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Abstract  

Size-fractionated aerosol samples collected with micro-orifice impactors at Camden, NJ, a heavily industrialized urban area, and at two sites near Washington, DC, were analyzed for elemental constituents determined instrumentally from short-lived neutron activation products. A least-squares peak-fitting method was used with impactor calibration data to determine log-normal distribution parameters, i.e., mass median aerodynamic diameter (MMAD) and geometric standard deviation ( g) for particles bearing S, V, Br, and I. For these elements, MMADs ranged from 0.24 to 0.65 m; 0.23 to 0.53 m; 0.22 to 0.61 m, and 0.20 to 0.48 m, respectively.

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Abstract  

Concentrations of elements in fine and coarse PM10 samples collected in Ho Chi Minh City were determined by INAA for the purpose of characterising air pollution sources using multivariate receptor modeling techniques. Seven sources common to coarse and fine samples were identified. Resuspended soil dust is dominant in the coarse samples accounting for 41% of the particulate mass. In the fine samples, vehicle emissions and coal burning are most important accounting for about 20% each. Although a great number of elements were included in the input data for receptor modeling, the interpretation of emission sources was not always straightforward. Information on other source markers were needed. Therefore, a polarography method was used for quantifying lead, and recently, ion chromatography method became available for quantifying secondary sulphates, nitrates and other water soluble ions.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Almeida, M. Freitas, C. Repolho, I. Dionísio, H. Dung, A. Caseiro, C. Alves, C. Pio, and A. Pacheco

Abstract  

The goal of this research is to determine trends and sources of airborne particulates in the centre of Lisbon, by using speciated particulate-matter data and back-trajectory analyses. Results showed that, in 2007, the annual PM2.5 concentration exceeded the World Health Organization recommended levels. PM2.5 diurnal variability and the ratio between weekdays’ and weekends’ concentrations indicated that traffic contributed highly to decreasing air quality. Air back-trajectory analysis showed that maritime air mass transport had a significant role on air quality in Lisbon, promoting the decrease of anthropogenic aerosol concentrations.

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Abstract  

The application of Mössbauer spectroscopy, X-ray diffractometry, thermogravimetric analysis and PIXE in the characterization of the particulate matter in atmospheric aerosols in Metropolitan Region of Vitória (MRV), Brazil have been investigated. The main sources of particulate matter, natural, industrial and antropogenic from human activities, have been studied to identify its contribution in the atmospheric particles. During the years 1995 to 1999 samples of total suspended particles (TSP, Ø 100 m) were collected from four points within MRV. The inhalable particles (PM10 Ø 10 m) and sedimented particles (SP) were also collected from the same region. A receptor modeling was used for the identification of the source of particulate matter in the collected urban aerosol.

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Abstract  

The significant differences in the activities of 210Pb, 210Bi, 210Po and cosmogenic 7Be and 22Na radionuclides in the urban aerosol samples collected in the summers 2010 and 2011 in the Lodz city of Poland were observed. Simultaneous measurement of these radionuclides, after a simple modification of the one compartment model, allows us to calculate both: the corrected aerosol residence times in the troposphere (1 ÷ 25 days) and in the lower stratosphere (103 ÷ 205 days). The relative input of the additional sources (beside of the 222Rn decay in the air) to the total activity concentrations of 210Pb, 210Bi and 210Po radionuclides in the urban air, plays a substantial role (up to 97% of the total activity) only in the case of 210Po.

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concentrations of urban aerosol particles . Atmos. Environ. 40 . 1427 - 1440 . Informative Inventory ReporT 2015 – Hungary . , 2017 . Hungarian Meteorological Service pp. 176 . http

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Investigation of polymers by a novel analytical approach for evolved gas analysis in thermogravimetry

Gas chromatography comprehensively coupled to single photon ionization mass spectrometry

Journal of Thermal Analysis and Calorimetry
Authors: Mohammad R. Saraji-Bozorgzad, Thorsten Streibel, Markus Eschner, Thomas M. Groeger, Robert Geissler, Erwin Kaisersberger, Thomas Denner, and Ralf Zimmermann

. Streibel T , Mitschke S , Welthagen W , Adam T , Zimmermann R . Thermal desorption coupled with resonance enhanced multiphoton ionization time-of-flight mass spectrometry (REMPI–TOFMS) for the analysis of PAH content of urban

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