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Abstract  

Some examples are given for illustrating the isotope dilution and labelled derivatization techniques in the analyses of fatty acids.

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Morphological identification of larvae and adults of the EU quarantine pest Thrips palmi is one of the routine procedures of the National Reference Laboratory (NRL) of the Dutch Plant Protection Service. The quality of a morphological identification depends on several technical requirements, most important of which are laboratory facilities, literature, reference collection, quality of the available specimen(s) and skills of the specialist. To be able to consistently produce valid identification results, the NRL has implemented a documented quality management system within the laboratory since 2007. ISO/IEC 17025 is used to demonstrate our competence on Thrips palmi identification under a fixed scope, “Morphological identification of T. palmi adults”. The EPPO PM 7/98 guidance for entomology sets specific requirements for this process to enable the validation of morphological identification of T. palmi adults. It is concluded that of the requirements “selectivity” can be applicable for T. palmi samples and “repeatability” is very difficult to measure for the lack of fresh samples with look-alikes. T. palmi is a well-defined species, but for species which are taxonomically “in disdussion” this guidance cannot be used and validation is not an option. The validity of identifications in entomology should be focused more on confirmation of identifications instead on the validity of a work instruction.

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Abstract  

The effects of flame retardants such as hydrated aluminium oxide, antimony trioxide and chloroparaffin on the thermal properties and flammability of sulphur vulcanizates of butyl and halogenated butyl elastomers were studied. The thermoanalytical curves of the elastomers were interpreted. Greater tendencies to thermal degradation were observed for halogenated butyl elastomers than for the original butyl rubber elastomer. This was confirmed by elastomer combustibility studies. The use of these flame retardants allowed the formation of self-extinguishing vulcanizates of the investigated elastomers.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Glatz
,
I. Garcia-Alonso
,
T. Kameyama
,
L. Koch
,
G. Pagliosa
,
T. Tsukada
, and
H. Yokoyama

Abstract  

In order to study the dissolution behavior of a highly burnt LWR fuel, a fuel pin irradiated in the DR3 test reactor in Risoe National Laboratory, has been characterized by microstructural examination and then dissolved under PUREX type conditions. The dissolution behavior was investigated and the residues analyzed by scanning electron microscopy and by ICP-MS and IDMS after dissolution.

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The pathogenesis of chicken infectious anaemia virus (CAV) infection was studied in 6-week-old and one-day-old SPF chickens inoculated intramuscularly with graded doses of Cux-1 strain (106−102 TCID50/chicken). Viraemia, virus shedding, development of virus neutralizing (VN) antibodies and CAV distribution in the thymus were studied by virus isolation, polymerase chain reaction (PCR), immunocytochemistry (IP) and in situ hybridization until postinfection day (PID) 28. In 6-week-old chickens infected with high doses of CAV, viraemia and VN antibodies could be detected 4 PID and onward without virus shedding or contact transmission to sentinel birds. However, virus shedding and contact transmission were demonstrated in one-day-old infected chickens. In the 6-weekold groups infected with lower doses, VN antibodies developed by PID 14, transient viraemia and virus shedding were detected. The thymus cortex of all 1-dayold inoculated chickens stained with VP3-specific mAb. Cells with positive in situ hybridization signal were fewer and scattered throughout the thymus tissue of the one-day-old inoculated chickens as compared to IP-positive cells. These results suggest that early immune response induced by high doses of CAV in 6-week-old chickens curtails viral replication and prevents virus shedding.

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