Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
A closure study of sub-micrometer aerosol particle hygroscopic behaviour
Autore:
Swietlicki, E; Zhou, JC; Berg, OH; Martinsson, BG; Frank, G; Cederfelt, SI; Dusek, U; Berner, A; Birmili, W; Wiedensohler, A; Yuskiewicz, B; Bower, KN;
Indirizzi:
Univ Lund, Div Nucl Phys, S-22100 Lund, Sweden Univ Lund Lund Sweden S-22100 Lund, Div Nucl Phys, S-22100 Lund, Sweden Univ Vienna, Inst Expt Phys, A-1090 Vienna, Austria Univ Vienna Vienna Austria A-1090 Inst Expt Phys, A-1090 Vienna, Austria Inst Troposher Res, D-04318 Leipzig, Germany Inst Troposher Res Leipzig Germany D-04318 Res, D-04318 Leipzig, Germany UMIST, Dept Phys, Manchester M60 1QD, Lancs, England UMIST Manchester Lancs England M60 1QD Manchester M60 1QD, Lancs, England
Titolo Testata:
ATMOSPHERIC RESEARCH
fascicolo: 3-4, volume: 50, anno: 1999,
pagine: 205 - 240
SICI:
0169-8095(199903)50:3-4<205:ACSOSA>2.0.ZU;2-3
Fonte:
ISI
Lingua:
ENG
Soggetto:
AQUEOUS-PHASE-TRANSITIONS; CLOUD EXPERIMENT 1993; ATMOSPHERIC AEROSOL; RELATIVE-HUMIDITY; WATER ACTIVITIES; ORGANIC FILMS; GRAND-CANYON; LOS-ANGELES; SIZE; MODEL;
Keywords:
aerosol particles; hygroscopic growth; tandem differential mobility analyser (TDMA); closure study;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
67
Recensione:
Indirizzi per estratti:
Indirizzo: Swietlicki, E Univ Lund, Div Nucl Phys, POB 118, S-22100 Lund, Sweden UnivLund POB 118 Lund Sweden S-22100 S-22100 Lund, Sweden
Citazione:
E. Swietlicki et al., "A closure study of sub-micrometer aerosol particle hygroscopic behaviour", ATMOS RES, 50(3-4), 1999, pp. 205-240

Abstract

The hygroscopic properties of sub-micrometer aerosol particles were studied in connection with a ground-based cloud experiment at Great Dun Fell, in northern England in 1995. Hygroscopic diameter growth factors were measuredwith a Tandem Differential Mobility Analyser (TDMA) for dry particle diameters between 35 and 265 nm at one of the sites upwind of the orographic cloud. An external mixture consisting of three groups of particles, each with different hygroscopic properties, was observed. These particle groups were denoted less-hygroscopic, more-hygroscopic and sea spray particles and had average diameter growth factors of 1.11-1.15, 1.38-1.69 and 2.08-2.21 respectively when taken from a dry state to a relative humidity of 90%. Average growth factors increased with dry particle size. A bimodal hygroscopic behaviour was observed for 74-87% of the cases depending on particle size. Parallel measurements of dry sub-micrometer particle number size distributions were performed with a Differential Mobility Particle Sizer (DMPS). The inorganic ion aerosol composition was determined by means of ion chromatographyanalysis of samples collected with Berner-type low pressure cascade impactors at ambient conditions. The number of ions collected on each impactor stage was predicted from the size distribution and hygroscopic growth data bymeans of a model of hygroscopic behaviour assuming that only the inorganicsubstances interacted with the ambient water vapour. The predicted ion number concentration was compared with the actual number of all positive and negative ions collected on the various impactor stages. For the impactor stage which collected particles with aerodynamic diameters between 0.17-0.53 mu m at ambient relative humidity, and for which all pertinent data was available for the hygroscopic closure study, the predicted ion concentrations agreed with the measured values within the combined measurement and model uncertainties for all cases but one. For this impactor sampling occasion, thepredicted ion concentration was significantly higher than the measured. The air mass in which this sample was taken had undergone extensive photochemical activity which had probably produced hygroscopically active material other than inorganic ions, such as organic oxygenated substances. (C) 1999 Elsevier Science B.V. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 23/09/20 alle ore 16:00:48