Verfahren zur Holzschutzmittelbestimmung. Statistik der Probenahme und Analytik der Holzschutzmittel in Altholz

A standardized and validated procedure was established for the sampling of single wood pieces and for the analytical investigation of selected preservative agents in single wood pieces and shreddered wood chips. The investigations were carried out with an authentic reclaimed inhomogenic wood assortment from house demolition obtained from a recycling plant. A safe quantitative determination of 80 components is possible with the proposed method. We compared the quantities of the preservative agents form the single wood with the preservative agent contents of the sorted and shreddered wood chips. We developed a concentration-level model for the general assessment of pollution in wood wastes. It includes three concentration ranges for naturelike, contaminated and treated wood. The first threshold value shows the concentration of naturelike wood. The second threshold value separates the categories of treated and contaminated wood derived from published data under consideration of washout and evaporation processes. (orig.)Available from TIB Hannover: RN 8908(99-081) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEUmweltbundesamt, Berlin (Germany); Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Bonn (Germany)DEGerman

Chip-Based High-Performance Liquid Chromatography for High-Speed Enantioseparations

In this work, the first high-performance chiral liquid chromatography in packed microfluidic chips is presented. The chromatographic separation was performed on a column integrated into the microfluidic glass chip and packed with the particulate chiral stationary phase. Cellulose tris­(3,5-dimethylphenylcarbamate) coated on 5-μm fully porous silica was used as chiral stationary phase material. Several racemic analytes including pharmaceutical products were baseline separated into their corresponding enantiomers under reversed-phase, polar organic and normal-phase conditions, demonstrating the versatility of the glass chip in the field of chiral separations. Van Deemter plots revealed a reduced plate height of 2.2 and a trend to enhanced mass transfer processes for solutes under low retention conditions. The utilization of very short column lengths of down to 12 mm led to ultrafast separations of enantiomers within 5 s

HPLC-MS with Glass Chips Featuring Monolithically Integrated Electrospray Emitters of Different Geometries

We present and evaluate an approach for coupling liquid chromatography in glass chips with mass spectrometry via fully integrated electrospray emitters. We developed an instrumental platform which allows a robust and reproducible operation of high performance chip chromatography coupled to mass spectrometry. A comparison of differently shaped emitters, from flat over edged to pulled geometries, revealed that all types performed equally well for typical nano-HPLC flow rates. At very low flow rates below 50 nL·min^–1 very sharp, pulled nanospray emitters turned out to be mandatory for the generation of a stable electrospray