Currently, a lot of research effort in polymer analysis by liquid chromatographic techniques, including size exclusion chromatography (SEC), polymer HPLC or liquid chromatography at critical conditions, is done aiming to improve separation performance. In this study, novel gradient protocols were investigated primarily based on gradient polymer elution chromatography (GPEC). Starting with linear gradients and stepwise gradients a new periodic saw tooth gradient profile was developed and optimized.
View Article and Find Full Text PDFThe age determination of elephant ivory provides necessary and crucial information for all criminal prosecution authorities enforcing the Convention on International Trade in Endangered Species of Wild Fauna and Flora. The knowledge of the age of ivory allows to distinguish between pre-convention, hence legal material and ivory deriving from recent, illegal poaching incidents. The commonly applied method to determine the age of ivory is radiocarbon dating in the form of bomb pulse dating, which however will fade out soon.
View Article and Find Full Text PDFThe adaption of an parallel-path poly(tetrafluoroethylene)(PTFE) ICP-nebulizer to an evaporative light scattering detector (ELSD) was realized. This was done by substituting the originally installed concentric glass nebulizer of the ELSD. The performance of both nebulizers was compared regarding nebulizer temperature, evaporator temperature, flow rate of nebulizing gas and flow rate of mobile phase of different solvents using caffeine and poly(dimethylsiloxane) (PDMS) as analytes.
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