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Size Resolved Mass and Elemental Composition of Ground Collected Aerosols over South-East Italy
No full textRelation of air mass source regions to PM10 mass concentrations using back trajectories
No full textAbstract T06A195
Ionic and elemental composition of TSP, PM10, and PM2.5 samples collected over South-East Italy
No full text24-hour TSP, PM10, and PM2.5 samples collected from June to October 2004 at a suburban site of south-east Italy, in the Central Mediterranean, have been analyzed to investigate the dependence of mass concentrations and of ionic (F-, Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, Ca2+) and elemental (Ti, Al, Si, Fe, Mn, Cu, Zn, Pb, Cd) components on particulate matter (PM) fraction
Composition of Fine and Coarse Particles in a coastal site of the Central Mediterranean: carbonaceous specie contributions
No full textTotal Suspended Particulate (TSP) and PM2.5 samples simultaneously collected at a coastal site (40.4°N; 18.1°E) in the central Mediterranean are analyzed to investigate the relative role of ions (Cl-, NO3-, SO42-, Na+, NH4+, K+, Mg2+, Ca2+) and carbonaceous species in the fine (PM2.5) and coarse (TSP-PM2.5) sampled mass and contribute to the characterization of the Central Mediterranean particulate. A methodology is described to determine carbonate carbon (CC), organic carbon (OC), and elemental carbon (EC) levels from Thermal Optical Transmittance (TOT) measurements since carbonate particles may significantly contribute to the Mediterranean particulate. We have found that CC levels vary up to 1.7 g/m3 and 0.8 g/m3 in the coarse and fine fraction, respectively. OC and EC levels vary up to 3.0 g/m3 and 1.5 g/m3, respectively in the coarse fraction, and vary within the 2.2-10 g/m3 and 0.5-5 g/m3 range, respectively in the fine fraction. Hence, it is shown that OC levels may be quite overestimated mainly in the coarse fraction, if the CC contribution is not accounted for. CO32- levels (calculated from CC concentrations) account on average for 6% and 10% of the fine (PM2.5) and coarse (TSP-PM2.5) sampled mass, respectively and allow balancing the anion deficit resulting from the ionic balance of ions detected by ion-chromatography (IC). Total carbon TC = (OC+EC) accounts on average for 29% and 6% of the fine and coarse mass, respectively. IC ions account for 38% and 17% of the fine and coarse mass, respectively. OC, EC, SO42-, NH4+, and K+ are the major components in the fine fraction, accounting on average for 84% of the analyzed PM2.5mass. Marine- and crust-originated ions (Cl-, Mg2+, Na+, Ca2+, CO32-) and NO3- are mainly in the coarse fraction and represent on average 83% of the analyzed coarse mass. A discussion on the main reactions leading to the loss of ammonium particulate in the coarse fraction is provided. It is also shown that the Cl-/Na+ ratio varies within the 0.1-0.8 and 0.0-1.0 range in the fine and coarse particle fraction, respectively for the occurrence of Cl depletion processes
Advection patterns and composition of TSP and PM2.5 samples over south-east Italy
No full text24-hour Total Suspended Particulate (TSP) matter and PM2.5 samples have simultaneously been collected at a subrban site of South-East Italy to investigate the dependence of TSP and PM2.5 mass concentrations on long-range transported air masses
In Situ Samplings and Remote Sensing Measurements to Characterize Aerosol Properties over Southeast Italy
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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