0000000000590037
AUTHOR
T. A Ternes
UV-Filtersubstanzen in Wasser und Fischen
Zur Erfassung der UV-Filtersubstanzen wird eine Methode vorgestellt, die die simultane Bestimmung dieser Verbindungen und von Organochlorverbindungen wie PCB und DDT in unterschiedlichen Fischkompartimenten bis in den ng/kg-Bereich ermoglicht. Die Nachweisgrenzen liegen zwischen 40 und 90 ng/kg Filet und die Wiederfindungsraten bewegen sich zwischen 78 und 104%. Die Belastung von Wasser und Fischen des Meerfelder Maares, Eifel, mit UV-Filtersubstanzen wurde 1991 und 1993 exemplarisch untersucht. Insgesamt konnten in den Fischen des Meerfelder Maares 6 UV-Filtersubstanzen identifiziert und quantifiziert werden. Die im Sommer 1991 gefangenen Barsche waren mit 2,0 mg/kg Fett (Summe nachgewiese…
Contributions to the analysis of organic xenobiotics in fish
For the residue-analysis of fish samples, a method has been developed to separate the medium polar triazines and acetamides together with lipophilic xenobiotics (organochlorine pesticides, PCBs and octachlorostyrene) from fish tissue. The detection limits of the analytes are mostly within the ppt-range (ng/kg fillet) and vary between 40 and 1050 ng/kg fillet of fish. Their recoveries range from 75 to 108%, spiked at 1.5 μg/kg. The substances are extracted with a mixture of petroleum ether/ethylacetate (2:1) using a soxhlet apparatus. Subsequently, the lipids in the sample extracts are reduced to 0.4% by gel chromatography. A 5 g silica gel clean-up separates the analytes according to their …
AES and CEMS analysis of the formation of layers on Si steel under thermal treatment in a flux of H2/water vapour
The near surface diffusion and reaction processes in iron-silicon steel (3.1 wt.%Si) during 10 min decarburization in water vapour/hydrogen have been studied. The decarburization temperature has been varied between 506 and 714°C for the fixed partial pressure ratio pH2O/pH2=0.017. An outer layer of SiO2 forms on the surface with its thickness increasing with temperature. From 600°C upwards, the decarburization process is hindered and a cementite layer is formed below the SiO2 layer. The formation of fayalite at the surface has been studied at a fixed decarburization temperature with pH2O/pH2 ranging from 0.017 to 0.49. The scale thickness reduces abruptly just before the ratio pH2O/pH2 nece…