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Three institutes of the Universities of Applied Sciences that are active in Chemistry and Life Sciences present a selection of their activities in the field of environmental sciences. These projects include analytical monitoring, removal of micropollutants, waste reduction and valorization.

The corrosion behavior of shotcrete in the safety gallery of the motorway tunnel Gotthard was investigated. The tunnel was built in 1972/73, sections with waterleading rocks show various signs of concrete degradation. Samples of corroded concrete were investigated in the laboratory for their chemical and mineralogical compositions. X-ray diffraction (XRD), X-ray fluorescence (XRF), and methods to determine acid-soluble silicon compounds and insoluble contents were used to characterize the samples.Comparisons of original concrete with corroded samples show the existence of discrete interaction mechanisms. These mechanisms lead either to harmless efflorescence, to detachments of concrete from the rock or to more or less complete degradation of the cement paste. Delamination or deterioration of concrete are related to the amount and kind of transformation products formed due to action of specific ionic species of the interacting water. Special attention is drawn to the formation of thaumasite, which may be formed under special conditions, even when sulfate-resistant cements have been used.Physical and chemical properties of the cement paste as well as the composition of interacting water are important for the service life of a concrete structure. The potential of concrete degradation due to interaction with aggressive water may be lowered by preventing its contact or by draining the water not to force it to penetrate the concrete structure.

Some applications of Analytical Electron Microscopies (AEM) for the characterization of colloids in natural waters are presented. These techniques go much beyond the basic level of morphological observation and render possible to gain detailed physico-chemical information difficult to obtain by conventional analytical methods. Hence, AEM appear as a challenging necessity for understanding the colloid-mediated transport of toxics in the environment.

Modern analytical chemistry relies on a multiplicity of different instrumental methods, their ranges of application being partially overlapping, partially supplementary. The universally utilizable dream method, which solves all possible problems does not exist. Nevertheless, every existing instrumental analytical method can be described as a modular composition including three steps: provocation, reaction, and detection. Based on this concept, the irritating multiplicity of existing analytical methods can be well surveyed.

Three institutes of the Universities of Applied Sciences that are active in Chemistry and Life Sciences present a selection of their activities in the field of environmental sciences. These projects include analytical monitoring, removal of micropollutants, waste reduction and valorization.