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During the past few years, the feasibility of using polymer electrolyte fuel cells in automotive power trains at an impressive performance level has been proven repeatedly. However, current fuel cell stacks are still largely based on decade‐old polymer electrolyte membrane technology thus limiting performance, durability, reliability, and cost of the fuel cell systems. The major challenge for membrane R&D constitutes the demand for polymer electrolytes that allow for system operation at higher temperatures and lower water management requirements without increased conduction losses. None the less, demanding automotive requirements will not compromise on other properties such as mechanical and chemical stability and gas permeability.

The complexing, extracting and mobile carrier properties of the tetra(phosphine oxide)-calix[4]arene 1 and the hybrid diamide-di(phosphine oxide)-calix[4]arene 2 were studied. Both ligands give 1 : 1 complexes with alkali cations in THF as shown by the picrate method. 1H NMR experiments were run to follow encapsulation of sodium and potassium cations. The corresponding spectra indicate C2-symmetrical structure. The observed extraction orders of the alkali picrates were as follows K+>Rb+>Li+>Cs+>Na+ for 1 and Li+>Na+>K+>Rb++ for 2. Transport kinetics was analysed by means of a model which assumes pure diffusion and which allows the evaluation of mass transfer coefficients in all systems. These coefficients and their influences on the transport rate are discussed in terms of size of the transporting species in the liquid membrane.

Zusammenfassung Die primäre, d. h. direktë ödér ungestorte Knoehenbruchheilung bei stabiler Osteosynthese wirkt sich im Röntgenbild “negativ” aus durch Verschwinden des Frakturspaltes und Fehlen von weiteren Knochenveränderungen. Jeder sichtbare Knochenzuwachs und jede Osteolyse sind (mit Ausnahme der erst später auftretenden Metallose) der Ausdruck einer verzögerten und gestörten primären Knochenheilung, deren Schweregrad und Ursache rechtzeitig erkannt werden müssen, um unter Umständen schwere Mißerfolge zu vermeiden.

A fully parameterized microscale model for lithium ion cells is presented in which the solid and pores (filled by electrolyte) are spatially resolved, and the mass and charge transport equations describing diffusion and migration in each phase are solved separately. Such a model allows: (1) the correlation of structure-scale, non-homogeneous material properties with macroscopic battery performance, and (2) the correlation of geometrical electrode morphology with macroscopic battery performance (electrode design). The micro-model approach discussed here allows for a simpler parameterization as fewer constitutive relations are needed in contrast to the macro-homogenous physical-based approaches. Input parameters were measured experimentally on lithium manganese oxide electrodes and LiPF6in 3:7 EC:DMC. Verification and validation for the model is also reported.