Alkali cation induced liquid crystalline properties of an oligophenylenevinylene-benzocrown ether conjugate

An oligophenylenevinylene-benzocrown ether conjugate has been prepared and its binding selectivity for alkali metal ions evaluated by electrospray mass spectrometry. Whereas this benzocrown-ether derivative does not exhibit any liquid crystalline properties, the self-assembly by coordination to potassium or cesium leads to supramolecular sandwich complexes with mesomorphic properties.     

The uncertainty of the chemical sample preparation is part of the uncertainty of the measurement result

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On quantum multi-hamiltonian systems

On studying various examples with one degree of freedom, we discuss the possibility of extending the classical concept of multi-Hamiltonian systems to the quantum domain. We show that an adaptation is possible in each case generally leading to distinguish classes of systems characterized globally by their observable algebras.     

Compactification équivariante d’un tore (d’après Brylinski et Künnemann)

We give a combinatorial, self-contained proof of the existence of a smooth equivariant compactification for an algebraic torus defined over an arbitrary field.     

NoteA 16-vertex tournament for which Banks set and Slater set are disjoint

Given a tournament T, a Banks winner of T is the first vertex of any maximal (with respect to inclusion) transitive subtournament of T; a Slater winner of T is the first vertex of any transitive tournament at minimum distance of T (the distance being the number of arcs to reverse in T to make T transitive). In this note, we show that there exists a tournament with 16 vertices for which no Slater winner is a Banks winner. This counterexample improves the previous one, due to G. Laffond and J.-F. Laslier, which has 75 vertices.     

Irradiation effects detected by Mössbauer spectroscopy in iron complexes

The nature and the extent of the ⁶⁰Co gamma radiolysis of several iron coordination compounds have been analysed by Mössbauer absorption spectroscopy. The comparison of the radiolytic yields with the after effects observed by Mössbauer emission spectroscopy in similar ⁵⁷Co‐doped compounds, supports the self‐radiolysis model.