Max Planck Institutes and Experts

The terrestrial biosphere is an integral component of the Earth system. Are there general principles which might explain and predict the functioning of the biosphere and its interaction with the Earth system? This question is central to the work of the biospheric theory and modeling group at the Max-Planck-Institute for Biogeochemistry, and is addressed by using concepts from thermodynamics, statistical mechanics and optimality. After a brief description of the biosphere as a dissipative system, three examples are given to demonstrate the strength of these approaches.

Biological systems inspire the design of new engineering materials due to their light weight structures and high adaptivity. A fist fundamental step in this biomimetic process is to understand and to extract the underlying structure-function relationships. Trees are particularly well suited for such “bio-inspired” studies since they develop high quality structures which may last for thousands of years and growing to 100 m height. This article provides an insight into recent research activities on the mechanical design of wood cell walls and emphasises how effectively trees control mechanical properties by adjusting the structural organisation of the cell wall.

High energy synchrotron radiation tomography allows the visualisation of creep damage in the bulk of materials. The results of the experiments reveal the time-dependent evolution of the time dependence of damage of samples and will contribute significantly to understanding the behaviour of high temperature materials.

As the active component within composite coatings conducting polymers have a great potential as effective and environmentally friendly corrosion pigments. However, this only works, if extended percolation networks of the conducting polymer are avoided in the coating.

We present in situ real-time observations of pitting corrosion as it spreads across the surface of stainless steel in an electrolytic solution. By applying simultaneously two different imaging methods, i.e. ellipsomicroscopy and contrast-enhanced microscopy, the correlation between oxide film weakening and the nucleation and reactivation of individual pits is examined. The existence of front propagation as a component of the transition to pitting corrosion shows that characteristics of this process are consistent with the behavior of stochastic reaction-diffusion systems .