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Long-term sustainability and decreasing amount of fossil oil reserves require a partial or complete transformation of traditional lubricating oils. The use of silica nanoparticles as a lubricant additive has a huge tribological potential, which has already been discussed in numerous articles. Nanosized silica shows excellent results in reducing friction and preventing wear, but they quickly aggregate and settle after homogenization in oils. For long-term stable dispersion of lubricating oils containing nanoceramics, the surface of the particles was modified with ethyl oleate. The surface modification, the ethyl oleate applied to the surface of the nanosilica, was confirmed by Fourier-transform infrared spectroscopy. Group III based lubricating oil was prepared using the surface-modified nanosilica. The particle size of the nanoparticles in the lubricating oil dispersion was examined by dynamic light scattering. Oscillating tribometer measurements were performed with different concentrations (0.1; 0.2; 0.3 wt%) of nanolubricants. Based on the tribological results, the friction coefficient of the surface-modified nanosilica is more stable, its wear is 15% lower compared to the reference. There is no significant change in the magnitude of the friction coefficient. It can be concluded that the ethyl oleate surface modification method may be suitable for tribological investigations of the acting mechanisms of nanoparticles.

The most high profile transboundary water dispute to ever reach the International Court of Justice -the Gabčí-kovo-Nagymaros case -remains unresolved 18 years after the delivery of the judgement. This article suggests that there are at least three structural causes that prevent the parties -Hungary and Slovakia -from coming to an agreement. First is the judgement of the Court itself that has created an ambiguous legal situation that actually helped the parties to reinforce their pre-litigation positions. Second, the Gabčíkovo-Nagymaros dam complex gained an unexpectedly powerful symbolic value in both countries whose antagonistic nature still holds a strong grip on the two governments. Finally, these circumstances have given rise to a negotiating dynamic that is characterised by mutual distrust and dominated by the fear of loss. Consequently, while both countries are aware of what the final outcome should and could be, they are unable to get there as the lack of consensus on the starting conditions of the negotiations and the domestic political domain leaves almost no space for rational concessions. The Gabčí-kovo-Nagymaros case is therefore likely to remain unresolved, unless the parties manage to find a new positive negotiating paradigm that subsumes the old rivalry of the underlying dam dispute.

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