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The gas-phase reactions of sulphur cluster ions, cations S+n (n=1,...,8) and anions S−n (n=2,...,6) with NH3 have been studied by means of a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Relative and absolute reaction rate constants as well as reaction efficiencies have been determined. The S+4 cation has by the far highest reactivity with all other sulphur cations being significantly less reactive. Besides some fragmentation, no reactivity of the anions was found. Structural conclusions are made based on the present experiments, on previous extensive ab initio calculations, and on complementary experiments.

The design of a desalination plant is most important if the desired product purity has to be as high as possible. This is also true for freeze crystallization plants. A correct solid-to-liquid ratio has to be ensured when pressing is used as a post-treatment. Thus, the dependence of the overall plant design on the achieved ice quality but also on different hydraulic and thermodynamic numbers is important. In this research, a scraped screw crystallizer plant is presented and examined for two different screw designs. Experiments with a low initial concentration, as for the usage to desalinate groundwater to gain it as process water, were conducted. Furthermore, solutions with high initial concentrations simulating seawater to produce potable water were used as another set of test solutions. The findings showed that neither of the screw designs is more favorable than the other, but it is important to have a plant design fitting the existing parameters on site.

Investigating switchable vacuum insulation panels might lead to a new type of insulation, which can be switched on to enable a low heat flow when a good insulation effect is desired and switched off when exchange with the environment is requested, during a cold summer night, for example. For this reason, different core materials for vacuum insulations as typical silica powder were investigated as well as silica agglomerates and silica gel. These materials were checked for the necessary time of aeration and evacuation and the corresponding change of heat conductivity along with the change of gas-pressure. Silica gel in combination with helium as filling gas showed best results corresponding to a high difference of the heat conductivities evacuated and aerated. Beside the solid backbone structure of the silica gel, this is caused by the high heat conductivity and small kinetic atomic diameter of the helium gas. Silica agglomerates decreased the aeration time as well as the deaeration time, but the improvement was neglected because of a lower change of heat conductivity during pressure drop or rise. Nevertheless, a good switchable vacuum insulation can be produced using silica gel and helium, for example.