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Using nuclear power for civil energy generation was a promising idea in the second half of the 20th century. Compared to fossil fuels, nuclear power results in almost no $\mathrm{CO}_{2}$ bearing emissions, which are known to have triggered and enhanced the global climate change. However, nuclear power bears other risks, e.g. environmental and health damage caused by radiation, unwanted release of nuclides being transported by water, accidents of nuclear power plants, and not to mention the possibility of non-intended military use. In any case, generating power from nuclear fission will always produce radiating waste, albeit in small amounts. Due to its longevity, this waste is a significant challenge for scientists, politicians and for the international social community to find a repository, which can be considered safe for millions of years and is accepted by the public. As the general consensus is that the rocks of earth crust’s are the best option for a controlled storage, scientists including geologists, geophysicists and hydrogeologists are looking worldwide for safe underground repository sites. Given different political preconditions, the nations, especially in the European Union, have developed different strategies. The following article intends to describe the current strategy in Germany, which is based on a specific “Act on the search for and selection of a site for a final repository for highly radioactive waste” (in short: Site Selection Act) and attempts to learn from mistakes in the seventies. It is our strong conviction that fundamental geological aspects are as important as essential societal principles in order to gain maximum public acceptance.

A series of hydrogen-bonding catalysts have been designed for the aromatic Claisen rearrangement of a 1,1-dimethylallyl coumarin. These catalysts were designed as mimics of the two-point hydrogen-bonding interaction present in ketosteroid isomerase that has been proposed to stabilize a developing negative charge on the ether oxygen in the migration of the double bond.1 Two hydrogen bond donating groups, a phenol alcohol and a carboxylic acid, were grafted onto a conformationally restrained spirocyclic scaffold, and together they enhance the rate of the Claisen rearrangement by a factor of 58 over the background reaction. Theoretical calculations correctly predict the most active catalyst and suggest that both preorganization and favorable interactions with the transition state of the reaction are responsible for the observed rate enhancement.

A hydroxy-sodalite/cancrinite zeolite composite was synthesized from low-grade calcite-bearing kaolin by hydrothermal alkali-activation method at 160 °C for 6 h. The effect of calcite addition on the formation of the hydroxy-sodalite/cancrinite composite was investigated using artificial mixtures. The chemical composition and crystal morphology of the synthesized zeolite composite were characterized by X-ray powder diffraction, infrared spectroscopy, scanning electron microscopy, and N2 adsorption/desorption analyses. The average specific surface area is around 17−20 m2·g−1, whereas the average pore size lies in the mesoporous range (19−21 nm). The synthesized zeolite composite was used as an adsorbent for the removal of heavy metals in aqueous solutions. Batch experiments were employed to study the influence of adsorbent dosage on heavy metal removal efficiency. Results demonstrate the effective removal of significant quantities of Cu, Pb, Ni, and Zn from aqueous media. A comparative study of synthesized hydroxy-sodalite and hydroxy-sodalite/cancrinite composites revealed the latter was 16−24% more efficient at removing heavy metals from water. The order of metal uptake efficiency for these zeolites was determined to be Pb > Cu > Zn > Ni. These results indicate that zeolite composites synthesized from natural calcite-bearing kaolin materials could represent effective and low-cost adsorbents for heavy metal removal using water treatment devices in regions of water shortage.

We demonstrate functionalized spiroligomers that mimic the HDM2-bound conformation of the p53 activation domain. Spiroligomers are stereochemically defined, functionalized, spirocyclic monomers coupled through pairs of amide bonds to create spiro-ladder oligomers. Two series of spiroligomers were synthesized, one of structural analogs and one of stereochemical analogs, from which we identified compound 1, that binds HDM2 with a Kd value of 400 nM. The spiroligomer 1 penetrates human liver cancer cells through passive diffusion and in a dose-dependent and time-dependent manner increases the levels of HDM2 more than 30-fold in Huh7 cells in which the p53/HDM2 negative feed-back loop is inoperative. This is a biological effect that is not seen with the HDM2 ligand nutlin-3a. We propose that compound 1 modulates the levels of HDM2 by stabilizing it to proteolysis, allowing it to accumulate in the absence of a p53/HDM2 feedback loop.