90 research outputs found
Atmospheric sources, transport and deposition of mercury in Michigan: Two years of event precipitation
To assess the sources, transport and deposition of atmospheric mercury (Hg) in Michigan, a multi-site network was implemented in which Hg concentrations in event precipitation and ambient samples (vapor and participate phases) were determined. Results from the analysis of 2 years of event precipitation samples for Hg are reported here. The volume-weighted average Hg concentration in precipitation was 7.9, 10.8 and 10.2 ng/L for the Pellston, South Haven and Dexter sites, respectively. Yearly wet deposition of Hg for 1992–93 and 1993–94 was 5.8 and 5.5 μg/m 2 at Pellston, 9.5 and 12.7 μg/m 2 at South Haven and 8.7 and 9.1 μg/m at Dexter. A spatial gradient in both the Hg concentration and wet deposition was observed. Northern Michigan received almost half the deposition of Hg recorded at the southern Michigan sites. The concentration of Hg in precipitation exhibited a strong seasonal behavior with low values of 1.0 to 2.0 ng/L in winter and maximum values greater than 40 ng/L in summer. The spring, summer and autumn precipitation accounted for 89 to 91% of the total yearly Hg deposition. Mixed-layer back trajectories were calculated for each precipitation event to investigate the meteorological history and transport from potential Hg source regions. Elevated Hg concentrations were observed with air mass transport from the west, southwest, south, and southeast. At each of the sites precipitation events for which the Hg concentration was in the 90th and 10th percentile were-analyzed for trace elements by ICP-MS to investigate source impacts.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43912/1/11270_2005_Article_BF01189668.pd
Removal of Noise by Wavelet Method to Generate High Quality Temporal Data of Terrestrial MODIS Products
Bio-analytical Assay Methods used in Therapeutic Drug Monitoring of Antiretroviral Drugs-A Review
The preparation of mono-and di-[2-nitro-4-(1,1,3,3-tetramethylbutyl) phenyl]-phosphoric acids and their calcium salts for use in PVC calcium ion selective electrodes
A modified preparative procedure for di-n-octylphenylphosphonate mediator used in calcium ion selective electrode membranes
Potentiometric Graphite Coated Electrode Based on Ditertbutyl-cyclohexano18crown6 for Detection of Strontium (II) Ions
The preparation of mono- and di-[4-(n-octyl)phenyl]- and -[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acids for use in PVC calcium ion-selective electrodes
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