Diurnal variation of aethalometer correction factors and optical absorption assessment of nucleation events using multi-wavelength photoacoustic spectroscopy

作     者：Tibor Ajtai Gergely Kiss-Albert Noemi Utry Adam Toth Andras Hoffer Gabor Szabo Zoltan Bozoki 

作者机构：Department of Optics and Quantum Electronics University of Szeged H-6720 Szeged Hungary Hilase Development Production Service and Trading Limited Szekesfehervar H-8000 Hungary MTA-SZTE Research Group on Photoacoustic Spectroscopy H-6720 Szeged Hungary ELI-HU Non-Profit Ltd H-6720 Szeged Hungary Department of Earth and Environmental Sciences University of Pannonia P.O. Box 158 Veszprem H-8201 Hungary MTA-PE Air Chemistry Research Group P.O. Box 158 Veszprem H-8201 Hungary 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2019年第31卷第9期

页      面：96-109页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

基　　金：supported by the project GINOP-2.3.2-15-2016-00036 supported by the European Union,co-financed by the European Social Fund under project number EFOP-3.6.1-16-2016-00014 

主　　题：Photoacoustic spectroscopy Aerosol Angstr?m exponent Aethalometer Nucleation Size distribution 

摘      要：A field measurement campaign was carried out during the late winter and early spring of2015 in Budapest, the capital of Hungary. The size distribution(SD) and optical absorption of carbonaceous particulate matter(CPM) was measured online using a Scanning Mobility Particle Sizer(SMPS), a 7λ-aethalometer and an inhouse developed 4λ-Photoacoustic Spectrometer. Based on the SD data, the measurement period could be classified into days with and without new particle formation events(normal days and nucleation days),although particular nucleation-like events were observed on normal days as well. Three characteristic size modes were observed with CMDs of circa 15, 25 and 110 nm that corresponded to the nucleation, traffic and heating modes. Based on the temporal behavior of these modes both types of days were divided into distinctive daily periods(heating hours,traffic hours and nucleation hours). The optical absorption spectra(OAC and AAE) also displayed the same part of day behavior to that of SD. That way this paper is among the first to assess the optical response of urban nucleation events. Due to the simultaneous measurement of OAC by the 7λ-aethalometer and a 4λ-Photoacoustic Spectrometer, OAC was measured overall at 11 wavelengths. That way aethalometer correction factors(f and C)were determined at all aethalometer wavelengths using in situ reference photoacoustic measurements. Correction factors were found to have both wavelength and time of the day variation. In the case of f, no clear trend could be observed, however, Cref values increased both as a function of wavelength.