Sampling site location

In comparison with other studies, which reflect either diffusive pollution or sampling sites located relatively far from the pollution point source, the sampling... 

There are some sampling sites located on mountains that have been used to assess the relative amounts of S02 oxidation that occurs in clouds versus in the gas phase. In these cases, fixed sampling sites can be used and the concentrations of S02, sulfate, and associated species measured in the gas and particle phases as well as in the cloudwater as the cloud passes over the sampling site (e.g., see Saxena and Lin, 1990 Aneja and Kim, 1993 and Burkhard et al., 1995). 

Figure 1. Sampling site locations 1. Merritt Island (E. spicatal 2. Rookery Bay (A- germinans. sea surface, mudflat) 3. Old Ingraham highway ( . jamaicensc) 4. Flamingo (B. maritima) 5. St. Marks ( . alterniflora. I. roemerianus. sea surface, mudflat)...

Cluster I This contains mostly sampling sites located in urban environments (with provisional numbers 122,123, and 126), which are characterized by elevated values of BOD and COD, chlorides, sulfates, calcium, and ammonium. Such site discrimination allows this cluster to be ascribed to the provisional urban site location pattern. In principle, these are sites with elevated levels of anthropogenic pollution. 

Figure 14.12 Typical profiles of (A) beam attenuation coefficient (BAG, from Naqvi et al., 1993) and (B) bacterial abundance (10 cells from Ducklow, 1993) within the denitrifying zone. The sampling sites, located close to each other (around 15°N,67°E) had similar N02 distributions (pM) (C, open circles corresponding to microbial data). Subsequent measurements have confirmed the co-occurrence of these features (Naqvi etal., in preparation).

Figure L Map of the sampling sites. Locations of our study sites are the Science Center in downtown Baltimore (SC) and the Chesapeake Biological Laboratory (CBL). Other sites discussed in the chapter are Elms, Wye and the site in western Maryland, near Frostburg.

Figure IB. Map of Arthur Harbor showing location of the four sampling sites (A, B, Q and D). (Reproduced with permission from reference 46. Copyright 1991 Cambridge.)...

Two line narrowing techniques, matrix isolation and resonant laser excitation, are being used separately and in combination to eliminate inhomogeneous broadening (94). Microenvironmental inhomogeneities are reduced by freezing the sample into uniform site locations in isolation or Shpol skii matrices (95). Alternatively, with highly monochromatic and tunable lasers, it is possible to photoexcite only the subset of emitter sites in a low temperature matrix which have... 

The catalytic activity of hierarchical and conventional Beta zeolites for acylation of 2-MN is displayed in Figure 2(a) The Beta (PHAPTMS) sample shows a superior catalytic activity than the conventional one, due to its enhanced textural properties. In this case, the bulky nature of both substrate and products may cause the existence of diffusional problems inside the zeolitic channels, which are attenuated in the modified Beta sample due to the presence of the hierarchical porosity. Regarding the product distribution (Figure 2(b)), two main products are observed and a third isomer, 8-A,2-MN isomer is produced just in minor amounts. Interestingly, the selectivity towards the desired isomer increases in the material obtained from silanized seeds, reaching values around 75%. Probably, the active sites located on the surface of the secondary porosity are able to catalyze also the formation of 6-A,2-MN by transacylation. However, this reaction is expected to be strongly hindered in the conventional Beta zeolite since it requires the participation of two bulky molecules as reactants. 

The multivariate statistical data analysis, using principal component analysis (PCA), of this historical data revealed three main contamination profiles. A first contamination profile was identified as mostly loaded with PAHs. A samples group which includes sampling sites R1 (Ebro river in Miranda de Ebro, La Rioja), T3 (Zadorra river in Villodas, Alava) and T9 (Arga river in Puente la Reina, Navarra), all located in the upper Ebro river basin and close to Pamplona and Vitoria cities,... 

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