Showing papers by "Swiss Federal Institute of Aquatic Science and Technology published in 1984"
TL;DR: The photo-oxygenation of furfuryl alcohol (FFA) in water sensitized by naturally occurring dissolved organic materials under visible light is shown to proceed almost exclusively by a singlet oxygen mechanism.
354 citations
TL;DR: In this paper, a reaction scheme was proposed in which bromide is oxidized to HOBr, which then brominates ammonia to produce NH2Br. NH 2Br in turn reacts with O3 to form NO3− and also to generate Br−, which thus acts as a catalyst.
112 citations
TL;DR: In this article, the authors showed that assuming a constant quantum yield measured at a short wavelength can overestimate the 1O2 concentration in sunlit surface waters by more than a factor of 2.
106 citations
TL;DR: In this paper, high-resolution gas chromatography of the butylated acids isolated on an anion exchange resin was used to identify Nitrilotriacetic acid in waters and waste-waters.
48 citations
01 Nov 1984-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: In this article, the authors investigated extractable organic matter (lipids) and hydrocarbons isolated from lake sediments by directly evaporating the extracts onto targets, and the results were in good agreement with results from pollen stratigraphy.
Abstract: Extractable organic matter (lipids) and hydrocarbons isolated from lake sediments were investigated by AMS by directly evaporating the extracts onto targets. Carbon-14 ages obtained for the postglacial sediments of Lake Baldegg (Switzerland) are in good agreement with results from pollen stratigraphy. The hydrocarbons contained in modern sediments of Lake Constance were found to be largely of fossil origin.
37 citations
TL;DR: Based on 20 months of pilot experience the following aspects of operation of a nitrifying tertiary trickling filter are discussed: Biomass production, biomass predation, approach to steady state, load variation, alkalinity, stability of performance, nitrite, temperature and nitrification in multi media filtration as discussed by the authors.
28 citations
TL;DR: Qualitative determinations of volatiles from a secondary sewage effluent were in good agreement with the results found by two more established methods.
24 citations
01 Jan 1984
TL;DR: In this article, the longitudinal concentration and load profiles found in the Glatt River indicated that all of these micropollutants are mainly introduced into the river via treated wastewater effluents.
Abstract: Pentachlorophenol, 2,3,4,6-tetrachlorophenol, 4-nonylphenol, 4-nonyl-phenolmonoethoxyl ate, 4-nonylphenoldiethoxylate, tetrachloroethylene and 1,4-dichlorobenzene were quantitatively determined in surface waters of the Glatt Valley, Switzerland. Monthly samples were collected during one year from four locations along the Glatt River, from two small creeks and from the effluents of two municipal wastewater treatment plants. The longitudinal concentration and load profiles found in the Glatt River indicated that all of these micropollutants are mainly introduced into the river via treated wastewater effluents. The highly chlorinated phenols remain unchanged in the river, while the other pollutants are affected by various physico-chemical and biological processes. Depth profiles of tetrachloroethylene in the Greifensee, the lake which feeds the Glatt, showed that this compound was eliminated from the epilimnion by transfer to the atmosphere and by discharge into the Glatt River.
21 citations
TL;DR: In this article, a method for the analytical fractionation of dissolved organic matter (DOM) in natural freshwater and in used waters is described, based on the different adsorption behaviours of various constituents of the DOM on octadecyl-silica as a function of pH.
17 citations
01 Dec 1984
TL;DR: Comparisons with past plankton analyses revealed a rapid increase of the herbivorous crustaceans, i.e. by a factor of five; while simultaneously, the favourite food (nannoplankton) only increased from 3.1 g/m2 to 5.5 g/ m2 wet weight.
Abstract: In order to create a common comparative biomass basis for the biological interactions between zooplankton and phytoplankton, zooplankton was quantitavely sampled at close intervals, counted and measured at determined development stages. The volumetric values calculated according to stereometric formulas do not indicate an important variability over the years. Significant volume increases of adult crustaceans were observed only from March till May. Comparisons with past plankton analyses revealed a rapid increase of the herbivorous crustaceans, i.e. by a factor of five; while simultaneously, the favourite food (nannoplankton) only increased from 3.1 g/m2 to 5.5 g/m2 wet weight.
7 citations
TL;DR: The first full-scale contact filtration plant for advanced phosphorus removal in Switzerland was built 1979 as mentioned in this paper, which provided consistently low phosphorus and suspended solids levels at reasonable cost.
01 Jan 1984
TL;DR: The combined use of high-performance liquid chromatography and high-resolution gas chromatography offers many advantages for the analysis of complex mixtures of organic chemicals commonly encountered in environmental samples as mentioned in this paper.
Abstract: The combined use of high-performance liquid chromatography (HPLC) and high-resolution gas chromatography (HRGC) offers many advantages for the analysis of complex mixtures of organic chemicals commonly encountered in environmental samples. Of particular benefit is the complementary application of normal- and reversed-phase separation systems in HPLC and the use of HPLC as a preparative separation before detailed analysis by HRGC and HRGC/MS. Several examples of such applications are presented including determinations of polycyclic aromatic hydrocarbons, oil hydrocarbons, alkyl phenols and alkylphenolpolyethoxylates.
01 Dec 1984
TL;DR: In this article, a flow channel which has proved useful for long-term rearing of running water macroinvertebrates is described, through its arena-shaped design and water jet drive, damage to drifting animals is practically excluded.
Abstract: Experiments with running water organisms should be conducted under running water conditions. A flow channel which has proved useful for long-term rearing of running water macroinvertebrates is described. Through its arena-shaped design and water jet drive, damage to drifting animals is practically excluded.
TL;DR: In this article, the adsorption of methylmercury cation, CH3Hg+, on the surface of amorphous silica is strongly pH-dependent and can be described with a single methylmerscury-involved surface equilibrium: SiOH + CH 3Hg+ ⇌ SiOHgCH3 + H+; ★K31 = 10−1.95 at I = 0.1 M NaClO4 and T = 25°C.
01 Jan 1984
TL;DR: The development of glass capillary gas chromatography is reviewed with special emphasis on application to water analysis in this article, where column technology is discussed in detail, in particular with respect to deactivation of columns for direct injection of aqueous solution.
Abstract: The development of glass capillary gas chromatography is reviewed with special emphasis on application to water analysis. Column technology is discussed in detail, in particular with respect to deactivation of columns for direct injection of aqueous solution. In addition, the various injection techniques, their advantages and problems, are summarized. Finally, the relations between commercial and laboratory made columns are discussed.