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Durch Oxydation silylierter bzw. germylierter Trimethylstannyl-organyl-hydrazine, z.B. des Typs (Me3Sn)RN—N(EMe3)(SnMe3) (R Me, CMe3, Ph; E Si, Ge), mit p-Benzochinon (bzw. weniger vorteilhaft mit Sauerstoff) entstehen in hohen Ausbeuten silylierte und germylierte Organyldiimine R—NN—EMe3. Stannylierte Organyldiimine (E Sn) konnen auf diesem Reaktionsweg nicht gewonnen werden. Uber die Darstellung der fur die Oxydation benotigten substituierten Organylhydrazine wird berichtet. On Derivatives of Hydrazine, 3 Preparation and Oxidation of Silylated, Germylated, and Stannylated Hydrazines and Organylhydrazines Oxidation of silyl- or germyl-substituted (trimethylstannyl)-organylhydrazines [for example (Me3Sn)RN—N(EMe3)(SnMe3); R Me, CMe3, Ph; E Si, Ge] with p-benzoquinone (or, less advantageously, with oxygen) affords silyl- and germyl-substituted diimines R–NN–EMe3 in high yields. Stannyl-substituted organyldiimines (E Sn) could not be prepared in this way. Methods for the preparation of the substituted organylhydrazines used for the oxidation reactions are reported.

The three main water circuits of the Gösgen pressurized water reactor and their chemistries are described. In the primary water circuit the cooling water and its contents undergo chemical as well as radiochemical reactions. Chemical agents – such as boric acid – are used for long-term reactivity control. The boron concentration therefore is dictated by reactor physics and may not be optimal from a chemical viewpoint. Under the given circumstances the chemistry of the primary water circuit cannot be adjusted to a sole optimum covering all the tasks. Nevertheless it is possible to operate the power plant using a chemical regime that avoids excessive corrosion within the expected plant live time of 60 years. The water-steam cycle with its two phases must be conditioned chemically in a way to protect the water and steam side components from corrosion. This is done by adding hydrazine to remove oxygen and to form ammonia, which is the main contributor to water alkalinisation. The cooling water system is open to the atmosphere and supplied by river water with continually changing contents. To avoid deposits on the system surfaces an upstream water treatment plant is used to remove suspended matter and to precipitate calcium and magnesium. Thousands of tons of chemicals are needed to treat the required 20 billions of litres of water each year. Radioactive waste treatment plays an important role in the nuclear industry. Operational waste is divided into three waste streams. Only one of these waste streams (waste water) is really influenced by water chemistry.

Nitrosomonas europea and Nitrosovibrio sp. produced NO and N sub 2 O during nitrification of ammonium. Less than 15 % of the produced NO was due to chemical decomposition of nitrite. Production of NO and especially of N sub 2 O increased when the bacteria were incubated under anaerobic conditions at decreasing flow rates of air, or at increasing cell densities. Low concentrations of chlorite (10 myM) inhibited the production of NO and N sub 2 O, but not of nitrite indicating that NO and N sub 2 O were not produced during the oxidative conversion of ammonium to nitrite. NO and N sub 2 O were produced during reduction of nitrite with hydrazine as electron donor in almost stoichiometric quantities indicating that reduction of nitrite was the main source of NO and N sub 2 O.