, however analytical difficulties</div> <div>make it problematic to detect both species independently. Based on</div> <div>a new chemical ionization scheme we use eddy covariance measurements</div> <div>to selectively measure fluxes of both species without analytical</div> <div>interference at the Manitou Experimental Forest (MEF) in Colorado.</div> <div>Our measurements show a concentration ratio between isoprene and</div> <div>232 \{MBO\} of 0.24 (ppbv/ppbv), and a flux ratio of 0.10 ([ppbv m/s]/[ppbv m/s]).</div> <div>Daytime average emission factors of isoprene and 232 \{MBO\} were</div> <div>1.4 +/- 0.3 and 16.0 +/- &nbsp;3.0 mg/m^2/h respectively.</div> <div>Both compounds exhibit light and temperature dependent fluxes. These</div> <div>findings suggest that isoprene is both locally produced and transported</div> <div>to the measurement site dominated by ponderosa pine. This makes it</div> <div>difficult to use \{MVK\} and \{MAC\} as tracers for estimating the</div> <div>photochemical age of isoprene chemistry at this site. Further our</div> <div>measurements suggest that isoprene can contribute to about 15% of</div> <div>the \{OH\} reactivity relative to 232 MBO.</div>
[1528] Zardini, A. A., S. M. Platt, M. Clairotte, I. El Haddad, B. Temime, N. Marchand, I. Jezek, L. Drinovec, G. Mocnik, J. G. Slowik, et al., "Effects of alkylate fuel on exhaust emissions and secondary aerosol formation of a 2- stroke and a 4-stroke scooter", Atmospheric Environment, Mar, 2014.
Link: http://dx.doi.org/10.1016/j.atmosenv.2014.03.024
Abstract
<p>Regulated and unregulated emissions from a 2-stroke and a 4-stroke scooter were characterized during a legislative driving cycle in a certified laboratory. Scooter exhaust was analyzed at the tailpipe, in a dilution tunnel, and partly collected in a mobile smog chamber for photochemical ageing. We present evidence that the photochemically aged exhaust from a 2-stroke and a 4-stroke scooter produces considerable amounts of secondary organic aerosol: from 1.5 to 22.0 mg/km, and from 5.5 to 6.6 mg/km, respectively. Tests were repeated after replacing the standard petrol and synthetic lube oil with an alkylate fuel (with low content of aromatic compounds) and ultra-clean lube oil (low ash forming potential). We observed emission reduction (with some exceptions) for several gaseous and particulate phase species, in particular for carbon monoxide (from 8% up to 38% and from 31% to 50%, for the 2-stroke and the 4-stroke scooters, respectively), particulate mass (from 32% up to 75% for the 2-stroke scooter), aromatic compounds (89% and 97% for the 2-stroke and the 4-stroke scooter, respectively), and secondary organic aerosol (from 87% to 100% and 99% for the 2-stroke and the 4-stroke scooters, respectively). We attribute the organic aerosol reduction to the absence of aromatics in the alkylate fuel.</p>
[1601] Liu, D., M. Marie Løkke, A. Leegaard Riis, K. Mortensen, and A. Feilberg, "Evaluation of clay aggregate biotrickling filters for treatment of gaseous emissions from intensive pig production.", J Environ Manage, vol. 136, pp. 1–8, Apr, 2014.
Link: http://dx.doi.org/10.1016/j.jenvman.2014.01.023
Abstract
<p>Treatment of ventilation air from livestock production by biological airfiltration has emerged as a cost-effective technology for reduction of emissions of odorants and ammonia. Volatile sulfur compounds from livestock production include H2S and methanethiol, which have been identified as potentially important odorants that are not removed sufficiently by biological air filters. Light-expanded clay aggregates (Leca(&reg;)) is a biotrickling filter material that contains iron oxides, which can oxidize H2S and methanethiol, and thus potentially may help to remove these two compounds in biological air filters. This study used on-line PTR-MS measurements to investigate the performances of two Leca(&reg;) biotrickling filters (abraded Leca(&reg;) filter and untreated Leca(&reg;) filter) for removal of odorants and ammonia emitted from an experimental pig house. The results indicated that the abraded Leca(&reg;) filter had a similar or slightly better capability for removing odorants than the untreated Leca(&reg;) filter. This may be due to the enlargement of the surface area by the friction process. The volatile sulfur compounds, however, were not removed efficiently by either of the two Leca(&reg;) filters. Kinetic analysis of a ventilation controlled experiment during the first period indicated that Grau second-order kinetics could be applied to analyze the removal of sulfur compounds and other odorants, whereas the Stover-Kincannon model could only be applied to analyze the removal of odorants other than sulfur compounds, partly due to the limitation of mass transfer of these compounds in the biotrickling filters. In the last measurement period, a production of dimethyl disulfide and dimethyltrisulfide coinciding with strongly enhanced removal of methanethiol was observed for the untreated filter. This was assumed to be enhanced by an incidence of low local air velocity in the filter and indicated involvement of iron-catalyzed reactions in the removal of sulfur compounds.</p>
[1526] Gloess, A. N., A. Vietri, F. Wieland, S. Smrke, B. Schönbächler, J. A. Sanchez Lopez, S. Petrozzi, S. Bongers, T. Koziorowski, and C. Yeretzian, "Evidence of different flavour formation dynamics by roasting coffee from different origins: On-line analysis with PTR-ToF-{MS}", International Journal of Mass Spectrometry, Feb, 2014.
Link: http://www.sciencedirect.com/science/article/pii/S1387380614000657
Abstract
<p>Coffees from different origins were roasted to different roast degrees and along varying time temperature roasting profiles. The formation of volatile organic compounds (VOCs) during roasting was analyzed on-line by proton-transfer-reaction time-of-flight mass-spectrometry (PTR-ToF-MS). Coffee samples were Coffea arabica from Colombia, Guatemala (Antigua La Ceiba), Ethiopia (Yirga Cheffe, Djimmah) and Coffea canephora var. robusta from Indonesia (Malangsari). The roasting profiles ranged from high temperature short time (HTST) to low temperature long time (LTLT) roasting, and from medium to dark roast degree. The release dynamics of the on-line monitored VOCs differed for the different coffees and showed a strong modulation with the time&ndash;temperature roasting profile. While for Guatemalan coffee the formation of VOCs started relatively early in the roasting process, the VOC formation started much later in the case of Yirga Cheffe and Malangsari. Off-line analysis of the coffee brew augmented the measurements. These included headspace solid phase micro extraction gas chromatography mass spectrometry (HS SPME GC/MS), content of total solids, chlorogenic acids, caffeine, total polyphenols (Folin Ciocalteu), organic acids (ion chromatography), titratable acidity and pH. Some general trends, irrespective of the coffee origin, were observed, such as an increase in pH when going from an HTST to an LTLT profile or from a medium to dark roast degree. Furthermore, a decrease of total headspace intensity was observed from an HTST to an LTLT roasting profile. In general, the changes of the time temperature roasting profiles and/or the roast degree influenced the intensity of the respective coffee constituents as well as their relative composition differently for different coffee origins.</p>
[1607] Borduas, N., G. { da Silva}, J. G. Murphy, and J. P. D. Abbatt, "Experimental and Theoretical Understanding of the Gas Phase Oxidation of Atmospheric Amides with OH Radicals: Kinetics, Products, and Mechanisms.", J Phys Chem A, Jul, 2014.
Link: http://dx.doi.org/10.1021/jp503759f
Abstract
<p>Atmospheric amides have primary and secondary sources and are present in ambient air at low pptv levels. To better assess the fate of amides in the atmosphere, the room temperature (298 &plusmn; 3 K) rate coefficients of five different amides with OH radicals were determined in a 1 m(3) smog chamber using online proton-transfer-reaction mass spectrometry (PTR-MS). Formamide, the simplest amide, has a rate coefficient of (4.44 &plusmn; 0.46) &times; 10(-12) cm(3) molec(-1) s(-1) against OH, translating to an atmospheric lifetime of &sim;1 day. N-methylformamide, N-methylacetamide and propanamide, alkyl versions of formamide, have rate coefficients of (10.1 &plusmn; 0.6) &times; 10(-12), (5.42 &plusmn; 0.19) &times; 10(-12), and (1.78 &plusmn; 0.43) &times; 10(-12) cm(3) molec(-1) s(-1), respectively. Acetamide was also investigated, but due to its slow oxidation kinetics, we report a range of (0.4-1.1) &times; 10(-12) cm(3) molec(-1) s(-1) for its rate coefficient with OH radicals. Oxidation products were monitored and quantified and their time traces were fitted using a simple kinetic box model. To further probe the mechanism, ab initio calculations are used to identify the initial radical products of the amide reactions with OH. Our results indicate that N-H abstractions are negligible in all cases, in contrast to what is predicted by structure-activity relationships. Instead, the reactions proceed via C-H abstraction from alkyl groups and from formyl C(O)-H bonds when available. The latter process leads to radicals that can readily react with O2 to form isocyanates, explaining the detection of toxic compounds such as isocyanic acid (HNCO) and methyl isocyanate (CH3NCO). These contaminants of significant interest are primary oxidation products in the photochemical oxidation of formamide and N-methylformamide, respectively.</p>
2013
[Nyord2013] Nyord, T., D. Liu, J. Eriksen, and A. Peter S. Adamsen, "Effect of acidification and soil injection of animal slurry on ammonia and odour emission", , 2013.
Link: http://ramiran.net/doc13/Proceeding_2013/documents/S9.14..pdf
Abstract
Laboratory and field experiments examined ammonia (NH3) emissions after application of slurry on packed soil or fields. Acidified slurry reduced NH3 emissions significantly, and the greatest effect was obtained by lowering the pH from 7.8 to 6.8. The field trial demonstrated two acidification techniques to lower the slurry pH with good reduction of NH3 emission. NH3 emission was at the same level with soil injection of un-acidified slurry as acidified slurry applied by trailing hoses. In addition, we tested the development of some odorous compounds by covering the fields after application of un-treated or treated slurry with static chambers and measured the development of some odorous compound by proton-transfer-reaction mass spectrometry (PTR-MS).
[1697] del Pulgar}, J.. {Sánchez, A.. I. Carrapiso, R.. Reina, F.. Biasioli, and C.. García, "Effect of IGF-II genotype and pig rearing system on the final characteristics of dry-cured Iberian hams.", Meat Sci, vol. 95, pp. 586–592, Nov, 2013.
Link: http://dx.doi.org/10.1016/j.meatsci.2013.05.044
Abstract
<p>The effect of the IGF-II genotype (AG vs. GG) on the morphological and compositional parameters, the fatty acid composition of intramuscular fat, the odour concentration (analysed by dynamic olfactometry) and the volatile compound profile (analysed by proton transfer reaction time-of-flight mass spectrometry) of dry-cured Iberian ham was studied for the first time, and compared to the effect of pig rearing system (high-oleic concentrated feed vs. acorn and grass). The IGF-II genotype had no effect on most variables. However, it influenced the concentration of some odorants (methanethiol and octanal), although it did not affect odour concentration. Conversely, the rearing system had a significant effect on a large number of ham variables. Results indicate a negligible effect of the IGF-II genotype on the final ham quality and confirm that the rearing system has a marked effect.</p>
[SanchezdelPulgar2013] del Pulgar}, J.. {Sánchez, C.. Soukoulis, A.. I. Carrapiso, L.. Cappellin, P.. Granitto, E.. Aprea, A.. Romano, F.. Gasperi, and F.. Biasioli, "Effect of the pig rearing system on the final volatile profile of Iberian dry-cured ham as detected by PTR-ToF-MS.", Meat Sci, vol. 93, no. 3: IASMA Research and Innovation Centre, Fondazione Edmund Mach, Food Quality and Nutrition Department, Via E. Mach, 1, 38010S. Michele a/A, Italy., pp. 420–428, Mar, 2013.
Link: http://dx.doi.org/10.1016/j.meatsci.2012.10.003
Abstract
The volatile compound profile of dry-cured Iberian ham lean and subcutaneous fat from pigs fattened outdoors on acorn and pasture (Montanera) or on high-oleic concentrated feed (Campo) was investigated by proton transfer reaction time-of-flight mass spectrometry. In addition to the usual proton transfer ionization the novel switchable reagent ions system was implemented which allows the use of different precursor ions (H(3)O(+), NO(+) and O(2)(+)). The analysis of the lean and subcutaneous fat volatile compounds allowed a good sample discrimination according to the diet. Differences were evident for several classes of compounds: in particular, Montanera hams showed higher concentrations of aldehydes and ketones and lower concentrations of sulfur-containing compounds compared to Campo hams. The use of NO(+) as precursor ion confirmed the results obtained with H(3)O(+) in terms of classification capability and provides additional analytical insights.
[Manoukian2013] Manoukian, A.., E.. Quivet, B.. Temime-Roussel, M.. Nicolas, F.. Maupetit, and H.. Wortham, "Emission characteristics of air pollutants from incense and candle burning in indoor atmospheres.", Environ Sci Pollut Res Int, vol. -: Aix Marseille Université, CNRS, LCE, FRE 3416, 13331, Marseille Cedex 03, France., pp. -, Jan, 2013.
Link: http://dx.doi.org/10.1007/s11356-012-1394-y
Abstract
Volatile organic compounds (VOCs) and particles emitted by incense sticks and candles combustion in an experimental room have been monitored on-line and continuously with a high time resolution using a state-of-the-art high sensitivity-proton transfer reaction-mass spectrometer (HS-PTR-MS) and a condensation particle counter (CPC), respectively. The VOC concentration-time profiles, i.e., an increase up to a maximum concentration immediately after the burning period followed by a decrease which returns to the initial concentration levels, were strongly influenced by the ventilation and surface interactions. The obtained kinetic data set allows establishing a qualitative correlation between the elimination rate constants of VOCs and their physicochemical properties such as vapor pressure and molecular weight. The emission of particles increased dramatically during the combustion, up to 9.1(±0.2) x 10(4) and 22.0(±0.2) x 10(4) part cm(-3) for incenses and candles, respectively. The performed kinetic measurements highlight the temporal evolution of the exposure level and reveal the importance of ventilation and deposition to remove the particles in a few hours in indoor environments.
[1696] López-Aparicio, S.., and C.. Hak, "Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements.", Sci Total Environ, vol. 452-453, pp. 40–49, May, 2013.
Link: http://dx.doi.org/10.1016/j.scitotenv.2013.02.046
Abstract
<p>Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO2, O3, acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde&gt;150 ppm; acetic acid &asymp; 20-30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion.</p>
[Raseetha2013] Raseetha, S., I. Oey, DJ. Burritt, S. Heenan, and N. Hamid, "Evolution of antioxidant enzymes activity and volatile release during storage of processed broccoli ( Brassica oleracea L. italica)", LWT-Food Science and Technology: Elsevier, 2013.
Link: http://www.sciencedirect.com/science/article/pii/S0023643813001886
Abstract
The objective of this study was to investigate the effects of temperature treatments (i.e. freezing at −18 °C, cool storage at 4 °C and heating at 50, 70 and 100 °C for 10 min) on the activity of peroxidase (POD), lipoxygenase (LOX), ascorbic acid oxidase (AAO), superoxide dismutase (SOD) and catalase (CAT) in broccoli (Brassica oleracea L. italica). Volatiles released during storage at 20 °C for 24 h were monitored using on-line Proton Transfer Reaction Mass Spectrometry (m/z 21–180). Partial Least Square Regression (PLSR) was used to evaluate possible correlations between enzymes and volatiles released during storage. The results showed that temperature treatment had significant effect on all enzymes, except LOX. Temperature treatment at 70 °C resulted in at least 65% decrease in POD and AAO activity. In contrast, SOD and CAT activities generally increased during storage after temperature treatments. PLSR2 results showed that volatiles released after different temperature treatments and 24 h storage had a strong correlation with the residual activity of POD, AAO and SOD but not CAT and LOX. PLSR1 results suggested that POD had the highest correlation to volatile release during storage of processed broccoli followed by AAO, SOD, CAT and LOX (the least).
2012
[1512] Park, J.-H.., A.. H. Goldstein, J.. Timkovsky, S.. Fares, R.. Weber, J.. Karlik, and R.. Holzinger, "Eddy covariance emission and deposition flux measurements using proton transfer reaction-time of flight-mass spectrometry (PTR-TOF-{MS}): comparison with PTR-{MS} measured vertical gradients and fluxes", Atmospheric Chemistry and Physics Discussions, vol. 12, pp. 20435–20482, Aug, 2012.
Link: http://dx.doi.org/10.5194/acpd-12-20435-2012
Abstract
<p>During summer 2010, a proton transfer reaction-time of flight-mass spectrometer (PTR-TOF-MS) and a standard proton transfer reaction mass spectrometer (PTR-MS) were deployed simultaneously for one month in an orange orchard in the Central Valley of California to collect continuous data suitable for eddy covariance (EC) flux calculations. The high time resolution (5 Hz) and high mass resolution (up to 5000 m Δ m&minus;1) data from the PTR-TOF-MS provided the basis for calculating the concentration and flux for a wide range of volatile organic compounds (VOC). Throughout the campaign, 664 mass peaks were detected in mass-to-charge ratios between 10 and 1278. Here we present PTR-TOF-MS EC fluxes of the 27 ion species for which the vertical gradient was simultaneously measured by PTR-MS. These EC flux data were validated through spectral analysis (i.e. co-spectrum, normalized co-spectrum, and ogive). Based on inter-comparison of the two PTR instruments, no significant instrumental biases were found in either mixing ratios or fluxes, and the data showed agreement within 5% on average for methanol and acetone. For the measured biogenic volatile organic compounds (BVOC), the EC fluxes from PTR-TOF-MS were in agreement with the qualitatively inferred flux directions from vertical gradient measurements by PTR-MS. For the 27 selected ion species reported here, the PTR-TOF-MS measured total (24 h) mean net flux of 299 μg C m&minus;2 h&minus;1. The dominant BVOC emissions from this site were monoterpenes (m/z 81.070 + m/z 137.131 + m/z 95.086, 34%, 102 μg C m&minus;2 h&minus;1) and methanol (m/z 33.032, 18%, 72 μg C m&minus;2 h&minus;1). The next largest fluxes were detected at the following masses (attribution in parenthesis): m/z 59.048 (mostly acetone, 12.2%, 36.5 μg C m&minus;2 h&minus;1), m/z 61.027 (mostly acetic acid, 11.9%, 35.7 μg C m&minus;2 h&minus;1), m/z 93.069 (para-cymene + toluene, 4.1%, 12.2 μg C m&minus;2 h&minus;1), m/z 45.033 (acetaldehyde, 3.8%, 11.5 μg C m&minus;2 h&minus;1), m/z 71.048 (methylvinylketone + methacrolein, 2.4%, 7.1 μg C m&minus;2 h&minus;1), and m/z 69.071 (isoprene + 2-methyl-3-butene-2-ol, 1.8%, 5.3 μg C m&minus;2 h&minus;1). Low levels of emission and/or deposition (&lt;1.6% for each, 5.8% in total flux) were observed for the additional reported masses. Overall, our results show that EC flux measurements using PTR-TOF-MS is a powerful new tool for characterizing the biosphere-atmosphere exchange including both emission and deposition for a large range of BVOC and their oxidation products.</p>
[Hansen2012c] Hansen, M. J., A. P. S. Adamsen, K. E. N. Jonassen, and A. Feilberg, "The effect of pit ventilation on the emission of odorants from pig production", CHEMICAL ENGINEERING, vol. 30, 2012.
Link: http://www.aidic.it/cet/12/30/039.pdf
[Hansen2012] Hansen, M. J. Ã. ¸rgen, K. Toda, T. Obata, A. Peter S. Adamsen, and A. Feilberg, "Evaluation of single column trapping/separation and chemiluminescence detection for measurement of methanethiol and dimethyl sulfide from pig production.", J Anal Methods Chem, vol. 2012: Department of Engineering, Science and Technology, Aarhus University, Blichers Allé 20, 8830 Tjele, Denmark., pp. 489239, 2012.
Link: http://dx.doi.org/10.1155/2012/489239
Abstract
Reduced sulfur compounds are considered to be important odorants from pig production due to their low odor threshold values and low solubility in slurry. The objective of the present study was to investigate the use of a portable method with a single silica gel column for trapping/separation coupled with chemiluminescence detection (SCTS-CL) for measurement of methanethiol and dimethyl sulfide in sample air from pig production. Proton-transfer-reaction mass spectrometry (PTR-MS) was used to evaluate the trapping/separation. The silica gel column used for the SCTS-CL efficiently collected hydrogen sulfide, methanethiol and dimethyl sulfide. The measurement of methanethiol by SCTS-CL was clearly interfered by the high concentration of hydrogen sulfide found in pig production, and a removal of hydrogen sulfide was necessary to obtain reliable results. Air samples taken from a facility with growing-finishing pigs were analyzed by SCTS-CL, PTR-MS, and a gas chromatograph with sulfur chemiluminescence detection (GC-SCD) to evaluate the SCTS-CL. The difference between the concentrations of methanethiol and dimethyl sulfide measured with SCTS-CL, PTR-MS, and GC-SCD was below 10%. In conclusion, the SCTS-CL is a portable and low-cost alternative to the commercial methods that can be used to measure methanethiol and dimethyl sulfide in sample air from pig production.
[Aaltonen2012] Aaltonen, H., and , "Exchange of volatile organic compounds in the boreal forest floor", : Helsingin yliopisto, 2012.
Link: https://helda.helsinki.fi/handle/10138/37593
Abstract
Terrestrial ecosystems, mainly plants, emit large amounts of volatile organic compounds (VOCs) into the atmosphere. In addition to plants, VOCs also have less-known sources, such as soil. VOCs are a very diverse group of reactive compounds, including terpenoids, alcohols, aldehydes and ketones. Due to their high reactivity, VOCs take part in chemical reactions in the atmosphere and thus also affect Earth s radiation balance. In this study, chamber and snow gradient techniques for measuring boreal soil and forest floor VOC fluxes were developed. Spatial and temporal variability in fluxes was studied with year-round measurements in the field and the sources of boreal soil VOCs in the laboratory with fungal isolates. Determination of the compounds was performed mass spectrometrically. This study reveals that VOCs from soil are emitted by living roots, above- and belowground litter and microbes. The strongest source appears to be litter, in which both plant residuals and decomposers play a role in the emissions. Temperature and moisture are the most critical physical factors driving VOC fluxes. Since the environment in boreal forests undergoes strong seasonal changes, the VOC flux strength of the forest floor varies markedly during the year, being highest in spring and autumn. The high spatial heterogeneity of the forest floor was also clearly visible in VOC fluxes. The fluxes of trace gases (CO2, CH4 and N2O) from soil, which are also related to the soil biological activity and physical conditions, did not correlate with the VOC fluxes. Our results show that emissions of VOCs from the boreal forest floor accounts for as much as several tens of percent, depending on the season, of the total forest ecosystem VOC emissions. This can be utilized in air chemistry models, which are almost entirely lacking the below-canopy compartment.
2011
[Ruuskanen2011] Ruuskanen, TM., M. Müller, R. Schnitzhofer, T. Karl, M. Graus, I. Bamberger, L. Hoertnagl, F. Brilli, G. Wohlfahrt, and A. Hansel, "Eddy covariance VOC emission and deposition fluxes above grassland using PTR-TOF", Atmos. Chem. Phys, vol. 11, pp. 611–625, 2011.
Link: http://www.atmos-chem-phys.net/11/611/2011/acp-11-611-2011.html
Abstract
Eddy covariance (EC) is the preferable technique for flux measurements since it is the only direct flux determination method. It requires a continuum of high time resolution measurements (e.g. 5–20 Hz). For volatile organic compounds (VOC) soft ionization via proton transfer reaction has proven to be a quantitative method for real time mass spectrometry; here we use a proton transfer reaction time of flight mass spectrometer (PTR-TOF) for 10 Hz EC measurements of full mass spectra up to m/z 315. The mass resolution of the PTR-TOF enabled the identification of chemical formulas and separation of oxygenated and hydrocarbon species exhibiting the same nominal mass. We determined 481 ion mass peaks from ambient air concentration above a managed, temperate mountain grassland in Neustift, Stubai Valley, Austria. During harvesting we found significant fluxes of 18 compounds distributed over 43 ions, including protonated parent compounds, as well as their isotopes and fragments and VOC-H+ – water clusters. The dominant BVOC fluxes were methanol, acetaldehyde, ethanol, hexenal and other C6 leaf wound compounds, acetone, acetic acid, monoterpenes and sequiterpenes.
[1489] Gordon, S.. M., M.. C. Brinkman, R.. Q. Meng, G.. M. Anderson, J.. C. Chuang, R.. R. Kroeger, I.. L. Reyes, and P.. I. Clark, "Effect of Cigarette Menthol Content on Mainstream Smoke Emissions", Chemical Research in Toxicology, vol. 24, pp. 1744-1753, 2011.
Link: http://pubs.acs.org/doi/abs/10.1021/tx200285s
Abstract
<p>The 2009 Family Smoking Prevention and Tobacco Control Act empowered the U.S. Food and Drug Administration to study &ldquo;the impact of the use of menthol in cigarettes on the public health, including such use among children, African Americans, Hispanics and other racial and ethnic minorities,&rdquo; and develop recommendations. Current scientific evidence comparing human exposures between menthol and nonmenthol smokers shows mixed results. This is largely because of the many differences between commercial menthol and nonmenthol cigarettes other than their menthol content. We conducted an innovative study using two types of test cigarettes: a commercial nonmenthol brand that we mentholated at four different levels, and Camel Crush, a commercial cigarette containing a small capsule in the filter that releases menthol solution into the filter when crushed. Cigarettes were machine-smoked at each of the menthol levels investigated, and the total particulate matter (TPM) was collected on a quartz fiber filter pad and analyzed by gas chromatography/mass spectrometry for menthol, nicotine, tobacco-specific nitrosamines (TSNAs), polycyclic aromatic hydrocarbons (PAHs), cotinine, and quinoline. The mainstream smoke was also monitored continuously in real time on a puff-by-puff basis for seven gas-phase constituents (acetaldehyde, acetonitrile, acrylonitrile, benzene, 1,3-butadiene, isoprene, and 2,5-dimethylfuran), using a proton transfer reaction-mass spectrometer. Average yields (in micrograms/cigarette) for the analytes were determined. Menthol in the TPM samples increased linearly with applied menthol concentration, but the amounts of nicotine along with the target TSNAs, PAHs, cotinine, and quinoline in the cigarettes remained essentially unchanged. Similarly, yields of the targeted volatile organic compounds (VOCs) in whole smoke from the mentholated nonmenthol cigarettes that were measured in real-time were largely unaffected by their menthol levels. In the Camel Crush cigarettes, however, the VOC yields appeared to increase in the presence of menthol, especially in the gas phase. Although we succeeded in characterizing key mainstream smoke constituents in cigarettes that differ only in menthol content, further study is needed to definitively answer whether menthol affects exposure to selected cigarette constituents and thereby influences harm.</p>
[Liu2011] Liu, D., A. Feilberg, A. P. S. Adamsen, and K. E. N. Jonassen, "The effect of slurry treatment including ozonation on odorant reduction measured by in-situ PTR-MS", Atmospheric Environment, vol. 45, no. 23: Elsevier, pp. 3786–3793, 2011.
Link: http://www.sciencedirect.com/science/article/pii/S1352231011004067
Abstract
The emission of odorous compounds from intensive pig production facilities is a nuisance for neighbors. Slurry ozonation for odor abatement has previously been demonstrated in laboratory scale. In this study, the effect of slurry ozonation (combined with solid–liquid pre-separation and acidification) on emissions of odorous compounds was tested in an experimental full-scale growing pig facility using Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) for online analysis of odorants. The measurements were performed to gain a better understanding of the effects of ozone treatment on emissions odorous compounds and to identify potential options for optimization of ozone treatment. The compounds monitored included volatile sulfur compounds, amine, carboxylic acids, ketones, phenols and indoles. Measurements were performed during nearly a one-month period in summertime. The compounds with the highest concentrations observed in the ventilation exhaust duct were acetic acid, hydrogen sulfide, propanoic acid and butanoic acid. The compounds with the highest removal efficiencies were hydrogen sulfide, 3-methyl-indole, phenol and acetic acid. Based on odor threshold values, methanethiol, butanoic acid, 4-methylphenol, hydrogen sulfide and C5 carboxylic acids are estimated to contribute significantly to the odor nuisance. Emissions of odorous compounds were observed to be strongly correlated with temperature with the exception of hydrogen sulfide. Emission peaks of sulfur compounds were seen during slurry handling activities. Discharging of the slurry pit led to reduced hydrogen sulfide emissions, but emissions of most other odorants were not affected. The results indicate that emissions of odorants other than hydrogen sulfide mainly originate from sources other than the treated slurry, which limits the potential for further optimization. The PTR-MS measurements are demonstrated to provide a quantitative, accurate and detailed evaluation of ozone treatment for emission reduction.

Pages

Featured Articles

Download Contributions to the International Conference on Proton Transfer Reaction Mass Spectrometry and Its Applications:

 

Selected PTR-MS related Reviews

F. Biasioli, C. Yeretzian, F. Gasperi, T. D. Märk: PTR-MS monitoring of VOCs and BVOCs in food science and technology, Trends in Analytical Chemistry 30 (7) (2011).
Link

J. de Gouw, C. Warneke, T. Karl, G. Eerdekens, C. van der Veen, R. Fall: Measurement of Volatile Organic Compounds in the Earth's Atmosphere using Proton-Transfer-Reaction Mass Spectrometry. Mass Spectrometry Reviews, 26 (2007), 223-257.
Link

W. Lindinger, A. Hansel, A. Jordan: Proton-transfer-reaction mass spectrometry (PTR–MS): on-line monitoring of volatile organic compounds at pptv levels, Chem. Soc. Rev. 27 (1998), 347-375.
Link

 

Lists with PTR-MS relevant publications of the University of Innsbruck can be found here: Atmospheric and indoor air chemistry, IMR, Environmental Physics and Nano-Bio-Physics

 

Download the latest version of the IONICON publication database as BibTeX.