Publications by authors named "F Frimmel"
Article Synopsis
- This study examined how ionic strength and dissolved organic matter (DOM) affect the behavior of TiO nanoparticles in municipal wastewater.
- DOM improved the mobility of nanoparticles by creating repulsive forces, while electrolytes had the opposite effect by neutralizing charges.
- The type of DOM mattered, with proteins like bovine serum albumin enhancing mobility the most, whereas high concentrations of electrolytes could lead to increased particle aggregation.
Mass transfer and biological transformation phenomena in the capillary fringe were studied using phenol, salicylic acid, benzenesulfonic acid, and the iodinated X-ray contrast agent iomeprol as model organic compounds and the microorganism strain Pseudomonas fluorescens. Three experimental approaches were used: Batch experiments (uniform water saturation and transport by diffusion), in static columns (with a gradient of water saturation and advective transport in the capillaries) and in a flow-through cell (with a gradient of water saturation and transport by horizontal and vertical flow: 2-dimension flow-through microcosm). The reactors employed for the experiments were filled with quartz sand of defined particle size distribution (dp=200.
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- The study investigates how anaerobic microbes break down aromatic and heterocyclic compounds in contaminated groundwater, highlighting the formation of specific metabolites as indicators of this process.
- The researchers utilized a novel analytical method involving neutral loss scans and high-resolution mass spectrometry to detect and identify acidic metabolites in water samples from a tar oil-polluted site and a downstream area.
- Several compounds were successfully identified and linked to active biodegradation in the contaminated area, while no significant metabolites were found downstream, suggesting that degradation processes are localized to the pollution site.
This study shows the changes of natural organic matter (NOM) from Lake Hohloh, (Black Forest, Germany) during heterogeneous photocatalysis with TiO2 (TiO2/UV). The effect of pH on the adsorption of NOM onto TiO2 in the dark and TiO2/UV degradation of NOM was followed using three-dimensional excitation-emission matrix (EEM) fluorescence. At pH values between 4 and 9, the NOM was adsorbed onto TiO2 in the dark with a greater decrease in the fluorescence intensity and in the spectral shapes, especially under acidic pH conditions.
View Article and Find Full Text PDFHydraulic fracturing (fracking) is a technique used to release and promote the extraction of natural gas (including shale gas, tight gas, and coal bed methane) from deep natural gas deposits. Among the German public there is great concern with regard to the potential environmental impacts of fracking including the contamination of ground water, the most important source of drinking water in Germany. In the present article the risks of ground water contamination through fracking are discussed.
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