J. Efer

Trace determination of priority pesticides in water by means of high-speed on-line solid-phase extraction–liquid chromatography–tandem mass spectrometry using turbulent-flow chromatography columns for enrichment and a short monolithic column for fast liquid chromatographic separation

Arndt Asperger, J. Efer, Therese Koal et al. · Journal of Chromatography A · 2002 · 132 citations

Engineering, Pesticide-residue Analysis, Environmental Engineering +10

Application of spectral libraries for high-performance liquid chromatography–atmospheric pressure ionisation mass spectrometry to the analysis of pesticide and explosive residues in environmental samples

André Schreiber, J. Efer, W. Engewald · Journal of Chromatography A · 2000 · 83 citations

Environmental Chemistry, Engineering, Pesticide-residue Analysis +12

On the signal response of various pesticides in electrospray and atmospheric pressure chemical ionization depending on the flow-rate of eluent applied in liquid chromatography–tandem mass spectrometry

Arndt Asperger, J. Efer, Therese Koal et al. · Journal of Chromatography A · 2001 · 59 citations

Environmental Chemistry, Engineering, Various Pesticides +13

Programmed temperature vaporisers-based large volume injection in capillary gas chromatography

W. Engewald, Jörg Teske, J. Efer · Journal of Chromatography A · 1999 · 49 citations

Capillary Gas Chromatography, Engineering, Supercritical Fluid Chromatography +7

Simultaneous determination of a wide spectrum of pesticides in water by means of fast on-line SPE-HPLC-MS-MS—a novel approach

Therese Koal, Arndt Asperger, J. Efer et al. · Chromatographia · 2003 · 49 citations

Engineering, Pesticide-residue Analysis, Environmental Engineering +11