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Research about Dover, Delaware

Source-linked reports with geographic coverage including Dover, Delaware.

2 recordsLinked to original sources

Comparison of two cell lysis procedures for recovery of microcystins in water samples from silver lake in Dover, Delaware, with microcystin producing cyanobacterial accumulations

A collaboration was developed between Abraxis, LLC, the State of Delaware Department of Natural Resources and Environmental Control Division of Water Resources Environmental Laboratory, the University of Delaware, and the United States Geological Survey to investigate the efficacy of the QuikLyse procedure developed by Abraxis, LLC as an alternative cell-lysis technique suitable for use with an existing liquid chromatography/tandem mass spectrometry research method developed at the United States Geological Survey Organic Geochemistry Research Laboratory to analyze cyanotoxins. A comparison of three sequential freeze/thaw cycles versus QuikLyse, a proprietary chemical lysis procedure was conducted on four water samples collected from Silver Lake in Dover, Delaware. Results from the Abraxis Microcystins-DM enzyme-linked immunosorbent assay and liquid chromatography/tandem mass spectrometry were tabulated as a function of the cell lysis technique. Stastical comparison of percent relative standard deviations showed no significant difference (alpha = 0.05) between both cell-lysis techniques when measured by enzyme-linked immunosorbent assay or liquid chromatography/tandem mass spectrometry for three of the four samples.

Delaware

Combined use of digital aquifer models and field base-flow data to identify recharge-leakage areas of artesian aquifers

As a result of continuous pumping since the 1890's, a regional cone of depression encompassing 363 km 2 has developed within the artesian Miocene Cheswold aquifer at Dover, Del. The aquifer is not being recharged significantly by leakage near the center of the cone, nor is major recharge induced in the updip subcrop area. The source of pumped water is apparently an area of about 65 km 2 northwest of Dover, where vertical leakage is substantial. This area was delineated by use of a digital aquifer model and streamflow data. A model of the unconfined aquifer was used to compute the unconfined aquifer's natural discharge to streams, assuming no leakage to underlying artesian aquifers. The area of substantial leakage to the underlying Cheswold was delineated as being coincident with that area where model-computed values of stream discharge were substantially larger than actual values of stream discharge determined in the field.

Delaware