Surface topography of the Greenland Ice Sheet from satellite radar altimetry

Surface elevation maps of the southern half of the Greenland subcontinent are produced from radar altimeter data acquired by the Seasat satellite. A summary of the processing procedure and examples of return waveform data are given. The elevation data are used to generate a regular grid which is then computer contoured to provide an elevation contour map. Ancillary maps show the statistical quality of the elevation data and various characteristics of the surface. The elevation map is used to define ice flow directions and delineate the major drainage basins. Regular maps of the Jakobshavns Glacier drainage basin and the ice divide in the vicinity of Crete Station are presented. Altimeter derived elevations are compared with elevations measured both by satellite geoceivers and optical surveying

In-situ Clean-up and OPLC Fractionation of Chamomile Flower Extract Searching Active Components by Bioautography

Bioassay-guided isolation of antibacterial components of chamomile flower methanol extract was performed by OPLC with on-line detection, fractionation combined with sample clean-up in-situ in the adsorbent bed after sample application. The antibacterial effect of the fractions and the separated compounds remained on the adsorbent layer (do not overrun during OPLC separation) was tested with direct bioautography (DB) against the bioluminescent Pseudomonas savastanoi pv. maculicola and Vibrio fischeri. The fractions with great biologically activity were analysed by SPME-GC-MS and LC-MS/MS and the two active uneluted compounds were characterized by OPLC-MS using interface. Mainly essential oil components, coumarins, flavonoids, phenolic acids and fatty acids were identified in the fractions