lnstitut für Sensorik und Elektronik
Dauerhafte URI für die Sammlunghttps://irf.fhnw.ch/handle/11654/28068
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Ergebnisse nach Hochschule und Institut
Publikation Secondary organic aerosol formation by irradiation of 1,3,5-trimethylbenzene−NOₓ-H2O in a new reaction chamber for atmospheric chemistry and physics(American Chemical Society, 12.03.2005) Paulsen, Dwane; Dommen, Josef; Kalberer, Markus; Prévôt, André S.H.; Richter, René; Sax, Mirjam; Steinbacher, Martin; Weingartner, Ernest; Baltensperger, UrsA new environmental reaction smog chamber was built to simulate particle formation and growth similar to that expected in the atmosphere. The organic material is formed from nucleation of photooxidized organic compounds. The chamber is a 27 m³ fluorinated ethylene propylene (FEP) bag suspended in a temperature-controlled enclosure. Four xenon arc lamps (16 kW total) are used to irradiate primary gas components for experiments lasting up to 24 h. Experiments using irradiations of 1,3,5-trimethylbenzene−NOₓ−H2O at similar input concentrations without seed particles were used to determine particle number and volume concentration wall loss rates of 0.209 ± 0.018 and 0.139 ± 0.070 1/h, respectively. The particle formation was compared with and without propene.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Using aerosol light absorption measurements for the quantitative determination of wood burning and traffic emission contributions to particulate matter(American Chemical Society, 02.04.2008) Sandradewi, Jisca; Prévôt, André S. H.; Szidat, Sönke; Perron, Nolwenn; Alfarra, M. Rami; Lanz, Valentin A.; Weingartner, Ernest; Baltensperger, UrsA source apportionment study was performed for particulate matter in the small village of Roveredo, Switzerland, where more than 70% of the households use wood burning for heating purposes. A two-lane trans-Alpine highway passes through the village and contributes to the total aerosol burden in the area. The village is located in a steep Alpine valley characterized by strong and persistent temperature inversions during winter, especially from December to February. During two winter and one early spring campaigns, a seven-wavelength aethalometer, high volume (HIVOL) samplers, an Aerodyne quadrupole aerosol mass spectrometer (AMS), an optical particle counter (OPC), and a Sunset Laboratory OCEC analyzer were deployed to study the contribution of wood burning and traffic aerosols to particulate matter. A linear regression model of the carbonaceous particulate mass in the submicrometer size range CM(PM1) as a function of aerosol light absorption properties measured by the aethalometer is introduced to estimate the particulate mass from wood burning and traffic (PMwb, PMtraffic). This model was calibrated with analyses from the 14C method using HIVOL filter measurements. These results indicate that light absorption exponents of 1.1 for traffic and 1.8–1.9 for wood burning calculated from the light absorption at 470 and 950 nanometers should be used to obtain agreement of the two methods regarding the relative wood burning and traffic emission contributions to CM(PM1) and also to black carbon. The resulting PMwb and PMtraffic values explain 86% of the variance of the CM(PM1) and contribute, on average, 88 and 12% to CM(PM1), respectively. The black carbon is estimated to be 51% due to wood burning and 49% due to traffic emissions. The average organic carbon/total carbon (OC/TC) values were estimated to be 0.52 for traffic and 0.88 for wood burning particulate emissions.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Hygroscopic properties of fresh and aged wood burning particles(Elsevier, 2013) Martin, Maria; Tritscher, Torsten; Jurányi, Zsófia; Heringa, Maarten F.; Sierau, Berko; Weingartner, Ernest; Chirico, Roberto; Gysel, Martin; Prévôt, André S.H.; Baltensperger, Urs; Lohmann, Ulrike01A - Beitrag in wissenschaftlicher Zeitschrift