Assessment of the impact of ship emissions on the air quality in Naples

The paper reports the results of a monitoring campaign of SO2, NO2 and Benzene carried out in the port of Naples and inside the nearby urban canopy from 20th January to 8th March 2016. The activity is a continuation of a previous monitoring campaign realized by the authors in 2012. About 40 passive samplers were placed and average concentration in the period for the three pollutants was evaluated. Concentration levels observed are lower than limit values established by European directives both for SO2 and NO2. Benzene in some place of measure exceeded the limit value (5 ìg/m3) that is fixed, however, as annual average. Results have been interpreted by an interpolation algorithm using the software SURFER® obtaining contour maps that show significant differences among the three pollutants. In fact, maximum levels of SO2 occur inside the harbour area, those of NO2 inside the urban area while Benzene maximum average concentrations in the period occur at the boundary between port and urban canopy. This result has been interpreted on the basis of the occurrences of wind direction and speed measured in the same observation period

Monitoring the quality of air in the port of Naples

This paper presents the main results of a campaign of full scale tests on the quality of the air in the port of Naples together with an analysis of the spatial distribution of pollutants, and of the correlation between their concentrations in air with ship activities in por

Leaves of Quercus ilex L. as biomonitors of PAHs in the air of Naples (Italy).

Polycyclic aromatic hydrocarbons (PAHs) were determined by the GC-MS chromatography in the leaves of Quercus ilex L., an evergreen Mediterranean oak, to monitor the degree of pollution in the urban area of Naples compared to remote areas. Leaf samples were collected in July 1998 from four urban parks, six roadsides and two sites in remote areas. The total PAH contents in Q. ilex leaves ranged from 106.6 in a control site to 4607.5 ng/g d.w. along a road with a high traffic flow. The mean concentration factors (urban/control) were 3.8 for the parks and 15 for the roads. The contribution of carcinogenic PAHs (benz[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, indeno[1,2,3-c,d]pyrene)was higher in urban area and di!ered according to the site, ranging from 6.7% to 21.3%. The total PAH burden in control sites was dominated by the low molecular weight PAHs, whilst along the urban roads fluoranthene, pyrene and benz[a]anthracene among the measured PAHs showed the highest values. PAHs were positively correlated (P<0.01) to trace metals measured in a previous study

Study of the azo-hydrazone tautomerism of Acid Orange 20 by spectroscopic techniques: UV\u2013Visible, Raman, and surface-enhanced Raman scattering

Acid Organge 20 is a synthetic monoazo dye, which molecular structure consists of a naphtol unit and a sulfonated benezene ring linked together by an azo chromophore group. As a phenylazonaphthol with the OH group in para position respect to the azo group, it undergoes an azo-hydrazone tautomerism. In this work, the study of the preponderance of one tautomer over the other in different pH conditions was carried out by means of UV\u2013Vis, Raman, and surface-enhanced Raman scattering (SERS) spectroscopies. Raman spectra of powder and aqueous solutions of the dye were obtained at different excitation lines at the natural pH of the AO20 solutions. The best results were obtained at 633 nm, and the observed Raman bands suggested the presence of the hydrazone tautomer. The molecular structure and the theoretical Raman spectra of the two tautomers were calculated by density functional theory (DFT) methods. The obtained results were used for the assignment of the Acid Orange 20 vibrational modes. The SERS analysis of the dye solutions were carried out employing Ag nanostars, pH below and above 4.7, and excitation at 442, 532, and 633 nm. The hydrazone tautomer was prevalent in most conditions. The azo tautomer was only detected at pH ~ 5 under excitation with the 532 nm wavelength due to resonant Raman conditions. Finally, the effect of pH on the morphology of metal nanoparticles employed as SERS substrates was evaluated by TEM

Leaf accumulation of trace elements and polycyclic aromatic hydrocarbons (PAHs) in Quercus ilex L

Quercus ilex L. leaves were collected four times in one year at six urban sites and one remote area in order to determine trace element and PAH accumulation through concomitant analyses of unwashed and water-washed leaves. Both unwashed and washed leaves showed the highest amounts of trace elements and PAHs in the urban area. Unwashed leaves showed greater differences between urban and remote areas and among the urban sites than washed leaves for trace element and PAH concentrations. Water-washing resulted in a significant (P < 0.001) decrease in leaf concentrations of Cr, Cu, Fe, Pb, V and Zn. By contrast, Cd and total PAH concentrations showed no differences between unwashed and washed leaves