13 research outputs found
Atmospheric particulate element concentrations and deposition rates in French Polynesia
Over a period of eight months, a total of 26 atmospheric particulate matter samples were collected at the location of Tahiti and in other areas of French Polynesia, using a specially equipped sailboat. A 6-stage cascade impact or was used to separate aerosols in the following size classes: > 4,2-4, 1-2,0.5-1,0.25-0.5 and -1, while the scavenging rates were of the order of 2-3 x10-6 S-1. The resulting deposition rates are within the range given in the literature, with a good agreement for the deposition of Mn, Cu and Zn. It was found that dry deposition dominates over wet deposition for the sea derived elements, while for the crustal elements, the situation was the opposite. The estimated annual atmospheric deposition of Cu is equal to that of other geochemical cycles such as marine sedimentation and vertical mixing, whereas the deposition rates of mineral aerosol and Pb are much higher than those reported previously, indicating direct influence of local emissions from Tahiti
Chemical characterization of airborne particles in St. Martinus Cathedral in Weert, The Netherlands
Electron probe X-ray microanalysis (EPMA) of single particles and energy dispersive X-ray fluorescence analysis (EDXRF) were applied to determine the chemical composition, size and probable origin of the suspended particulate matter. The aim of the performed research was to determine the chemical composition, size and abundance of aerosol particles responsible for blackening and soiling of the works of art displayed within the Cathedral of Weert in the Netherlands and to verify the possible sources responsible for these processes