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A-T-Al aluminides (where A = actinide/lanthanide/rare earth elements and T=transition metal) were intensively studied due to their ability to form heavy fermion compounds that could possess unique physical properties [1-3, for example]. Although A-T-Al family contains hundreds of phases, they can be classified into only a few series of phases with isotypical structures. Al richest are: tetragonal ATxAl12-x (ThMn12 type), tetragonal AT2Al10 (CaCr2Al10 type), orthorhombic AT2Al10 (YbFe2Al10 type) and cubic AT2Al20 (CeCr2Al20 type). Due to the intimate link between structure and properties, in order to understand and enhance physical properties – exact atomic structure of these materials should be known. Such researches are performed usually using “trial and error” approach, e.g. cast and characterize, which could be time consuming. It would be of clear benefit to formulate a rule that could predict the relative stability of the structures that may form in the ternary Al-richest phases in the A-T-Al systems.
Current research was conducted with an aim to understand the influence of A and T atom types on the formation of the stable structures in the AT2Al20 alloys. The work was performed systematically, investigating several AT2Al20 alloys both experimentally and by Density Functional theory (DFT) calculations. Study on the ThT2Al20 systems (where T=Ti, V, Cr, Mn and Fe) was previously performed by our group suggesting that the magnetic moment of T atoms can be used as a good descriptor of phase stability [4-5]. Now, we focus on the investigation of the AMn2Al20, where A elements were selected according to their electronic structure. Theoretical and experimental results were found to be in perfect agreement. By analyzing the density of states (DOS) we found that the different behavior of the 4f and 5f-shell electrons of the heavy atom, eventually determines which structure will be favorable [6].
While studying these A-T-Al systems new unknown ternary phases were discovered: Th2Ni10Al15 [7] and Nd2Re3Al15. Since in both cases the alloys of an interest did not attain equilibrium state despite the prolonged heat treatments - they contained multiple phases. Therefore, electron crystallography methods were the only viable tool applicable for structure solution of these phases. In current research, electron diffraction tomography (EDT) approach was successfully used for solution of atomic structure of both phases.

Boundary layers control the transport of momentum, heat, solutes and other quantities between walls and the bulk of a flow. The Prandtl-Blasius boundary layer was the first quantitative example of a flow profile near a wall and could be derived by an asymptotic expansion of the Navier-Stokes equation. For higher flow speeds we have scaling arguments and models, but no derivation from the Navier-Stokes equation.
The analysis of exact coherent structures in plane Couette flow reveals ingredients of such a more rigorous description of boundary layers. I will describe how exact coherent structures can be scaled to obtain self-similar structures on ever smaller scales as the Reynolds number increases.
A quasilinear approximation allows to combine the structures self-consistently to form boundary layers. Going beyond the quasilinear approximation will then open up new approaches for controlling and manipulating boundary layers.

The observation of spontaneous calcium oscillations of ~ 1Hz in beating cardiac cells is typically explained by many coupled chemical reactions and parameters. We show that the separation of time scales of fast processes with slower calcium diffusion in the cell results in a single, non-linear dynamical equation that characterizes these oscillations with only a few physically relevant parameters. Motivated by recent experiments, we predict how the beating can be entrained to an external, oscillatory electric or mechanical strain field and compare our predictions for the onset of entrainment to measurements. We further demonstrate, both experimentally and theoretically, that a much slower time scale (minutes to hours) can be extracted from analysis of the noisy dynamics of beating.